CN103348582A - Motor drive-control apparatus - Google Patents

Abstract

The present invention can grasp the rotational speed of the motor before starting, and perform high-performance driving control of the motor after starting without a rotor position sensor. The pre-start rotation speed detection unit (27) detects the rotation speed of the fan motor (51) before startup. The sensorless control circuit (28) estimates the rotor position of the fan motor (51) and the rotational speed of the fan motor (51) after starting in a rotor position sensorless manner. The microcomputer (29) controls the fan motor (51) according to the first rotational speed signal (FG1) or the second rotational speed signal (FG2). The first rotational speed signal (FG1) represents the rotational speed of the fan motor (51) detected by the pre-start rotational speed detection unit (27), and the second rotational speed signal (FG2) represents the fan motor (51) estimated by the sensorless control circuit (28). 51) The rotational speed. The switching circuit (30) performs a signal switching action, so that the microcomputer (29) is input with the first speed signal (FG1) before the fan motor (51) is started, and the microcomputer (29) is input with the first speed signal (FG1) after the fan motor (51) is started. 2 speed signal (FG2).

Description

Motor drive control device

technical field

The invention relates to a motor drive control device. the

Background technique

The outdoor unit of the heat pump device has various equipment such as a compressor, a fan, and a heat exchanger. As the driving source of the compressor and the fan, for example, a brushless DC (direct current) motor is used. The outdoor unit has a structure in which air is sent to the heat exchanger by the rotation of the fan so that heat is exchanged in the outdoor unit. the

However, the fan of the outdoor unit may already be rotating due to the influence of wind or the like before the motor is started. If the fan spins before the motor starts, it is possible that air is being sent to the heat exchanger inside the outdoor unit, and it may be possible to drive the motor without it. Therefore, it is desirable to grasp the rotational speed of the motor before starting. the

As for the method of grasping the motor rotation speed before starting, there is, for example, the method disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 7-337080). the

Contents of the invention

The problem to be solved by the invention

In a brushless DC motor drive device that drives a brushless DC motor, in order to promote cost reduction, it is attempted to adopt a so-called rotor position sensorless method, that is, without using a rotor position sensor such as a Hall sensor. The rotor position and speed are estimated and the motor is driven. However, the rotor position sensorless method usually estimates the rotor position only after the motor is started, so even when the fan connected to the motor in the non-started state is already rotating due to the influence of wind, for example, no pre-starting is performed. Estimation of rotor position. Therefore, in the rotor position sensorless system, it is impossible to grasp at what number the fan is rotating before starting, and it is impossible to perform drive control of the motor corresponding to the rotation state. the

In addition, based on the above-mentioned reasons, in the rotor position sensorless method, if the motor is started from the rotating state, it is possible that the inverter included in the brushless DC motor drive device may have faults such as overcurrent or overvoltage, which will eventually cause the heat pump to fail. The device, etc. stops. the

On the other hand, it is conceivable to use the method of the above-mentioned Patent Document 1 as means for grasping the motor rotation speed when performing motor drive control. However, in this method, the detection circuit is complicated and cost reduction cannot be achieved, and it cannot be applied to a control method for sinusoidal wave driving, so it is difficult to perform high-efficiency and low-noise high-performance motor drive control. the

Therefore, an object of the present invention is to grasp the rotational speed of the motor before starting, and perform drive control of the high-performance motor without a rotor position sensor after starting. the

The means used to solve the problem

A motor drive control device according to a first aspect of the present invention includes a pre-start rotation speed detection unit, a sensorless estimation unit, a control unit, and a switching circuit. The pre-start rotation speed detection unit detects the rotation speed of the motor before start. The sensorless estimating unit estimates the rotor position of the motor after startup in a rotor position sensorless manner, and estimates the rotational speed of the motor based on the estimated rotor position. The control unit controls the motor based on the first rotational speed signal or the second rotational speed signal. The first rotational speed signal is a signal indicating the rotational speed of the motor detected by the pre-start rotational speed detection unit. The second rotational speed signal is a signal indicating the rotational speed of the motor estimated by the sensorless estimation unit. The switching circuit switches the signals input to the control unit so that the control unit receives the first rotation speed signal before starting the motor, and the control unit receives the second rotation speed signal after starting the motor. the

According to this kind of motor drive control device, the signal input to the control part is switched through the switching circuit, so that the control part is input with the speed of the motor before starting detected by the speed detection part before starting (that is, the first speed signal) before the motor is started. ), after the motor is started, the control unit is input with the rotational speed of the motor after starting (that is, the second rotational speed signal) estimated by the sensorless estimation unit. Therefore, the control unit can grasp the rotational speed of the motor before starting, and use the rotational speed of the motor estimated by the rotor position sensorless method after starting to control the motor. Therefore, the motor drive control device can grasp the rotational speed of the motor before starting, and perform high-performance motor drive control in a rotor position sensorless manner after starting. In addition, when viewed from the control unit side, the control unit receives only one signal that is a signal indicating the rotational speed of the motor. Therefore, the control unit can have only one input port for the signal indicating the rotational speed of the motor. the

A motor drive control device according to a second aspect of the present invention is the motor drive control device according to the first aspect, wherein the pre-start rotational speed detection unit, the sensorless estimation unit, and the switching circuit are packaged in one integrated circuit package. the

Thereby, the motor drive control device itself is very compact, and further downsizing of an outdoor unit or the like to which the motor drive control device is mounted can be achieved. the

A motor drive control device according to a third aspect of the present invention includes a pre-start rotation speed detection unit, a sensorless estimation unit, and a control unit. The pre-start rotation speed detection unit detects the rotation speed of the motor before start. The sensorless estimating unit estimates the rotor position of the motor after startup in a rotor position sensorless manner, and estimates the rotational speed of the motor based on the estimated rotor position. The control unit controls the motor based on the first rotational speed signal or the second rotational speed signal. The first rotational speed signal is a signal indicating the rotational speed of the motor detected by the pre-start rotational speed detection unit. The second rotational speed signal is a signal indicating the rotational speed of the motor estimated by the sensorless estimation unit. In addition, the control unit has switching means. The switching unit switches the signals used for controlling the motor, so that the motor is controlled according to the first rotational speed signal before the motor is started, and the motor is controlled according to the second rotational speed signal after the motor is started. the

According to this motor drive control device, the signal is switched inside the control unit so that the motor speed before starting detected by the speed detection unit before starting (that is, the first speed signal) is used in the motor control before the motor is started. , the rotational speed of the motor after starting (that is, the second rotational speed signal) estimated by the sensorless estimating unit is used in the motor control after the motor is started. Accordingly, the control unit can grasp the rotational speed of the motor before starting, and use the rotational speed of the motor estimated by the rotor position sensorless method after starting to control the motor. Therefore, the motor drive control device can grasp the rotational speed of the motor before starting, and perform high-performance motor drive control in a rotor position sensorless manner after starting. In addition, there is no need for a "switching circuit" as in the first aspect, so the motor drive control device itself is more compact than the first aspect, and even an outdoor unit equipped with a motor drive control device can be more compact than the first aspect. change. the

A motor drive control device according to a fourth aspect of the present invention is the motor drive control device according to any one of the first to third aspects, wherein the sensorless estimation unit uses a predetermined mathematical model related to motor control to estimate the rotor Location. the

According to such a motor drive control device, a predetermined mathematical model related to control of the motor is used for estimating the rotor position, so that the rotor position can be estimated with high accuracy. the

A motor drive control device according to a fifth aspect of the present invention is the motor drive control device according to any one of the first to third claims, wherein the sensorless estimation unit estimates the rotor position by passing a current through the motor. the

According to such a motor drive control device, the rotor position can be estimated with high accuracy by energizing the motor and estimating the position of the rotor using information on the energization state (for example, voltage applied to the motor, current flowing through the motor, etc.). the

A motor drive control device according to a sixth aspect of the present invention is the motor drive control device according to any one of the first to fifth aspects, wherein the motor drive control device further includes an inverter. The inverter supplies power to the motor. In addition, the sensorless estimation unit estimates the rotor position only when controlling the inverter. the

According to such a motor drive control device, since the rotor position is estimated only when the inverter is controlled, the rotor position can be reliably estimated. In addition, since a voltage detector or a current detector normally used in inverter control can be directly used when estimating the rotor position, it is not necessary to add a new circuit, and the motor drive control device can be downsized at low cost. the

A seventh aspect of the present invention is the motor drive control device according to any one of the first to sixth aspects, wherein the sensorless estimation unit cannot estimate the rotational speed of the motor before starting. the

In such a motor drive control device, although the sensorless estimating unit cannot estimate the rotational speed of the motor before starting, a “pre-starting rotational speed detection unit” is provided as a functional unit for grasping the rotational speed of the motor before starting. In addition, the signal indicating the rotational speed of the motor used for motor control is switched before and after starting the motor. Thereby, the rotation speed of the motor before starting can be easily grasped with a simple structure, and the rotation speed of the motor estimated by the rotor position sensorless method can be used for control of the motor after starting. Therefore, the motor drive control device can grasp the rotational speed of the motor before starting, and precisely perform drive control of the motor in a rotor position sensorless system after starting. the

The motor drive control device according to the eighth aspect of the present invention is the motor drive control device according to any one of the first to seventh aspects, wherein the rotation speed detection unit before starting does not use a predetermined mathematical model related to the control of the motor. In the case of the motor speed detection before starting. the

According to such a motor drive control device, the pre-start rotational speed detection unit does not detect the rotational speed of the motor by a so-called rotor position sensorless method using a predetermined mathematical model related to control of the motor. Therefore, even if the motor is not started, the pre-start rotation speed detection unit can reliably detect the rotation speed of the motor. the

A ninth aspect of the present invention is the motor drive control device according to any one of the first to eighth aspects, wherein the pre-start rotational speed detection unit performs the pre-start motor speed detection. the

According to such a motor drive control device, the rotational speed detection unit before starting does not detect the rotational speed of the motor by a so-called rotor position sensorless method as in estimating the rotor position by energizing the motor. Therefore, even if the motor is not started, the pre-start rotation speed detection unit can reliably detect the rotation speed of the motor. the

A motor drive control device according to a tenth aspect of the present invention is the motor drive control device according to any one of the first to ninth aspects, wherein the motor drive control device further includes an inverter. The inverter supplies power to the motor. In addition, the pre-start rotation speed detection unit detects the rotation speed of the motor before starting even without controlling the inverter. the

According to such a motor drive control device, the pre-start rotation speed detection unit can reliably detect the rotation speed of the motor even before the motor is started without inverter control. the

A motor drive control device according to an eleventh aspect of the present invention is the motor drive control device according to any one of the eighth to tenth aspects, wherein the rotation speed detection unit before starting estimates the rotor position before starting, and uses the result to perform Detection of motor speed before starting. the

The pre-start rotational speed detecting unit of such a motor drive control device adopts a sensorless system capable of estimating the rotor position before start. Therefore, the pre-start rotation speed detection unit can reliably detect the rotation speed of the motor even before the motor is started. the

The motor drive control device of the twelfth aspect of the present invention is the motor drive control device described in any one of the eighth to tenth aspects, wherein the rotation speed detection unit before starting detects the The speed of the motor before starting. the

In such a motor drive control device, even before starting, the pre-starting rotational speed detection unit can detect the rotational speed of the motor before starting from an induced voltage that may be generated when the motor rotates. Therefore, the rotation speed of the motor before starting can be detected with a relatively simple structure. the

A motor drive control device according to a thirteenth aspect of the present invention is the motor drive control device according to any one of the first to twelfth aspects, wherein the control unit drives the motor to Start without a rotor position sensor. Furthermore, the control unit does not start the motor when the first rotational speed signal is equal to or greater than a predetermined rotational speed. the

Here, it is assumed that the motor drive control device is used as a drive control system for a fan motor included in an outdoor unit of a heat pump device, for example. In the state where the motor has been rotating due to the influence of wind, etc. before starting, as long as its speed is above the predetermined speed, the heat exchanger in the outdoor unit has already been supplied with enough air, so the motor drive control device does not make the motor start. Conversely, if the rotational speed is less than the predetermined rotational speed, the amount of air supplied to the heat exchanger in the outdoor unit is insufficient even assuming that the motor is rotating, so the motor drive control means starts the motor. In this way, since the starting execution of the motor is controlled according to the rotational speed of the motor before starting, the power consumption caused by the starting of the motor can be minimized without degrading the performance of the heat pump device equipped with the motor drive control device. In addition, since the rotation state immediately before starting is limited, the motor current and the voltage applied to the motor will not increase too much even when external disturbances such as sudden wind blowing are received, and the system driven by the motor will not cause excessive damage. Stopped due to current or overvoltage. the

The motor drive control device according to the fourteenth aspect of the present invention is in the motor drive control device described in any one of the first to thirteenth aspects, the switching operation of the signal from the first rotation speed signal to the second rotation speed signal is This is performed when the rotor position can be estimated by the sensorless estimation unit. the

According to such a motor drive control device, when the motor is started and the rotor position can be estimated by the sensorless estimating unit, the switching operation of the signal indicating the motor rotational speed is performed. That the sensorless estimating unit can estimate the rotor position means that the rotational speed of the motor can be estimated from the estimated rotor position. Therefore, the motor can be reliably driven without a rotor position sensor. the

A motor drive control device according to a fifteenth aspect of the present invention is the motor drive control device according to any one of the first to fourteenth aspects, wherein the signal format of the first rotational speed signal is the same as that of the second rotational speed signal. . the

Thus, when the switching operation of the signal indicating the motor rotational speed is performed by the switching circuit (the first aspect), the control unit can have only one input port for the signal. Therefore, even when either the first rotation speed signal or the second rotation speed signal is input, it is not necessary to change the control method according to the input signal. Moreover, when the switching operation is performed in the control unit (the third aspect), although the first input port for the rotational speed signal and the input port for the second rotational speed signal are respectively provided in the control unit, it is not necessary to use Signal change control method. the

The motor drive control device according to the sixteenth aspect of the present invention is the motor drive control device according to any one of the first to fifteenth aspects, wherein the control unit judges that there is no sensor based on the first rotation speed signal and the second rotation speed signal. Assess whether there is any abnormality in the department. the

For example, when the signal used for motor control is switched from the first rotational speed signal to the second rotational speed signal, assuming that the first rotational speed signal immediately before the switch indicates a rotational speed other than "0rpm", the second rotational speed signal immediately after the switch Indicates the rotational speed of "0rpm". In this case, since the sensorless estimating unit determines the rotational speed of the motor as “0 rpm” although the motor is likely to be rotating, the control unit can determine that the sensorless estimating unit is abnormal. Therefore, the motor drive control device can perform control to immediately stop the start of the motor based on the state of the sensorless estimation unit, and can maintain a high degree of safety. the

The motor drive control device according to the seventeenth aspect of the present invention is the motor drive control device according to any one of the first to sixteenth aspects, wherein the motor is one of the devices included in the outdoor unit of the heat pump device. Drive source of the fan. the

According to such a motor drive control device, even if the fan has rotated before starting due to the influence of wind or the like, the rotational speed of the motor before starting can be easily grasped, and the drive control of the motor can be precisely performed after starting. the

Invention effect

According to the motor drive control device according to the first aspect of the present invention, it is possible to grasp the rotational speed of the motor before starting, and perform high-performance motor drive control after starting without a rotor position sensor. In addition, the control unit may have only one input port for a signal indicating the rotational speed of the motor. the

According to the motor drive control device according to the second aspect of the present invention, the motor drive control device itself is very compact, and further downsizing of an outdoor unit or the like to which the motor drive control device is mounted can be achieved. the

According to the motor drive control device according to the third aspect of the present invention, the rotational speed of the motor before starting can be grasped, and high-performance motor drive control can be performed without a rotor position sensor after starting. In addition, the motor drive control device itself is more compact than the first aspect, and even an outdoor unit equipped with the motor drive control device can be further miniaturized compared with the first aspect. the

According to the motor drive control devices of the fourth and fifth aspects of the present invention, the rotor position can be estimated with high accuracy. the

According to the motor drive control device of the sixth aspect of the present invention, the rotor position can be reliably estimated. In addition, the motor drive control device can be downsized at low cost without adding a new circuit. the

According to the motor drive control device according to the seventh aspect of the present invention, the rotational speed of the motor before starting can be grasped, and the drive control of the motor can be precisely performed in a rotor position sensorless system after starting. the

According to the motor drive control device according to the eighth and ninth aspects of the present invention, even if the motor is not started, the pre-start rotation speed detection unit can reliably detect the rotation speed of the motor. the

According to the motor drive control device of the tenth aspect and the eleventh aspect of the present invention, the pre-start rotation speed detection unit can reliably detect the rotation speed of the motor even before the motor is started. the

According to the motor drive control device according to the twelfth aspect of the present invention, the rotational speed of the motor before starting can be detected with a relatively simple structure. the

According to the motor drive control device according to the thirteenth aspect of the present invention, since the start-up execution of the motor is controlled according to the rotational speed of the motor before start-up, power consumption due to the start-up of the motor can be suppressed to a minimum. And the performance of the heat pump device installed with the motor drive control device will not be reduced. In addition, because the rotation state immediately before starting is limited, even when external disturbances such as sudden wind blowing are received, the increase of the motor current and the voltage applied to the motor will not be too large, and the motor-driven system will not be damaged by overcurrent. or stop due to overvoltage. the

According to the motor drive control device of the fourteenth aspect of the present invention, the motor can be reliably driven without a rotor position sensor. the

According to the motor drive control device according to the fifteenth aspect of the present invention, the control unit does not need to change the control method based on the input first rotation speed signal or the second rotation speed signal, nor does it need to change the control method based on the first rotation speed signal used in the control of the motor. Or change the control method with the second rotational speed signal. the

According to the motor drive control device according to the sixteenth aspect of the present invention, it is possible to perform control to immediately stop the start of the motor based on the state of the sensorless estimation unit, and it is possible to maintain a high degree of safety. the

According to the motor drive control device of the seventeenth aspect of the present invention, even if the fan has rotated before starting due to the influence of wind or the like, the rotation speed of the motor before starting can be easily grasped, and after starting, high-performance motor operation can be performed. drive control. the

Description of drawings

FIG. 1 is a block diagram showing an overall configuration of a system using a motor drive control device according to a first embodiment and an internal configuration of the motor drive control device. the

Fig. 2 is a diagram schematically showing the configuration of an outdoor unit of the heat pump device. the

3 is a diagram schematically showing an example of a configuration of a pre-start rotation speed detection unit. the

FIG. 4 is a diagram showing an example of a configuration of a sensorless control circuit. the

5 is a flowchart for explaining the operation of the motor drive control device according to the first embodiment. the

6 is a diagram schematically showing the configuration of a motor drive control device according to Modification 1F of the first embodiment. the

7 is a block diagram showing the overall configuration of a system using the motor drive control device of the second embodiment and the internal configuration of the motor drive control device. the

Detailed ways

Next, the motor drive control device of the present invention will be described in detail using the drawings. the

<First embodiment>

(1) Summary

FIG. 1 is an overall configuration diagram of a motor drive control system 100 including a brushless DC motor 51 and a motor drive control device 20 of the present embodiment for driving the brushless DC motor 51 . The brushless DC motor 51 is a fan motor used as a drive source of the outdoor fan 15 which is one of the devices included in the outdoor unit 10 (see FIG. 2 ) of the heat pump apparatus. The motor drive control device 20 is installed in the outdoor unit 10 . the

(1-1) Outdoor unit

Here, the outdoor unit 10 will be briefly described using FIG. 2 . Here, regarding the heat pump device, an outdoor unit of a heat pump water heater will be described as an example. The outdoor unit 10 mainly includes various devices such as a compressor 11 , a water heat exchanger 12 , an expansion valve 13 , an evaporator 14 , and an outdoor fan 15 . The compressor 11, the water heat exchanger 12, the expansion valve 13, and the evaporator 14 are connected in sequence to constitute a refrigeration cycle (refrigerating cycle). The compressor 11 compresses the refrigerant circulating in the refrigeration cycle. The water heat exchanger 12 is provided with a heat exchange water channel 16, and the water sent from the hot water tank unit (not shown) connected to the outdoor unit 10 passes through the heat exchange water channel 16, and the water flowing through the heat exchange water channel 16 Heat exchange is possible between water and refrigerant. The expansion valve 13 is an electric valve controlled electrically, and depressurizes the refrigerant circulating in the refrigeration cycle. The evaporator 14 is used to exchange heat between the refrigerant in the refrigerant cycle and air to evaporate the refrigerant. The outdoor fan 15 is, for example, a propeller fan, and guides air from the outside of the outdoor unit 10 to the evaporator 14 by rotation. the

In such an outdoor unit 10 , by driving the compressor 11 to circulate the refrigerant, the water heat exchanger 12 can function as a condenser to heat water passing through the heat exchange water channel 16 . the

(1-2) motor

Next, the brushless DC motor 51 will be described. The brushless DC motor 51 of this embodiment is a three-phase motor and has a stator 52 and a rotor 53 . The stator 52 includes U-phase, V-phase, and W-phase drive coils Lu, Lv, and Lw that are star-connected. One end of each drive coil Lu, Lv, and Lw is connected to drive coil terminals TU, TV, and TW of the respective U-phase, V-phase, and W-phase wirings extending from the inverter 25 . The other ends of the drive coils Lu, Lv, and Lw are connected to each other as terminals TN. These three-phase drive coils Lu, Lv, and Lw are rotated by the rotor 53 to generate induced voltages corresponding to the rotation speed and the position of the rotor 53 . the

The rotor 53 includes two-pole permanent magnets including N poles and S poles, and rotates about the rotation axis relative to the stator 52 . The rotation of the rotor 53 is output to the outdoor fan 15 through an output shaft (not shown) coaxial with the rotation shaft. the

Hereinafter, the brushless DC motor 51 will be described as a fan motor 51 . the

(2) The structure of the motor drive control device

Next, the configuration of the motor drive control device 20 of the present embodiment will be described. As shown in FIG. 1 , the motor drive control device 20 of this embodiment includes a rectifier 21, a smoothing capacitor 22, a voltage detection unit 23, a current detection unit 24, an inverter 25, a gate drive circuit 26, and a pre-start rotation speed detection unit 27. , a sensorless control circuit 28 (corresponding to a sensorless estimation unit), a microcomputer 29 (corresponding to a control unit), and a switching circuit 30 . the

These functional parts constituting the motor drive control device 20 are mounted on, for example, a printed circuit board. In particular, in the present embodiment, the gate drive circuit 26 , the pre-start rotational speed detection unit 27 , the sensorless control circuit 28 and the switching circuit 30 are packaged in one integrated circuit package pa1 . That is, each functional unit 26, 27, 28, 30 is constituted by one IC or HIC. the

(2-1) Rectification unit

The rectification unit 21 is configured in a bridge shape by four diodes D1a, D1b, D2a, and D2b. Specifically, diodes D1a and D1b, D2a and D2b are connected in series with each other, respectively. Each of the cathode terminals of the diodes D1 a and D2 a is connected to the positive side terminal of the smoothing capacitor 22 , and functions as a positive side output terminal of the rectification unit 21 . Each anode terminal of the diodes D1 b and D2 b is connected to the negative side terminal of the smoothing capacitor 22 , and functions as a negative side output terminal of the rectification unit 21 . A connection point between diodes D1a and D1b and a connection point between diodes D2a and D2b are connected to commercial power supply 91 , respectively. That is, the connection point between the diodes D1a and D1b and the connection point between the diodes D2a and D2b each play the role of the input of the rectification unit 21 . the

The rectifying unit 21 having such a configuration generates DC power by rectifying the AC voltage output from the commercial power supply 91 , and supplies the DC power to the smoothing capacitor 22 . the

(2-2) smoothing capacitor

One end of the smoothing capacitor 22 is connected to the positive output terminal of the rectification unit 21 , and the other end is connected to the negative output terminal of the rectification unit 21 . The smoothing capacitor 22 smoothes the DC power supplied from the rectification unit 21 , that is, the voltage rectified by the rectification unit 21 . Hereinafter, for convenience of description, the voltage smoothed by the smoothing capacitor 22 is referred to as "smoothed voltage VfI". The smoothed voltage VfI is a voltage whose ripples are lower than the voltage of the DC power supply, and is applied to the inverter 25 connected to the output side that is a subsequent stage of the smoothing capacitor 22 . the

In addition, examples of the type of capacitor include electrolytic capacitors, ceramic capacitors, tantalum capacitors, and the like. In this embodiment, a case where an electrolytic capacitor is used as the smoothing capacitor 22 is taken as an example. the

(2-3) Voltage detection unit

The voltage detection unit 23 is connected to the output side of the smoothing capacitor 22 and detects the value of the smoothed voltage VfI which is the voltage across the smoothing capacitor 22 . In particular, the voltage detection unit 23 performs a voltage detection operation after the fan motor 51 is started. the

Such a voltage detection unit 23 is configured, for example, by connecting two resistors connected in series to each other in parallel to the smoothing capacitor 22 to divide the smoothed voltage VfI, but is not shown in the figure. The voltage value at the connection point between the two resistors is input to the sensorless control circuit 28 . the

(2-4) Current detection unit

The current detection unit 24 is connected between the smoothing capacitor 22 and the inverter 25 , and is also connected to the negative output terminal side of the smoothing capacitor 22 . The current detection unit 24 detects the motor current Im flowing through the fan motor 51 after the fan motor 51 starts. the

Such a current detection unit 24 is constituted by, for example, an amplifier circuit using a shunt resistor and an operational amplifier for amplifying the voltage across the resistor, but is not shown in the figure. The motor current detected by the current detection unit 24 is input to the sensorless control circuit 28 . the

(2-5) Inverter

The inverter 25 is connected to the output side of the smoothing capacitor 22 . As shown in FIG. 1, the inverter 25 includes a plurality of insulated gate bipolar transistors (hereinafter simply referred to as transistors) Q3a, Q3b, Q4a, Q4b, Q5a, Q5b, and a plurality of return diodes D3a, D3b, D4a, D4b. , D5a, D5b. Transistors Q3a and Q3b, Q4a and Q4b, Q5a and Q5b are connected in series with each other, and each of diodes D3a to D5b is connected in parallel to each of transistors Q3a to Q5b in such a manner that the collector terminal of the transistor is connected to the cathode terminal of the diode, and the emitter of the transistor terminal to the anode terminal of the diode. The inverter 25 is supplied with the smoothed voltage from the smoothing capacitor 22, and each of the transistors Q3a to Q5b is turned on and off at the timing instructed by the gate drive circuit 26, thereby generating the drive voltage SU, SV, SW. The drive voltages SU, SV, SW are output to the fan motor 51 from connection points NU, NV, NW of the transistors Q3a, Q3b, Q4a, Q4b, Q5a, Q5b. That is, the inverter 25 supplies electric power to the fan motor 51 . the

In particular, the inverter 25 of the present embodiment starts or pauses the fan motor 51 according to the number of rotations of the fan motor 51 before starting. Specifically, when the rotational speed of the fan motor 51 before starting is less than a predetermined rotational speed, the sensorless control circuit 28 sends gate voltages Gu, Gx, Gv, Gy, Gw, Gz indicating the start of starting, so that the inverter 25 outputs driving voltages SU, SV, SW to the fan motor 51 . Thereby, the fan motor 51 starts to start. However, when the rotational speed of the fan motor 51 before starting is above the predetermined rotational speed, the gate voltages Gu, Gx, Gv, Gy, Gw, and Gz indicating the start of starting are not sent from the gate drive circuit 26, so the inverter 25 The drive voltages SU, SV, and SW are not output to the fan motor 51 . As a result, the fan motor 51 remains in a non-activated state. the

This is considered to be that at the moment before starting, if the outdoor fan 15 is affected by wind or the like so that the fan motor 51 is already rotating at a sufficient rotational speed, the evaporator 14 has been supplied with enough air by the rotation of the outdoor fan 15 . In this case, the function of the evaporator 14 as a heat pump device is not impaired, and thus the inverter 25 may not output the driving signals SU, SV, SW to the fan motor 51. However, if the rotation speed of the fan motor 51 before starting is insufficient (including the case where the fan motor 51 is not rotating before starting), the evaporator 14 is not supplied with enough air. That is, since there is a possibility that the evaporator 14 cannot function sufficiently, the inverter 25 outputs drive signals SU, SV, and SW to the fan motor 51 to start the fan motor 51 . the

(2-6) Gate drive circuit

The gate drive circuit 26 changes the on and off states of the respective transistors Q3 a to Q5 b of the inverter 25 in accordance with the command voltage Vpwm from the sensorless control circuit 28 . Specifically, the gate drive circuit 26 generates gate voltages Gu, Gx, Gv, Gy, Gw, and Gz to be applied to the gates of the respective transistors Q3a to Q5b so that the inverter 25 outputs a sensor-less voltage to the fan motor 51. The driving voltage SU, SV, SW of the duty ratio determined by the control circuit 28 . The generated gate voltages Gu, Gx, Gv, Gy, Gw, and Gz are applied to the gate terminals of the respective transistors Q3a to Q5b. the

(2-7) Speed detection unit before starting

The input of the pre-start rotational speed detection unit 27 is connected to the W-phase drive coil terminal TW of the fan motor 51 , and the output is connected to the switching circuit 30 . That is, it can be said that the pre-start rotational speed detection unit 27 is located on the rear stage side of the inverter 25 . The pre-start rotational speed detection unit 27 detects the pre-start rotational speed of the fan motor 51 mainly based on the induced voltage Vwn generated from the motor 51 when the pre-start fan motor 51 rotates. the

An example of the configuration of such a pre-start rotational speed detection unit 27 is schematically shown in FIG. 3 . FIG. 3 shows a case where the pre-start rotational speed detection unit 27 is composed of a filter 27a, a comparator 27b, and a calculation unit 27c. The filter 27 a is, for example, a low-pass filter, receives an induced voltage Vwn generated by the drive coil Lw of the rotating fan motor 51 , and removes noise components and harmonic components from the induced voltage Vwn. The comparator 27b receives the induced voltage Vwn passed through the filter 27a and the reference voltage Vref having a predetermined voltage value. The comparator 27b outputs a pulse voltage based on the induced voltage Vwn according to the magnitudes of these input voltages. The calculation unit 27 c receives the pulse voltage, calculates the frequency of the voltage, and calculates the rotational speed of the fan motor 51 . The rotational speed signal representing the rotational speed of the fan motor 51 before starting thus obtained is a pulse signal having a cycle corresponding to the rotational speed of the motor 51, or a signal whose frequency is fixed but has a duty ratio corresponding to the rotational speed of the motor 51. pulse signal. The rotational speed signal is input to the microcomputer 29 through the switching circuit 30 . the

As described above, the pre-start rotation speed detection unit 27 of this embodiment detects the rotation speed of the fan motor 51 with a relatively simple structure. That is, the pre-start rotation speed detection unit 27 is configured so that when a predetermined mathematical model related to the control of the fan motor 51 is not used or the fan motor 51 is not energized, as used in the motor drive in the rotor position sensorless method , to detect the rotation speed of the fan motor 51 . Therefore, the pre-start rotational speed detection unit 27 is configured to detect the rotational speed of the fan motor 51 when the fan motor 51 is not activated, that is, when the inverter 25 is not controlled. Therefore, even when the rotor position cannot be estimated by the rotor position sensorless method described later, such as when the fan motor 51 that has not started rotates due to the influence of wind or the like, the pre-start rotation speed detection unit 27 can detect its rotational speed. the

However, on the contrary, since the pre-start rotation speed detector 27 of this embodiment has a relatively simple structure as described above, when the fan motor 51 is actually started and the rotation speed is high to some extent, it cannot detect the rotation speed with high accuracy. Therefore, it can be said that the pre-start rotation speed detector 27 in this embodiment is a functional part provided for detecting the rotation speed of the fan motor 51 before startup because the fan motor 51 is driven without a rotor position sensor as described later. . the

Hereinafter, for convenience of explanation, the signal indicating the rotational speed of the fan motor 51 before starting is described as "the first rotational speed signal FG1". the

(2-8) Sensorless control circuit

The sensorless control circuit 28 is connected to the voltage detection unit 23 and the current detection unit 24 on the front-stage side of the inverter 25 , and is also connected to the gate drive circuit 26 , the microcomputer 29 and the switching circuit 30 . The sensorless control circuit 28 is a circuit for driving the fan motor 51 without a rotor position sensor. the

Specifically, the sensorless control circuit 28 estimates the rotor position of the fan motor 51 after starting in a rotor position sensorless manner, and estimates the rotational speed of the fan motor 51 based on the estimated rotor position. Hereinafter, the signal indicating the rotational speed of the fan motor 51 after starting will be described as "second rotational speed signal FG2". The second rotational speed signal FG2 is input to the microcomputer 29 through the switching circuit 30 . Furthermore, when an operation command including the rotation speed command Vfg is sent from the microcomputer 29, the sensorless control circuit 28 executes the operation command, the estimated rotor position and the rotation speed, and the respective detections of the voltage detection unit 23 and the current detection unit 24. As a result, the duty ratios of the drive voltages SU, SV, SW are determined in a rotor position sensorless manner. Therefore, the control result (command voltage Vpwm) of the sensorless control circuit 28 is used when the gate drive circuit 26 generates the gate voltages Gu, Gx, Gv, Gy, Gw, and Gz. the

Here, the so-called rotor position sensorless method refers to a method that uses various parameters indicating the characteristics of the fan motor 51, the smoothed voltage VfI after the fan motor 51 starts (that is, the detection result of the voltage detection unit 23), the fan motor The motor current Im of 51 (that is, the detection result of the current detection unit 24), the predetermined mathematical model related to the control of the fan motor 51, etc., perform estimation of the rotor position and rotational speed, PI control for the rotational speed, and PI control for the motor current etc. way. Examples of various parameters indicating the characteristics of the fan motor 51 include the winding resistance, inductance component, induced voltage, and number of poles of the fan motor 51 used. the

FIG. 4 schematically shows an example of the configuration of the sensorless control circuit 28 that performs rotor position sensorless control in consideration of a mathematical model. The sensorless control circuit 28 in FIG. 4 is mainly composed of a motor model calculation unit 28a, a rotor position estimation unit 28b, a rotational speed estimation unit 28c, an LPF 28d, a rotational speed control unit 28e, and a current control unit 28f. The motor model calculation unit 28 a uses various parameters representing the characteristics of the fan motor 51 as a motor model, and calculates an ideal value of the motor current from a command voltage to the motor 51 , an estimated rotor position, and an estimated rotation speed. The rotor position estimating unit 28 b receives the result of subtraction processing between the ideal value and the motor current Im actually detected by the current detecting unit 24 as an input, and estimates the current rotor position. The rotational speed estimating unit 28c estimates the current rotational speed of the fan motor 51 using the estimated rotor position. The motor model is corrected by performing correction processing for setting the difference between the ideal value of the motor current and the actual motor current Im to "0" for the estimation results obtained by the estimation units 28b and 28c. The LPF 28d removes noise components and harmonic components from the estimated rotational speed. The rotational speed of the fan motor 51 output from the LPF 28d becomes a desired second rotational speed signal FG2 through the waveform shaping unit 28g, and is output to the microcomputer 29 through the switching circuit 30. The second rotational speed signal FG2 is, like the first rotational speed signal FG, a pulse signal having a period corresponding to the rotational speed of the fan motor 51, or a pulse signal having a fixed frequency but having a duty ratio corresponding to the rotational speed of the motor 51. . the

In addition, subtraction processing is performed between the rotation speed of the fan motor 51 output from the LPF 28 d and the rotation speed command Vfg included in the operation command sent from the microcomputer 29 . The rotation speed control unit 28e performs PI control on the rotation speed after receiving the result of the subtraction processing. The current control unit 28f responds to the d-axis torque current command Id* which is the control result of the rotational speed control unit 28e, the command “Iq*=0” such as setting the q-axis current command Iq to “0”, and the voltage detection unit 23 The detected smoothed voltage VfI performs current control to generate a command voltage Vpwm such that the current is based on these commands. PI control is performed so that the motor current becomes "0". The command voltage Vpwm including the duty ratios of the drive voltages SU, SV, and SW is generated by such control of the current control unit 28f and input to the gate drive circuit 26 . In addition, the command voltage Vpwm is input to the motor model calculation unit 28a, and further correction of the motor model is performed. the

The sensorless control circuit 28 having such a configuration can be said to estimate the rotor position only when the inverter 25 is controlled by the microcomputer 29 and the gate drive circuit 26 . When the control of the inverter 25 is performed, it means that the fan motor 51 is started and driven according to the start command. In other words, the sensorless control circuit 28 cannot estimate the rotational speed of the fan motor 51 before the fan motor 51 starts. This is because, as described above, in the rotor position sensorless system, the estimated rotor position is used for estimating the rotational speed, and thus the rotor position cannot be estimated in the fan motor 51 before starting. the

In addition, the sensorless control circuit 28 of the present embodiment also controls the switching operation of the switching circuit 30 , but this point is not shown in FIG. 4 . The switching operation of the switching circuit 30 will be described in the section “(2-10) Switching circuit 30 ”. the

(2-9) microcomputer

As shown in FIG. 1 , the microcomputer 29 is mainly connected to the switching circuit 30 and the sensorless control circuit 28 . In addition, although the microcomputer 29 is also connected to the outdoor unit side control part which controls each apparatus of the outdoor unit 10 as a whole, this point is not shown in figure. the

The microcomputer 29 controls the fan motor 51 according to the rotation speed of the fan motor 51 , and outputs an operation command including a start command and a rotation speed command Vfg to the sensorless control circuit 28 . In particular, as shown in FIG. 1 , the microcomputer 29 has a rotational speed input port po1 as a port for inputting the rotational speed signal of the fan motor 51 . Therefore, the microcomputer 29 receives any one of the first rotational speed signal FG1 output from the pre-start rotational speed detection unit 27 and the second rotational speed signal FG2 output from the sensorless control circuit 28, and performs The second rotational speed signal FG2 controls the fan motor 51 . the

－Control during starting－

Here, control when the microcomputer 29 activates the fan motor 51 will be described. Before the fan motor 51 starts, the microcomputer 29 must be input with the first rotational speed signal FG1. Before starting the fan motor 51, the microcomputer 29 compares the first rotational speed signal FG1 with a predetermined rotational speed, and determines whether the rotational speed of the fan motor 51 before starting is equal to or greater than a predetermined rotational speed. If the rotational speed represented by the first rotational speed signal FG1 is above the predetermined rotational speed, the fan motor 51 has been rotated at a sufficient rotational speed due to the influence of wind, etc., and the evaporator 14 is supplied with sufficient air even if the fan motor 51 is not activated. Therefore, the microcomputer 29 maintains the state in which the fan motor 51 is not activated. That is, in this case, no operation command including an activation command of the fan motor 51 is sent from the microcomputer 29 to the sensorless control circuit 28, and therefore the respective transistors Q3a to Q5b of the inverter 25 are kept off. On the contrary, if the first rotational speed signal FG1 is lower than the predetermined rotational speed, the evaporator 14 is not supplied with enough air at the current moment, and therefore the microcomputer 29 starts the fan motor 51 . In this case, since the microcomputer 29 sends the operation command including the start command of the fan motor 51 and the rotation speed command Vfg to the sensorless control circuit 28, the respective transistors Q3a to Q5b of the inverter 25 operate at different timings. On and off. the

The aforementioned predetermined rotational speed is pre-set to an appropriate value through theoretical calculations, simulations, experiments, etc., according to the characteristics of the fan motor 51, the outdoor fan 15, and the evaporator 14, and the like. the

－Control during operation without rotor position sensor－

After the fan motor 51 is started, the rotational speed signal input to the microcomputer 29 immediately becomes the second rotational speed signal FG2 rather than the first rotational speed signal FG1, and the microcomputer 29 outputs the operation command of the fan motor 51 according to the second rotational speed signal FG2. the

In addition, the microcomputer 29 can also determine the state of the sensorless control circuit 28 by monitoring the rotation speed indicated by each rotation speed signal FG1 , FG2 including before and after switching of the input rotation speed signal. For example, when the rotation speed signal input to the microcomputer 29 is switched from the first rotation speed signal FG1 to the second rotation speed signal FG2, the first rotation speed signal FG1 immediately before the switch shows a rotation speed other than "0rpm", and the second rotation speed signal immediately after the switching Signal FG2 shows "0 rpm". In this case, the microcomputer 29 determines that there is an abnormality on the sensorless control circuit 28 side. This is because the sensorless control circuit 28 judges the rotational speed as "0 rpm" although the fan motor 51 is more likely to rotate. the

In this way, when it is determined that the sensorless control circuit 28 is in an abnormal state, the microcomputer 29 may send an operation command to immediately stop the fan motor 51 to the sensorless control circuit 28 to stop the drive of the fan motor 51 . In addition, the microcomputer 29 may transmit information indicating that the sensorless control circuit 28 is in an abnormal state to the outdoor unit side control unit or the outside of the outdoor unit 10 . the

(2-10) Switching circuit

The switching circuit 30 is constituted by a switch connected to the pre-start rotational speed detection unit 27 , the sensorless control circuit 28 and the microcomputer 29 . The switching circuit 30 performs the switching operation of the rotational speed signal input to the microcomputer 29 under the control of the switching operation from the sensorless control circuit 28 . the

Specifically, before starting the fan motor 51, the switching circuit 30 connects the rotational speed input port po1 of the microcomputer 29 to the output port of the first rotational speed signal FG1 of the pre-start rotational speed detection unit 27, and connects the rotational speed input port po1 to the non-operating speed input port po1. The output port of the second rotational speed signal FG2 of the sensor control circuit 28 is disconnected so that the first rotational speed signal FG1 output from the pre-start rotational speed detection unit 27 is input to the microcomputer 29 . Conversely, when the fan motor 51 is started and a rotation speed signal switching command is issued from the sensorless control circuit 28, the switching circuit 30 makes the rotation speed input port po1 and the output port of the second rotation speed signal FG2 of the sensorless control circuit 28 In the connected state, the rotational speed input port po1 and the output port of the first rotational speed signal FG1 of the pre-start rotational speed detection unit 27 are disconnected so that the second rotational speed signal FG2 output from the sensorless control circuit 28 is input to the microcomputer 29 . the

Thus, in the present embodiment, either one of the first rotational speed signal FG1 and the second rotational speed signal FG2 is input to the microcomputer 29 by the switching circuit 30 having a simple structure. Therefore, in the present embodiment, both the first rotational speed signal FG1 and the second rotational speed signal FG2 are pulse signals as described above, and the signal form of the first rotational speed signal FG1 and the signal form of the second rotational speed signal FG2 are the same. the

－Switching action of speed signal－

Here, the timing at which the switching circuit 30 switches the connection destination of the rotational speed input port po1 from the pre-start rotational speed detection unit 27 side to the sensorless control circuit 28 side will be described. The switching circuit 30 switches the rotation speed signal input to the microcomputer 29 from the first rotation speed signal FG1 to the second rotation speed signal FG2 at a predetermined timing after the fan motor 51 is started. The following three modes can be considered for the "predetermined timing" . the

(Mode A) First, the detection of the rotor position and rotational speed is performed immediately after starting. Based on the detection result, the sensorless control circuit 28 forcibly energizes the fan motor 51 to fix the position of the rotor 53 at a predetermined position. Through this operation, the sensorless control circuit 28 can estimate the rotor position. The switching circuit 30 performs the switching operation of the rotational speed signal at the timing when the operation of estimating the rotor position by the sensorless control circuit 28 becomes possible. the

(Mode B) When the detection of the rotor position and rotational speed in the above mode A is not performed, the sensorless control circuit 28 forcibly energizes the fan motor 51 to fix the rotor position at a predetermined position. Through this operation, the sensorless control circuit 28 can estimate the rotor position, so the switching circuit 30 performs the switching operation of the rotational speed signal at the timing when the sensorless control circuit 28 can estimate the rotor position. the

(Pattern C) It is assumed that the fan motor 51 that is already rotating due to the influence of wind or the like is started. At this time, the sensorless control circuit 28 may be able to detect the rotor position and the rotational speed depending on the state of the motor 51 already rotating, such as the rotational speed. In this case, the sensorless control circuit 28 can estimate the rotor position without performing forced energization to the fan motor 51 . Therefore, the switching circuit 30 performs the switching operation of the rotational speed signal at the timing when the operation of the sensorless control circuit 28 to estimate the rotor position becomes possible. the

The above modes A to C are summarized as follows. In this embodiment, it can be said that the switching circuit 30 switches the rotation speed signal from the first rotation speed signal FG1 to the second rotation speed signal when the sensorless control circuit 28 becomes capable of estimating the rotor position. Switching action of signal FG2. Since the rotor position can be estimated when the fan motor 51 is started and the driving state of the motor 51 is stabilized thereafter, the sensorless control circuit 28 can output the second rotational speed signal FG2 . the

In addition, which of the modes A to C to adopt can be appropriately determined according to the specifications of the outdoor unit 10 to which the outdoor fan 15 is installed. the

(3) action

Next, the operation of the motor drive control device 20 according to this embodiment will be described using FIG. 5 . FIG. 5 is a flowchart showing operations performed by the motor drive control device 20 . First, assume a state where the switching circuit 30 connects the rotational speed input port po1 of the microcomputer 29 to the output port of the first rotational speed signal FG1 of the pre-start rotational speed detection unit 27 . the

Steps S1-S2: When the microcomputer 29 acquires an instruction to start the operation of the outdoor fan 15 from the outdoor unit-side control unit of the outdoor unit 10 (step S1: Yes), the pre-start rotation speed detection unit 27 detects that the fan motor 51 is started immediately before starting. The rotational speed of the motor 51 at the current moment (step S2 ). Thus, the first rotational speed signal FG1 is input to the microcomputer 29 through the switching circuit 30 . the

Steps S3-S4: The microcomputer 29 compares the first rotational speed signal FG1 detected in step S2 with a predetermined rotational speed (step S3). If the first rotational speed signal FG1 is equal to or higher than the predetermined rotational speed (step S4: Yes), the microcomputer 29 determines that the fan motor 51 is not to be activated at the present time (step S4). In this case, the drive voltages SU, SV, and SW are not output from the inverter 25 to the fan motor 51 . the

Step S5: Every time a predetermined time elapses from the operation of step S2, the operations after step S2 are repeatedly executed. That is, when it is determined in step S2 that the fan motor 51 is not to be started, the pre-start rotation speed detection unit 27 retrives the operation of detecting the fan motor 51 before startup. the

Step S6: If the first rotational speed signal FG1 is lower than the predetermined rotational speed in step S3 (step S3: NO), the microcomputer 29 determines to start the fan motor 51 . In this case, the microcomputer 29 outputs an operation command including a start command and a rotational speed command Vfg to the sensorless control circuit 28, and outputs drive voltages SU, SV, SW from the inverter 25 to the fan motor 51, and the fan motor 51 Get started. the

Steps S7-S8: Until the sensorless control circuit 28 can estimate the rotor position (step S7: No), the switching circuit 30 maintains the state of connecting the rotational speed input port po1 of the microcomputer 29 to the pre-start rotational speed detection unit 27 side. If the sensorless control circuit 28 can estimate the rotor position (step S7: Yes), the switching circuit 30 switches the connection object of the rotational speed input port po1 of the microcomputer 29 from the pre-start rotational speed detection unit 27 side to the sensorless control circuit 28 side, In order to input the second rotational speed signal FG2 to the microcomputer 29 instead of the first rotational speed signal FG1 (step S8). the

Step S9: The fan motor 51 activated in Step S6 is driven without a rotor position sensor by the sensorless control circuit 28 . the

Steps S10 - S12 : until the instruction to stop the drive of the outdoor fan 15 is obtained (step S10 : No), the fan motor 51 continues to be driven by the sensorless rotor position sensor implementing step S9 through the sensorless control circuit 28 . The output of drive voltage SU, SV, SW to the fan motor 51 by the inverter 25 is stopped, and the drive of the fan motor 51 is stopped (step S11). The switching circuit 30 switches the connection destination of the rotational speed input port po1 of the microcomputer 29 from the side of the sensorless control circuit 28 to the side of the rotational speed detection unit 27 before starting, so that the first rotational speed signal FG1 is input to the microcomputer 29 instead of the second rotational speed signal. FG2 (step S12). the

(4) Features

(4-1) According to the motor drive control device 20 of this embodiment, before the fan motor 51 is started, the microcomputer 29 is input with the rotation speed of the fan motor 51 before starting detected by the rotation speed detection unit 27 before starting (that is, the first rotation speed). speed signal FG1). After the fan motor 51 is activated, the microcomputer 29 receives the rotational speed of the fan motor 51 after the activation estimated by the sensorless control circuit 26 (that is, the second rotational speed signal FG2 ). In this way, the rotation speed signal input to the microcomputer 29 is switched by the switching circuit 30 . Therefore, the microcomputer 29 can easily grasp the rotational speed of the fan motor 51 before starting, and use the rotational speed of the fan motor 51 estimated by the rotor position sensorless method for controlling the fan motor 51 after starting. Therefore, the motor drive control device 20 can grasp the rotational speed of the fan motor 51 before starting, and perform high-performance drive control of the fan motor 51 after starting without a rotor position sensor. the

Also, from the perspective of the microcomputer 29 , the microcomputer 29 receives only one rotational speed signal (ie, the first rotational speed signal FG1 or the second rotational speed signal FG2 ) as a signal indicating the rotational speed of the fan motor 51 . Therefore, the microcomputer 29 can have only one input port for inputting a signal indicating the rotational speed of the fan motor 51 . the

(4-2) In addition, in this embodiment, the pre-start rotational speed detection unit 27 , the sensorless control circuit 28 , and the switching circuit 30 are packaged in one integrated circuit package. As a result, the motor drive control device 20 itself is very compact, and further downsizing of the outdoor unit 10 to which the motor drive control device 20 is mounted is achieved. the

(4-3) In addition, according to the motor drive control device 20 of the present embodiment, when the fan motor 51 is activated, the sensorless control circuit 28 uses a predetermined mathematical model related to the control of the fan motor 51 when estimating the rotor position. . Therefore, the rotor position can be estimated with high precision. the

(4-4) That is, according to the motor drive control device 20 of this embodiment, since the sensorless control circuit 28 estimates the rotor position only when the inverter 25 is controlled, the rotor position can be reliably estimated. In addition, the voltage detection unit 23 or the current detection unit 24 normally used in the control of the inverter 25 can be used directly when estimating the rotor position, so that the motor drive control device 20 can be realized at low cost without adding a new circuit. miniaturization. the

(4-5) In the present embodiment, although the sensorless control circuit 28 cannot estimate the rotational speed of the fan motor 52 before starting, the functional unit that grasps the rotational speed of the fan motor 51 before starting is referred to as the "rotational speed detection unit before starting". 27” was set. Furthermore, the rotational speed signals FG1 and FG2 used for the motor control by the microcomputer 29 are switched before and after the start of the fan motor 51 . Therefore, it is possible to easily grasp the rotation speed of the fan motor 51 before starting (that is, the first rotation speed signal FG1 ) with a simple structure, and to obtain the rotation speed of the motor (that is, the second rotation speed signal FG1 ) estimated by the rotor position sensorless method after startup. FG2) is used in motor control. Therefore, the motor drive control device 20 can grasp the rotational speed of the fan motor 51 before starting, and perform high-performance drive control of the fan motor 51 after starting without a rotor position sensor. the

(4-6) In addition, the pre-start rotation speed detection unit 27 of the present embodiment detects the rotation speed of the fan motor 51 before startup without using a predetermined mathematical model related to the control of the fan motor 51 . That is, the pre-start rotational speed detection unit 27 does not detect the rotational speed of the fan motor 51 in a so-called rotor position sensorless system as in using a mathematical model. Therefore, even if the fan motor 51 is not activated, the pre-start rotational speed detection unit 27 can reliably detect the rotational speed of the fan motor 51 . the

(4-7) In addition, the pre-start rotational speed detection unit 27 of the present embodiment does not detect the rotational speed of the motor by a so-called rotor position sensorless method as in estimating the rotor position by energizing the fan motor 51 . Therefore, even if the fan motor 51 is not activated, the pre-start rotational speed detection unit 27 can reliably detect the rotational speed of the fan motor 51 . the

(4-8) In addition, the pre-start rotation speed detection unit 27 of the present embodiment can reliably detect the rotation speed of the fan motor 51 even before the start of the fan motor 51 which is not controlled by the inverter 25 . the

(4-9) Specifically, the pre-start rotational speed detection unit 27 of this embodiment can detect the rotational speed of the fan motor 51 before starting from the induced voltage Vwn that may be generated by the rotation of the fan motor 51 . Therefore, the rotation speed of the fan motor 51 before starting can be detected with a relatively simple structure. the

(4-10) In the state where the fan motor 51 is already rotating due to the influence of wind or the like before starting, as long as its rotational speed is more than a predetermined rotational speed, the evaporator 14 in the outdoor unit 10 has already been supplied with enough air to be able to operate. Since heat exchange is performed, the motor drive control device 20 of the present embodiment does not activate the fan motor 51 . Conversely, if the rotation speed is lower than the predetermined rotation speed, the amount of air supplied to the evaporator 14 in the outdoor unit 10 is insufficient even assuming that the fan motor 51 is rotating, so the motor drive control device 20 starts the fan motor 51 . In this way, since the starting execution of the fan motor 51 is controlled according to the rotational speed of the fan motor 51 before starting, the power consumption caused by the starting of the fan motor 51 can be suppressed to a minimum. Furthermore, the performance of the heat pump device to which this motor drive control device 20 is mounted will not be degraded. In addition, since the rotation state immediately before starting is limited, the motor current and drive voltage will not increase too much even when external disturbances such as sudden wind blowing are received, and the motor drive system 100 will not be damaged by overcurrent or overvoltage. And stop. the

(4-11) The signal switching operation from the first rotational speed signal FG1 to the second rotational speed signal FG2 is performed after the fan motor 51 is started and when the rotor position can be estimated by the sensorless control circuit 28 . The fact that the sensorless control circuit 28 can estimate the rotor position means that the rotational speed of the fan motor 51 can be estimated from the estimated rotor position. Therefore, the fan motor 51 can be reliably driven without a rotor position sensor. the

(4-12) The signal format of the first rotational speed signal FG1 is the same as that of the second rotational speed signal FG2 . Accordingly, the microcomputer 29 can have only one input port for the signal. Therefore, even when either the first rotational speed signal FG1 or the second rotational speed signal FG2 is input, it is not necessary to change the control method according to the input signal. the

(4-13) The microcomputer 29 of the present embodiment determines whether or not there is an abnormality in the sensorless control circuit 28 based on the first rotational speed signal FG1 and the second rotational speed signal FG2 . Therefore, the motor drive control device 20 can perform control to immediately stop the fan motor 51 from starting according to the state of the sensorless control circuit 28, and can have high safety. the

(4-14) The motor 51 is a drive source of the outdoor fan 15 which is one of devices included in the outdoor unit 10 of the heat pump apparatus. According to this motor drive control device 20, even if the outdoor fan 15 has rotated before starting due to the influence of wind, etc., the rotation speed of the fan motor 51 before starting can be easily grasped, and the fan motor 51 can be accurately controlled after starting. drive control. the

(5) Variations

(5-1) Modification 1A

In the above-mentioned first embodiment, it was described that the sensorless control circuit 28 uses a predetermined mathematical model related to the control of the fan motor 51 to estimate the rotor position after the start of the fan motor 51 . However, the sensorless control circuit 28 may estimate the rotor position by passing a current for detecting the rotor position to the fan motor 51 being driven. According to this method, the rotor position can be estimated with high precision by using information on the energized state (eg, drive voltage, motor current, etc.). the

(5-2) Modification 1B

In addition, in the first embodiment described above, the pre-start rotational speed detection unit 27 has been described to detect the rotational speed of the fan motor 51 using the induced voltage Vwm of the fan motor 51 . However, the pre-start rotational speed detection unit 27 may estimate the rotor position of the fan motor 51 before the start, and use the result to detect the rotational speed of the fan motor 51 before the start. That is, the pre-start rotational speed detector 27 in this case adopts a sensorless method capable of estimating the rotor position before starting, rather than a so-called rotor position sensorless system that cannot detect the rotational speed of the fan motor 51 before starting. Accordingly, even before the fan motor 51 is started, the pre-start rotation speed detection unit 27 can reliably detect the rotation speed of the fan motor 51 . the

In addition, as a method of estimating the rotor position before starting in the above-mentioned sensorless method, for example, there is a conventionally known method as shown in FIG. 3 of Patent Document 1 (Japanese Patent Application Laid-Open No. 7-337080 ). In this sensorless method, the rotor position is detected using the inter-terminal voltage of each phase of the fan motor 51 (that is, the induced voltage generated in each phase). the

(5-3) Modification 1C

In the first embodiment described above, as shown in FIG. 3 , the pre-start rotation speed detection unit 27 detects the rotation speed of the fan motor 51 before startup using only the induced voltage of one phase. However, instead of one phase, two or all three phases of the induced voltage used when detecting the rotational speed of the fan motor 51 before starting may be used. In addition, in FIG. 3 , the W-phase induced voltage is used to detect the rotational speed of the fan motor 51 before starting, but the U-phase or V-phase induced voltage may be used instead of the W-phase, that is, it is not limited to the above-mentioned first embodiment. The detection method of the method. the

(5-4) Modification 1D

In the first embodiment described above, it was described that the first rotational speed signal FG1 and the second rotational speed signal FG2 are pulse signals. However, the first rotational speed signal FG1 and the second rotational speed signal FG2 may be DC voltage signals expressing the rotational speed as voltage values. the

(5-5) Modification 1E

In the first embodiment described above, it has been described that the switching circuit 30 is configured by switches. However, the switching circuit 30 may be configured not using a switch but using a logic circuit or the like. the

(5-6) Modification 1F

In the above-mentioned first embodiment, the case where the motor drive control device 20 drives only the fan motor 51 has been described. However, the motor drive control device described above can also be applied to a case where the fan motor 51 and the compressor motor 61 are connected in parallel as shown in FIG. 6 to drive and control the respective motors 51 and 61 . the

FIG. 6 is a block diagram of a system 200 including the motor drive control device 120 when the fan motor 51 and the compressor motor 61 are connected in parallel. In addition, in FIG. 6 , for simplification, the specific internal structures of the rectifying unit 131 and the respective inverters 125 and 133 are omitted, but the internal structures of the rectifying unit 131 and the respective inverters 125 and 133 are the same as those in FIG. 1 . the

The motor drive control device 120 includes a first smoothing capacitor 122 , a voltage detection unit 123 , a current detection unit 124 , a fan inverter 125 , and a fan motor drive IC 126 on the side of the fan motor 51 . The first smoothing capacitor 122 , voltage detection unit 123 , current detection unit 124 , and fan inverter 125 are the same as those of the smoothing capacitor 22 , voltage detection unit 23 , current detection unit 24 , and inverter 25 in the first embodiment. The internal structure of the driving IC 126 on the side of the fan motor 51 is the same as that of the integrated circuit package pa1 shown in FIG. 1 . That is, IC126 for a drive has the same structure as the door drive circuit 26 of the said 1st Embodiment, the rotation speed detection part 27 before starting, the sensorless control circuit 28, and the switching circuit 30. the

In addition, the motor drive control device 120 is configured to include a compressor inverter 133 and a drive IC 136 on the side of the compressor motor 61 on the side of the compressor motor 61 that is a drive source of the compressor 11 . In addition, the motor drive control device 120 has a second smoothing capacitor 132 and a rectification unit 131 connected to the commercial power supply 91 as common configurations for the compressor 11 and the outdoor fan 15 . the

The rectification unit 131 is connected to the commercial power supply 91 and rectifies the AC voltage from the commercial power supply 91 . The second smoothing capacitor 132 is connected in parallel to the first smoothing capacitor 122 and the fan inverter 125 , and smoothes the DC power supplied from the rectifying unit 131 . The voltage smoothed by the second smoothing capacitor 132 is supplied to the compressor inverter 133 and is also supplied to the side of the first smoothing capacitor 122 which is the fan side. The compressor inverter 133 generates a drive voltage for driving the compressor motor 61 and outputs it to the motor 61 . The drive IC 136 on the side of the compressor motor 61 has a gate drive circuit for driving each transistor in the compressor inverter 133, a rotor position estimation circuit for estimating the rotor position, and an operation for the compressor motor 61 based on the rotor position. Sensorless control circuit for sensorless control. the

In addition, the motor drive control device 120 has a microcomputer 130 that controls the fan motor 51 and the compressor motor 61 as a whole. As shown in FIG. 6, the microcomputer 130 functions as a fan motor control system 130a and a compressor motor control system 130b. The fan motor control system 130a performs the same control as that of the microcomputer 29 in the first embodiment described above. The compressor motor control system 130b issues an operation command such as drive start or stop to the compressor motor 61 . the

(5-7) Modification 1G

In addition, in the above-mentioned first embodiment, the switching operation from the first rotational speed signal FG1 to the second rotational speed signal FG2 has been described for each of the pre-starting and post-starting operations. Of course, the switching operation of this mode can also be applied to the case of restarting during rotation during deceleration. the

<Second Embodiment>

In the above-mentioned first embodiment, the case where the rotation speed signals FG1 and FG2 of the fan motor 51 input to the microcomputer 29 are switched by hardware by the switching circuit 30 before and after the motor 51 is started has been described. In this embodiment, a case where the switching operation of the rotational speed signal is performed not by a hardware configuration but by a software configuration will be described. the

(1) Structure

7 is a configuration diagram of an entire motor drive system 300 including a fan motor 51 as a brushless DC motor and a motor drive control device 220 of the present embodiment for driving the fan motor 51 . The motor drive control device 220 has a rectification unit 221, a smoothing capacitor 222, a voltage detection unit 223, a current detection unit 224, an inverter 225, a door drive circuit 226, a pre-start rotation speed detection unit 227, and a sensorless control circuit 228 (equivalent to a sensorless control circuit 228). sensor estimation unit) and microcomputer 229 (equivalent to the control unit). That is, the motor drive control device 220 of the present embodiment has a configuration in which the switching circuit 30 is not provided in the motor drive control device 20 of the first embodiment described above. These functional units constituting the motor drive control device 220 are mounted on, for example, one printed circuit board. The gate drive circuit 226, the pre-start rotational speed detection unit 227, and the sensorless control circuit 228 are packaged in, for example, one integrated circuit package pa201, and constituted by one IC or HIC. the

In addition, the rectifying unit 221, the smoothing capacitor 222, the voltage detecting unit 223, the current detecting unit 224, the inverter 225, the gate driving circuit 226, the rotation speed detecting unit 227 before starting, and the sensorless control circuit 228 are respectively the same as those shown in FIG. The rectification unit 21, smoothing capacitor 22, voltage detection unit 23, current detection unit 24, inverter 25, gate drive circuit 26, pre-start rotational speed detection unit 27, and sensorless control circuit 28 of the first embodiment are the same. Therefore, description of these functional units will be omitted below, and only the microcomputer 229 , which is a part different from the first embodiment described above, will be described. the

(1-1) microcomputer

The microcomputer 229 is directly connected to the pre-start rotation speed detection unit 227 and the sensorless control circuit 228, and is input with the detection result of the pre-start rotation speed detection unit 227, which is the first rotation speed signal FG1, and the detection result of the sensorless control circuit 228, which is the second rotation speed signal. FG2. That is, the microcomputer 229 has two rotational speed input ports po11 and po12 as ports for inputting rotational speed signals. the

This microcomputer 229 is similar to the microcomputer of the above-mentioned first embodiment, before starting the fan motor 51, it performs the control to determine whether the motor 51 should be started according to the first rotational speed signal FG1, and after the fan motor 51 starts, according to the second The rotational speed signal FG2 controls the motor 51 . Therefore, the microcomputer 229 has a switching unit 229 a for switching the rotational speed signal used for controlling the fan motor 51 . Note that the timing at which the switching means 229a switches the rotational speed signal from the first rotational speed signal FG1 to the second rotational speed signal FG2 may be the timing described in "-Switching operation of rotational speed signal-" in the first embodiment above. the

In addition, the microcomputer 229 performs the same control as the microcomputer 29 of the said 1st Embodiment. In addition, the microcomputer 229 can also determine that the sensorless control circuit 228 is present when, for example, when the sensorless control circuit 228 detects the rotational speed of the fan motor 51 and outputs "0 rpm" as the second rotational speed signal FG2 when the rotor position is fixed. abnormal. This is because the value of the second rotational speed signal FG2 is "0 rpm", which means that the rotor position cannot be estimated. the

In addition, when the fan motor 51 is forcedly energized, the second rotational speed signal FG2 output from the sensorless control circuit 228 can be a value indicating a frequency corresponding to the forced energization. In this case, the microcomputer 229 can use the second rotational speed signal FG2 to notify that the fan motor 51 is currently being forcibly energized. the

(2) Features

(2-1) According to the motor drive control device 220 of this embodiment, the signal is switched inside the microcomputer 229 so that before the fan motor 51 starts, the fan motor 51 before starting detected by the pre-start rotation speed detection unit 227 The rotational speed of the fan motor 51 (that is, the first rotational speed signal FG1 ) is used in motor control. After the fan motor 51 is started, the rotational speed of the fan motor 51 after starting (that is, the second rotational speed signal FG2 ) estimated by the sensorless control circuit 228 is used. Used in motor control. Therefore, the microcomputer 229 can easily grasp the rotational speed of the fan motor 51 before starting, and can use the rotational speed of the fan motor 51 estimated by the rotor position sensorless method for motor control after starting. Therefore, it is possible to grasp the rotational speed of the fan motor 51 before starting, and to perform high-performance drive control of the fan motor 51 after starting without a rotor position sensor. the

In addition, there is no need to install the "switching circuit 30" in the above-mentioned first embodiment, so the motor drive control device 220 itself is more compact than the above-mentioned first embodiment. Compared with other methods, further miniaturization can also be achieved. the

(2-2) Also in the motor drive control device 220 of this embodiment, the sensorless control circuit 228 uses a predetermined mathematical model related to the control of the fan motor 51 when estimating the rotor position. Therefore, the rotor position can be estimated with high precision. the

(2-3) That is, also in this embodiment, since the rotor position is estimated by the sensorless control circuit 28 only when the inverter 225 is controlled, the rotor position can be reliably estimated. In addition, the voltage detection unit 223 and the current detection unit 224 that are generally used in the control of the inverter 225 can be directly used when estimating the rotor position, so that the motor drive control device 220 can be realized at low cost without adding a new circuit. miniaturization. the

(2-4) Also in this embodiment, although the sensorless control circuit 228 cannot estimate the rotational speed of the fan motor 51 before starting, it is provided as the "rotational speed before starting detection unit 227" to grasp the fan motor speed before starting. 51 RPM function section. Furthermore, the rotational speed signals FG1 and FG2 used for the motor control by the microcomputer 229 are switched before and after the start of the fan motor 51 . Therefore, the first rotational speed signal FG1 which is the rotational speed of the fan motor 51 before starting can be easily grasped with a simple structure, and the second rotational speed signal FG2 which is the rotational speed of the motor estimated by the rotor position sensorless method can be used for the fan motor 51 after starting. In motor control. Therefore, the motor drive control device 220 can grasp the rotational speed of the fan motor 51 before starting, and perform high-performance drive control of the fan motor 51 in a rotor position sensorless manner after starting. the

(2-5) Also in this embodiment, the pre-start rotation speed detection unit 227 detects the rotation speed of the fan motor 51 before startup without using a predetermined mathematical model related to the control of the fan motor 51 . Therefore, even if the fan motor 51 is not activated, the pre-start rotation speed detection unit 227 can reliably detect the rotation speed of the fan motor 51 . the

(2-6) Also in this embodiment, the pre-start rotational speed detection unit 227 detects the rotational speed of the fan motor 51 before starting without passing current to the fan motor 51 . Therefore, even if the fan motor 51 is not activated, the pre-start rotation speed detection unit 227 can reliably detect the rotation speed of the fan motor 51 . the

(2-7) Also in this embodiment, the pre-start rotational speed detection unit 227 can reliably detect the rotational speed of the fan motor 51 even before the fan motor 51 that is not controlled by the inverter 25 is started. the

(2-8) In the present embodiment as well, the pre-start rotational speed detection unit 27 adopts a simple configuration for detecting the rotational speed of the fan motor 51 before starting based on the induced voltage Vwn generated in the fan motor 51 . the

(2-9) Also in this embodiment, when the fan motor 51 is already rotating due to the influence of wind or the like before starting, the evaporator 14 in the outdoor unit 10 is already turned on as long as its rotation speed is equal to or higher than a predetermined rotation speed. Sufficient air is delivered so that the motor drive control unit 220 does not activate the fan motor 51 . Conversely, if the rotation speed is lower than the predetermined rotation speed, the amount of air supplied to the evaporator 14 in the outdoor unit 10 is insufficient even if the fan motor 51 is rotated, so the motor drive control device 220 starts the fan motor 51 . Therefore, since the starting execution of the fan motor 51 is controlled according to the rotational speed of the fan motor 51 before starting, the power consumption caused by the starting of the fan motor 51 can be suppressed to a minimum. And the performance of the heat pump device installed with the motor drive control device 220 will not be reduced. In addition, since the rotation state immediately before starting is limited, the motor current and the voltage applied to the motor 51 will not increase too much even when external disturbances such as sudden wind blowing are received, and the system 300 will not be damaged by overcurrent or stop due to overvoltage. the

(2-10) The switching unit 229 a switches the signal from the first rotational speed signal FG1 to the second rotational speed signal FG2 when the fan motor 51 is started and the rotor position can be estimated by the sensorless control circuit 28 ongoing. The fact that the sensorless control circuit 28 can estimate the rotor position means that the rotational speed of the fan motor 51 can be estimated from the estimated rotor position, so that the fan motor 51 can be reliably driven without a rotor position sensor. the

(2-11) Also in this embodiment, it is preferable that the signal form of the first rotational speed signal FG1 is the same as that of the second rotational speed signal FG2 . This is because the microcomputer 229 does not need to change the control method according to the rotational speed signal used. the

(2-12) In the present embodiment as well, the microcomputer 229 determines whether or not the sensorless control circuit 228 is abnormal based on the first rotational speed signal FG1 and the second rotational speed signal FG2 . Therefore, the motor drive control device 220 can perform control to immediately stop the fan motor 51 from starting according to the state of the sensorless control circuit 228, and can have high safety. the

(2-13) The motor 51 is a drive source of the outdoor fan 15 which is one of devices included in the outdoor unit 10 of the heat pump apparatus. Therefore, even if the outdoor fan 15 rotates before starting due to the influence of wind or the like, the rotation speed of the fan motor 51 before starting can be easily grasped, and the drive control of the fan motor 51 with high performance can be performed after starting. the

(3) Modifications

(3-1) Modification 2A

In the above-mentioned second embodiment, similarly to Modification 1A of the above-mentioned first embodiment, the sensorless control circuit 228 may force a current for detecting the rotor position to flow through the fan motor 51 being driven, thereby estimating the rotor position. . The rotor position can also be estimated with high precision when using this method. the

(3-2) Modification 2B

In the above-mentioned second embodiment, similarly to Modification 1B of the above-mentioned first embodiment, the pre-start rotational speed detection unit 227 may estimate the rotor position of the fan motor 51 before start, and use the result to perform the pre-start fan motor position. 51 detection of rotational speed. Thereby, even before the fan motor 51 is started, the pre-start rotation speed detection unit 227 can reliably detect the rotation speed of the fan motor 51 . the

(3-3) Modification 2C

In the above-mentioned second embodiment, as in Modification 1C of the above-mentioned first embodiment, the induced voltage used when detecting the rotation speed of the fan motor 51 before starting may be not one phase but two phases or all three phases. . In addition, the U-phase or V-phase induced voltage may be used instead of the W-phase induced voltage Vwn, that is, the detection method is not limited to the above-mentioned second embodiment. the

(3-4) Modification 2D

In the above-mentioned second embodiment, as in the above-mentioned first embodiment, the first rotational speed signal FG1 and the second rotational speed signal FG2 are pulse signals having a period corresponding to the rotational speed of the fan motor 51, or are fixed frequency signals. However, there is a pulse signal having a duty ratio corresponding to the rotation speed of the fan motor 51 . In addition, the first rotation speed signal FG1 and the second rotation speed signal FG2 may be DC voltage signals expressing the rotation speed as a voltage value. the

(3-5) Modification 2E

The motor drive control device 220 of the above-mentioned second embodiment can also be applied to a configuration in which the fan motor 51 and the compressor motor 61 are connected in parallel, as in Modification 1F of the above-mentioned first embodiment. the

(3-6) Modification 2F

In the above-mentioned second embodiment, switching between the first rotational speed signal FG1 and the second rotational speed signal FG2 is performed by the microcomputer 229 , and the fan motor 51 is controlled by the microcomputer 229 . However, a structure may also be adopted in which the rotational speed signal resulting from switching is transmitted to a control unit higher than the microcomputer 229 (a microcomputer or a control circuit not shown, such as an outdoor control unit). the

(3-7) Modification 2G

In addition, in the above-mentioned second embodiment, the switching operation from the first rotational speed signal FG1 to the second rotational speed signal FG2 has been described according to before/after start-up, but even if the driving is stopped once at a predetermined rotational speed, and the Of course, the switching operation of this mode can also be applied to the case of restarting during rotation during deceleration. the

The embodiments and modifications thereof of the present invention have been described above with reference to the drawings, but specific configurations are not limited to these embodiments and modifications thereof, and changes can be made without departing from the gist of the invention. the

Label description

10 outdoor unit; 14 evaporator; 15 outdoor fan; 20 motor drive control device; 21 rectifier; 22 smoothing capacitor; 23 voltage detection part; 24 current detection part; 25 inverter; 26 door drive circuit; 27 speed before starting 28 sensorless control circuit; 29 microcomputer; 30 switching circuit; 51 motor; 100 motor drive control system; 61 compressor motor. the

Prior Art Literature

Patent Documents

Patent Document 1: Japanese Patent Application Laid-Open No. 337080.

Claims (17)

1. a motor drive control device (20), this motor drive control device (20) has:

Prestart rotating speed test section (27), it detects the rotating speed of prestarting motor (51);

No transducer estimation portion (28), the rotor-position of the described motor after it estimates to start in the no-rotor position sensor mode, and estimate described rotating speed of motor according to the described rotor-position that estimates;

Control part (29), the 2nd tach signal (FG2) of the described rotating speed of motor that it is estimated by described no transducer estimation portion (28) by the 1st tach signal (FG1) of the detected described rotating speed of motor of described prestart rotating speed test section (27) or expression according to expression carries out the control of described motor; And

Commutation circuit (30), it imports the change action of the signal of described control part (29), make that described control part is transfused to described the 1st tach signal (FG1) before described electric motor starting, described control part is transfused to described the 2nd tach signal (FG2) behind described electric motor starting.

2. motor drive control device according to claim 1 (20), wherein,

Described prestart rotating speed test section (27), described no transducer estimation portion (28) and described commutation circuit (30) are encapsulated in the integrated circuit package body.

3. a motor drive control device (220), this motor drive control device (220) has:

Prestart rotating speed test section (227), it detects the rotating speed of prestarting motor (51);

No transducer estimation portion (228), the rotor-position of the described motor after it estimates to start in the no-rotor position sensor mode, and estimate described rotating speed of motor according to the described rotor-position that estimates; And

Control part (229), the 2nd tach signal (FG2) of the described rotating speed of motor that it is estimated by described no transducer estimation portion (228) by the 1st tach signal (FG1) of the detected described rotating speed of motor of described prestart rotating speed test section (227) or expression according to expression, carry out the control of described motor

Described control part (229) has switch unit (229a), this switch unit (229a) carries out the change action of employed signal when the described motor of control, make and before described electric motor starting, control described motor according to described the 1st tach signal (FG1), behind described electric motor starting, control described motor according to described the 2nd tach signal (FG2).

4. according to any described motor drive control device (20,220) in the claim 1～3, wherein,

Described no transducer estimation portion (28,228) uses the predetermined Mathematical Modeling relevant with the control of described motor to estimate described rotor-position.

5. according to any described motor drive control device (20,220) in the claim 1～3, wherein,

Described no transducer estimation portion (28,228) estimates described rotor-position by making electric current flow through described motor.

6. according to any described motor drive control device (20,220) in the claim 1～5, wherein,

Described motor drive control device also has to the inverter of described motor supply capability (25,225),

Described no transducer estimation portion (28,228) only carries out the estimation of described rotor-position when carrying out the control of described inverter.

7. according to any described motor drive control device (20,220) in the claim 1～6, wherein,

Described no transducer estimation portion (28,228) can not estimate prestarting described rotating speed of motor.

8. according to any described motor drive control device (20,220) in the claim 1～7, wherein,

Described prestart rotating speed test section (27,227) carries out prestarting described rotating speed of motor and detects under the situation of not using the predetermined Mathematical Modeling relevant with the control of described motor.

9. according to any described motor drive control device (20,220) in the claim 1～8, wherein,

Described prestart rotating speed test section (27,227) detects electric current being flow through carry out prestarting described rotating speed of motor under the situation of described motor.

10. according to any described motor drive control device (20,220) in the claim 1～9, wherein,

Described motor drive control device also has to the inverter of described motor supply capability (25,225),

Even do not carry out the control of described inverter, described prestart rotating speed test section (27,227) also carries out the detection of prestarting described rotating speed of motor.

11. any described motor drive control device (20,220) according to Claim 8～10, wherein,

Described prestart rotating speed test section (27,227) is estimated prestarting described rotor-position, and uses its result to carry out the detection of prestarting described rotating speed of motor.

12. any described motor drive control device (20,220) according to Claim 8～10, wherein,

Described prestart rotating speed test section (27,227) detects prestarting described rotating speed of motor according to the induced voltage that prestart produces in described motor.

13. according to any described motor drive control device (20,220) in the claim 1～12, wherein,

Described control part (29,229) is under the situation of the not enough desired speed of described the 1st tach signal (FG1), described motor is started in the no-rotor position sensor mode, under described the 1st tach signal (FG1) is situation more than the described desired speed, do not make described electric motor starting.

14. according to any described motor drive control device (20,220) in the claim 1～13, wherein,

Described change action to described the 2nd tach signal (FG2) is to carry out under the situation that can estimate described rotor-position by described no transducer estimation portion to signal from described the 1st tach signal (FG1).

15. according to any described motor drive control device (20,220) in the claim 1～14, wherein,

The signal form of described the 1st tach signal (FG1) is identical with the signal form of described the 2nd tach signal (FG2).

16. according to any described motor drive control device (20,220) in the claim 1～15, wherein,

Described control part (29,229) judges that according to described the 1st tach signal (FG1) and described the 2nd tach signal (FG2) described no transducer estimation portion (28,228) has no abnormal.

17. according to any described motor drive control device (20,220) in the claim 1～16, wherein,

Described motor is the drive source of the fan of one of equipment of comprising in the off-premises station as heat pump assembly.

Images