JP5553097B2 - Rotating electrical machine system controller - Google Patents

Description

  The present invention relates to a rotating electrical machine system control apparatus for a rotating electrical machine using a cooling medium.

  In vehicles using a rotating electrical machine as a drive source, such as a hybrid vehicle and an electric vehicle, the rotating electrical machine and the driving device of the rotating electrical machine are usually cooled to prevent overheating of the rotating electrical machine and a driving device such as an inverter that drives the rotating electrical machine. A cooling system is installed. A general cooling system includes a cooling water circulation path, a pump that circulates the cooling water in the circulation path, and a radiator that cools the cooling water.

  In the prior art, in order to prevent a failure due to overheating of a rotating electrical machine or the like, control for limiting the output of the rotating electrical machine may be performed based on the operating temperature of the rotating electrical machine or the like. For example, in Patent Document 1, in a vehicle drive system including a drive system including a drive motor and an inverter, and a cooling device that cools the drive system, the temperature of the inverter and the cooling water cooled by the radiator of the cooling device are disclosed. A technique for limiting the output of a drive motor based on a difference from temperature is disclosed. In the technique described in Patent Document 1, when the difference between the inverter temperature and the cooling water temperature is small, it is determined that the cooling capacity of the cooling device is low, and the output of the drive motor is limited.

  There is also a technique for determining whether or not an abnormality has occurred in the cooling system. For example, there is a conventional technique that detects the temperature of cooling water in the cooling system and determines that an abnormality has occurred in the cooling system when the detected temperature exceeds a predetermined threshold. Further, for example, in Patent Document 2, in a cooling device mounted on an electronic device, when the rotational speed of a pump that circulates a liquid refrigerant in a circulation path exceeds a predetermined threshold, the amount of liquid refrigerant in the cooling device A technique for determining that is insufficient is disclosed.

JP 2006-149064 A JP 2006-250395 A

  With the technique described in Patent Document 1, the occurrence of an abnormality in the cooling device is not detected only by limiting the output of the drive motor in accordance with the cooling capacity of the cooling device that is obtained using the temperature of the cooling water. Therefore, in the vehicle drive system described in Patent Document 1, even when some abnormality occurs in the cooling device and the temperature of the cooling water becomes high, processing for coping with the generated abnormality is performed. There is nothing.

  In addition, the prior art for determining whether or not an abnormality has occurred based on the temperature of the cooling water in the cooling system, and the technology described in Patent Document 2, the liquid refrigerant based on the rotational speed of the pump that circulates the liquid refrigerant. The technique for determining the shortage of the liquid amount can determine whether or not an abnormality has occurred in the cooling system, but it is difficult to determine what abnormality has occurred in which part of the cooling system.

  The following means contribute to solving at least one of the above problems.

A rotating electrical machine system control device according to the present invention includes a rotating electrical machine, a driving device for the rotating electrical machine, a circulation path for cooling liquid that cools the rotating electrical machine and the driving apparatus, and circulates the cooling liquid through the circulation path. A rotary electric machine system control device that controls a rotary electric machine system including a water pump, the liquid temperature of the cooling liquid obtained from a liquid temperature sensor provided in the circulation path of the cooling liquid, and the rotation of the water pump And a control unit that controls the drive device and the water pump based on the number of rotations of the water pump when the liquid temperature of the coolant is equal to or higher than a preset threshold value. there classify whether a value within a preset constant range as the rotation speed during steady operation of the water pump, outside of the normal range, in the case in the normal range, the cooling When the heat exchange apparatus is abnormal among the elements included in the cooling system including the circulation path and the water pump that circulates the coolant in the circulation path, and is outside the steady range, Comparing a plurality of predetermined rotation speed threshold ranges with the rotation speed of the water pump, and depending on the corresponding rotation speed threshold range, abnormalities in elements included in the cooling system other than the heat exchange device a determining unit that determines a type, based on the result of the judgment, characterized by chromatic and a fail-safe processing unit for controlling the drive device and the water pump.

In the rotating electrical machine system control device according to another aspect of the present invention, the fail-safe processing unit is determined based on the liquid temperature when the determination processing unit determines that the heat exchange device is abnormal. It is preferable to control the driving device so that the output torque of the rotating electrical machine is equal to or less than the output torque limit value.

Further, in the rotating electrical machine system control device according to another aspect of the present invention, the drive device is provided with an element temperature sensor that detects the temperature of each of the plurality of circuit elements included in the drive device, and the determination process parts are rotational speed of the front Symbol water pump, an outer of said stationary range, if it is within the lower range over between the upper and lower limit values determined in advance as a range wider than the normal range, It is determined that the circulation path is blocked, and the fail-safe processing unit uses, for each of the plurality of circuit elements, each temperature in the circulation path using a temperature acquired from an element temperature sensor provided in the driving device. obtains the estimated fluid temperature of the cooling fluid through the portion closest to the circuit element, before Symbol plurality of circuit elements output that is determined based on the estimated fluid largest estimated fluid temperature of the temperature determined for each It is preferable to control the drive device so that the output torque of the rotating electrical machine becomes less torque limit value.

  As described above, in the aspect in which the output torque of the rotating electrical machine is limited based on the maximum estimated liquid temperature among the estimated liquid temperatures obtained for each of the plurality of circuit elements included in the drive device, the plurality of circuit elements Since the control is performed according to the circuit element considered to have the highest load among them, the drive device can be appropriately protected.

In another rotating electric machine system control device of one aspect of the present invention, the determination processing section, the rotation speed of the previous SL water pump, an outer of the steady range, predetermined as a range wider than the normal range A sufficient amount of the coolant for cooling is present in the circulation path when it is greater than a second threshold value that is greater than or equal to the upper limit value of the upper and lower limit range between the upper limit value and the lower limit value. Preferably, the fail-safe processing unit performs control to stop the water pump.

In another one embodiment the rotary electric machine system controller of the present invention, the determination processing section, the rotation speed of the previous SL water pump is greater than 0, and a outside of the steady range, than the normal range An abnormality relating to the water pump occurs when the value is equal to or smaller than a third threshold value set in advance as a value smaller than the lower limit value of the upper and lower limit range between the upper limit value and the lower limit value set in advance as a wide range. It is preferable that the fail-safe processing unit performs control to make the rotation speed of the water pump larger than the current rotation speed.

The rotating electric machine system control device according to another aspect of the present invention, the determination processing unit, when the rotation speed of the front Symbol water pump is 0, it is determined that the water pump is faulty, the fail The safe processing unit uses, for each of the plurality of circuit elements, a temperature acquired from an element temperature sensor provided in the driving device, and an estimated liquid temperature of the coolant passing through a portion closest to each circuit element in the circulation path. look, prior Symbol plurality of circuit elements each for the obtained the estimated fluid temperature of up to the estimated fluid temperature wherein said drive device so that the output torque becomes the rotating electrical machine below the output torque limit value is determined based on Is preferably controlled.

  Moreover, in the rotating electrical machine system control device according to the present invention, the control unit may perform the control performed in the plurality of aspects of the present invention described above in combination.

  ADVANTAGE OF THE INVENTION According to this invention, the rotary electric machine system control apparatus which can perform the appropriate fail safe process in a rotary electric machine system according to the kind of abnormality which generate | occur | produced in the cooling system can be provided.

It is a block diagram of a rotary electric machine system provided with the rotary electric machine system control apparatus in embodiment of this invention. It is a figure which shows the example of the detail of a structure of the inverter 18 of FIG. It is a flowchart which shows the example of the procedure of the abnormality determination process performed in embodiment of this invention. It is a table | surface which shows the example of the content of the abnormal mode judgment process and fail safe process performed in embodiment of this invention. It is a figure which shows the example of the allowable torque electric current of a rotary electric machine with respect to the temperature of a cooling fluid. It is a figure which shows the example of the element temperature rise degree with respect to the electric current which flows into a circuit element.

  FIG. 1 is a block diagram illustrating a schematic example of a rotating electrical machine system including a rotating electrical machine system control device. The rotating electrical machine system illustrated in FIG. 1 includes a rotating electrical machine 16, an inverter 18, and a cooling system that cools the rotating electrical machine 16 and the inverter 18. The cooling system included in the rotating electrical machine system illustrated in FIG. 1 includes a coolant circulation path 10, a water pump 12, and a radiator 14.

  The ECU (Electronic Control Unit) 20 is a control unit that is mounted on a vehicle and controls operations of the rotating electrical machine system and the cooling system based on information from each sensor, as will be described later, and is a rotating electrical machine system control device. The ECU 20 can be realized using a microcomputer or the like. A part of the function of the ECU 20 functions as a rotating electrical machine system control device or a cooling system control device according to one embodiment of the present invention.

  The rotating electrical machine 16 is, for example, a drive motor for a hybrid vehicle (HV, Hybrid Vehicle) or an electric vehicle (EV, Electric Vehicle). The rotating electrical machine 16 may be a motor that is connected to an engine of a hybrid vehicle and functions as a generator that generates electric power by the rotational force of the engine or an electric motor that can start the engine. Although not shown in FIG. 1, the rotating electrical machine system may include a plurality of rotating electrical machines 16. For example, a rotating electrical machine system mounted on a hybrid vehicle includes a vehicle drive motor and a motor that receives power from the engine and generates power or starts the engine.

  The inverter 18 constitutes a part of a drive device for the rotating electrical machine 16. Inverter 18 converts a DC voltage supplied from a DC power supply (not shown) into an AC voltage in accordance with control signal PWM from ECU 20 to drive rotating electrical machine 16. The inverter 18 may be configured as one collective part (ASSY) by combining a plurality of module parts. For example, the inverter 18 may include an inverter module having a function of driving the rotating electrical machine 16 and a converter module that converts a voltage level of a DC power source (not shown). Further, for example, when the rotating electrical machine system includes a plurality of rotating electrical machines 16, the inverter 18 includes an inverter module that drives each rotating electrical machine 16.

  FIG. 2 shows an example of the inverter 18 when the rotating electrical machine system includes three rotating electrical machines 16a, 16b, and 16c. In FIG. 2, for example, the rotating electrical machine 16a is a driving motor that drives the front wheels of the vehicle, the rotating electrical machine 16b is a driving motor that drives the rear wheels of the vehicle, and the rotating electrical machine 16c exchanges power with an engine (not shown). This is a motor for generating power or starting an engine. Referring to FIG. 2, inverter 18 includes inverter modules INV1, INV2, and INV3 that drive rotating electrical machines 16a, 16b, and 16c, respectively. The inverter modules INV1, INV2, and INV3 drive the rotating electrical machines 16a, 16b, and 16c in accordance with control signals PWM1, PWM2, and PWM3 from the ECU 20, respectively.

  In FIG. 2, inverter 18 includes converter modules CNV1 and CNV2. The converter modules CNV1 and CNV2, for example, convert the voltage level of a supply voltage from a DC power supply (not shown) and supply it to a load such as the inverter modules INV1, INV2 and INV3 or an auxiliary battery (not shown), It functions as a step-down circuit that regenerates the generated power to a DC power supply. Converter modules CNV1 and CNV2 operate according to control signals SC1 and SC2 from ECU 20, respectively. The number of modules included in the inverter 18 is increased or decreased according to the characteristics of the rotating electrical machine system, such as the number of rotating electrical machines 16 included in the rotating electrical machine system.

  Referring again to FIG. 1, the water pump 12 is a pump that circulates the coolant in the circulation path 10. The water pump 12 rotates according to the rotational speed command value DR from the ECU 20. The radiator 14 is a heat exchange device that cools the coolant by releasing the heat of the coolant passing through the circulation path 10. Referring to FIG. 1, the coolant in the circulation path 10 of the cooling system flows in the order of the water pump 12, the rotating electrical machine 16, the radiator 14, and the inverter 18 in the direction of the solid line arrow.

  Hereinafter, processing performed by the ECU 20 in the control of the rotating electrical machine system described with reference to FIGS. 1 and 2 will be described.

The ECU 20 acquires torque command values TR1, TR2, and TR3 that specify output torques of the rotating electrical machines 16a, 16b, and 16c from an external ECU or the like. Further, the ECU 20 obtains currents MCRT1, MCRT2, and MCRT3 flowing through the rotary electric machines 16a, 16b, and 16c from current sensors (not shown) provided in the rotary electric machines 16a, 16b, and 16c, and is provided in the converter modules CNV1 and CNV2. Currents I _CNV1 and I _CNV2 flowing through the converter modules CNV1 and CNV2 are obtained from the current sensor (not shown).

Referring to FIG. 2, each module INV1, INV2, INV3, CNV1, CNV2 of the inverter 18 is provided with element temperature sensors 24a, 24b, 24c, 24d, 24e for detecting the temperature of the circuit elements in each module. It is done. The ECU ₂₀ acquires the temperatures T _INV1 , T _INV2 , T _INV3 , T _CNV1 , and T _CNV2 of the circuit elements in each module detected by the element temperature sensors 24a, 24b, 24c, 24d, and 24e, respectively.

Further, in the coolant circulation path 10, a liquid temperature sensor 22 for detecting the temperature of the coolant passing through the inverter 18 is provided in the vicinity of the coolant inlet to the inverter 18 (FIG. 2). The liquid temperature sensor 22 is provided in a portion that is not easily affected by the heat generated by each module of the inverter 18. The liquid temperature sensor 22 may be provided not in the vicinity of the inverter 18 but in the vicinity of the coolant outlet from the radiator 14 in the circulation path 10, for example. ECU20 obtains the coolant temperature T _W of the liquid temperature sensor 22 has detected.

  The ECU 20 generates control signals PWM1, PWM2, PWM3, SC1, and SC2 for controlling each module of the inverter 18 based on the above-described signals acquired from various sensors provided in the rotating electrical machine system, and generates the generated signals. It transmits to the inverter 18. Each module of the inverter 18 operates according to a control signal received from the ECU 20.

Further, the ECU 20 transmits a rotational speed command value DR to the water pump 12. The rotational speed command value DR is usually a constant value set in advance. ECU20 is liquid temperature sensor 22 for detecting the temperature of the coolant may transmit the rotation speed command value DR in accordance with the coolant temperature T _W detected. For example, the temperature range of the coolant cold, medium temperature, and is divided into three ranges of high temperature, it may be set a rotation speed command value DR for each temperature range in advance, enter the detected coolant temperature T _W The rotational speed command value DR set corresponding to the temperature range may be transmitted to the water pump 12.

  Further, the ECU 20 acquires the actual rotational speed R of the water pump 12 from the water pump 12, and performs an abnormality determination process for the cooling system based on the acquired actual rotational speed R. Hereinafter, the abnormality determination process performed by the ECU 20 will be described with reference to FIG.

  FIG. 3 is a flowchart illustrating an example of a procedure of abnormality determination processing performed by the ECU 20.

When the operation of the vehicle is started, the ECU 20 starts the process shown in FIG. Referring to FIG. 3, first, in step S1, ECU 20 obtains a coolant temperature T _W of the liquid temperature sensor 22 has detected. Next, in step S2, the ECU 20 determines whether or not the acquired coolant temperature T _W exceeds a preset threshold value θ _W. If the coolant temperature T _W exceeds the threshold θ _W , the process proceeds to step S3, and if not, the process returns to step S1.

The threshold value θ _W used in step S2 is a threshold value for determining whether or not the temperature of the coolant in the cooling system is normal. The threshold value θ _W is determined based on, for example, the outside air temperature in an environment where a vehicle equipped with a rotating electrical machine system is used. For example, when a rotating electrical machine system is mounted on a vehicle used in an area where the maximum outside temperature is considered to be about 40 ° C., the threshold θ _W is set to 65 ° C., and the maximum outside temperature is about 50 ° C. When the rotating electrical machine system is mounted on a vehicle used in an area considered to be at ° C, the temperature may be set at 75 ° C. A value obtained by adding a detection error (for example, 10 ° C.) of the liquid temperature sensor 22 to the threshold value of the coolant temperature determined based on the outside air temperature may be used as the threshold θ _W.

  In step S3, the ECU 20 acquires the actual rotational speed R of the water pump 12. Next, in step S4, the ECU 20 determines an abnormal mode of an abnormality that has occurred in the cooling system, based on the actual rotational speed R acquired in step S3.

  The table of FIG. 4 shows an example of the contents of the abnormal mode determined in step S4. In the table of FIG. 4, the first column shows conditions for the actual rotational speed R of the water pump 12. The second column of the table of FIG. 4 shows the abnormal mode when the conditions of each row (1 to 6) are satisfied for the actual rotational speed R of the water pump 12. The contents of the third column in the table of FIG. 4 will be described in detail later.

  Hereinafter, the abnormal mode determination process in step S4 will be described with reference to FIG.

When the actual rotational speed R of the water pump 12 is a value in the steady range θ _NL ≦ R ≦ θ _NU set in advance as the rotational speed during steady operation (row 1), the ECU 20 sets the cooling system in step S4. It is determined that an abnormality has occurred in the radiator 14. Here, the steady range θ _NL ≦ R ≦ θ _NU of the rotational speed during steady operation is the range of the actual rotational speed expected for the rotational speed command value DR. For example, the lower limit value θ _NL = (1 + 0.1) DR of the steady range and the upper limit value θ _NU = (1−0.1) DR of the steady range are set. When the actual rotational speed R is within the steady range in step S4, it is considered that the coolant temperature is rising in the cooling system despite the coolant circulating in the circulation path 10. It can be determined that a heat exchange abnormality has occurred in the radiator 14. For example, the fan of the radiator 14 may be out of order.

When the actual rotational speed R of the water pump 12 is a value θ _H1 <R <θ _H2 that is larger than the steady range (line 2), in step S4, the ECU 20 closes the circulation path 10 of the cooling system. Judge that The range of this value is set to the lower limit value θ _H1 = (1.2 + 0.1) DR and the upper limit value θ _H2 = (1.2−0.1) DR, for example. Further, for example, the actual rotational speed with respect to the rotational speed command value DR is measured under a blocked state artificially created in the circulation path 10 of the cooling system, and the lower limit value θ _H1 and the upper limit value θ _H2 are calculated using the measured values. You may decide.

When the actual rotational speed R of the water pump 12 is larger than the threshold value θ _H3 that is equal to or greater than the upper limit value θ _H2 of the range of values in the row 2 (row 3), in step S4, the ECU 20 causes the cooling system to operate normally. It is determined that a sufficient amount of coolant does not exist in the circulation path 10. This threshold value θ _H3 is set to about 1.5 times the rotational speed command value DR, for example. The threshold value θ _H3 may be determined, for example, by measuring the actual rotational speed R with respect to the rotational speed command value DR in a state where the circulation path 10 is not filled with the coolant, and using this measured value. If the actual rotational speed R is larger than the threshold value θ _{H3 in} step S4, the coolant in the circulation path 10 is reduced due to, for example, coolant leakage from the circulation path 10, and the water pump 12 is idling. It is done.

When the actual rotational speed R of the water pump 12 is greater than 0 and less than or equal to the threshold value θ _L that is smaller than the lower limit value θ _{NL of the} steady range (line 4), the ECU 20 has an abnormality with respect to the water pump 12 in step S4. Judge that you are doing. The threshold value θ _L is set to a value that is 0.8 times the rotational speed command value DR, for example. In the cooling system, when the circulation path 10 is blocked, the actual rotation speed R with respect to the rotation speed command value DR of the water pump 12 is temporarily reduced at the initial stage where the circulation path 10 is blocked, and then the actual rotation speed R is again measured. It is known that the rotational speed R increases. It is desirable to set the threshold value θ _L as a value smaller than the actual rotational speed R obtained in the initial stage when the circulation path 10 is closed. If the threshold value θ _L is set to a value smaller than the actual rotational speed at the initial stage of the blockage of the circulation path 10, the abnormality of the water pump 12 is determined to be different from the blockage of the circulation path 10 in the determination of the abnormal mode in step S4. Separately, it can be judged more accurately. If the actual rotational speed R is in the range of 0 <R ≦ θ _L in step S4, for example, the motor shaft of the water pump 12 is worn and the actual rotational speed expected for the rotational speed command value DR It is conceivable that the condition cannot be obtained. Further, for example, due to an abnormality in the signal line connecting the ECU 20 and the water pump 12, the water pump 12 receives a signal having a level lower than the signal level of the rotational speed command value DR transmitted by the ECU 20 as the rotational speed command value DR. In some cases, software abnormalities may have occurred.

  When the actual rotational speed R of the water pump 12 is 0 (line 5), the ECU 20 determines in step S4 that the water pump 12 has failed.

When the actual rotational speed R of the water pump 12 does not satisfy any of the conditions of the rows 1 to 5 (row 6), in step S4, the ECU 20 suspends the determination of the abnormal mode. For example, when the actual rotational speed R is larger than the threshold value θ _L used in the row 4 of the table of FIG. 4 and smaller than the lower limit value θ _{NL of the} steady range, the actual rotational speed R is changed from the first line to the fifth line. Neither condition is satisfied. Further, for example, when the threshold value θ _{H1 in} row 2 of the table of FIG. 4 is set larger than the upper limit value θ _NU of the steady range, the actual rotational speed R is between the upper limit value θ _{NU of the} steady range and the threshold value θ _H1. And when the threshold value θ _H3 of the row ₃ is set larger than the threshold value θ _{H2 of the} row 2 and the actual rotational speed R is a value between the threshold value θ _H2 and the threshold value θ _H3 . However, the actual rotational speed R does not satisfy any of the conditions from the first row to the fifth row.

  After the abnormal mode determination process in step S4, it is determined in step S5 whether or not an abnormal mode has been specified. If ECU 20 has identified an abnormal mode in step S4 (row 1 to row 5 in the table of FIG. 4), in step S5, the process proceeds to step S6. If ECU 20 has suspended the determination of the abnormal mode in step S4 (row 6 in the table of FIG. 4), the process returns to step S1 in step S5.

  In step S6, ECU20 performs the fail safe process according to the conditions of the actual rotation speed R of the water pump 12 about a rotary electric machine system. The third column of the table of FIG. 4 shows the contents of the process performed in step S6 according to the conditions established for the actual rotational speed R of the water pump 12. The process performed in step S6 is a fail-safe process suitable for the abnormal mode determined in step S4.

When the actual rotational speed R of the water pump 12 is in the steady range (θ _NL ≦ R ≦ θ _NU ) (line 1), in step S6, the ECU 20 is based on the coolant temperature T _W acquired from the fluid temperature sensor 22. Processing for limiting the output torque of the rotating electrical machines 16a, 16b, and 16c is performed. For example, as shown in FIG. 5, the ECU 20 holds a map (not shown) that determines the maximum allowable torque current of the rotating electrical machines 16a, 16b, and 16c with respect to the coolant temperature. Referring to FIG. 5, when the coolant temperature is equal to or lower than the limit start temperature T _lim , the allowable torque current is 100%. When the coolant temperature exceeds the limit start temperature T _lim , the allowable torque current is the maximum temperature T It decreases linearly so that _max is 0%.

ECU20 is restricted, and acquires the allowable torque current corresponding to the coolant temperature T _W from the map of FIG. 5, the rotary electric machine 16a according to the obtained allowable torque current, 16b, the torque command value TR1, TR2, TR3 for 16c , The control signals PWM1, PWM2, PWM3 for controlling the rotating electrical machines 16a, 16b, 16c are generated. ECU20, among the torque command value TR1, TR2, TR3 received from an external ECU, when there is a torque command value greater than the permissible torque current corresponding to the coolant temperature T _W, the permissible torque current as the torque command value Set the value. Thereafter, the control signals PWM1, PWM2, and PWM3 are generated so that the outputs indicated by the torque command values TR1, TR2, and TR3 are obtained in the rotating electrical machines 16a, 16b, and 16c, and the modules INV1, INV2, and the inverter 18 are respectively generated. Send to INV3. If the allowable torque current corresponding to the coolant temperature T _W is 100%, ECU 20 does not perform the restriction of the torque command value, each of the rotary electric machine 16a, 16b, at 16c, the received torque command value TR1, TR2 , TR3 are generated so as to obtain the output indicated by TR3.

In the map of FIG. 5, the limit start temperature T _lim and the maximum temperature T _max are set so that the element temperature of the circuit element included in the inverter 18 does not exceed the allowable maximum value. For the circuit elements included in the inverter 18, for example, as shown in FIG. 6, the element temperature rise ΔT with respect to the value of the current flowing through the circuit elements is known, and the ECU 20 determines the element temperature as illustrated in FIG. 6. A map of the rising degree is held in the storage device. Usually, the temperature of the circuit element is considered to be substantially equal to the coolant temperature T _W in the circulation path 10, so the sum of the element temperature rise ΔT and the coolant temperature T _W when a certain current flows is the current. It can be said that this is the element temperature of the circuit element when. Therefore, the element temperature rise of the case 100% of the current flows through the circuit element and [Delta] T _max, [Delta] T _max and the coolant temperature T _w and the sum that is equal to the allowable maximum value of the temperature of the circuit elements of the cooling The liquid temperature T _W may be set as the limit start temperature T _lim . Then, as long as the coolant temperature T _w is equal to or lower than the limit start temperature T _lim , the temperature of the circuit element does not exceed the allowable maximum value even if a current of 100% is supplied to the circuit element. Furthermore, when the maximum temperature T _max = T _lim + ΔT _max is set at 0% of the allowable torque current, when the coolant temperature T _W reaches the maximum allowable temperature of the circuit element, the current flowing through the circuit element is 0, that is, the element temperature rise ΔT = 0, and the temperature of the circuit element does not exceed the allowable maximum value.

Referring to FIG. 4 again, when the actual rotational speed R of the water pump 12 is θ _H1 <R <θ _H2 (line 2), the ECU 20 detects the element temperature sensor provided in each module of the inverter 18 in step S6. 24a to 24e are used to calculate the estimated liquid temperature of the coolant passing through the portion closest to each module in the circulation path 10, and limit the output torque of the rotating electrical machines 16a, 16b, and 16c based on the calculated estimated liquid temperature. Process.

First, in the circuit 10 based on the detected temperatures of the temperature sensors 24a to 24e provided in each module of the inverter 18 and the current values MCRT1, MCRT2, MCRT3, I _CNV1 , and I _CNV2 of each module of the inverter 18. The estimated liquid temperature of the coolant passing through the portion closest to each module of the inverter 18 is calculated. The ECU 20 uses the current values MCRT1, MCRT2, MCRT3, I _CNV1 , and I _CNV2 acquired from the current sensor as the current values flowing through the circuit elements of the modules INV1, INV2, INV3, CNV1, and CNV2 of the inverter 18, for example, as shown in FIG. From such a map, the element temperature rise ΔT of each circuit element corresponding to each current value is obtained. Next, a value obtained by subtracting the element temperature increase ΔT obtained for each element from the detected temperatures T _INV1 , T _INV2 , T _INV3 , T _CNV1 , and T _{CNV2 of} the element temperature sensors 24a to 24e is obtained in each circuit in the circuit 10. The estimated liquid temperature of the coolant passing through the part closest to Thereafter, an allowable torque current corresponding to the highest estimated liquid temperature among the obtained estimated liquid temperatures is obtained from the map of FIG. The ECU 20 performs a process similar to the output torque limiting process described with respect to the case of row 1 in the table of FIG. 4 according to the allowable torque current corresponding to the maximum estimated liquid temperature, and the output torque of the rotating electrical machines 16a, 16b, and 16c. Limit.

In the case of row 2 in the table of FIG. 4 (θ _H1 <R <θ _H2 ), since the circulation path 10 is considered to be blocked, it is considered that the flow of the coolant in the circulation path 10 is stopped. In this state, for example, when some modules of the inverter 18 are operating and other modules are not operating, the temperature of the coolant passing through the portion closest to the operating module in the circulation path 10 is This is considered to be higher than the temperature of the coolant passing through the portion closest to the module that is not. Accordingly, when the output torque limiting process of the rotating electrical machines 16a, 16b, and 16c is performed using the estimated liquid temperature of the coolant that passes through the portion closest to each module of the inverter 18 in the circulation path 10 as in the process described above. The inverter 18 and the rotating electrical machines 16a, 16b, and 16c can be protected appropriately.

When the coolant is flowing normally in the circulation path 10, the portion closest to each module of the inverter 18 in the circulation path 10 compared to the case where the coolant flow in the circulation path 10 is stopped. The difference that occurs between the temperatures of the coolant passing through is small. Therefore, when the actual rotational speed R of the water pump 12 is in the constant range (row 1), the rotary electric machine 16a based on the coolant temperature T _W of the liquid temperature sensor 22 detects, as described above, 16b, 16c of An output torque limiting process is performed.

When the actual rotational speed R of the water pump 12 is larger than the threshold value θ _H3 (line 3), the ECU 20 performs control to stop the water pump 12 in step S6. For example, a control signal for setting the rotational speed command value DR = 0 is transmitted to the water pump 12. Stopping the water pump 12 prevents the water pump 12 from overheating.

When the actual rotational speed R of the water pump 12 is greater than 0 and equal to or less than the threshold value θ _L (line 4), in step S6, the ECU 20 performs control to make the rotational speed of the water pump 12 larger than the current rotational speed. . For example, the ECU 20 transmits a rotational speed command value DR having a larger value than the current value to the water pump 12. By increasing the rotation speed of the water pump 12, the coolant flow rate in the circulation path 10 of the cooling system can be brought close to a steady value.

  When the actual rotational speed R of the water pump 12 is 0 (line 5), the ECU 20 is provided in each module of the inverter 18 in step S6, similarly to the fail-safe process in the case of line 2 in the table of FIG. Based on the estimated coolant temperature calculated using the element temperature sensors 24a to 24e, processing for limiting the output torque of the rotating electrical machines 16a, 16b, and 16c is performed. The state of the cooling system when the actual rotational speed R of the water pump 12 is 0 is the same as the state of the cooling system in the case of row 2 in that the coolant does not flow in the circulation path 10. The same fail-safe process as in 2 is performed.

  In the fail-safe process in each case (step S6 in FIG. 3), the ECU 20 may perform a process of displaying the specified abnormal mode on a display device (not shown). In addition, when the determination of the abnormal mode is suspended in step S4, the ECU 20 performs a process of displaying an abnormality occurrence in the cooling system on a display device (not shown) before executing the process of step S1 after the determination in step S5. Also good.

In the embodiment described above, the fail-safe process in the step S6, the actual rotational speed R and the output of the rotary electric machine based on the coolant temperature T _W of the liquid temperature sensor 22 detects the case of the constant range of the water pump 12 Torque limiting processing is performed, and when the actual rotational speed R is θ _H1 <R <θ _H2 and R = 0, the rotating electrical machine is based on the estimated coolant temperature calculated using the detected temperatures of the element temperature sensors 24a to 24e. The output torque limiting process is performed. In other embodiments, even when the actual rotational speed R is within the steady range, the detected temperatures of the element temperature sensors 24a to 24e are used as in the case of θ _H1 <R <θ _H2 and R = 0. The output torque limiting process of the rotating electrical machine may be performed based on the calculated estimated liquid temperature.

  In the embodiment described above, in the output torque limiting process of the rotating electrical machine based on the estimated liquid temperature calculated using the detected temperatures of the element temperature sensors 24a to 24e, the maximum estimated among the estimated liquid temperatures calculated. Using the liquid temperature, the allowable torque current of all the rotary electric machines 16a, 16b, 16c provided in the rotary electric machine system is uniformly determined. In another embodiment, based on each element temperature sensor 24a, 24b, 24c provided in each inverter module INV1, INV2, INV3 which controls each rotary electric machine 16a, 16b, 16c, of rotary electric machine 16a, 16b, 16c. The allowable torque current may be determined for each, and the output torque of each rotating electrical machine 16a, 16b, 16c may be limited according to the determined allowable torque current.

  DESCRIPTION OF SYMBOLS 10 Circulation path, 12 Water pump, 14 Radiator, 16a, 16b, 16c Rotary electric machine, 18 Inverter, 20 ECU, 22 Liquid temperature sensor, 24a, 24b, 24c, 24d, 24e Element temperature sensor.

Claims (6)

Controlling a rotating electrical machine system including a rotating electrical machine, a driving device for the rotating electrical machine, a circulation path for cooling liquid that cools the rotating electrical machine and the driving apparatus, and a water pump that circulates the cooling liquid in the circulation path. A rotating electrical machine system control device,
A controller for controlling the driving device and the water pump based on the liquid temperature of the cooling liquid obtained from a liquid temperature sensor provided in the circulation path of the cooling liquid and the rotational speed of the water pump;
The controller is
When the liquid temperature of the coolant is equal to or higher than a preset threshold value, the rotation speed of the water pump is a value within a steady range preset as the rotation speed at the time of steady operation of the water pump, or Among the elements included in the cooling system, which is classified as out of the steady range, and includes the coolant circulation path and the water pump that circulates the coolant through the circulation path when within the steady range. When the heat exchange device is determined to be abnormal in the above-described case, and when the heat exchange device is outside the steady range, the predetermined rotation speed threshold range is compared with the rotation speed of the water pump, and the corresponding rotation speed threshold value is compared. In accordance with the range, a determination processing unit for determining the type of abnormality of the elements included in the cooling system other than the heat exchange device,
Based on the determined result, a fail-safe processing unit that controls the driving device and the water pump;
The rotary electric machine system controller, characterized in that the have a. In the rotating electrical machine system control device according to claim 1,
The fail-safe processing unit is
When the determination processing unit determines that there is an abnormality in the heat exchange device, the drive device is controlled so that the output torque of the rotating electrical machine is equal to or less than an output torque limit value determined based on the liquid temperature. A rotating electrical machine system control device. In the rotating electrical machine system control device according to claim 1,
The drive device is provided with an element temperature sensor that detects the temperature of each of the plurality of circuit elements included in the drive device,
The determination processing section,
Rotational speed of the front Symbol water pump, an outer of said stationary range, if it is within the lower range over between the upper and lower limit values determined in advance as a range wider than the normal range, the circulation path Is determined to be blocked,
The fail-safe processing unit is
For each of the plurality of circuit elements, using a temperature obtained from the element temperature sensor provided in the drive device, it obtains the estimated fluid temperature of the cooling fluid through the portion nearest to the respective circuit elements in the circulation path, before Symbol Controlling the driving device so that the output torque of the rotating electrical machine is equal to or less than an output torque limit value determined based on a maximum estimated liquid temperature among the estimated liquid temperatures obtained for each of a plurality of circuit elements. A rotating electrical machine system control device. In the rotating electrical machine system control device according to claim 1 ,
The determination processing unit
Rotational speed of the front Symbol water pump, an outer of the steady range, advance as the upper limit value or more values of the upper and lower limit range between the upper limit value and the lower limit value determined in advance as a range wider than the normal range Determining that there is not a sufficient amount of the coolant in the circuit for cooling if greater than a predetermined second threshold;
The fail-safe processing unit is
A rotating electrical machine system control device that performs control to stop the water pump. In the rotating electrical machine system control device according to claim 1 ,
The determination processing unit
Rotational speed of the front Symbol water pump is greater than 0, and a outside of the steady range, the lower limit of the lower range over between the upper and lower limit values determined in advance as a range wider than the normal range When the value is equal to or smaller than a third threshold value set in advance as a value smaller than the value, it is determined that an abnormality relating to the water pump has occurred,
The fail-safe processing unit is
A rotating electrical machine system control device that performs control to make the rotational speed of the water pump larger than a current rotational speed. In the rotating electrical machine system control device according to claim 1 ,
The determination processing unit
When the rotation speed of the front Symbol water pump is 0, it is determined that the water pump is faulty,
The fail-safe processing unit is
For each of the plurality of circuit elements, using a temperature obtained from the element temperature sensor provided in the drive device, it obtains the estimated fluid temperature of the cooling fluid through the portion nearest to the respective circuit elements in the circulation path, before Symbol Controlling the driving device so that the output torque of the rotating electrical machine is equal to or less than an output torque limit value determined based on a maximum estimated liquid temperature among the estimated liquid temperatures obtained for each of a plurality of circuit elements. A rotating electrical machine system control device.

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