Cooling control device, electric power system, and cooling control method

Abstract

The present application avoids oil temperature misrecognition and appropriately controls the cooling capacity of the electric component. A control device that controls cooling of a rotating electric machine used for driving a vehicle has an arithmetic unit that performs a prescribed arithmetic process and a storage unit that the arithmetic unit can access, inputs first temperature information of a first temperature detection unit that detects a temperature of a first refrigerant that exchanges heat with the rotating electric machine, second temperature information of a second temperature detection unit that detects a temperature of a second refrigerant that exchanges heat with a winding of the rotating electric machine and is cooled by the first refrigerant, third temperature information of a rotating electric machine temperature detection unit that detects a temperature of the rotating electric machine, and fourth temperature information of an outside air temperature detection unit that detects a temperature of outside air, and verifies the second temperature information using the first temperature information, the second temperature information, the third temperature information, and the fourth temperature information.

Description

Technical Field

[0001] This invention relates to a cooling control device, and specifically to a technology for controlling the cooling device of a rotary motor used in electric vehicles. Background Technology

[0002] In so-called electric vehicles driven by rotating electric motors, it is necessary to cool the heat generated by the rotating electric motor. The cooling device for the rotating electric motor can be a combination of water cooling, which supplies cooling water to the water jacket by an electric water pump, and oil cooling, which supplies lubricating oil to the oil circuit by an electric oil pump, and a cooling device in which the lubricating oil is cooled by cooling water.

[0003] As background technology in this field, the following prior art exists. Patent Document 1 (Japanese Patent Application Publication No. 2006-174562) discloses a vehicle drive device comprising: an electric motor; a lubricating oil cooling unit disposed outside the electric motor and using cooling water to cool the lubricating oil of the electric motor; a cooling water circulation unit that circulates cooling water between the cooling water cooling unit and the electric motor and lubricating oil cooling unit via cooling water piping; and a lubricating oil circulation unit that circulates lubricating oil between the lubricating oil cooling unit and the electric motor via lubricating oil piping (see abstract).

[0004] Furthermore, Patent Document 2 (Japanese Patent Application Publication No. 2010-151282) discloses an anomaly determination device for a working oil temperature sensor with an anomaly determination unit. This anomaly determination unit determines an anomaly in the working oil temperature sensor that detects the working oil temperature of the transmission connected to the internal combustion engine of a vehicle. The anomaly determination device is characterized by having a coolant temperature sensor that detects the coolant temperature of the internal combustion engine. When the internal combustion engine is started after a predetermined time has elapsed since it stopped, the anomaly determination unit compares the coolant temperature detected by the coolant temperature sensor with the working oil temperature detected by the working oil temperature sensor. If the difference between the coolant temperature and the working oil temperature is above a threshold, the working oil temperature sensor is determined to be abnormal (see Technical Solution 1).

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2006-174562

[0008] Patent Document 2: Japanese Patent Application Publication No. 2010-151282 Summary of the Invention

[0009] The problem the invention aims to solve

[0010] Patent Document 1 describes the configuration of the cooling unit, but does not consider the operation when the refrigerant temperature (oil temperature) is misidentified. In addition, the device described in Patent Document 2 determines the abnormality based on the difference between the water temperature and the oil temperature, but due to other reasons (e.g., motor temperature, water temperature, external air temperature, etc.), it may sometimes lead to incorrect determination of the abnormality.

[0011] In particular, in drive systems where the motor and inverter are housed in a single enclosure, the output value of the oil temperature sensor located in the motor or gearbox may change due to noise generated by the inverter. If the cooling capacity of electric components such as the motor or inverter is mistakenly reduced due to such misinterpretation of oil temperature, the electric components may overheat, potentially leading to abnormal operation or damage.

[0012] Therefore, it is desirable to accurately determine whether the oil temperature reading is normal.

[0013] Technical means to solve the problem

[0014] A representative example of the invention disclosed in this application is as follows. Specifically, a control device for controlling the cooling of a rotary motor used for vehicle drive is characterized by comprising an arithmetic unit that performs predetermined arithmetic processing and a storage unit accessible to the arithmetic unit. It inputs first temperature information from a first temperature detection unit that detects the temperature of a first refrigerant that exchanges heat with at least the rotary motor, second temperature information from a second temperature detection unit that detects the temperature of a second refrigerant that exchanges heat with at least the windings of the rotary motor and is cooled by the first refrigerant, third temperature information from a rotary motor temperature detection unit that detects the temperature of the rotary motor, and fourth temperature information from an external air temperature detection unit that detects the temperature of the external air. The device verifies the second temperature information using the first temperature information, the second temperature information, the third temperature information, and the fourth temperature information.

[0015] The effects of the invention

[0016] According to the present invention, misidentification of oil temperature can be avoided, and the cooling capacity of the electric components can be appropriately controlled. The following description of embodiments will clarify the problems, configurations, and effects beyond those described above. Attached Figure Description

[0017] Figure 1 This is a block diagram illustrating a cooling device controlled by a cooling control device according to an embodiment of the present invention.

[0018] Figure 2 This is a flowchart illustrating the operation of the cooling control device according to an embodiment of the present invention.

[0019] Figure 3 This diagram illustrates the operation of a water pump controlled by a cooling control device according to an embodiment of the present invention.

[0020] Figure 4 This diagram illustrates the operation of an oil pump controlled by a cooling control device according to an embodiment of the present invention. Detailed Implementation

[0021] The rotary motor whose cooling is controlled by the cooling control device of this embodiment is a rotary motor suitable for use in automobiles. Among so-called electric vehicles that use rotary motors, there are hybrid electric vehicles (HEVs) that have both an engine and a rotary motor, and pure electric vehicles (EVs) that do not use an engine but only use a rotary motor to run. However, the rotary motor described below can be used in both types of automobiles.

[0022] Figure 1 This is a block diagram illustrating a cooling device controlled by a cooling control device according to an embodiment of the present invention, and a drive system cooled by the cooling device.

[0023] Figure 1 The drive system shown consists of a rotary motor 21, an inverter 60 that drives and controls the rotary motor 21, a heat sink 41, and a control device 50.

[0024] The rotary motor 21 and the gear assembly connected to the shaft of the rotary motor 21 are housed in the gearbox 11.

[0025] Although the internal structure of the rotary electric machine 21 is omitted from the illustration, a rotor is arranged on the inner circumference of the stator, which contains the windings. The rotary electric machine 21 can be a permanent magnet motor with permanent magnets, a synchronous motor with excitation windings, an induction motor with cage-like conductors, a reluctance rotary motor formed only by a rotor core, etc. The components used to generate a magnetic field from the rotor and their shapes are not limited. The windings can be composed of distributed windings or concentrated windings, and can be composed of either square or round wires. The winding method and type are not limited.

[0026] The rotating motor 21 generates a rotating magnetic field by transmitting current through its windings using the current and voltage output from the inverter 60, causing the rotor to rotate and generating torque. The rotor is connected to a gear assembly via a shaft, and the gear output shaft inside the gear assembly is connected to the axle, thereby reducing the speed of the rotating motor 21 and driving the vehicle. Alternatively, the rotating motor 21 may not be used for driving by converting electrical energy into the vehicle's kinetic energy, but rather for regenerating electrical energy from the vehicle's kinetic energy; it can also be used for both driving and regeneration purposes.

[0027] The heat generated by the current in the windings is cooled by media such as water and lubricating oil. A temperature sensor 22 is installed inside the rotating motor 21. The temperature sensor 22 measures the temperature of the rotating motor 21 (e.g., the windings) and outputs the measured winding temperature to the control device 50 and the inverter 60. The controller 50 adjusts the motor's cooling capacity based on the winding temperature. When the inverter 60 detects that the winding temperature is higher than a predetermined threshold, it controls the motor by reducing the current flowing through the windings to suppress the temperature rise of the rotating motor 21.

[0028] Lubricating oil is retained inside the gearbox 11, and a lubricating oil pipe 30 is provided to connect the lubricating oil between the rotary motor 21 and the gear assembly. The lubricating oil circulates within the rotary motor 21 via an oil pump 12 mounted on the lubricating oil pipe 30, lubricating and cooling the gears and the rotary motor 21. A temperature sensor 13 is installed inside the gearbox 11. The temperature sensor 13 measures the temperature of the lubricating oil and outputs the measured oil temperature to the control device 50.

[0029] A water passage 23 for cooling water is provided on the outer periphery of the rotating motor 21 (e.g., inside the frame). The water passage 23 is formed in a spiral or zigzag shape to improve the cooling efficiency of the rotating motor 21. The water passage 23 is connected to the radiator 41 via a cooling water pipe 40. The cooling water that has increased in temperature to cool the rotating motor 21 is circulated within the cooling water pipe 40 by a water pump 42 installed on the cooling water pipe 40, cooled by the radiator 41, and then returned to the rotating motor 21. The cooling water flowing through the water passage 23 cools the windings of the rotating motor 21 through the iron core of the frame and stator. In addition, the lubricating oil is cooled by cooling the entire frame, which can also cool the windings or bearings.

[0030] As shown in the figure, the cooling water piping 40 can also cool the inverter 60 via the inverter 60. Alternatively, a valve can be installed on the cooling water piping 40 to regulate the flow rate of the cooling water.

[0031] A temperature sensor 43 is installed on the cooling water pipe 40. The temperature sensor 43 measures the temperature of the cooling water and outputs the measured water temperature to the control device 50. The temperature sensor 43 can be installed on the cooling water pipe 40 near the outlet of the radiator 41 to measure the temperature of the cooling water that has become cold.

[0032] Temperature sensor 52 is located outside the drive system. Temperature sensor 52 measures the outside air temperature and outputs the measured outside air temperature to control device 50.

[0033] The vehicle control module 50 includes a cooling control device and controls the operation of the oil pump 12 and the water pump 42 (e.g., operation or stop, medium flow rate) based on the measurements of various temperature sensors 13, 43 and 52.

[0034] The control device 50 consists of a computer (microcomputer) including a computing unit, a memory, and input / output devices. The control device 50 can be installed separately from the inverter 60 or integrated with the inverter 60.

[0035] A computing device includes a processor that executes programs stored in memory. Part of the processing performed by the computing device executing the program may also be executed by other computing devices (such as hardware like FPGAs (Field Programmable Gate Arrays) or ASICs (Application Specific Integrated Circuits)).

[0036] The memory includes ROM and RAM, which are non-volatile storage elements. ROM stores immutable programs (such as BIOS). RAM is a high-speed, volatile storage element such as DRAM (Dynamic Random Access Memory), and a non-volatile storage element such as SRAM (Static Random Access Memory), storing programs executed by the arithmetic device and data used during program execution. The programs executed by the arithmetic device are stored in a non-volatile storage device that serves as a non-temporary storage medium for the control device 50.

[0037] Input / output devices are interfaces that send processed content to or receive data from external sources according to defined protocols.

[0038] The inverter 60 includes switching elements such as IGBT (Insulated Gate Bipolar Transistor) or SiC (Silicon Carbide), and drives the rotating motor 21 by controlling the voltage and current flowing through the windings of the rotating motor 21. The inverter 60, the rotating motor 21, and the gear assembly are configured within a housing 10.

[0039] Figure 2 This is a flowchart illustrating the operation of the cooling control device according to an embodiment of the present invention.

[0040] Figure 2The flowchart shown begins when the vehicle's ignition switch is turned on and power is supplied to the control unit 50 (100).

[0041] First, the control device 50 calculates the elapsed time t0 (101) from ignition off to ignition on. Next, it calculates the elapsed time t1 (102) from the disconnection of the main battery charging circuit to the reactivation of the ignition. This is because during the charging of the main battery, the charging circuit generates heat, and when the charging circuit is water-cooled, the cooling water is heated. Then, if the elapsed time t1 is short, the rising water temperature cannot be sufficiently reduced, the difference between the water temperature and the oil temperature increases, and condition (b) in step 105 (described later) is not met, increasing the likelihood of identifying an anomaly. Therefore, in step 102, if the elapsed time t1 is shorter than a predetermined threshold, the threshold T used for judgment in step 105 can be increased. WO .

[0042] Next, the control device 50 determines whether the temperature sensors 13, 22, 43, and 52 are abnormal (103). Abnormalities in the temperature sensors can be determined by checking whether the current flowing through the temperature sensor is within the normal range, whether the output value of the temperature sensor is within the normal range, and health check commands.

[0043] If temperature sensor 43 malfunctions, the water temperature cannot be measured. Therefore, control device 50 causes water pump 42 to operate in a restricted mode (120) and terminates the process. In the restricted mode of water pump 42, such as Figure 3 As shown, the water pump 42 is operated at the minimum value of the maximum rated output power within the operating temperature range.

[0044] Additionally, if the temperature sensor 22 malfunctions, the temperature of the windings of the rotary motor 21 cannot be measured. Therefore, the control device 50 limits the output of the rotary motor 21 (121), causing the water pump 42 to operate in continuous mode (122), thus ending the process. In the continuous mode of the water pump 42, such as Figure 3 As shown, this causes the water pump 42 to operate at its continuous rated output power. Figure 3 The lines in the continuous mode shown represent the logic values ​​that enable cooling when the water pump 42 operates at its continuous rated output power.

[0045] On the other hand, if the temperature sensor is normal, it is determined whether the measured value of the temperature sensor meets three conditions (a) to (c) (104 to 106).

[0046] In step 104, (a) the control device 50 determines whether the absolute value of the difference between the oil temperature measured by the temperature sensor 13 and the external air temperature measured by the temperature sensor 52 is less than the threshold T. AOIn step 105, (b) the control device 50 determines whether the absolute value of the difference between the oil temperature measured by temperature sensor 13 and the water temperature measured by temperature sensor 43 is less than the threshold T. WO In step 106, (c) the control device 50 determines whether the absolute value of the difference between the oil temperature measured by temperature sensor 13 and the winding temperature measured by temperature sensor 22 is less than a threshold T. MO .

[0047] Threshold T AO Threshold T WO Threshold T MO This value varies based on the elapsed time t0 from ignition off to ignition on, and can be defined as a function of t0. Alternatively, each threshold can be determined using a table that derives from t0. Furthermore, the threshold T... WO In addition to varying according to the elapsed time t0, it can also vary according to the elapsed time t1 from when the charging circuit is disconnected to when the ignition is turned on, and can be defined as a function of t0 and t1. Furthermore, a threshold T can be derived from t0 and t1. WO The table is used to determine the threshold T WO These thresholds can be determined based on the temperature difference during operation and the heat capacity of the object being measured (refrigerant or motor).

[0048] Then, the control device 50 determines whether two or more of conditions (a) to (c) are true (107). If two or more of conditions (a) to (c) are true, the control device 50 determines that the measured oil temperature is normal (108) and executes the processing after step 109. On the other hand, if two or more of conditions (a) to (c) are not true, the control device 50 determines that the measured oil temperature is abnormal (115) and executes the processing after step 116.

[0049] If a specified time elapses after the vehicle stops, the oil temperature, water temperature, and winding temperature converge to a value equal to the outside air temperature. Therefore, under the above conditions, the oil temperature is compared with several other temperatures (outside air temperature, water temperature, and winding temperature). If the difference is less than a specified threshold, the oil temperature can be considered to have been measured normally.

[0050] In addition, as a condition (d) that is different from the above conditions (a) to (c), the measured value of the oil temperature can also be verified by using the case where the difference between the temperature of the inverter 60 and the oil temperature of the lubricating oil is less than a specified threshold.

[0051] In step 109, after determining that the oil temperature measurement is normal, the control device 50 determines whether the oil temperature Tg measured by the temperature sensor 13 is lower than the threshold Tg1 (109). Then, if the oil temperature Tg measured by the temperature sensor 13 is higher than the threshold Tg1, the water pump 42 is operated in normal mode because the oil temperature Tg is high, and the lubricating oil is cooled with cooling water (117). In the normal mode of the water pump 42, as... Figure 3 As shown, the water pump 42 operates at its rated output power for a short time. Figure 3 The lines shown in the normal mode represent the logic values ​​that enable the water pump 42 to operate at its rated output power for a short period of time, allowing it to be cooled.

[0052] On the other hand, if the oil temperature Tg measured by temperature sensor 13 is lower than the threshold Tg1, the lubricating oil is sufficiently cooled, so control device 50 determines whether the winding temperature Tc measured by temperature sensor 22 is lower than the threshold Tc2 (110). Then, if the winding temperature Tc is above the threshold Tc2, control device 50 causes water pump 42 to operate in normal mode to cool the lubricating oil with cooling water (117). On the other hand, if the winding temperature Tc is lower than the threshold Tc2, control device 50 causes water pump 42 to operate in oil heating mode to raise the oil temperature (111). In the oil heating mode of water pump 42, such as Figure 3 As shown, when the water temperature is low and a large amount of heat is taken away from the lubricating oil, the flow rate of the cooling water in the water pump 42 is reduced so that the oil temperature rises to an appropriate level.

[0053] Then, the control device 50 determines whether the oil temperature Tg measured by the temperature sensor 13 is below the winding temperature Tc (112). If the oil temperature Tg is higher than the winding temperature Tc, it returns to step 111 and continues in the oil heating mode. On the other hand, if the oil temperature Tg is below the winding temperature Tc, the control device 50 causes the oil pump 12 to operate in normal mode, cooling the rotary motor 21 with lubricating oil (113). In the normal mode of the oil pump 12, as... Figure 4 As shown, oil pump 12 is activated only when the oil temperature is extremely low, and stopped in other temperature ranges.

[0054] Then, the control device 50 determines whether the oil temperature Tg measured by the temperature sensor 13 is above the threshold Tg1 (114). As a result, if the oil temperature Tg is below the threshold Tg1, it returns to step 110 and determines whether the winding temperature Tc is below the threshold Tc2. On the other hand, if the oil temperature Tg is above the threshold Tg1, it causes the water pump 42 to operate in normal mode and cools the lubricating oil with cooling water (117).

[0055] After step 117, the controller 50 determines whether the winding temperature Tc is lower than the upper limit temperature Ts of the coil (118). If the winding temperature Tc is above the upper limit temperature Ts, rapid cooling of the winding is required. Therefore, the control device 50 operates the oil pump 12 in maximum mode to maximize the cooling of the rotary motor 21 using lubricating oil (119), and the process ends. Conversely, if the winding temperature Tc is lower than the upper limit temperature Ts, the process ends.

[0056] If two or more of conditions (a) to (c) are not met, and the measured oil temperature is determined to be abnormal, then in step 116, the control device 50 causes the oil pump 12 to operate in a restricted mode, weakly cooling the rotary motor 21 with lubricating oil (116), and causes the water pump 42 to operate in normal mode, cooling the lubricating oil with cooling water (117). In the restricted mode of the oil pump 12, as Figure 4 As shown, the oil pump 12 is operated at the minimum value of the maximum rated output power within the operating temperature range.

[0057] As explained above, the cooling control device 50 of the embodiments of the present invention uses first temperature information (cooling water temperature) of a first refrigerant that exchanges heat with at least the rotating motor 21, second temperature information (lubricating oil temperature) of a second refrigerant that exchanges heat with at least the windings of the rotating motor 21 and is cooled by the first refrigerant, third temperature information (temperature of the rotating motor 21), and fourth temperature information (temperature of the outside air) to verify the second temperature information (oil temperature). Therefore, it can avoid misidentification of the oil temperature and appropriately control the cooling capacity of the electric components. That is, even in the event of an oil temperature identification anomaly, such as the temperature sensor 13 outputting a temperature lower than the actual oil temperature, it can maintain water cooling capacity, maintain the necessary minimum vehicle driving performance, and prevent overheating of the rotating motor 21 and the inverter 60.

[0058] Furthermore, the second temperature information (oil temperature) is verified based on the first temperature parameter calculated using the second temperature information (oil temperature) and the fourth temperature information (outdoor air temperature), the second temperature parameter calculated using the second temperature information (oil temperature) and the first temperature information (coolant temperature), and the third temperature parameter calculated using the second temperature information (oil temperature) and the third temperature information (winding temperature). Therefore, the misidentification of oil temperature can be correctly detected, and the cooling capacity of the electric components can be appropriately controlled.

[0059] Additionally, the difference between the second temperature information (oil temperature) and the fourth temperature information (outdoor air temperature) and the threshold T are calculated. AO The comparison results include the first temperature parameter (condition (a)), the difference between the second temperature information (oil temperature) and the first temperature information (coolant temperature), and the threshold T. WOThe comparison results include the second temperature parameter (condition (b)) and the difference between the second temperature information (oil temperature) and the third temperature information (winding temperature) and the threshold T. MO The third temperature parameter (condition (c)) of the comparison result is determined to be normal if at least two of the calculated first temperature parameter, second temperature parameter and third temperature parameter meet the specified conditions. Therefore, by using the external air temperature, cooling water temperature and winding temperature as comparison objects, the determination of misidentification of oil temperature based on majority decision can be correctly determined.

[0060] In addition, the threshold T is changed based on the elapsed time t0 from when the control device 50 stops to when it restarts. AO Threshold T WO Threshold T MO Therefore, it can take into account the temperature drop of coolant or lubricating oil when the vehicle is stationary to set a threshold, and can correctly detect false identification of oil temperature.

[0061] In addition, the charging circuit that uses the first refrigerant (cooling water) to cool the battery that supplies power to the opposing rotary motor 21 is adjusted based on the elapsed time t1 from when the charging circuit stops until the control device 50 starts. WO Therefore, it is possible to set a threshold based on the heating of the cooling water according to the operation of the charging circuit, and to correctly detect misidentification of oil temperature.

[0062] Furthermore, the rotating motor 21 and the inverter 60 are housed in a housing 10. The second temperature detection unit (temperature sensor 13) and the rotating motor temperature detection unit (temperature sensor 22) are disposed in the housing 10. Therefore, the temperature sensor 13 is susceptible to noise. It is possible to detect the oil temperature misidentification caused by the noise from the inverter 60 contained in the oil temperature measured by the temperature sensor 13.

[0063] Furthermore, since the first temperature detection unit (temperature sensor 43) is located outside the housing 10, the cooling water temperature measured by the temperature sensor 43, which has minimal noise impact from the inverter 60, can be used to correctly detect misidentification of oil temperature.

[0064] Furthermore, the present invention is not limited to the embodiments described above, but includes various modifications and equivalent configurations within the spirit of the appended claims. For example, the embodiments described above are provided in detail for ease of understanding and illustration of the invention, and the invention is not limited to structures possessing all the described configurations. Additionally, a portion of the configuration of one embodiment may be replaced with the configuration of another embodiment. Furthermore, the configuration of another embodiment may be added to the configuration of one embodiment. Additionally, for a portion of the configuration of each embodiment, other configurations may be added, deleted, or replaced.

[0065] Furthermore, the aforementioned components, functions, processing units, and processing units can be partially or entirely implemented in hardware by designing with integrated circuits, or they can be implemented in software by having a processor interpret and execute programs that perform their respective functions.

[0066] Information such as programs, tables, and files that perform various functions can be stored in storage devices such as memory, hard disk, SSD (Solid State Drive), or recording media such as IC card, SD card, DVD, and BD.

[0067] Furthermore, the description of control lines and information lines as necessary does not necessarily imply the installation of all necessary control lines and information lines. In reality, it can be assumed that almost all components are interconnected.

[0068] Symbol Explanation

[0069] 10 Housing, 11 Gearbox, 12 Oil pump, 13 Temperature sensor, 21 Rotary motor, 22 Temperature sensor, 23 Water circuit, 30 Lubricating oil piping, 40 Cooling water piping, 41 Radiator, 42 Water pump, 43 Temperature sensor, 50 Control device, 52 Temperature sensor, 60 Inverter.

Claims

1. A control device for controlling the cooling of a rotary electric motor used in vehicle drive, characterized in that, It has an arithmetic unit that performs the prescribed arithmetic operations and a storage unit that can be accessed by the arithmetic unit. The following information was entered: First temperature information from a first temperature detection unit that detects the temperature of at least the first refrigerant that exchanges heat with the rotary motor; The second temperature information of the second temperature detection unit that detects the temperature of the second refrigerant that exchanges heat with at least the windings of the rotary motor and is cooled by the first refrigerant; Third temperature information from the rotating motor temperature detection unit that detects the temperature of the rotating motor; as well as The fourth temperature information is from the external air temperature detection unit, which measures the temperature of the outside air. Calculate a first temperature parameter representing the comparison result of the difference between the second temperature information and the fourth temperature information and a predetermined first threshold, a second temperature parameter representing the comparison result of the difference between the second temperature information and the first temperature information and a predetermined second threshold, and a third temperature parameter representing the comparison result of the difference between the second temperature information and the third temperature information and a predetermined third threshold. If at least two of the calculated first temperature parameter, second temperature parameter, and third temperature parameter meet the specified conditions, the second temperature information is determined to be normal. The first threshold, the second threshold, and the third threshold are changed based on the elapsed time from when the control device stops to when it restarts.

2. The control device according to claim 1, characterized in that, The first refrigerant cools the charging circuit, which charges the battery that supplies power to the rotating motor. The second threshold is changed based on the elapsed time from when the charging circuit stops until the control device starts.

3. The control device according to claim 1, characterized in that, The power conversion circuit that supplies power to the rotary motor and the rotary motor are housed within a single housing. The second temperature detection unit and the rotary motor temperature detection unit are disposed inside the housing.

4. The control device according to claim 3, characterized in that, The first temperature detection unit is disposed outside the housing.

5. An electric system, characterized in that, have: The control device according to claim 1 or 2; The rotary motor; and A power conversion circuit section that supplies power to the rotary motor.

6. The electric system according to claim 5, characterized in that, The rotary motor and the power conversion circuit are housed within a single housing. The second temperature detection unit and the rotary motor temperature detection unit are disposed inside the housing.

7. The electric system according to claim 6, characterized in that, The first temperature detection unit is disposed outside the housing.

8. A cooling control method, executed by a control device for controlling the cooling of a rotary motor used for driving a vehicle, characterized in that, The control device has an arithmetic unit that performs prescribed arithmetic operations and a storage unit that the arithmetic unit can access. The method includes: The computing unit receives first temperature information from a first temperature detection unit that detects the temperature of at least the first refrigerant that exchanges heat with the rotating motor. The computing unit receives second temperature information from a second temperature detection unit that detects the temperature of a second refrigerant that exchanges heat with at least the windings of the rotating motor and is cooled by the first refrigerant. The computing unit receives third temperature information from the rotating motor temperature detection unit, which detects the temperature of the rotating motor. The computing unit receives fourth temperature information from the external air temperature detection unit, which detects the temperature of the external air. The arithmetic unit calculates a first temperature parameter representing the comparison result of the difference between the second temperature information and the fourth temperature information and a predetermined first threshold, a second temperature parameter representing the comparison result of the difference between the second temperature information and the first temperature information and a predetermined second threshold, and a third temperature parameter representing the comparison result of the difference between the second temperature information and the third temperature information and a predetermined third threshold. If at least two of the calculated first temperature parameter, second temperature parameter, and third temperature parameter meet the specified conditions, the second temperature information is determined to be normal. The first threshold, the second threshold, and the third threshold are changed based on the elapsed time from when the control device stops to when it restarts.

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