JP2018117462A - Temperature estimation system of rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately estimate the actual temperature of a stator coil in a rotary electric machine mounted on a vehicle.SOLUTION: A temperature estimation system 10 of a rotary electric machine comprises: a coil temperature sensor 40 for detecting the temperature of a stator coil 36 in a rotary electric machine 30 mounted on a vehicle; and an actual temperature estimation section 14 which, in a predetermined cycle, corrects a detected temperature Tct of the coil temperature sensor 40 to obtain the actual temperature estimated value of the stator coil 36. The actual temperature estimation section 14 calculates the amount of correction which varies according to: a speed v of the vehicle serving as an indicator for indicating the immersion state of the coil temperature sensor 40 in a refrigerant F; and the amount of a change in the detected temperature Tct of the coil temperature sensor 40. By correcting the detected temperature Tct of the coil temperature sensor 40 with the amount of correction, the actual temperature estimated value of the stator coil 36 is obtained.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a temperature estimation system that estimates the temperature of a stator coil of a rotating electrical machine mounted on a vehicle.

  Conventionally, a rotating electrical machine for driving wheels is mounted on an electric vehicle such as a hybrid vehicle or an electric vehicle. Since such a rotating electrical machine becomes hot during use, cooling is performed by supplying a refrigerant into a case that houses the rotating electrical machine. In addition, the temperature of the stator coil of the rotating electrical machine is detected by a temperature sensor, and when the detected temperature is high, the drive is controlled so as to limit the output of the rotating electrical machine, thereby suppressing the temperature rise of the rotating electrical machine. The components are protected.

  When the temperature of the stator coil is detected by a temperature sensor, the detected temperature may deviate from the actual temperature (actual temperature). Therefore, the detected temperature is conventionally corrected to estimate the actual temperature. Yes.

  In Patent Document 1, in a temperature estimation system for a rotating electrical machine having a temperature sensor for detecting the temperature of a stator coil, a temperature correction value related to the torque command value of the rotating electrical machine and the amount of change in temperature detected by the temperature sensor is used. Thus, it is disclosed that the detected temperature of the temperature sensor is corrected to estimate the actual temperature of the stator coil. In Patent Document 1, the temperature correction value is determined in consideration of a change in the manner of contact of the refrigerant supplied to the temperature sensor in the case housing the rotating electrical machine in accordance with the inclination state of the vehicle. .

JP 2015-33995 A

  By the way, the refrigerant (for example, cooling oil) supplied into the case cools the components of the rotating electrical machine (such as the stator coil) and then accumulates in the lower part of the case. The accumulated refrigerant is sucked out of the case, It will be supplied again into the case by the pump. As described above, since the refrigerant temporarily accumulates in the lower part of the case, when a temperature sensor (for example, a thermistor) is attached to the stator coil, the temperature sensor may be immersed in the refrigerant depending on the traveling state of the vehicle. (It may or may not be immersed in the refrigerant). Therefore, the detected temperature of the temperature sensor changes, and the deviation state between the detected temperature and the actual temperature changes. Since the correction amount for filling the gap between the detected temperature of the conventional temperature sensor and the actual temperature does not change depending on the immersion state (the presence or absence of immersion or the degree of immersion), there is room for improvement.

  Therefore, the present invention provides a detection temperature even when the difference between the detected temperature of the temperature sensor and the actual temperature changes depending on the immersion state of the temperature sensor of the stator coil in the refrigerant (the presence or absence of immersion or the degree of immersion). It is an object of the present invention to accurately correct the temperature so that an accurate actual temperature can be estimated.

  A temperature estimation system for a rotating electrical machine according to the present invention is a rotating electrical machine mounted on a vehicle, and is a rotating electrical machine housed in a case, and includes a stator coil that is cooled by supplying a coolant into the case. A temperature estimation system for a rotating electrical machine having a coil temperature sensor for detecting the temperature of the stator coil, and reducing a difference between a detected temperature of the coil temperature sensor and an actual temperature of the stator coil at a predetermined cycle An actual temperature estimator that calculates a correction amount for performing or eliminating, and corrects the detected temperature of the coil temperature sensor by the calculated correction amount to obtain an actual temperature estimated value of the stator coil, and the coil temperature The sensor is provided at a position where the sensor can be immersed in the refrigerant, and the actual temperature estimation unit serves as an index indicating the immersion state of the coil temperature sensor in the refrigerant. Serial and rotational speed of the speed or the rotating electrical machine of the vehicle, said calculating a correction amount changes according to a change amount of the detected temperature of the coil temperature sensor, and wherein the.

  In the temperature estimation system for a rotating electrical machine according to the present invention, it is preferable that the correction amount of the deviation varies according to a torque command value of the rotating electrical machine.

  In the temperature estimation system for a rotating electrical machine according to the present invention, it is preferable that the correction amount of the deviation is obtained by integrating correction amount fluctuations calculated in each period.

  In the temperature estimation system for a rotating electrical machine according to the present invention, the map is a map in which a temporary correction amount variation corresponding to the amount of change in temperature detected by the coil temperature sensor and the torque command value is set, and the difference in speed of the vehicle A plurality of maps corresponding to the above are stored in advance, a temporary correction amount variation corresponding to the current change amount and the torque command value is read from each of the plurality of maps, and the read temporary correction is read out It is also preferable that the correction amount fluctuation corresponding to the current vehicle speed is calculated using a relationship between each of the quantity fluctuations and the vehicle speed of the map from which they are read.

  The temperature estimation system for a rotating electrical machine according to the present invention is a map in which temporary correction amount fluctuations corresponding to the amount of change in temperature detected by the coil temperature sensor and the torque command value are set, and the number of rotations of the rotating electrical machine A plurality of maps corresponding to the differences are stored in advance, and a temporary correction amount variation corresponding to the current change amount and the torque command value is read from each of the plurality of maps, and the read temporary The correction amount fluctuation corresponding to the current rotation speed of the rotating electrical machine is calculated using a relationship between each of the correction amount fluctuations of the rotation speed and the rotation speed of the rotating electrical machine of the map from which they are read. Is also suitable.

  According to the present invention, the vehicle speed (vehicle speed) or the rotational speed of the rotating electrical machine is used as an index representing the immersion state (existence of immersion or degree of immersion) of the temperature sensor (coil temperature sensor) of the stator coil in the refrigerant. Since the temperature sensor detection temperature is corrected in consideration of the deviation state between the temperature sensor detection temperature and the stator coil actual temperature, which varies depending on the state, the actual stator coil temperature can be estimated accurately.

It is a figure which shows an example of a structure of the temperature estimation system of the rotary electric machine in embodiment of this invention. It is a figure which shows a mode that the coil temperature sensor was immersed in the refrigerant | coolant. It is a flowchart which shows an example of the flow of a calculation process of the actual temperature estimated value of the stator coil in embodiment of this invention. It is a figure which shows the 1st map used by the calculation process of the actual temperature estimated value of the stator coil in embodiment of this invention. It is a figure which shows the 2nd map used by the calculation process of the actual temperature estimated value of the stator coil in embodiment of this invention. It is a figure which shows the 3rd map used by the calculation process of the actual temperature estimated value of the stator coil in embodiment of this invention. It is a figure for demonstrating the calculation method of the deviation | shift amount (correction amount fluctuation | variation) in embodiment of this invention. It is a figure which shows an example of a structure of the temperature estimation system of the rotary electric machine in another embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating an example of a configuration of a temperature estimation system 10 for a rotating electrical machine according to the present embodiment. FIG. 1 also shows a battery 20, an inverter 22, a rotating electrical machine 30, and a cooling unit 50 in addition to the temperature estimation system 10 for the rotating electrical machine. The rotating electrical machine 30 is shown in a sectional view so that the configuration thereof can be understood. Has been.

  The rotating electrical machine 30 of this embodiment is mounted on an electric vehicle such as a hybrid vehicle or an electric vehicle. The rotating electrical machine 30 functions as a motor by power supplied from the battery 20 via the inverter 22 during power running to drive the wheels of the electric vehicle, and functions as a generator during braking to collect regenerative energy. The battery 20 is charged via The battery 20 is a secondary battery such as a lithium ion battery.

  As shown in FIG. 1, the rotating electrical machine 30 is housed in a case 48. The cooling unit 50 cools the components of the rotating electrical machine 30 including the stator coil 36 by supplying a refrigerant into the case 48. The refrigerant is, for example, a cooling oil called ATF (Automatic Transmission Fluid).

  The temperature estimation system 10 for a rotating electrical machine detects a control unit 12, a temperature sensor 40 (hereinafter referred to as a coil temperature sensor 40) that detects the temperature of a stator coil 36 of the rotating electrical machine 30, and a vehicle speed (vehicle speed). And a vehicle speed sensor 42. The control unit 12 includes a microprocessor, and functions as the actual temperature estimation unit 14 that estimates the actual temperature of the stator coil 36 (calculates an estimated actual temperature value) by executing a program. In addition, the control unit 12 includes a storage unit 18 that stores a map and the like used in a calculation process of an actual temperature estimated value of the stator coil 36 described later. The control unit 12 receives a detection temperature Tct of the coil temperature sensor 40 and a detection signal (vehicle speed v) of the vehicle speed sensor 42.

  In the temperature estimation system 10 of the rotating electrical machine according to the present embodiment, the actual temperature estimation unit 14 of the control unit 12 has a difference between the detected temperature Tct of the coil temperature sensor 40 and the actual temperature of the stator coil 36 at a predetermined cycle tc1. A correction amount for reducing or eliminating the temperature is calculated, and the detected temperature Tct of the coil temperature sensor 40 is corrected by the calculated correction amount to obtain an estimated actual temperature value of the stator coil 36. Details of this will be described later.

  Next, the configuration of the rotating electrical machine 30 will be described. As shown in FIG. 1, the rotating electrical machine 30 includes a rotor 32 and a stator 34. The rotor 32 is connected to a drive shaft 31 that is rotatably supported with respect to the case 48, and has a rotor core 33 provided on the outer peripheral portion of the drive shaft 31. The rotor core 33 is provided with a plurality of permanent magnets 39. The stator 34 includes a stator core 35. The stator core 35 is held by the case 48 in a state in which the inner peripheral side is spaced from the rotor 32 with a gap. A stator coil 36 is wound around each of a plurality of slots 37 provided in the stator core 35. A driving current is supplied to the stator coil 36 from the inverter 22, and the rotor 32 rotates with respect to the stator 34 by an electromagnetic force generated in the stator coil 36 by the driving current.

  A temperature sensor 40 (coil temperature sensor 40) that detects the temperature of the stator coil 36 is attached to the stator coil 36. As will be described later, the coil temperature sensor 40 is attached at a position where the coil temperature sensor 40 can be immersed in the refrigerant (it can be immersed in the refrigerant). The coil temperature sensor 40 is, for example, a thermistor. The detected temperature Tct of the coil temperature sensor 40 is output to the control unit 12. The coil temperature sensor 40 may be attached to the stator core 35 near the slot 37 around which the stator coil 36 is wound.

  Next, the configuration of the cooling unit 50 will be described. As shown in FIG. 1, the cooling unit 50 includes a refrigerant flow path 52 provided outside the case 48, and a refrigerant pipe 44 connected to the refrigerant flow path 52 and provided at the upper end inside the case 48. Yes. The refrigerant pipe 44 extends in the axial direction of the drive shaft 31. The refrigerant flow path 52 has a refrigerant pump 54, sucks the refrigerant F accumulated in the lower part of the case 48, and circulates and supplies it to the refrigerant pipe 44. The refrigerant pipe 44 has a plurality of jet outlets 46 through which the refrigerant F is jetted downward. By jetting the refrigerant F from the plurality of jet outlets 46, the refrigerant F contacts the stator coil 36 while flowing down. The stator coil 36 is cooled. The refrigerant F after cooling the stator coil 36 is again accumulated in the lower part of the case 48. Note that a cooling heat exchange unit may be provided in the cooling unit 50 to cool the refrigerant more effectively. The cooling heat exchange unit cools the refrigerant by exchanging heat between the air flowing outside and the refrigerant flowing inside.

  As described above, since the coolant is accumulated in the lower portion of the case 48, the coil temperature sensor 40 may or may not be immersed in the coolant (oil immersed in the coolant, depending on the speed of the vehicle). Not) FIG. 1 shows a state where the coil temperature sensor 40 is not immersed in the refrigerant. FIG. 2 is a diagram illustrating a state in which the coil temperature sensor 40 is immersed in the refrigerant. The same members as those illustrated in FIG. 1 are denoted by the same reference numerals. In order to increase the rotation efficiency of the rotating electrical machine 30, as the rotational speed of the rotating electrical machine 30, that is, the speed of the vehicle increases, the refrigerant is swept up by the gear, and the amount of the refrigerant below the case 48 decreases. That is, when the vehicle speed (vehicle speed) is high, the amount of refrigerant below the case 48 is reduced, and the coil temperature sensor 40 is not immersed in the refrigerant as shown in FIG. On the other hand, when the vehicle speed is slow, the amount of refrigerant below the case 48 increases, and the coil temperature sensor 40 is immersed in the refrigerant as shown in FIG.

  When the coil temperature sensor 40 is immersed in the refrigerant, a lower temperature is detected by the coil temperature sensor 40, and when the coil temperature sensor 40 is not immersed in the refrigerant, a higher temperature is detected by the coil temperature sensor 40. Is detected. That is, the state of deviation between the detected temperature Tct of the coil temperature sensor 40 and the actual temperature (actual temperature) of the stator coil 36 changes depending on the state of immersion of the coil temperature sensor 40 in the refrigerant (the presence or absence of immersion and the degree of immersion).

  Therefore, the temperature estimation system 10 for the rotating electrical machine according to the present embodiment takes into consideration the divergence state between the detected temperature Tct of the coil temperature sensor 40 and the actual temperature of the stator coil 36 that changes depending on the state of immersion of the coil temperature sensor 40 in the refrigerant. Then, by correcting the detected temperature Tct of the coil temperature sensor 40, an accurate actual temperature of the stator coil 36 is estimated (an estimated actual temperature value is obtained).

  Specifically, the estimated actual temperature value of the stator coil 36 is obtained as follows. As described above, the actual temperature estimating unit 14 of the temperature estimation system 10 for the rotating electrical machine calculates the estimated actual temperature value Tce of the stator coil 36 at a predetermined period tc1. The actual temperature estimation unit 14 uses the vehicle speed v (= V1) detected by the vehicle speed sensor 42 as an index representing the state of immersion of the coil temperature sensor 40 in the refrigerant (the presence or absence of immersion or the degree of immersion). When the vehicle speed V1 is a low value, the coil temperature sensor 40 is likely to be immersed in the refrigerant, and when the vehicle speed V1 is a high value, the coil temperature sensor 40 may not be immersed in the refrigerant. Means high. Then, the actual temperature estimation unit 14 calculates the difference Tn1 between the detected temperature Tct of the coil temperature sensor 40 (in the time interval tc1) and the actual temperature of the stator coil 36 per cycle corresponding to the vehicle speed V1, that is, the immersion state. calculate. In the present embodiment, the deviation amount Tn1 is also referred to as a correction amount variation Tn1. Then, the deviation integrated amount ITn is updated by adding the calculated deviation amount Tn1 (correction amount variation Tn1) to the integrated value (deviation integrated amount) ITn of the deviation amount up to the previous cycle, and the deviation integrated amount ITn is updated. Using the correction amount, the detected temperature Tct of the coil temperature sensor 40 is corrected, and an estimated actual temperature value of the stator coil 36 is obtained.

  Note that the amount of deviation Tn1 between the detected temperature Tct of the coil temperature sensor 40 (at the time interval tc1) and the actual temperature of the stator coil 36 per cycle is the detected temperature of the coil temperature sensor 40 (at the time interval tc1). And the torque command value TRQ of the rotating electrical machine 30 also vary. Therefore, in the present embodiment, the deviation amount Tn1 (correction amount variation Tn1) is changed in consideration of the change amount ΔTct and the torque command value TRQ, that is, according to the change amount ΔTct and the torque command value TRQ.

  Next, the calculation process of the estimated actual temperature value of the stator coil 36 performed by the actual temperature estimating unit 14 of the present embodiment will be described in detail. FIG. 3 is a flowchart showing an example of the flow of processing for calculating the estimated actual temperature value of the stator coil 36 performed by the actual temperature estimating unit 14. The actual temperature estimation unit 14 executes the flow of FIG. 3 at a predetermined cycle tc1. In the flow of FIG. 3, the actual temperature estimated value of the stator coil 36 is referred to as “coil actual temperature estimated value”.

  As shown in FIG. 3, first, in S100, the actual temperature estimation unit 14 acquires the detected temperature Tct of the coil temperature sensor 40. Next, in S102, the detected temperature PTct of the coil temperature sensor 40 obtained in the previous cycle is acquired. For example, PTct is stored in the storage unit 18 of the control unit 12 at the previous cycle and is obtained by reading it. Note that when the flow of FIG. 3 is executed for the first time, PTct may be set to the same value as Tct acquired in S100.

  Next, in S <b> 104, the actual temperature estimation unit 14 calculates a change amount ΔTct of the detected temperature of the coil temperature sensor 40. ΔTct is calculated by subtracting the detected temperature PTct of the previous cycle acquired in S102 from the detected temperature Tct of the current cycle acquired in S100. This ΔTct is the amount of change in the detected temperature Tct of the coil temperature sensor 40 (in the time interval tc1) per cycle.

  Next, in S106, the actual temperature estimation unit 14 acquires a torque command value TRQ of the rotating electrical machine 30. The torque command value TRQ is, for example, a torque value of the rotating electrical machine 30 calculated from a detection signal from an unillustrated accelerator pedal sensor or a vehicle speed sensor 42.

  After S106, in S108, the actual temperature estimation unit 14 uses the change amount ΔTct calculated in S104 and the torque command value TRQ acquired in S106 to determine a provisional deviation amount (temporary amount) from each of the plurality of maps. Get correction amount fluctuation). In the present embodiment, when the vehicle speed (vehicle speed) is a predetermined speed (Va and the like described later), the detected temperature Tct of the coil temperature sensor 40 per cycle (time interval tc1) and the stator coil 36 The temporary divergence amount is acquired using a map in which the actual temperature divergence amount is set. Specifically, the first map Ma in which the deviation amount Tna is set when the vehicle speed is Va, the second map Mb in which the deviation amount Tnb is set when the vehicle speed is Vb, and the vehicle speed is Vc. In this case, three maps are used together with the third map Mc in which the deviation amount Tnc is set. There is a relationship Va <Vb <Vc.

  4A is a diagram showing the first map Ma, FIG. 4B is a diagram showing the second map Mb, and FIG. 4C is a diagram showing the third map Mc. As shown in FIGS. 4A to 4C, a deviation amount corresponding to the change amount ΔTct of the detected temperature of the coil temperature sensor 40 and the torque command value TRQ is set in each map. These divergence amounts are examined in advance by experiments or the like in accordance with the change amount ΔTct of the detected temperature of the coil temperature sensor 40 and the torque command value TRQ at the vehicle speed (Va, Vb, Vc) of each map. It is set by that. Note that the deviation amount takes a positive or negative value. The first map Ma to the third map Mc are stored in the storage unit 18 of the control unit 12 in advance.

  In S <b> 108, the actual temperature estimation unit 14 acquires, from each map, a deviation amount associated with the detected temperature change amount ΔTct of the coil temperature sensor 40 and the torque command value TRQ as a temporary deviation amount. That is, the temporary deviation amount Tna is obtained from the first map Ma (FIG. 4A), the temporary deviation amount Tnb is obtained from the second map Mb (FIG. 4B), and the temporary deviation amount Tnc is obtained from the third map Mc (FIG. 4C). To do.

  In the present embodiment, the divergence amount (correction amount fluctuation) is set larger as the vehicle speed is slower (lower value), that is, as the possibility that the coil temperature sensor 40 is immersed in the refrigerant is higher. That is, when the first map Ma of Va, the second map Mb of Vb, and the third map Mc of Vc (Va <Vb <Vc) are compared with the same change amount ΔTct and the difference amount at the same torque command value TRQ. In general, the deviation amount of the first map Ma is the highest value, and the deviation amount of the third map Mc is the lowest value.

  In each map, the deviation amount is set to increase as the torque command value TRQ increases. In each map, the amount of deviation is set larger when the change amount ΔTct of the detected temperature of the coil temperature sensor 40 is negative than when it is positive.

  After the provisional deviation amount is acquired in S108 of FIG. 3, the process proceeds to S110. In S <b> 110, the actual temperature estimation unit 14 acquires the vehicle speed v (= V1), which is an index representing the immersion state of the coil temperature sensor 40 in the refrigerant, from the vehicle speed sensor 42.

  Next, in S112, the actual temperature estimation unit 14 calculates a deviation amount Tn1 corresponding to the vehicle speed V1 acquired in S110. That is, a deviation amount Tn1 (correction amount variation Tn1) between the detected temperature Tct of the coil temperature sensor 40 (at the time interval tc1) and the actual temperature of the stator coil 36 per cycle corresponding to the immersion state of the coil temperature sensor 40 in the refrigerant. ) Is calculated.

  FIG. 5 is a diagram for explaining a method of calculating the deviation amount Tn1. As shown in FIG. 5, the divergence amount Tn1 is calculated by linearly interpolating the values of the temporary divergence amounts Tna, Tnb, and Tnc acquired from each map in S108. Specifically, first, the relationship between each of the temporary divergence amounts Tna, Tnb, and Tnc and the vehicle speeds Va, Vb, and Vc of the maps from which they are read is expressed on the “vehicle speed v−deviation amount Tn” coordinate. Plot. Then, a divergence amount Tn1 corresponding to the vehicle speed V1 is calculated by linearly interpolating each plotted point.

  Next, in S114, the actual temperature estimation unit 14 updates the deviation integrated amount ITn. The deviation integrated amount ITn is obtained by integrating the deviation amounts calculated in each period. The actual temperature estimation unit 14 updates the deviation integrated amount ITn by adding the deviation amount Tn1 calculated in the current cycle to the deviation integrated amount ITn up to the previous cycle. The updated deviation integrated amount ITn becomes a correction amount for the detected temperature Tct of the coil temperature sensor 40.

  Next, in S116, the actual temperature estimation unit 14 corrects the detected temperature Tct by adding the deviation integrated amount ITn (corrected amount) obtained in S114 to the detected temperature Tct of the coil temperature sensor 40, and the stator temperature Tct is corrected. An estimated coil actual temperature value Tce of the coil 36 is calculated.

  The actual temperature estimation unit 14 performs the above-described calculation process of the actual temperature estimation value at a predetermined cycle tc1, thereby updating the coil actual temperature estimation value Tce.

  The calculated coil actual temperature estimated value Tce is used, for example, for setting the load factor (output limitation) of the rotating electrical machine 30. Specifically, when the coil actual temperature estimated value Tce becomes high temperature, the control unit 12 controls the inverter 22 to reduce the load factor of the rotating electrical machine 30, that is, performs output limitation, thereby rotating the rotating electrical machine. Protect 30 components.

  According to the temperature estimation system 10 of the rotating electrical machine of the embodiment described above, the coil temperature sensor 40 that estimates the immersion state (existence of immersion or degree of immersion) of the coil temperature sensor 40 in the refrigerant based on the vehicle speed and changes depending on the immersion state. Since the detection temperature Tct of the coil temperature sensor 40 is corrected in consideration of the deviation state between the detected temperature Tct of the stator and the actual temperature of the stator coil, an accurate actual temperature estimated value of the stator coil 36 can be obtained.

  Therefore, by limiting the output of the rotating electrical machine 30 using the estimated actual temperature value of the stator coil 36, the components of the rotating electrical machine 30 can be protected accurately, and the detected temperature Tct of the coil temperature sensor 40 and the stator coil 36 can be protected. Considering the deviation from the actual temperature, it is not necessary to limit the output with a large margin (perform excessive output limitation), so that the performance of the rotating electrical machine 30 can be sufficiently exerted.

  Moreover, according to the temperature estimation system 10 of the rotary electric machine of embodiment described above, in order to obtain the immersion state in the refrigerant | coolant of the coil temperature sensor 40, it is not necessary to newly provide a sensor etc., and wire harnesses, such as that sensor, etc. There is no need for wiring, and no dedicated circuit is required. Therefore, the system can be configured easily. In the temperature estimation system 10 of the rotating electrical machine of the embodiment described above, the vehicle speed is acquired by the vehicle speed sensor 42. However, when the vehicle speed can be grasped by means other than the vehicle speed sensor 42, the vehicle speed sensor 42 is provided. There may be no configuration.

  The temperature estimation system 10 of the rotating electrical machine according to the embodiment described above calculates the deviation amount Tn1 using three maps. However, the number of maps is not limited to three, and the deviation amount Tn1 may be calculated using another number of maps. Further, instead of using a map, a provisional deviation amount may be obtained by a calculation formula to calculate the deviation amount Tn1.

  The temperature estimation system 10 (10a) of the rotating electrical machine according to the embodiment described above uses the vehicle speed as an index representing the state of immersion of the coil temperature sensor 40 in the refrigerant. However, the number of rotations of the rotating electrical machine 30 (for example, the number of rotations of the rotor 32 of the rotating electrical machine 30 per minute) may be used as an index representing the state of immersion of the coil temperature sensor 40 in the refrigerant. FIG. 6 is a diagram illustrating an example of the configuration of the temperature estimation system 10 (10b) of the rotating electrical machine in the embodiment in which the rotational speed of the rotating electrical machine 30 is used as an index representing the state of immersion of the coil temperature sensor 40 in the refrigerant. The rotating electrical machine temperature estimation system 10b shown in FIG. 6 has the vehicle speed sensor 42 in the rotating electrical machine temperature estimation system 10a shown in FIG. 1 replaced with a rotational speed sensor 43. Otherwise, the rotating electrical machine temperature estimation system 10a shown in FIG. Same as the configuration. In FIG. 6, the same members as those shown in FIG.

  In the temperature estimation system 10b for the rotating electrical machine in FIG. 6, the detection signal of the rotational speed sensor 43 (the rotational speed rt of the rotating electrical machine 30) is input to the control unit 12. 6 uses the rotation speed of the rotating electrical machine 30 instead of the vehicle speed in the calculation process of the estimated actual temperature value of the stator coil 36 described with reference to FIGS. 3 to 5. That is, instead of the plurality of maps Ma to Mc corresponding to the difference in vehicle speed, a plurality of maps corresponding to the difference in the rotational speed of the rotating electrical machine 30 are prepared in advance. Then, in the calculation process of the estimated actual temperature value of the stator coil 36, provisional deviation amounts (temporary correction amount fluctuations) are obtained from each of those maps, and are obtained from the rotational speed sensor 43 using these provisional deviation amounts. A deviation amount (correction amount variation) corresponding to the rotation speed rt (= RT1) of the rotating electrical machine 30 is calculated. For example, when the rotation speed can be grasped from the electric power supplied to the rotating electrical machine 30, the rotation speed sensor 43 may not be provided.

  10, 10a, 10b Rotating electrical machine temperature estimation system, 12 control unit, 14 actual temperature estimating unit, 18 storage unit, 20 battery, 22 inverter, 30 rotating electrical machine, 31 drive shaft, 32 rotor, 33 rotor core, 34 stator, 35 Stator core, 36 stator coil, 37 slots, 39 permanent magnet, 40 temperature sensor (coil temperature sensor), 42 vehicle speed sensor, 43 speed sensor, 44 refrigerant pipe, 46 jet outlet, 48 case, 50 cooling section, 52 refrigerant flow path 54 Refrigerant pump.

Claims (1)

A rotating electrical machine mounted on a vehicle, the rotating electrical machine housed in a case, and a temperature estimation system for a rotating electrical machine having a stator coil cooled by being supplied with a refrigerant in the case,
A coil temperature sensor for detecting the temperature of the stator coil;
A correction amount for reducing or eliminating the deviation between the detected temperature of the coil temperature sensor and the actual temperature of the stator coil is calculated at a predetermined cycle, and the detected temperature of the coil temperature sensor is calculated based on the calculated correction amount. And an actual temperature estimation unit for obtaining an actual temperature estimated value of the stator coil by correcting
The coil temperature sensor is provided at a position where it can be immersed in the refrigerant,
The actual temperature estimator is
The correction amount that changes in accordance with the speed of the vehicle or the rotational speed of the rotating electrical machine that serves as an index indicating the immersion state of the coil temperature sensor in the refrigerant and the amount of change in the temperature detected by the coil temperature sensor is calculated. To
A temperature estimation system for a rotating electrical machine.

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