JP2021145393A - Temperature estimation device of rotary electric machine and temperature estimation method of rotary electric machine - Google Patents

Abstract

To provide a temperature estimation device of a rotary electric machine and a temperature estimation method of the rotary electric machine which can accurately estimate the temperature of a part forming the rotary electric machine when the rotary electric machine is made small in diameter and rotated at high speed.SOLUTION: A temperature estimation device 10 of a rotary electric machine estimates the temperature of a component of the rotary electric machine ( a motor for driving 14 or a power generation motor 16) having a rotor 34 on a core part of which a magnet is arranged and a stator 30 on a slot part 30 of which a coil 28 is arranged. The temperature estimation device 10 of the rotary electric machine comprises a temperature sensor 61 provided inside a housing 41 for housing the rotary electric machine, a heat quantity calculation part 64 for calculating the heat quantity of the component, an eddy loss estimation part 68 for estimating the eddy loss of the coil 28 based on the rotation number, torque and applied voltage of the rotary electric machine, and a component temperature calculation part 70 for calculating the temperature of the component from the heat quantity of the component and the eddy loss of the coil 28.SELECTED DRAWING: Figure 1

Description

The present invention relates to a temperature estimation device for a rotary electric machine and a temperature estimation method for a rotary electric machine.

Hybrid vehicles and electric vehicles are equipped with a rotary electric machine (motor / generator) equipped with a rotor in which a magnet is arranged in a core portion and a stator in which a coil is arranged in a slot portion for driving or power generation. There is. In such a rotary electric machine, components such as a coil and a magnet generate heat, so that temperature is detected by a temperature sensor in order to prevent the coil from burning due to overheating and the magnet from deteriorating.

For example, Patent Document 1 discloses a technique for detecting the temperature of a coil by providing a temperature sensor at the coil end portion of the stator.

Japanese Unexamined Patent Publication No. 2008-136324

When the diameter of the rotary electric machine is reduced and the rotation speed is increased, when the width of the tip of the tooth is reduced, magnetic saturation occurs at the tip of the tooth, and the magnetic flux leakage to the coil tends to increase. Therefore, the loss (vortex loss) due to the eddy current increases in the coil.

The leakage magnetic field that causes an eddy current in the coil is locally different, and the temperature rise due to the eddy loss of the coil differs depending on the location. Therefore, if only a temperature sensor is provided at the coil end or the like as in the conventional case, the difference between the temperature detected value by the temperature sensor and the actual coil temperature changes depending on the operating point of the rotary electric machine. There is a problem that it is difficult to detect the temperature accurately.

An object of the present invention is to provide a temperature estimation device for a rotary electric machine and a temperature estimation method for the rotary electric machine, which can accurately estimate the temperature of parts constituting the rotary electric machine when the diameter of the rotary electric machine is reduced and the rotation speed is increased. do.

One aspect of the present invention is a temperature estimation device for a rotary electric machine that estimates the temperature of a component of a rotary electric machine having a rotor in which a magnet is arranged in a core portion and a stator in which a coil is arranged in a slot portion. The coil is based on at least a temperature sensor provided inside a housing for accommodating the rotary electric machine, a calorific value calculation unit for calculating the calorific value of the component, and the rotation speed, torque, and applied voltage of the rotary electric machine. Temperature estimation of a rotary electric machine including a vortex loss estimation unit for estimating the vortex loss of the It is in the device.

Another aspect of the present invention is a method for estimating the temperature of a rotary electric machine, which estimates the temperature of a component of a rotary electric machine having a rotor in which a magnet is arranged in a core portion and a stator in which a coil is arranged in a slot portion. Then, the step of obtaining the calorific value due to the iron loss of the stator, the vortex loss of the magnet, the iron loss of the rotor, and the copper loss of the coil, the torque of the rotating electric machine, the number of rotations, and the applied voltage. , The step of obtaining the vortex loss of the coil by referring to the map showing the relationship between the torque, the number of rotations, and the applied voltage of the rotary electric machine and the vortex loss of the coil, and the iron loss of the stator. A method for estimating the temperature of a rotary electric machine, which comprises a step of estimating the temperature of the component based on the vortex loss of the magnet, the iron loss of the rotor, and the copper loss of the coil and the vortex loss of the coil. be.

According to the temperature estimation device of the rotary electric machine and the temperature estimation method of the rotary electric machine from the above viewpoint, the rotary electric machine is configured when the diameter of the rotary electric machine is reduced and the rotation speed is increased by considering the influence of the vortex loss of the coil. The temperature of the coil, which is a component, can be estimated accurately.

It is a block diagram of the temperature estimation device of the rotary electric machine which concerns on embodiment of this invention. It is sectional drawing which shows the structure of a part of the drive motor in the rotary electric machine which concerns on embodiment of this invention. It is a figure seen from the axial direction which shows typically the structure of the drive motor in the rotary electric machine which concerns on embodiment of this invention. It is an enlarged view which saw a part of the stator core of the drive motor in the rotary electric machine which concerns on embodiment of this invention from the axial direction. It is sectional drawing which shows the structure around the coil end part of the drive motor in the rotary electric machine which concerns on embodiment of this invention. It is a perspective view which shows the structure of the coil end part of the stator core and the split conductor (segment coil) in the drive motor of the rotary electric machine which concerns on embodiment of this invention. It is a figure which shows typically the thermal model in the temperature estimation apparatus of the rotary electric machine which concerns on embodiment of this invention. It is explanatory drawing which shows the map which shows the relationship between the vortex loss of a coil, the torque, the rotation speed and the applied voltage in the temperature estimation apparatus of the rotary electric machine which concerns on embodiment of this invention. It is a flowchart which shows the operation of the temperature estimation apparatus of the rotary electric machine which concerns on embodiment of this invention. It is a flowchart which shows the calculation process of the calorific value of the component (coil) shown in FIG. It is a flowchart which shows the heat removal amount calculation process shown in FIG.

Hereinafter, preferred embodiments of the present invention will be mentioned and described in detail with reference to the accompanying drawings.

(First Embodiment)
The temperature estimation device 10 of the rotary electric machine according to the present embodiment is mounted on a vehicle 12 such as a hybrid vehicle or an electric vehicle. As shown in FIG. 1, the vehicle 12 includes a drive motor 14, a power generation motor 16, a transmission 18, a refrigerant circulation unit 20, a power conversion unit 22, a battery 24, and a control device 26.

Each of the drive motor 14 and the power generation motor 16 is composed of, for example, a three-phase AC brushless DC motor or the like. The drive motor 14 and the power generation motor 16 each include a rotating shaft connected to the transmission 18. The rotating shaft of the power generation motor 16 is connected to a mechanical pump of the refrigerant circulation unit 20, which will be described later.

As shown in FIGS. 2 and 3, the drive motor 14 includes a stator 30 having a coil 28 and a rotor 34 having a magnet 32. The drive motor 14 is an inner rotor type, and has a rotor 34 inside a cylindrical stator 30.

The coil 28 is an SC (segment conductor) winding. As shown in FIGS. 4 to 6, the coil 28 is mounted in a slot portion 30c formed between adjacent teeth 30b of the stator core 30a. The coil 28 is connected to a power conversion unit 22, which will be described later.

The outer shape of the stator core 30a is formed in a cylindrical shape. As shown in FIG. 4, the stator core 30a includes a plurality of teeth 30b on the inner peripheral portion in the radial direction. Each of the plurality of teeth 30b projects toward the inner peripheral side at a predetermined interval in the circumferential direction at the inner peripheral portion of the stator core 30a. The slot portion 30c is formed between the teeth 30b adjacent to each other in the circumferential direction. Each slot portion 30c is formed so as to extend radially from the inner peripheral side in the radial direction of the stator core 30a toward the outer peripheral side. Further, the slot portion 30c extends so as to penetrate the inner peripheral portion of the stator core 30a in the direction of the rotation axis.

The coil 28 is a three-phase coil composed of a U phase, a V phase, and a W phase. As shown in FIG. 5, the coil 28 includes a plurality of segment coils 28a. Each segment coil 28a includes a plurality of conductors having a rectangular cross section. The plurality of conductors are arranged in a row so that the surfaces of the copper wires face each other to form one bundle. The outer shape of each segment coil 28a is formed in a U shape so as to fill each slot portion 30c without gaps according to the shape of each slot portion 30c.

Both ends of each segment coil 28a are inserted into two slot portions 30c spaced apart from each other in the circumferential direction from the axial direction of the stator core 30a. The ends of the segment coils 28a are joined to each other by TIG welding or the like among a plurality of ends protruding from the inside of each slot portion 30c to the outside. The ends of the plurality of segment coils 28a inserted into the plurality of slot portions 30c are sequentially arranged in the circumferential direction of U-phase, U-phase, V-phase, V-phase, W-phase, W-phase, U-phase, U-phase, and so on. They are arranged in order.

The magnet 32 is, for example, a permanent magnet. As shown in FIG. 2, the magnet 32 is held inside the rotor yoke 34a so as not to come into direct contact with the pair of end face plates 34b that sandwich the rotor yoke 34a from both sides in the axial direction of the rotating shaft 34c.

The power generation motor 16 is configured in the same manner as the drive motor 14.

The transmission 18 is, for example, an AT (automatic transmission) or the like, and includes a gear, a clutch, and the like. As shown in FIG. 1, the transmission 18 is connected to each of the drive motor 14 and the power generation motor 16 and the drive wheels 36. The transmission 18 controls power transmission between each of the drive motor 14 and the power generation motor 16 and the drive wheels 36 in response to a control signal output from the control device 26 described later. The transmission 18 is housed inside the housing 41 (transmission case) together with the drive motor 14 and the power generation motor 16. That is, in addition to the rotary electric machine such as the drive motor 14 or the power generation motor 16, transmission parts such as gears and clutches are also housed inside the housing 41. A refrigerant storage unit 39 (oil pan) is provided at the bottom of the housing 41. The refrigerant that has passed through the drive motor 14 and the power generation motor 16 is stored in the refrigerant storage unit 39. The refrigerant storage unit 39 is provided with a temperature sensor 61. The temperature sensor 61 detects the temperature of the refrigerant collected in the refrigerant storage unit 39.

The refrigerant circulation unit 20 includes a refrigerant flow path 20a through which the refrigerant circulates and a cooler 20b for cooling the refrigerant. The refrigerant circulation unit 20 uses, for example, hydraulic oil for lubrication, power transmission, and the like as a refrigerant in the transmission 18 of an AT (automatic transmission).

The refrigerant flow path 20a is connected to the flow path of the hydraulic oil inside the transmission 18, and the inside of each of the drive motor 14 and the power generation motor 16. The refrigerant flow path 20a includes a discharge port 20c that discharges refrigerant to each of the drive motor 14 and the power generation motor 16, and a suction port 20d that sucks the refrigerant that has flowed inside each of the drive motor 14 and the power generation motor 16. (See FIG. 7). The discharge port 20c of the refrigerant flow path 20a is arranged above each of the drive motor 14 and the power generation motor 16 in the vertical direction. Further, the suction port 20d is provided in the refrigerant storage portion 39 inside the housing 41 accommodating the drive motor 14, the power generation motor 16, and the transmission 18.

The cooler 20b includes a mechanical pump provided in the refrigerant flow path 20a and connected to the rotating shaft of the power generation motor 16. The mechanical pump generates a suction force by driving the power generation motor 16, sucks the refrigerant from the suction port 20d of the refrigerant flow path 20a, and causes the refrigerant in the refrigerant flow path 20a to flow toward the discharge port 20c. The cooler 20b cools the refrigerant flowing in the refrigerant flow path 20a.

The refrigerant circulation unit 20 is provided with respect to the drive motor 14 from the discharge port 20c of the refrigerant flow path 20a to the coil end portion 28b (out of the axial direction from the slot portion 30c of the stator core 30a) as the mechanical pump of the cooler 20b operates. The refrigerant is discharged toward the end of the coil 28 that protrudes toward the direction). As shown in FIGS. 5 and 6, the refrigerant flows vertically downward on the surfaces of the segment coil 28a and the stator core 30a of the coil end portion 28b by the action of gravity. The arrows in FIGS. 5 and 6 schematically show the flow state of the refrigerant. The refrigerant passes through the gap between the coil 28 and the rotor 34 and flows downward in the vertical direction so as to come into contact with the end face plate 34b.

The refrigerant that comes into contact with the surface of the end face plate 34b flows on the surface of the end face plate 34b toward the outside of the end face plate 34b by the action of centrifugal force and gravity due to the rotation of the rotor 34. The refrigerant flows to the refrigerant storage unit 39 by the action of gravity outside the end face plate 34b.

The refrigerant circulation unit 20 sucks the refrigerant stored in the refrigerant storage unit 39 from the suction port 20d into the refrigerant flow path 20a by suction of the mechanical pump, and cools the refrigerant by the cooler 20b. As a result, as shown in FIG. 7, the refrigerant circulation unit 20 cools the coil 28 and the magnet 32 with the refrigerant. More specifically, the refrigerant circulation unit 20 directly cools the end face plate 34b with the refrigerant, and indirectly and sequentially cools the rotor 34 and the magnet 32 with the refrigerant via the end face plate 34b. ..

As shown in FIG. 1, the power conversion unit 22 includes a booster 40 that boosts the output voltage of the battery 24, a first power drive unit 42 (PDU1) that controls energization of the drive motor 14, and a power generation motor 16. It is equipped with a second power drive unit 44 (PDU2) that controls energization.

The booster 40 includes, for example, a DC-DC converter or the like. The booster 40 is connected between the battery 24 and the first power drive unit 42 and the second power drive unit 44. The booster 40 generates the voltage applied to the first power drive unit 42 and the second power drive unit 44 by boosting the output voltage of the battery 24 in response to the control signal output from the control device 26 described later. That is, the booster 40 outputs the applied voltage generated by boosting the output voltage of the battery 24 to the first power drive unit 42 and the second power drive unit 44.

The first power drive unit 42 and the second power drive unit 44 include, for example, an inverter device or the like. The first power drive unit 42 and the second power drive unit 44 include, for example, a bridge circuit formed by bridging using a plurality of switching elements (for example, MOSFETs and the like) and a smoothing capacitor as an inverter device. The first power drive unit 42 and the second power drive unit 44 convert the DC output power of the booster 40 into three-phase AC power according to the control signal output from the control device 26 described later. A three-phase alternating current is applied to each of the three-phase coils 28 so that the first power drive unit 42 sequentially transfers current to the drive motor 14 and the second power drive unit 44 to the power generation motor 16. Energize.

The control device 26 is composed of a CPU (Central Processing Unit), various storage media such as a RAM (Random Access Memory), and an electronic circuit such as a timer. The control device 26 outputs a control signal for controlling the transmission 18 and the power conversion unit 22. The control device 26 is connected to a voltage sensor 46, a first current sensor 48, a second current sensor 50, a first rotation speed sensor 52, a second rotation speed sensor 54, a torque sensor 56, and temperature sensors 58, 59, 60, 61. Has been done.

The voltage sensor 46 detects the applied voltage applied from the booster 40 to each of the first power drive unit 42 and the second power drive unit 44. The first current sensor 48 detects an alternating current (phase current) flowing between the first power drive unit 42 and each coil 28 of the drive motor 14. The second current sensor 50 detects an alternating current (phase current) flowing between the second power drive unit 44 and each coil 28 of the power generation motor 16. The first rotation speed sensor 52 detects the rotation speed of the drive motor 14 by sequentially detecting the rotation angle of the rotation shaft of the drive motor 14. The second rotation speed sensor 54 detects the rotation speed of the power generation motor 16 by sequentially detecting the rotation angle of the rotation shaft of the power generation motor 16. The torque sensor 56 detects the torque of the drive motor 14. The temperature sensor 58 detects the temperature of the outer peripheral portion of the coil 28. The temperature sensor 59 detects the temperature of the refrigerant discharged from the discharge port 20c. The temperature sensor 60 detects the temperature of the refrigerant after being discharged from the discharge port 20c of the refrigerant flow path 20a and exchanging heat with the coil end portion 28b.

As shown in FIG. 4, the temperature sensor 58 is provided adjacent to a part of the outer peripheral portion of the coil 28, and detects the temperature of the outer peripheral portion of the coil 28. When the drive motor 14 or the power generation motor 16 is rotated at high speed, the vortex loss of the coil 28 increases, and the amount of heat generated inside the coil 28 increases. Therefore, the temperature sensor 58 alone reduces the responsiveness when the output of the coil 28 fluctuates.

As shown in FIG. 5, the temperature sensor 60 is arranged below the coil end portion 28b. The temperature sensor 60 is fixed to a bracket 62b connected to the side cover 62 by a screw 62a. The side covers 62 are arranged so as to sandwich the housing 38 from both sides in the axial direction. After exchanging heat with the coil end portion 28b, the temperature sensor 60 detects the temperature of the refrigerant on the way to the bottom portion 38a below the vertical direction of the housing 38.

The temperature sensor 61 is provided in the refrigerant storage unit 39, and detects the temperature of the refrigerant collected in the refrigerant storage unit 39. In the present embodiment, the detected temperature of the temperature sensor 61 is used for estimating the temperature of the coil 28, as will be described later.

As shown in FIG. 1, the control device 26 includes a calorific value calculation unit 64, a heat removal amount calculation unit 66, a vortex loss estimation unit 68, a component temperature calculation unit 70, a motor control unit 72, and a storage unit 74. And have. Of these, the calorific value calculation unit 64 calculates the calorific value due to the loss of each of the drive motor 14 and the power generation motor 16. The calorific value calculation unit 64 is based on, for example, copper loss and eddy loss of the three-phase coil 28, iron loss of the stator core 30a, eddy current loss of the magnet 32, and iron loss of the rotor yoke 34a in the drive motor 14. Calculate the calorific value.

The calorific value calculation unit 64 sets the three-phase current of the drive motor 14 detected by the first current sensor 48 and the resistance value of the coil 28 (drive motor 14) stored in the storage unit 74 in advance. Based on this, the copper loss of the coil 28 of the drive motor 14 is calculated.

Further, the calorific value calculation unit 64 obtains the calorific value due to the iron loss of the stator core 30a, the vortex loss of the magnet 32, and the iron loss of the rotor yoke 34a with reference to the map stored in the storage unit 74. That is, the calorific value calculation unit 64 includes the applied voltage detected by the voltage sensor 46, the rotation speed of the drive motor 14 detected by the first rotation speed sensor 52, and the drive motor 14 detected by the torque sensor 56. Based on the torque of the above, the amount of heat generated by the iron loss of the stator core 30a, the copper loss of the coil 28, the eddy current loss of the magnet 32, and the iron loss of the rotor yoke 34a is calculated. The various data are data such as a map showing the interrelationship between the applied voltage, the rotation speed, and the torque and the eddy current loss of the magnet 32.

The vortex loss estimation unit 68 includes the applied voltage detected by the voltage sensor 46, the rotation speed of the drive motor 14 detected by the first rotation speed sensor 52, and the torque of the drive motor 14 detected by the torque sensor 56. And, based on, the estimated value of the vortex loss of the coil 28 is obtained. The vortex loss estimation unit 68 reads out the map stored in the storage unit 74 and estimates the vortex loss of the coil 28. For example, the map for estimating the vortex loss of the coil 28 is composed of the data as shown in FIG. The map of FIG. 8 is data showing the relationship between the rotation speed of the drive motor 14 and the torque and the estimated value of the vortex loss of the coil 28, with the torque on the horizontal axis and the vortex loss of the coil 28 on the vertical axis. be. A plurality of this map is prepared for each applied voltage.

The map showing the vortex loss of the coil 28 measures, for example, the current waveform flowing through the coil 28 in a state where a predetermined torque, rotation speed, and applied voltage are applied to the coil 28, and the vortex loss is generated using an electromagnetic field simulator. It is calculated by calculating the amount. The map shown in FIG. 8 can be obtained by measuring the current waveform flowing through the coil 28 while changing the torque, the rotation speed, and the applied voltage.

The calorific value calculation unit 64 includes the applied voltage detected by the voltage sensor 46, the rotation speed of the drive motor 14 detected by the first rotation speed sensor 52, and the torque of the drive motor 14 detected by the torque sensor 56. And get. Then, the calorific value calculation unit 64 obtains the value of the vortex loss corresponding to the applied voltage, the rotation speed, and the torque by referring to the map.

The heat removal amount calculation unit 66 includes the temperature of the refrigerant in the discharge port 20c detected by the temperature sensor 59, the refrigerant temperature in the refrigerant storage unit 39 detected by the temperature sensor 61, and the coil temperature and magnet temperature estimated in the previous process. The amount of heat dissipated from the rotor yoke 34a to the refrigerant (heat removal amount) is calculated based on the rotation speed of the power generation motor 16 detected by the second rotation speed sensor 54.

The heat removal amount calculation unit 66 detects the flow rate of the refrigerant circulated in the refrigerant circulation unit 20 based on the rotation speed of the power generation motor 16 detected by the second rotation speed sensor 54. Data such as a map showing the interrelationship between the rotation speed of the power generation motor 16 and the flow rate of the refrigerant is stored in advance in the storage unit 74. The heat removal amount calculation unit 66 calculates the heat amount (heat removal amount) radiated from the rotor yoke 34a to the refrigerant by referring to the data stored in the storage unit 74 in advance using the flow rate of the refrigerant. The storage unit 74 stores in advance data showing the interrelationship between the flow rate of the refrigerant and the amount of heat (heat removal amount) radiated from the rotor yoke 34a to the refrigerant.

The component temperature calculation unit 70 includes the heat generation amount due to the loss of each part of the drive motor 14 and the power generation motor 16 calculated by the calorific value calculation unit 64, the vortex loss of the coil 28 by the vortex loss estimation unit 68, and the vortex loss of the coil 28 by the vortex loss estimation unit 68. The temperature change of the coil 28 and the magnet 32 is calculated based on the amount of heat radiated to the refrigerant from the rotor yoke 34a calculated by the heat removal amount calculation unit 66 (heat removal amount). Since the change in the magnetic flux density received from the magnet 32 on the inner peripheral side of the coil 28 becomes large, the heat generated by the vortex loss on the inner peripheral side becomes large. The vortex loss estimation unit 68 can quickly estimate the increase in heat generation on the inner peripheral side of the coil 28.

The component temperature calculation unit 70 includes the heat generation amount due to the loss of each part of the drive motor 14 and the power generation motor 16 calculated by the heat generation amount calculation unit 64, and the refrigerant from the rotor yoke 34a calculated by the heat removal amount calculation unit 66. The temperature change of the component parts such as the coil 28 and the magnet 32 is calculated based on the amount of heat dissipated (heat removal amount). The component temperature calculation unit 70 calculates the temperature of the component estimated in the current process based on the temperature change of the component and the temperature of the component estimated in the previous process.

The motor control unit 72 outputs a control signal for controlling the transmission 18 and the power conversion unit 22 based on the temperatures of the coil 28 and the magnet 32 calculated by the vortex loss estimation unit 68 and the component temperature calculation unit 70. This controls the drive motor 14 and the power generation motor 16.

The temperature estimation device 10 of the rotary electric machine according to the present embodiment has the above configuration. Next, the operation of the temperature estimation device 10 of the rotary electric machine, that is, the temperature estimation method of the rotary electric machine will be described.

Hereinafter, a process in which the control device 26 calculates the temperature of the coil 28 of the drive motor 14 and controls the drive motor 14 will be described.

First, as shown in FIG. 9, the control device 26 acquires the torque of the drive motor 14 detected by the torque sensor 56 and the rotation speed of the drive motor 14 detected by the first rotation speed sensor 52. (Step S10).

Next, the control device 26 calculates the amount of heat generated by the components of the drive motor 14 (step S20).

Here, the calculation process of the calorific value of the coil 28 in step S20 described above will be described with reference to FIG.

First, the control device 26 multiplies the detected current (phase current) of the first current sensor 48 by the resistance value of the coil 28 of the drive motor 14 stored in the storage unit 74 to obtain copper loss in the coil 28. The amount of heat generated by the above is calculated (step S22).

Next, the control device 26 detects the applied voltage from the voltage sensor 46, detects the rotation speed of the drive motor 14 from the first rotation speed sensor 52, and acquires the torque of the drive motor 14 from the torque sensor 56. Then, the control device 26 refers to the map stored in the storage unit 74 based on the applied voltage, rotation speed, and torque of the drive motor 14, and the iron loss of the stator core 30a and the eddy current loss of the magnet 32. , And the iron loss of the rotor yoke 34a is calculated (step S24).

Next, the control device 26 calculates the amount of heat generated by the vortex loss of the coil 28 based on the torque, the rotation speed, and the applied voltage of the drive motor 14 with reference to the map (FIG. 8) (step S26).

After that, the control device 26 advances the processing to the return.

Next, as shown in FIG. 9, the control device 26 calculates the amount of heat removed (heat dissipation amount) from the rotor yoke 34a by the refrigerant (step S30). The heat removal amount calculation process is performed in the following steps.

As shown in FIG. 11, first, in the control device 26, the refrigerant temperature of the discharge port 20c detected by the temperature sensor 59 and the refrigerant temperature inside the housing 41 detected by the temperature sensor 61 (the temperature of the refrigerant storage unit 39). ) Is acquired (step S32). In step S32, the control device 26 may acquire the detected temperature of the temperature sensor 60 instead of the detected temperature of the temperature sensor 61.

Next, the control device 26 acquires the flow rate of the refrigerant based on the rotation speed of the power generation motor 16 detected by the second rotation speed sensor 54 (step S34).

Next, the control device 26 calculates the amount of heat (heat removal amount) radiated from the rotor yoke 34a to the refrigerant by referring to the data stored in the storage unit 74 in advance using the flow rate of the refrigerant (step S36). .. Then, the control device 26 advances the processing to the return.

Next, as shown in FIG. 9, the control device 26 is a component (coil 28) of the drive motor 14 based on the amount of heat generated by the loss of each part of the drive motor 14 and the amount of heat removed from the rotor yoke 34a by the refrigerant. And the temperature change of the magnet 32) is calculated. The control device 26 calculates the temperature of the component estimated in the current process based on the temperature change of the component and the temperature of the component estimated in the previous process (step S40).

Next, the control device 26 determines whether or not the calculated temperature of the component component is less than a predetermined output limit temperature (step S50). When this determination result is "YES", the control device 26 ends the process without limiting the output of the drive motor 14. On the other hand, when the determination result is "NO", the control device 26 advances the process to step S60.

Then, the control device 26 calculates the upper limit of the allowable torque of the drive motor 14 (step S60).

Next, the control device 26 outputs a control signal instructing the torque of the drive motor 14 to be equal to or less than the allowable torque upper limit to the power conversion unit 22 (step S70). Then, the control device 26 ends the process.

The control device 26 also estimates the temperature of the components of the power generation motor 16 by performing the processes described with reference to FIGS. 9 to 11. Then, the control device 26 controls the power generation motor 16 to prevent deterioration due to overheating based on the estimated temperature of the components of the power generation motor 16.

The temperature estimation device 10 and the temperature estimation method of the rotary electric machine of the present embodiment have the following effects.

This embodiment is a component of a rotary electric machine (drive motor 14 and power generation motor 16) having a rotor 34 in which a magnet 32 is arranged in a core portion and a stator 30 in which a coil 28 is arranged in a slot portion 30c. A temperature estimation device 10 of a rotary electric machine for estimating a temperature, a temperature sensor 61 provided inside a housing 41 accommodating the rotary electric machine, a calorific value calculation unit 64 for calculating a calorific value of a component, and a rotary electric machine. The vortex loss estimation unit 68 that estimates the vortex loss of the coil 28 based on the rotation speed, torque, and applied voltage of the component, and the component component that calculates the temperature of the component component from the calorific value of the component component and the vortex loss of the coil 28. A temperature calculation unit 70 is provided.

According to the above configuration, the heat generated by the vortex loss of the coil 28 can be included in the calculation of the temperature rise of the component. As a result, the temperatures of the coil 28 and the magnet 32 can be accurately estimated even when the eddy current loss of the coil 28 increases due to the smaller diameter and higher rotation of the rotary electric machine.

In the temperature estimation device 10 of the rotary electric machine, the component may be the coil 28. According to this configuration, the temperature of the coil 28 can be accurately estimated, and the coil 28 can be prevented from burning.

In the temperature estimation device 10 of the rotary electric machine, the component may be a magnet 32. According to this configuration, the temperature rise of the magnet 32 due to the increase in the vortex loss of the coil 28 can be accurately estimated. Therefore, deterioration of the magnet 32 due to a temperature rise can be prevented.

In the temperature estimation device 10 of the rotary electric machine, the vortex loss estimation unit 68 may have a storage unit 74 that stores a map showing the relationship between the rotation speed, torque, and voltage of the rotary electric machine and the vortex loss. According to this configuration, the vortex loss can be estimated by a simple process without performing complicated calculations based on the detection results of the rotation speed, torque and voltage.

In the temperature estimation device 10 of the rotary electric machine, the heat removal amount calculation unit 66 for obtaining the heat removal amount from the temperature of the refrigerant flowing through the rotary electric machine detected by the temperature sensor 61 is provided, and the component temperature calculation unit 70 includes the heat removal amount and the coil. The temperature of the component may be estimated based on the vortex loss of 28 and the calorific value of the component. This configuration further enhances the accuracy of component temperature estimation.

Further, in the temperature estimation method of the rotary electric machine of the present embodiment, the temperature of the component parts of the rotary electric machine having the rotor 34 in which the magnet 32 is arranged in the core portion and the stator 30 in which the coil 28 is arranged in the slot portion 30c is determined. Regarding the method of estimation. The temperature estimation method of the rotary electric machine includes a step of obtaining the amount of heat generated by the iron loss of the stator 30, the vortex loss of the magnet 32, the iron loss of the rotor 34, and the copper loss of the coil 28, the torque of the rotary electric machine, and the rotation. A step of obtaining the number and the applied voltage, a step of obtaining the vortex loss of the coil 28 by referring to a map showing the relationship between the torque, the number of rotations and the applied voltage of the rotary electric machine and the vortex loss of the coil 28, and a step of obtaining the vortex loss of the coil 28. It has a step of estimating the temperature of a component based on the iron loss of the stator 30, the vortex loss of the magnet 32, the iron loss of the rotor 34, and the copper loss of the coil 28 and the vortex loss of the coil 28.

According to the temperature estimation method of the rotary electric machine, the temperature of the coil 28 and the magnet 32 can be accurately estimated even when the diameter of the rotary electric machine is reduced and the rotation speed is increased.

Although the present invention has been described above with reference to preferred embodiments, it goes without saying that the present invention is not limited to the above-described embodiments and various modifications can be made without departing from the spirit of the present invention. stomach.

10 ... Temperature estimation device 28 ... Coil 30 ... Stator 30c ... Slot part 32 ... Magnet 34 ... Rotor 39 ... Refrigerant storage part 41 ... Housing 58, 59, 60, 61 ... Temperature sensor 64 ... Calorific value calculation unit 66 ... Heat removal amount calculation Unit 68 ... Vortex loss estimation unit 70 ... Component temperature calculation unit 74 ... Storage unit

Claims (6)

A temperature estimation device for a rotary electric machine that estimates the temperature of a component of a rotary electric machine having a rotor in which a magnet is arranged in a core portion and a stator in which a coil is arranged in a slot portion.
At least a temperature sensor provided inside the housing that houses the rotary electric machine, and
A calorific value calculation unit that calculates the calorific value of the component parts,
A vortex loss estimation unit that estimates the vortex loss of the coil based on the rotation speed, torque, and applied voltage of the rotary electric machine.
A temperature estimation device for a rotating electric machine including a component temperature calculation unit that calculates the temperature of the component based on the calorific value of the component and the vortex loss of the coil. The temperature estimation device for a rotary electric machine according to claim 1, wherein the component is a coil. The temperature estimation device for a rotary electric machine according to claim 1, wherein the component is a magnet. The temperature estimation device for a rotary electric machine according to any one of claims 1 to 3, wherein the vortex loss estimation unit provides a map showing the relationship between the rotation speed, torque and voltage of the rotary electric machine and the vortex loss. A temperature estimation device for a rotary electric machine having a stored storage unit. The temperature estimation device for a rotary electric machine according to any one of claims 1 to 4, further comprising a heat removal amount calculation unit for obtaining the heat removal amount from the temperature of the refrigerant flowing through the rotary electric machine detected by the temperature sensor. The component temperature calculation unit is a temperature estimation device for a rotating electric machine that estimates the temperature of the component based on the amount of heat removed, the vortex loss of the coil, and the amount of heat generated by the component. It is a temperature estimation method of a rotary electric machine that estimates the temperature of a component of a rotary electric machine having a rotor in which a magnet is arranged in a core portion and a stator in which a coil is arranged in a slot portion.
A step of obtaining the amount of heat generated by the iron loss of the stator, the vortex loss of the magnet, the iron loss of the rotor, and the copper loss of the coil.
The step of acquiring the torque, the rotation speed, and the applied voltage of the rotary electric machine,
A step of obtaining the vortex loss of the coil by referring to a map showing the relationship between the torque, the rotation speed, and the applied voltage of the rotary electric machine and the vortex loss of the coil.
A step of estimating the temperature of the component based on the iron loss of the stator, the vortex loss of the magnet, the iron loss of the rotor, and the copper loss and vortex loss of the coil.
A method for estimating the temperature of a rotating electric machine.

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