JP3492261B2 - Inverter device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inverter device provided with a drive power source of a charge pump circuit system.

[0002]

2. Description of the Related Art FIG. 16 shows the electrical structure of an inverter device 1 of this type. In FIG. 16, the inverter device 1 is supplied with the DC voltage generated by the DC power supply circuit 2 through the high potential power supply line 3 and the low potential power supply line 4. The DC power supply circuit 2 is connected to each phase bus of an AC power supply 5, which is a three-phase commercial power supply, for example, and a rectifier circuit 12 formed by connecting diodes 6 to 11 in a three-phase bridge connection.
And a smoothing capacitor 13 connected between the high-potential power line 3 and the low-potential power line 4 for smoothing the voltage rectified by the rectifier circuit 12.

The inverter device 1 connected to the DC power supply circuit 2 is constructed as follows. The inverter circuit 14 includes the IGBTs 15-20 and the IGBTs 15-2.
The freewheeling diodes 21 to 26 connected in anti-parallel to 0 are connected in the form of a three-phase bridge between the high-potential power line 3 and the low-potential power line 4, and their output terminals 27u, 27v, 27 are connected.
w are stator windings 28u and 2 of the synchronous motor 28, respectively.
8v and 28w are connected. This synchronous motor 28
The motor (hereinafter referred to as the motor 28) is a so-called permanent magnet electric motor in which a rotor (not shown) is provided with a permanent magnet.
A fan (not shown) is connected as a load to the rotating shaft of the motor 28.

The upper arm drive circuits 29 to 31 for outputting gate drive voltages are connected to the gates of the IGBTs 15 to 17 constituting the upper arm, respectively, and the lower arm I is constituted.
The lower arm drive circuits 32 to 34 that output gate drive voltages are connected to the gates of the GBTs 18 to 20, respectively.

The lower arm drive circuits 32 to 34 commonly have one lower arm drive power supply 35, and the upper arm drive circuits 29 to 31 have charge pump type upper arm drive power supplies 36 to 38, respectively. . The upper arm drive power supplies 36 to 38 are capacitors 39 to 41 for charge pumps, and the charges of the illustrated polarities connected between the positive terminal of the lower arm drive power supply 35 and the positive terminals of the capacitors 39 to 41, respectively. Pump diode 42
It consists of ~ 44. And IGB of the lower arm
When T18 to 20 are turned on, the capacitors 39 to 41 are
Each is charged from the positive side terminal of the lower arm drive power supply 35 through the diodes 42 to 44.

Induced voltage detection circuit 45 (see FIGS. 2 and 3)
Inputs the terminal voltages Vu, Vv, Vw of the motor 28,
The IGBTs 15 to 20 are off (that is, the motor 28
Is a free run state), the terminal voltages Vu, Vv, V
A substantially sinusoidal induced voltage appearing in w is detected, and the phase signals SA and SB of the rotor of the motor 28 are output. Further, the control circuit 46 uses the induced voltage detection circuit 4
The phase signals SA and SB are input from 5 to detect the phase, and the drive of the motor 28 is started based on the detected phase.

In the inverter device 1 having the charge pump type upper arm drive power sources 36 to 38, the charge pump capacitors 39 to 41 are connected to the IGBTs 15 to 41 when the power is turned on or when power is restored from a power failure.
Not enough charge to drive 17. Therefore, as disclosed in, for example, Japanese Unexamined Patent Publication (Kokai) No. 7-15978, before the drive of the motor 28 is started, the IG of the upper arm
IGBT of the lower arm with BT15-17 turned off
18 to 20 are turned on to charge the capacitors 39 to 41.

[0008]

By the way, the motor 28
When the fan attached to the rotating shaft of the
Alternatively, if the AC power supply 5 fails during the drive of the motor 28 by the inverter device 1, the motor 28 is in a rotating state (free-run state) even though the IGBTs 15 to 20 are all in the OFF state. In this free-run state, when the operation start command ST is input to the control circuit 46 or the AC power supply 5 is restored, the inverter device 1 starts driving the motor 28.

In this case, the inverter device 1 is arranged so that the motor 28 can be brought into a synchronized state immediately after the start of driving.
It is necessary to detect the phase and rotation speed (including the rotation direction) of the rotor of the motor 28 in advance, and apply the gate drive voltage synchronized with the motor 28 to the gates of the IGBTs 15-20.

However, in order to detect these phases and rotational speeds, the induced voltage detection circuit 45 detects the terminal voltages Vu and V.
Since this is performed by detecting the induced voltage appearing in v and Vw, all the IGBTs 15 to 20 must be kept in the off state during the detection period. That is, during the detection period, the capacitors 39 to 41 cannot be charged by the charge pump operation described above.

Therefore, so far, any one of the following means has been used to detect the phase and the rotation speed and the capacitors 39 to
41 was being charged. The first means is a means for detecting the rotation speed and the phase after charging the capacitors 39 to 41 by the charge pump operation. According to this means, the motor 28 can be driven immediately after the detection of the phase by detecting the phase after the detection of the rotation speed, the phase error at the start of the drive is reduced, and the synchronous pull-in of the motor 28 is relatively performed. It will be easy.

However, the phase can be detected, for example, by an electrical angle of 6
The rotation speed is detected by detecting the edges of the phase signals SA and SB that appear every 0 ° or 120 °.
For example, it is performed by measuring the time of one cycle of the phase signals SA and SB. Therefore, especially at a low rotation speed, the detection time becomes long, and there is a possibility that the electric charges of the capacitors 39 to 41 are discharged between the charging of the capacitors 39 to 41 and the start of driving the motor 28.

The second means is means for charging the capacitors 39 to 41 by the charge pump operation after detecting the rotational speed and the phase. According to this means, the motor 28 can be driven immediately after charging the capacitors 39 to 41, so that the upper arm IGBTs 15 to 17 can be driven reliably. However, since it takes time from the detection of the rotational speed and the phase to the start of driving the motor 28,
Due to the rotation of the motor 28, an error occurs in the rotation speed and phase at the start of driving, which makes it difficult to pull in the motor 28 in synchronization.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a drive power source of a charge pump system so that a charge pump capacitor can be sufficiently charged at the start of driving of an electric motor. Another object of the present invention is to provide an inverter device that can be reliably synchronized with an electric motor.

[0015]

In order to achieve the above object, an inverter device according to a first aspect of the present invention is a motor drive comprising an upper arm switching element and a lower arm switching element connected in series between DC power supply lines. Inverter circuit, an upper arm drive circuit for driving the upper arm switching element, a lower arm drive circuit for driving the lower arm switching element, and a lower arm drive for supplying a driving DC voltage to the lower arm drive circuit A power supply and a charge pump capacitor for supplying a driving DC voltage to the upper arm drive circuit are provided, and the lower arm drive power supply charges the charge pump capacitor when the lower arm switching element is in the ON state. Upper arm drive power supply, and drive for the upper arm drive circuit and the lower arm drive circuit Composed of a control means for outputting a degree.

The control means detects the phase of the rotor of the electric motor at least before driving the electric motor, and until it determines that the phase detection by the phase detecting means is completed. Phase detection end determination means for causing the phase detection means to periodically perform a detection operation, and drive start control for starting drive of the electric motor in response to the phase detection end determination means determining that the phase detection is completed. Means and the phase detection end determination means determines that the detection of the phase is completed, the charging operation of the charge pump capacitor is cyclic and during the non-execution of the phase detection operation by the phase detection means. Charging control means for generating the drive signal so as to be performed.

According to this configuration, when the control means outputs the ON drive signal to the lower arm drive circuit to turn ON the lower arm switching element, the lower arm drive power source changes the upper arm drive power source through the lower arm switching element. The charge pump capacitor is charged, and the upper arm drive circuit can drive the upper arm switching element by this charge.

In addition, the electric motor is
When the load receives an external force (such as wind pressure) or when a power failure occurs during rotational driving, the motor is in a rotating state. Even in this case, the control means detects the phase of the rotor before starting the driving of the electric motor, and therefore, based on the phase and the rotational speed of the electric motor detected before that, for example, the electric motor is started at the start of driving. Can be synchronized with.

The phase detecting means periodically executes the phase detecting operation until the phase detection is completed, and the drive start control means starts the drive of the electric motor in response to the completion of the phase detection. The time from the end of phase detection to the start of driving the electric motor is shortened, the phase error at the start of driving is reduced, and synchronization with the electric motor is facilitated.

Further, since the charge control means executes the charging operation of the charge pump capacitor so as not to be simultaneously performed with the phase detection operation by the phase detection means, the charge pump capacitor can be charged without disturbing the phase detection operation. Moreover, since the charging operation is performed periodically,
The time from the charge of the charge pump capacitor to the start of driving the motor is shortened, and sufficient charge is accumulated in the charge pump capacitor at the start of driving. As a result, the upper arm drive circuit can reliably drive the upper arm switching element.

According to a second aspect of the present invention, the control means of the inverter device has a rotation speed detecting means for detecting the rotation speed of the electric motor at least before the driving of the electric motor, and the detection of the rotation speed by the rotation speed detecting means is completed. Until the determination is made, the rotation speed detection end determination means for causing the rotation speed detection means to periodically perform the detection operation, and the rotation speed detection completion determination means determines that the detection of the rotation speed is completed. Drive start control means for starting the drive of the electric motor and until the rotation speed detection end determination means determines that the rotation speed has been detected, the charging operation of the charge pump capacitor is cyclic and Charging control means for generating the drive signal so as to be performed during non-execution of the rotation speed detection operation by the rotation speed detection means. And said that you are.

According to this configuration, for example, when the driving is started from the state where the electric motor is rotating, the control means detects the rotational speed of the rotor before the driving of the electric motor is started. Based on the detected phase of the rotor of the electric motor before that, it is possible to synchronize with the electric motor at the start of driving.

The rotation speed detection means periodically executes the rotation speed detection operation until the rotation speed detection is completed, and the drive start control means drives the electric motor in response to the completion of the rotation speed detection. Since it starts, the time from the end of rotation speed detection to the start of driving the electric motor is shortened, the rotational speed error at the start of driving is reduced, and synchronization with the electric motor is facilitated.

Further, since the charging control means executes the charging operation of the charge pump capacitor so as not to operate simultaneously with the rotation speed detecting operation, the charge pump capacitor can be charged without disturbing the rotation speed detecting operation. Moreover, since the charging operation is performed periodically, the time from the charging of the charge pump capacitor to the start of driving the electric motor is shortened.

According to a third aspect of the present invention, the control means of the inverter device includes the phase detection means, the rotation speed detection means, the phase detection end determination means, the rotation speed detection end determination means, and the phase detection end determination means. Drive end control means for starting the drive of the electric motor in response to determining that the rotation speed detection end determination means has ended detection of the rotation speed, and the phase detection end determination means. Until the rotation speed detection end determination means determines that the rotation speed detection has ended, the charging operation of the charge pump capacitor is cyclic and the phase detection means Charging for generating the drive signal so as to be performed during non-execution of the phase detection operation by the rotation speed detection means and the rotation speed detection operation by the rotation speed detection means. Characterized in that it is constituted by a control means.

According to this configuration, for example, when the driving is started from the state where the electric motor is rotating, the control means detects the phase and the rotation speed of the rotor before the driving of the electric motor is started. Sometimes it can be synchronized with the motor. Further, the phase detection operation and the rotation speed detection operation are periodically executed, and the drive of the electric motor is started in response to the completion of the detection of the phase and the rotation speed. It becomes smaller and easier to synchronize with the electric motor.

Further, the charge pump capacitor can be charged without disturbing the phase detection operation and the rotation speed detection operation. Moreover, since the charging operation is performed periodically, the time from the charging of the charge pump capacitor to the start of driving the electric motor is shortened.

When the phase detecting means is provided, the control means is
It is preferable to include a phase correction unit that corrects the phase of the rotor of the electric motor detected by the phase detection unit (claim 4). With this configuration, it is possible to correct a phase error that occurs due to a time delay from the time of detecting the phase to the start of energization of the winding of the electric motor, and it is possible to reliably synchronize with the electric motor at the start of driving. .

Further, the phase detection end determination means determines that the phase detection is completed when the number of times the charging operation of the charge pump capacitor is executed reaches a predetermined number before the phase detection means completes the phase detection. It is preferable (Claim 5). According to this configuration, the time required to start driving is limited, and the driving start is not extremely delayed even when the electric motor is stopped before starting the driving or is rotating at a low rotation speed. .

When the rotation speed detecting means is provided, the control means preferably comprises rotation speed correcting means for correcting the rotation speed of the electric motor detected by the rotation speed detecting means (claim 6). With this configuration, it is possible to correct a rotation speed error that occurs due to a time delay between the time when the rotation speed is detected and the time when the power is supplied to the winding of the electric motor, and it is possible to reliably synchronize with the electric motor when the driving is started. it can.

Further, the rotation speed detection end determination means terminates the detection of the rotation speed when the number of executions of the charge pump capacitor charging operation reaches a predetermined number before the rotation speed detection means ends the rotation speed detection. It is preferable to determine that it is (claim 7). According to this configuration,
The time required until the start of driving is limited, and even if the electric motor is stopped before the start of driving or is rotating at a low rotational speed, the start of driving is not extremely delayed.

Further, when the phase detecting means and the rotational speed detecting means are provided, it is preferable that the control means includes the phase correcting means and the rotational speed correcting means (claim 8).
According to this configuration, both the phase error and the rotational speed error can be corrected, and more reliable synchronization with the electric motor can be achieved.

In this case as well, the phase detection end determination means and the rotation speed detection end determination means end the detection when the number of times the charging operation of the charge pump capacitor has been performed reaches a predetermined number before the detection ends. It is preferable to determine that (Claim 9). According to this configuration,
There is a limit on the time required to start driving.

In each of the above means, it is preferable that the control means determines the charging operation time of the charge pump capacitor based on a time interval for performing the charging operation of the charge pump capacitor (claim 10). According to this configuration, even when the interval of the charging operation of the charge pump capacitor changes, the charge of the charge pump capacitor does not run short.

Further, in each of the above means, a charging voltage detecting means for detecting the charging voltage of the charge pump capacitor is provided, and the charging control means is based on the charging voltage detected by the charging voltage detecting means, and the charge pump It is preferable to determine the charging operation time of the capacitor (claim 11).

According to this structure, for example, when the charging voltage of the charge pump capacitor is high, the charging operation time becomes short, and when the charging voltage of the charge pump capacitor is low, the charging operation time becomes long. As a result, the charge voltage of the charge pump capacitor is maintained at a value sufficient for driving.

Further, it is preferable that the charging control means generate the drive signal by PWM control (claim 12). According to this configuration, the drive signal has a repetitive waveform of an on pulse and an off pulse having a short time width. On the other hand, when the lower arm switching element is switched from ON to OFF while the motor is rotating, the current flowing through the lower arm switching element at the time of ON flows back to the DC power source by flowing back through the upper arm switching element. Increase the voltage between the lines (boosting action). According to the above configuration, since the ON pulse width is narrow, this boosting action can be suppressed, and the occurrence of overvoltage of the DC voltage can be prevented in advance.

In this case, the charge control means preferably determines the duty ratio of the drive signal based on the rotation speed of the electric motor (claim 13). This makes it possible to charge the charge pump capacitor while suppressing the boosting action regardless of the rotation speed of the electric motor.

Further, it is preferable that the charging control means determines the PWM frequency of the drive signal based on the rotation speed of the electric motor (claim 14). As a result, the charge pump capacitor can be charged while suppressing the boosting action regardless of the rotation speed of the electric motor.

Further, when the drive signal has a PWM waveform, it is preferable that the charging control means determines the time width of the drive signal based on the rotation speed of the electric motor (claim 15). According to this configuration, the time width of the drive signal is determined according to the variable setting of the duty ratio of the drive signal, the PWM frequency, etc. Therefore, it is possible to prevent the charge pump capacitor from being insufficiently charged.

In each of the above-mentioned means, it is preferable that the charge control means stops the detection operation for a predetermined period after executing the charging operation of the charge pump capacitor (claim 16). According to this configuration, since the detection operation is executed after the lower arm switching element is completely turned off and the boosting action disappears, erroneous detection of phase and rotational speed is eliminated.

[0042]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) A first embodiment (corresponding to claim 3) of the present invention will be described below with reference to FIGS.
Will be described with reference to. FIG. 1 shows an inverter device 51.
16 shows the electrical configuration thereof, and the same components as those in FIG. 16 are denoted by the same reference numerals. Here, the high potential power supply line 3 and the low potential power supply line 4 correspond to the DC power supply line in the present invention,
IGBTs 15 to 17 are upper arm switching elements, IG
The BTs 18 to 20 correspond to the lower arm switching element.

The control circuit 52 corresponding to the control means is mainly composed of a microcomputer, and its main functions are shown as functional blocks in FIG. High-level or low-level phase signals SA and SB output from the induced voltage detection circuit 45, which will be described in detail later, are input to both the phase detection unit 53 and the rotation speed detection unit 54 in the control circuit 52.

The phase detecting section 53 as the phase detecting means is
The levels of the phase signals SA and SB are sampled at predetermined sampling intervals, and the levels are detected by the phase detection end determination unit 5
It is designed to output to 5. Further, the rotation speed detecting section 54 as the rotation speed detecting means samples the levels of the phase signals SA and SB at a predetermined sampling interval,
The level is output to the rotation speed detection end determination unit 56.

The phase detection end determination unit 55 as the phase detection end determination unit and the charge control unit determines whether the levels of the phase signals SA and SB input from the phase detection unit 53 have changed, that is, whether the phase detection has been completed. The determination is made and the determination result is output to the drive start control unit 57. Further, the phase detection end determination unit 55 performs a charge pump operation on the drive control unit 58 before the end of phase detection when the phase detection unit 53 and the rotation speed detection unit 54 are not sampling the phase signals SA and SB. A drive signal for performing the operation is output, and when the phase detection is completed, the detected phase is output to the drive control unit 58.

The rotation speed detection end determination unit 56 and the rotation speed detection end determination unit 56 as the rotation speed detection end determination unit detect the rotation speed detection by detecting the level change of the phase signals SA and SB input from the rotation speed detection unit 54. It is determined whether or not the determination is made, and the determination result is output to the drive start control unit 57. Further, the rotation speed detection end determination unit 56 instructs the drive control unit 58 to charge the pump before the end of the rotation speed detection when the phase detection unit 53 and the rotation speed detection unit 54 are not sampling the phase signals SA and SB. A drive signal for performing the operation is output, and when the detection of the rotation speed is completed, the detected rotation speed is set to the drive control unit 58.
It is designed to output to.

The drive start control unit 57 as the drive start control means receives the determination results of the phase detection end and the rotation speed detection end from the phase detection end determination unit 55 and the rotation speed detection end determination unit 56, respectively. A drive start command is output to 58.

The drive control unit 58 receives the drive start command from the drive start control unit 57 before the phase detection end determination unit 5 is operated.
5 and the drive signals from the rotation speed detection end determination unit 56 are output to the drive circuits 29 to 34. Further, the drive control unit 58, after inputting the drive start command from the drive start control unit 57, generates a drive signal using the detected phase and rotation speed, and thereafter until the operation start command ST stops or The drive signal is continuously generated by V / F control or the like until a power failure occurs.

The inverter device 51 includes a power failure detection circuit 59 for detecting a power failure (including an instantaneous power failure) of the AC power supply 5.
Is provided. The power failure detection circuit 59 outputs a power failure detection signal to the control circuit 52 when a power failure is detected.

FIG. 2 shows the electrical configuration of the induced voltage detection circuit 45. Divided terminal voltages Vu, Vv, Vw
Between the terminals Tu, Tv, and Tw to which the power supply line VP is input and the power supply line VP, the diodes Dup, Dvp, and Dwp are connected with the power supply line VP side as a cathode, respectively.
Between the v and Tw and the ground line GND, the diodes Dun and D with the ground line GND side as the anode are respectively provided.
vn and Dwn are connected. In addition, terminals Tu and T
Capacitors Cu, Cv, and Cw are connected between v and Tw and the ground line GND, respectively.

A resistor R1 is connected between the output terminal of the comparator CMP1 and the non-inverting input terminal, the output terminal is connected to the terminal T1 (output terminal of the phase signal SA), and the power supply line is also connected via the resistor R2. It is connected to the VP.
The non-inverting input terminal and the inverting input terminal of the comparator CMP1 are connected to the terminals Tv and Tu, respectively.
Similarly, a resistor R3 is connected between the output terminal of the comparator CMP2 and the non-inverting input terminal, the output terminal is connected to the terminal T2 (output terminal of the phase signal SB), and the power line via the resistor R4. It is connected to the VP. Further, the non-inverting input terminal and the inverting input terminal of the comparator CMP2 are connected to the terminals Tv and Tw, respectively. The power supply terminals of the comparators CMP1 and CMP2 are connected to the power supply line VP and the ground line GND.

Next, the operation when the inverter device 51 starts driving the motor 28 while the motor 28 is rotating in the free-run state, that is, the non-driving state, will be described with reference to FIGS. 3 and 4. .

First, when the inverter device 51 is driving the motor 28, the phase detection end determination unit 55 and the rotation speed detection end determination unit 56 cause the drive control unit 58 to perform the drive signal for performing the charge pump operation. Stop the output of. When the drive control unit 58 receives the drive start command from the drive start control unit 57, the drive control unit 58 performs V / F control according to a speed command signal (not shown), and PWs the drive circuits 29 to 34.
An M-controlled drive signal is output. And the drive circuit 2
9 to 31 output the gate drive voltage to the IGBTs 15 to 17 using the voltages charged in the capacitors 39 to 41 as power supply voltages, and the drive circuits 32 to 34 use the lower arm drive power supply 35 as the operation power supply to the IGBTs 18 to 20. Outputs the gate drive voltage. As a result, the motor 28 rotates in synchronization with the AC voltage output by the inverter device 51.

In this drive state, when the IGBTs 18 to 20 on the lower arm side are turned on in accordance with the PWM controlled drive signal, the capacitors 39 to 41 are charged from the positive side terminals of the lower arm drive power supply 35 through the diodes 42 to 44, respectively. To be done.

Now, for example, when the AC power supply 5 fails during the driving of the motor 28, the control circuit 52 and the power failure detection circuit 59 continue to operate for a while until the control power supply voltage drops. Then, the power failure detection circuit 59 outputs a power failure detection signal to the control circuit 52. When the control circuit 52 receives the power failure detection signal, it outputs an off drive signal to the drive circuits 29 to 34 to put the motor 28 in the free run state. During this free-run state, the IGBT1 on the lower arm side
8 to 20 keep turning off, so the upper arm drive power supply 36 to
38, the charge pump operation is stopped. Therefore, the voltage of the capacitors 39 to 41 gradually decreases, and eventually becomes a voltage insufficient for the operation of the drive circuits 29 to 31.

After that, when the AC power supply 5 is restored, the inverter device 51 restarts the driving of the motor 28 rotating in the free-run state according to the flowchart shown in FIG. That is, when the power failure detection signal from the power failure detection circuit 59 stops due to power recovery, the control circuit 52 outputs the ON drive signal to the lower arm drive circuits 32 to 34 all at once, and charges the upper arm drive power supplies 36 to 38. A pump operation is performed to charge (main charge) the capacitors 39 to 41 (step S1). After this charging, the control circuit 52 outputs the OFF drive signals to the lower arm drive circuits 32 to 34 all at once, and turns off all the IGBTs 15 to 20.

Subsequently, the control circuit 52 (specifically, the rotation speed detection unit 54 shown in FIG. 1) samples the levels of the phase signals SA and SB from the induced voltage detection circuit 45 in order to detect the rotation speed. Yes (step S2).

FIG. 3 shows the induced voltage and phase signals SA, S.
The waveform of B is shown. Both of the phase signals SA and SB invert the level every 180 ° in electrical angle, and the level inversion occurs in either of the phase signals SA and SB at intervals of 60 ° or 120 ° in electrical angle. Therefore, the rotational speed can be obtained by detecting the edge of either one of the phase signals SA and SB (referred to as the phase signal SA in the following description) and measuring the edge interval.

Now, the control circuit 52 (specifically, the rotation speed detection end judging section 56 shown in FIG. 1) is controlled by the step S in FIG.
In 3, the presence or absence of a level change (that is, an edge) of the phase signal SA is detected, and when an edge is detected, it is determined whether the time measurement of the edge interval is completed, that is, the detection of the rotation speed is completed. Rotational speed detection end determination unit 56
Determines that the detection is not completed (“NO”), the process proceeds to step S4, and a drive signal for performing the charge pump operation is given to the drive control unit 58. The drive controller 58 controls the lower arm drive circuit 3 in the same manner as the main charge.
An on-drive signal is output to all the capacitors 2 to 34 at the same time, and the capacitors 39 to 41 are charged for a predetermined time. After charging,
The control circuit 52 moves to step S2.

On the other hand, when the control circuit 52 determines in step S3 that the detection is completed ("YES"), step S5.
Then, the rotation speed is obtained from the measured edge interval.
Then, in step S6, the control circuit 52 performs a calculation based on the V / F control using the obtained rotation speed to obtain the voltage to be output from the inverter device 51.

The time required to detect the rotational speed, that is, the execution time of steps S2 and S3 is determined by the capacitor 39
The charges of ~ 41 are set to be shorter than the time until the charges are discharged below a voltage sufficient to drive the IGBTs 15-17.

Subsequently, the control circuit 52 controls the phase (motor 28
The position of the rotor is detected. The control circuit 52 (specifically, the phase detection unit 53 shown in FIG. 1) detects the phase by detecting the phase signal SA from the induced voltage detection circuit 45.
The SB level is sampled (step S7).

The control circuit 52 (specifically, the phase detection end determining section 55 shown in FIG. 1) determines whether or not a level change (that is, an edge) of the phase signal SA or SB is detected in step S8. As shown in FIG. 3, the edge has 90 °, 150 °, 270 ° and 330 ° electrical angles with respect to the rotor.
It occurs when the phase becomes.

If the phase detection end determination unit 55 determines that the phase detection is not completed (“NO”), the process proceeds to step S9, and a drive signal for performing the charge pump operation is given to the drive control unit 58. . The drive control unit 58 charges the capacitors 39 to 41 for a predetermined time as in step S4. After completion of charging, the control circuit 52 moves to step S7.

On the other hand, the control circuit 52 (phase detection end determination section 55) ends the detection in step S8 ("YE
S "), the process proceeds to step S10 to obtain the phase based on the detected edge. This phase is output to the drive controller 58. Then, in step S11,
Control circuit 52 (specifically, drive start control unit 5 shown in FIG. 1)
7) outputs a drive start command to the drive control unit 58. The drive control unit 58 outputs a drive signal synchronized with the motor 28 to the drive circuits 29 to 34 based on the detected rotation speed, phase and output voltage. As a result, the inverter device 51 can re-drive the motor 28 that is rotating in the free-run state due to the power failure from the rotating state. After the driving is started, the phase detection and the rotation speed detection of the rotor may be appropriately executed (not detected in this embodiment).

The time required to detect the phase, that is, the execution time of steps S7 and S8, depends on the capacitors 39-4.
The electric charge of 1 is set to be shorter than the time until it is discharged to a voltage equal to or lower than the voltage sufficient to drive the IGBTs 15 to 17.

As described above, according to the inverter device 51 of the present embodiment, the control circuit 52 detects the edges of the phase signals SA and SB output from the induced voltage detection circuit 45 before starting driving. , The rotation speed of the motor 28 and the phase of the rotor are detected. Then, since the drive signal of the motor 28 is generated using the detection results, it becomes possible to perform the synchronous operation even from the start of the drive even for the motor 28 rotating in the free-run state.

Therefore, as shown in this embodiment, when power is restored from the power failure that occurred during driving, or when wind pressure is applied to the load (fan in this embodiment) and the motor 28 is rotating due to the wind pressure. Motor 28
Can be immediately driven from its rotating state without being temporarily stopped.

Until the detection of the rotation speed is completed, the rotation speed detection operation and the charge pump capacitors 39 to 41 charging operation are alternately and periodically executed. The capacitors 39 to 41 can be charged without disturbing the operation. Further, thereafter, the phase detection operation and the charging operation of the charge pump capacitors 39 to 41 are alternately and periodically executed until the phase detection is completed, so that the phase detection operation is disturbed. Instead, the capacitors 39 to 41 can be charged.

Then, as soon as the detection of the phase ends, the driving of the motor 28 is started, so that the capacitors 39-4
The time from the charging operation of No. 1 to the start of driving is shortened, and the capacitors 39 to 41 can be sufficiently charged at the start of driving. Further, in this embodiment, the rotation speed is detected first, and then the phase is detected. In the free-run state, the change in rotation speed is relatively gradual, but the phase changes momentarily according to the rotation speed at that time.Therefore, by executing the phase detection immediately before the start of driving, the drive start The phase error at the time can be reduced, and the synchronization with the motor 28 can be easily achieved.

(Second Embodiment) Next, a second embodiment of the present invention (corresponding to claim 1) will be described with reference to FIGS. 5 and 6. FIG. 5 shows an electrical configuration of the inverter device 60. The inverter device 60 is different from the inverter device 51 shown in FIG. 1 in the configurations of a control circuit 61, specifically, a rotation speed detection end determination unit 62 and a drive start control unit 63.

The rotation speed detection end determination unit 62 measures the edge interval of the phase signal SA or SB input from the rotation speed detection unit 54 until it determines that the rotation speed detection is completed. Unlike the rotation speed detection end determination unit 56, the rotation speed detection end determination unit 62 does not execute the charge pump operation during the detection operation. In addition, the drive start control unit 6
3 receives the determination result from the phase detection end determination unit 55 and gives a drive start command to the drive control unit 58.

FIG. 6 is a flowchart showing the rotational speed and phase detection operation executed by the control circuit 61. Hereinafter, the control content when the inverter device 60 starts driving the motor 28 that is in the free-run state due to a power failure or the like will be described with reference to FIG.

The control circuit 61 (specifically, the rotation speed detection unit 54 and the rotation speed detection end determination unit 62 shown in FIG. 5) detects the rotation speed in step S21. During this detection, the control circuit 61 does not perform the charge pump operation.
After that, the control circuit 61 obtains the rotation speed from the edge interval measured in step S21 (step S22), and calculates the output voltage (step S23). After that, the control circuit 61 charges the capacitors 39 to 41 (main charge) (step S24).

Subsequently, the control circuit 61 starts from step S25.
In S27, the phase detection operation and the charging operation of the capacitors 39 to 41 are alternately and periodically executed until the phase detection is completed. Then, in step S29, the control circuit 61 (specifically, the drive start control unit 63 shown in FIG. 5) outputs a drive start command to the drive control unit 58.

Also according to this embodiment, the rotation speed and the phase are detected before the driving is started, and the detection result is used for the motor 2
Since the drive signal of No. 8 is generated, the motor 28 in the free run state can be synchronously operated from the start of driving. In this case, the control circuit 61 executes the main charge after detecting the rotational speed which is relatively moderately changed, and thereafter alternately and periodically executes the phase detecting operation and the charging operation of the capacitors 39 to 41. Therefore, at the start of driving, a rotational speed with a relatively small error and an accurate phase can be obtained, and the charging voltage of the capacitors 39 to 41 is set to the IGBT 15.
The voltage is sufficient to drive ~ 17.

(Third Embodiment) Next, a third embodiment of the present invention (corresponding to claim 2) will be described with reference to FIGS. 7 and 8. FIG. 6 shows an electrical configuration of the inverter device 64. The inverter device 64 differs from the inverter device 51 shown in FIG. 1 in the configuration of the control circuit 65, specifically, the phase detection end determination unit 66 and the drive start control unit 67.

The phase detection end determination unit 66 changes the level (edge) of the phase signals SA and SB input from the phase degree detection unit 53 until it determines that the phase detection is completed.
To detect. Unlike the phase detection end determination unit 55, the phase detection end determination unit 66 does not execute the charge pump operation during the detection operation. Further, the drive start control unit 67 receives the detection determination result from the rotation speed detection end determination unit 56 and gives a drive start command to the drive control unit 58.

FIG. 8 is a flow chart showing the rotational speed and phase detection operation executed by the control circuit 65. Hereinafter, the control content when the inverter device 64 starts driving the motor 28 that is in the free-run state due to a power failure or the like will be described with reference to FIG.

The control circuit 65 (specifically, the phase detection section 53 and the phase detection end determination section 66 shown in FIG. 7) is operated in step S
At 31, the phase of the rotor is detected. During this detection
The control circuit 65 does not perform the charge pump operation. After that, the control circuit 65 obtains the phase based on the edge detected in step S31 (step S32). afterwards,
The control circuit 65 charges the capacitors 39 to 41 (main charge) (step S33).

Subsequently, the control circuit 65 starts from step S34.
In S38, until the detection of the rotation speed is completed,
The operation of detecting the rotation speed and the operation of charging the capacitors 39 to 41 are alternately and periodically executed. And step S
In 39, the control circuit 65 (specifically, the drive start control unit 67 shown in FIG. 5) outputs a drive start command to the drive control unit 58.

Also in this embodiment, the phase and the rotation speed are detected before the start of driving, and the motor 2 is detected by using the detection result.
Since the drive signal of No. 8 is generated, the motor 28 in the free run state can be synchronously operated immediately after the start of driving. In this case, the control circuit 65 executes the main charge after detecting the phase, and then performs the rotation speed detection operation and the capacitor 3
The charging operations 9 to 41 are alternately and periodically executed.
Therefore, at the start of driving, the phase and the accurate rotation speed are obtained, and the charging voltage of the capacitors 39 to 41 becomes a voltage sufficient to drive the IGBTs 15 to 17.

(Fourth Embodiment) Next, a fourth embodiment of the present invention (corresponding to claim 9) will be described with reference to FIG. 9 showing an electrical configuration of an inverter device. The inverter device 68 shown in FIG. 9 corresponds to the inverter device 5 shown in FIG.
1, the configuration of the control circuit 69, specifically, the phase detection end determination unit 70 and the rotational speed detection end determination unit 71 is different.

The phase detection end determination unit 70 (corresponding to the phase detection end determination unit and the charge control unit) is provided in the phase detection unit 53.
At the same time, the phase detection operation and the charging operation of the capacitors 39 to 41 are alternately and periodically executed (see steps S7 to S9 in FIG. 4). In this case, the phase detection end determination unit 7
0 (specifically, the limiter 70a shown in FIG. 9) counts the number of charging operations of the capacitors 39 to 41 (the number of executions of step S9 in FIG. 4), and the level change of the phase signal SA or SB is detected. Even if not
When the counted number of charging operations reaches a predetermined value, it is determined that the phase detection operation is completed (corresponding to step S8).

The rotation speed detection end determination unit 71 (corresponding to the rotation speed detection end determination unit and the charging control unit), together with the rotation speed detection unit 54, alternately performs the rotation speed detection operation and the charging operation of the capacitors 39 to 41. It is also executed periodically (see steps S2 to S4 in FIG. 4). In this case, the rotation speed detection end determination unit 71 (specifically, the limiter 71a shown in FIG. 9) counts the number of charging operations of the capacitors 39 to 41 (the number of executions of step S4 in FIG. 4), and Phase signal SA (or S
Even if the edge spacing in B) is not measured,
When the counted number of charging operations reaches a predetermined value, it is determined that the rotational speed detecting operation is completed (step S
Equivalent to 3.).

The state in which the level change of the phase signal SA or SB is not detected while the charging operation is repeated a predetermined number of times is the state in which the motor 28 is stopped or the state in which the motor 28 is rotating at an extremely low rotation speed. According to the inverter device 68 of the present embodiment, since it is not necessary to wait for a change in the level of the phase signal SA or SB, particularly in the stop state or the low rotation speed state, the power recovery from the input of the operation start command ST or the power failure At times, the time until the motor 28 is actually driven can be shortened. Even in this case, since the charging operation of the capacitors 39 to 41 is performed a predetermined number of times, the charging voltage at the start of driving becomes a voltage sufficient for driving the IGBTs 15 to 17.

Further, when the control circuit 69 cannot detect the level change of the phase signal SA or SB, the control circuit 69 determines that the motor 28 is in the stopped state or the low rotation speed state, and changes the frequency of the output voltage from the low frequency. Control to increase gradually. Therefore, even if the phase and the rotation speed cannot be detected, the motor 28 can be brought into the synchronized state.

(Fifth Embodiment) Next, a fifth embodiment of the present invention (corresponding to claims 10 and 11) will be described with reference to FIGS.
This will be described with reference to 1. FIG. 10 shows an inverter device 7
2 shows an electrical configuration of the inverter device 51 (see FIG. 1), and the configuration of the control circuit 73, specifically, the phase detection end determination unit 74 and the rotation speed detection end determination unit 75 is different. Although not shown, the capacitor 39 is provided with a charging voltage detector for detecting its charging voltage, and the detected charging voltage is applied to the control circuit 73.

The charging operation time control unit 74a of the phase detection end judgment unit 74 (corresponding to the phase detection end judgment unit and the charging control unit) determines the charging operation time of the capacitors 39 to 41 (execution time of step S9 in FIG. 4). The time interval between the charging operation and the charging operation, that is, the time from the end of the execution of step S9 to the start of the next execution of step S9 and the charging voltage are determined.

The charging operation time control unit 75a of the rotation speed detection end judgment unit 75 (corresponding to the rotation speed detection end judgment unit and the charging control unit) is also the charging operation time control unit 74a.
The charging time is determined in the same manner as.

FIG. 11 shows the charging operation time control units 74a and 7a.
5a shows the control characteristic of the charging operation time by 5a. Figure 1
1 (a) shows the relationship between the charging operation time interval (horizontal axis) and the charging operation time (vertical axis), and FIG. 11 (b) shows the charging voltage (horizontal axis) and charging operation time (vertical axis). Shows the relationship with.

That is, since the voltage drop of the capacitors 39 to 41 increases as the charging operation time interval increases, the charging operation time control units 74a and 75a control the charging operation to increase in proportion to the time interval. To do. In addition, the charging operation time control units 74a and 75a perform control such that the lower the detected value of the charging voltage is, the longer the charging operation is. As a result, the charging voltage of the capacitors 39 to 41 can be set to a voltage sufficient for driving at the start of driving.

Although the control circuit 73 is configured to control the charging operation time based on the charging operation time interval and the charging voltage, it is configured to control the charging operation time based on only one of them. You may. Further, the phase detection end determination unit 74 and the rotation speed detection end determination unit 75 may include the limiter described above.

(Sixth Embodiment) Next, a sixth embodiment of the present invention (corresponding to claims 12 to 15) will be described with reference to FIGS. 12 and 13. FIG. 12 shows an electrical configuration of the inverter device 76.
In contrast to (see FIG. 1), the control circuit 77, specifically, the configurations of the phase detection end determination unit 78 and the rotation speed detection end determination unit 79 are different.

PWM control section 78 of phase detection end determination section 78 (corresponding to phase detection end determination means and charge control means)
a is PWM for the drive signal output to the drive control unit 58.
It is a circuit that controls. Similarly, the PWM control unit 79 a of the rotation speed detection end determination unit 79 (corresponding to the rotation speed detection end determination unit and the charging control unit) is a circuit that performs PWM control on the drive signal output to the drive control unit 58.

These PWM control units 78a and 79a control the PWM frequency, duty ratio and time width (time corresponding to the charging operation time in the fifth embodiment) of the PWM drive signal according to the rotation speed of the motor 28. It has become. FIG. 13 shows this control characteristic.
The control units 78a and 79a set the PWM frequency higher, the duty ratio smaller, and the time width longer as the rotation speed of the motor 28 increases.

At the end of the charge pump operation, that is, when the lower arm IGBTs 18 to 20 are switched from on to off, the induced voltages of the motor 28 cause the IGBTs 18 to 20 to change.
Current that was flowing to the upper arm diode 2 when off
It returns to 1 to 23 and flows into the smoothing capacitor 13. As a result, the DC voltage between the high potential power supply line 3 and the low potential power supply line 4 is boosted. This boosting effect becomes greater as the rotation speed of the motor 28 is higher and the induced voltage is higher. Further, the higher the rotation speed of the motor 28, the larger the current flowing through the IGBTs 18 to 20 during the charge pump operation.

According to this embodiment, the drive signal has a PWM waveform, and the higher the rotation speed of the motor 28, the more the PWM
Since the ON pulse width of the drive signal is narrowed, the boosting action can be suppressed and the current flowing through the IGBTs 18 to 20 can be limited. Further, as the ON pulse width of the PWM drive signal becomes narrower, the PWM drive signal length becomes longer, so that the charging voltage of the capacitors 39 to 41 does not decrease.

(Seventh Embodiment) Next, a seventh embodiment of the present invention (corresponding to claim 16) will be described with reference to FIG. The inverter device in this embodiment has substantially the same configuration as the inverter device 51 shown in FIG. Figure 1
4 is a flowchart showing the drive start processing of the motor 28 executed by the control circuit, which is different from the flowchart shown in FIG. 4 in that steps S41 and S91 are added.

In step S4, the control circuit turns off the lower arm IGBTs 18 to 20 to complete the charging operation of the capacitors 39 to 41. After that, the control circuit does not immediately shift to the rotation speed detection in step S2 but waits for a predetermined time in step S41 (delay operation). The same applies to steps S9 and S91.

Even if the IGBTs 18 to 20 are switched from on to off to complete the charge pump operation, the above-described boosting action occurs. Until the boosting action disappears, the current flows back to the diodes 21 to 26, and the terminal voltages VU, V
V and VW have the same potential as the high potential power supply line 3 or the low potential power supply line 4, respectively. In this state, the induced voltage detection circuit 4
5 does not output correct phase signals SA and SB.

According to the present embodiment, the control means waits for a predetermined time after the end of the charge pump operation, that is, until the transient phenomenon such as the step-up action disappears, and then shifts to the detection operation. Therefore, the control means is based on the induced voltage of the motor 28. Accurate phase signal S
A and SB can be obtained. As a result, accurate rotation speed and phase can be obtained, and there will be no failure in starting driving or loss of synchronization after starting driving.

(Eighth Embodiment) Next, an eighth embodiment (corresponding to claim 8) of the present invention will be described with reference to FIG. 15 showing an electrical configuration of an inverter device. In the inverter device 80 according to the present embodiment, the control circuit 81 includes a phase correction unit 82 (corresponding to a phase correction unit) and a rotation speed correction unit 8.
3 (corresponding to the rotation speed correction means).

The control circuit 81 executes the drive start processing according to the flowchart shown in FIG. In this case, there is a slight time delay from the execution of step S5 for obtaining the rotation speed to the start of energization of the stator windings 28u, 28v, 28w of the motor 28. Further, there is a smaller time delay (for example, several msec) from the execution of step S10 for obtaining the phase to the start of energization.
Therefore, when the rotation speed is high, this time delay may cause an error in the rotation speed or phase at the start of driving.

Therefore, the phase corrector 82 operates in step S1.
When the phase is obtained at 0, the phase correction value is obtained by multiplying the rotation speed and the delay time assumed in advance,
The phase correction value is added to the detected phase. Accordingly, the phase correction unit 82 can more accurately obtain the phase at the start of driving. Further, the phase correction unit 82 may be provided with a table of phase correction values in advance, and the phase correction values may be read from the table.

On the other hand, the rotation speed correction unit 83 determines in step S
The detection of the rotation speed by 2 to S4 is executed twice, and the change rate of the rotation speed is obtained from the rotation speed detected at the first time and the rotation speed detected at the second time. Then, the rotation speed correction unit 83
In step S5, a rotation speed correction value is obtained based on the rate of change and a delay time estimated in advance, and the rotation speed correction value is added to the detected rotation speed. This allows
The rotation speed correction unit 83 can more accurately obtain the rotation speed at the start of driving. Further, the rotation speed correction unit 83
May include a rotation speed correction value tabulated in advance, and the rotation speed correction value may be read from the table.

(Other Embodiments) The present invention is not limited to the embodiments described above and shown in the drawings, but can be expanded or modified as follows. When an error is allowed in the phase and the rotation speed at the start of driving, the phase detection end determination unit and the rotation speed detection end determination unit determine the phase signal S output from the induced voltage detection circuit 45.
Instead of detecting the level change (edge) of A and SB, the level itself may be detected to obtain the phase and the rotation speed.

Further, the induced voltage detecting circuit 45 compares the terminal voltages Vu and Vv to obtain the phase signal SA, and the terminal voltage V
Although the phase signal SB is obtained by comparing v and Vw, the phase signal SC may be obtained by further comparing the terminal voltages Vu and Vw. As a result, an edge is generated every 60 °, so that the time required to start driving can be shortened.

In the first embodiment and the fourth to eighth embodiments, the rotational speed may be detected after the phase is detected. Further, the phase detection and the rotation speed detection may be executed in parallel.

In the second embodiment, the phase detection end judging section 5
A limiter may be provided at 5. Further, in the third embodiment, a limiter may be provided in the rotation speed detection end determination unit 56. Furthermore, the control circuit 61 is provided with a control circuit phase correction unit in the second embodiment, and the control circuit 6 is used in the third embodiment.
5 may be provided with a rotation speed correction unit.

In each of the above embodiments, the permanent magnet electric motor was driven as the motor 28, but other electric motors can be applied. For example, in the induction motor, a slight induced voltage is generated in the stator winding due to the residual magnetic field, so that the rotational speed and the phase can be detected based on the induced voltage.

The switching element is not limited to the IGBT,
For example, it may be an FET or a bipolar transistor. Further, the inverter circuit may have a single-phase bridge structure or a multi-phase bridge structure.

The lower arm drive circuits 32 to 34 commonly have one lower arm drive power supply 35, but may have separate lower arm drive power supplies. Also, the capacitors 39-
When charging 41, the IGBTs 18 to 20 of the lower arm are turned on / off all at once, but may be turned on / off at timings independent of each phase.

[0114]

As described above, the inverter device of the present invention is provided with the upper arm drive power source for charging the charge pump capacitor from the lower arm drive power source by the charge pump operation, and at least periodically before driving the electric motor. Perform the phase detection operation of the rotor, and start driving the motor in response to the completion of phase detection,
The configuration is such that the charge pump capacitor charging operation is performed periodically and during the non-operation of the phase detection operation until it is determined that the phase detection is completed. However, the detected phase can be used to synchronize with the electric motor.

Further, since the phase detecting operation and the charge pump capacitor charging operation are periodically executed and are not simultaneous operations, accurate phase detection can be performed.
Moreover, since the time from the detection of the phase and the charging of the charge pump capacitor to the start of driving the motor is shortened, the phase error is small and the charging voltage of the charge pump capacitor is high at the start of driving. The drive of the electric motor can be started more reliably.

Even when the rotational speed is detected instead of the above phase detection, the rotational speed error becomes small at the start of driving, and the charge pump capacitor is fully charged. It is possible to reliably start the drive in the state of taking.

Further, the phase detecting operation and the rotational speed detecting operation are periodically performed, and the charging operation of the charge pump capacitor is periodically performed during the non-execution of the phase and rotational speed detecting operation. As a result, the phase error and the rotational speed error at the start of driving are reduced, and it becomes easier to synchronize with the electric motor.

[Brief description of drawings]

FIG. 1 is an electrical configuration diagram of an inverter device showing a first embodiment of the present invention.

FIG. 2 is an electrical configuration diagram of an induced voltage detection circuit.

FIG. 3 is a waveform diagram of induced voltage and phase signals SA and SB.

FIG. 4 is a flowchart showing a rotational speed and phase detection operation.

FIG. 5 is a view corresponding to FIG. 1 showing a second embodiment of the present invention.

FIG. 6 is a view corresponding to FIG.

FIG. 7 is a view corresponding to FIG. 1 showing a third embodiment of the present invention.

FIG. 8 is a flowchart showing a phase and rotational speed detection operation.

FIG. 9 is a view corresponding to FIG. 1 showing a fourth embodiment of the present invention.

FIG. 10 is a view corresponding to FIG. 1 showing a fifth embodiment of the present invention.

11A is a diagram showing a relationship between a charging operation time interval and a charging operation time, and FIG. 11B is a diagram showing a relationship between a charging voltage and a charging operation time.

FIG. 12 is a view corresponding to FIG. 1 showing a sixth embodiment of the present invention.

[Fig. 13] PWM of a motor rotation speed and a PWM drive signal
Diagram showing the relationship between frequency, duty ratio, and time width

FIG. 14 is a view corresponding to FIG. 4 showing a seventh embodiment of the present invention.

FIG. 15 is a view corresponding to FIG. 1 showing an eighth embodiment of the present invention.

FIG. 16 is a view corresponding to FIG. 1 showing a conventional technique.

[Explanation of symbols]

3 is a high potential power supply line (DC power supply line), 4 is a low potential power supply line (DC power supply line), 14 is an inverter circuit, 15 to 17 are IGBTs (upper arm switching elements), 18 to 20 are IGBTs (lower arm switching). Elements), 29 to 31 are upper arm drive circuits, 32 to 34 are lower arm drive circuits, 3
5 is a lower arm drive power source, 36 to 38 is an upper arm drive power source, 39 to 41 are capacitors (charge pump capacitors), 51, 60, 64, 68, 72, 76, 80 are inverter devices, 52, 61, 65, 69, 73, 77,
Reference numeral 81 is a control circuit (control means), 53 is a phase detection section (phase detection means), 54 is a rotation speed detection section (rotation speed detection means), and 55, 70, 74 and 78 are phase detection end determination sections (phase detection end). (Determination means, charge control means), 56, 7
Reference numerals 1, 75 and 79 denote rotation speed detection end determination units (rotation speed detection end determination means and charging control means), and 57, 63 and 67 are drive start control portions (drive start control means).

Front Page Continuation (72) Inventor Takayuki Ishii 2121 No. 21 Sanyo, Asahi-cho, Mie-gun, Mie Prefecture Mie Plant, Toshiba Corporation (56) Reference JP-A-5-137349 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H02M 7/48

Claims (16)

(57) [Claims] 1. An inverter circuit for driving a motor, which comprises an upper arm switching element and a lower arm switching element connected in series between DC power supply lines, an upper arm drive circuit for driving the upper arm switching element, A lower arm drive circuit that drives the lower arm switching element, a lower arm drive power supply that supplies a drive DC voltage to the lower arm drive circuit, and a charge pump capacitor that supplies a drive DC voltage to the upper arm drive circuit. An upper arm drive power supply that charges the charge pump capacitor from the lower arm drive power supply when the lower arm switching element is in an ON state, and drives the upper arm drive circuit and the lower arm drive circuit. And a control means for outputting a signal, wherein the control means includes at least the power source. Phase detection means for detecting the phase of the rotor of the electric motor before driving the machine, and the phase detection means periodically performs detection operation until it is determined that the phase detection by the phase detection means is completed. A phase detection end determination means, a drive start control means for starting the drive of the electric motor in response to the phase detection end determination means determining that the phase detection is completed, and the phase detection end determination means Charge control for generating the drive signal such that the charge pump capacitor charging operation is performed periodically and while the phase detecting operation is not being performed until the detection is determined to be completed. An inverter device comprising: a means. 2. An inverter circuit for driving a motor comprising an upper arm switching element and a lower arm switching element connected in series between DC power supply lines, an upper arm driving circuit for driving the upper arm switching element, A lower arm drive circuit that drives the lower arm switching element, a lower arm drive power supply that supplies a drive DC voltage to the lower arm drive circuit, and a charge pump capacitor that supplies a drive DC voltage to the upper arm drive circuit. An upper arm drive power supply that charges the charge pump capacitor from the lower arm drive power supply when the lower arm switching element is in an ON state, and drives the upper arm drive circuit and the lower arm drive circuit. And a control means for outputting a signal, wherein the control means includes at least the power source. Rotational speed detection means for detecting the rotational speed of the electric motor before driving the machine, and a detection operation periodically performed by the rotational speed detection means until it is determined that the detection of the rotational speed by the rotational speed detection means is completed. Rotation speed detection end determination means for performing the rotation speed detection, drive start control means for starting the driving of the electric motor in response to the rotation speed detection end determination means determining that the rotation speed detection is completed, and the rotation speed detection Until the end determination means determines that the rotation speed has been detected, the charging operation of the charge pump capacitor is performed periodically and during the non-execution of the rotation speed detection operation by the rotation speed detection means. And an electric charge control means for generating the drive signal. 3. An inverter circuit for driving a motor, which comprises an upper arm switching element and a lower arm switching element connected in series between DC power supply lines, an upper arm drive circuit for driving the upper arm switching element, and A lower arm drive circuit that drives the lower arm switching element, a lower arm drive power supply that supplies a drive DC voltage to the lower arm drive circuit, and a charge pump capacitor that supplies a drive DC voltage to the upper arm drive circuit. An upper arm drive power supply that charges the charge pump capacitor from the lower arm drive power supply when the lower arm switching element is in an ON state, and drives the upper arm drive circuit and the lower arm drive circuit. And a control means for outputting a signal, wherein the control means includes at least the power source. Phase detection means for detecting the phase of the rotor of the electric motor before driving the motor, rotation speed detection means for detecting the rotation speed of the electric motor at least before driving the electric motor, and phase detection by the phase detection means Until it is determined that it has ended, the phase detection end determination unit that causes the phase detection unit to periodically perform a detection operation, and until it is determined that the detection of the rotation speed by the rotation speed detection unit is completed, A rotation speed detection end determination unit that causes the rotation speed detection unit to periodically perform a detection operation, and the phase detection end determination unit determines that the phase detection is completed and the rotation speed detection end determination unit detects the rotation speed. That the detection of the phase is completed by the drive start control means for starting the drive of the electric motor in response to the determination that Is determined and the rotation speed detection end determination means determines that the rotation speed has been detected, the charging operation of the charge pump capacitor is cyclic and the phase detection operation by the phase detection means and the rotation are performed. An inverter device comprising: a charge control unit that generates the drive signal so as to be performed while the rotational speed detection operation of the speed detection unit is not being executed. 4. The inverter device according to claim 1, wherein the control means comprises a phase correction means for correcting the phase of the rotor of the electric motor detected by the phase detection means. 5. The phase detection end determination means determines that the phase detection is completed when the number of executions of the charging operation of the charge pump capacitor reaches a predetermined number before the completion of the phase detection by the phase detection means. The inverter device according to any one of claims 1, 3, and 4, wherein. 6. The inverter device according to claim 2, wherein the control means includes a rotation speed correction means for correcting the rotation speed of the electric motor detected by the rotation speed detection means. 7. The rotation speed detection end determining means ends the detection of the rotation speed when the number of executions of the charging operation of the charge pump capacitor reaches a predetermined number before the rotation speed detecting means ends the detection of the rotation speed. The inverter device according to any one of claims 2, 3 and 6, wherein the inverter device is determined to be a device. 8. The phase correction means for correcting the phase of the rotor of the electric motor detected by the phase detection means,
4. The inverter device according to claim 3, further comprising a rotation speed correction unit that corrects the rotation speed of the electric motor detected by the rotation speed detection unit. 9. The phase detection end determination means determines that the phase detection has been completed when the number of executions of the charge pump capacitor charging operation reaches a predetermined number before the phase detection means completes the phase detection. The rotation speed detection end determination means determines that the rotation speed detection is completed when the number of executions of the charge pump capacitor charging operation reaches a predetermined number before the rotation speed detection means completes the detection of the rotation speed. The inverter device according to claim 3, wherein the inverter device comprises: 10. The charging control means determines the charging operation time of the charge pump capacitor based on a time interval for performing the charging operation of the charge pump capacitor. Inverter device described. 11. A charging voltage detecting means for detecting a charging voltage of the charge pump capacitor, wherein the charging control means determines a charging operation time of the charge pump capacitor based on the charging voltage detected by the charging voltage detecting means. The inverter device according to claim 1, wherein the inverter device is determined. 12. The charging control means generates a drive signal by PWM control, according to any one of claims 1 to 11.
The inverter device according to any one of 1. 13. The inverter device according to claim 12, wherein the charging control means determines the duty ratio of the drive signal based on the rotation speed of the electric motor. 14. The inverter device according to claim 12, wherein the charge control means determines the PWM frequency of the drive signal based on the rotation speed of the electric motor. 15. The inverter device according to claim 12, wherein the charging control means determines the time width of the drive signal based on the rotation speed of the electric motor. 16. The inverter device according to claim 1, wherein the charge control means suspends the detection operation for a predetermined period after the charge pump capacitor is charged.