JP2009011062A - Motor cooling device, and control method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To cool a motor by driving an oil pump and to suppress a driver from being given any sense of incompatibility caused by the drive noises of the pump. <P>SOLUTION: When motor temperatures Tm1, Tm2 are less than a threshold value T and more than a threshold value T2, it is judged whether the motor temperatures Tm1, Tm2 and the vehicle speed V are within a range to turn on the oil pump 46 or not, whether the engine is operated or not, and whether the cooling fan for supplying air to the oil cooler provided in the circulation passage of the cooling oil is driven or not (S140 to S160), and when it is judged that the motor temperatures Tm1, Tm2 and the vehicle speed V are in the range to turn on the oil pump 46, the engine is operated and the cooling fan is also driven, the oil pump is turned on (S120). Thereby the motor can be cooled and the noises due to the driving of the pump can be masked by the background noises based on the vehicle speed V, the operation of the engine 22 and the driving of the cooling fan to suppress a driver from being given any sense of incompatibility. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a cooling device that cools an electric motor that is mounted on a vehicle and driven when outputting driving power using cooling oil, and a control method thereof.

Conventionally, this type of electric motor cooling device is driven by an oil pump motor that pumps cooling oil to the motor when the temperature of the electric motor mounted on the vehicle is equal to or higher than a predetermined temperature, and the oil is cooled when the temperature of the electric motor is lower than the predetermined temperature. One that stops the driving of the pump motor has been proposed (see, for example, Patent Document 1). In this apparatus, the oil pump motor is driven only when the temperature of the electric motor is equal to or higher than a predetermined temperature, so that useless energy consumption can be suppressed and the electric motor can be efficiently cooled.
JP-A-4-145801

  However, in the above-described cooling device, although the electric motor can be cooled, the oil pump is driven regardless of the operation of the driver, and therefore the driver feels uncomfortable due to the noise accompanying the driving of the oil pump. There is.

  An object of the motor cooling device and the control method thereof according to the present invention is to cool the motor and prevent the driver from feeling uncomfortable due to abnormal noise. Another object of the motor cooling device and the control method thereof according to the present invention is to suppress efficient cooling of the motor.

  The motor cooling device and the control method thereof according to the present invention employ the following means in order to achieve at least a part of the above-described object.

The motor cooling device of the present invention is:
A cooling device that cools an electric motor that is mounted on a vehicle and that is driven when driving power is output using cooling oil,
Heat exchange means for cooling the cooling oil by heat exchange with outside air;
A pumping means provided in a cooling oil circulation path including the electric motor and the heat exchange means, and circulating the cooling oil in the circulation path by pumping the cooling oil;
Temperature detecting means for detecting the temperature of the electric motor;
Noise reflection state detection means for detecting a noise reflection state as a state reflecting the degree of noise based on running;
Control means for controlling the pumping means so that the electric motor is cooled in a state in which the noise based on running becomes a predetermined level or higher based on the detected temperature of the electric motor and the detected noise reflection state. Is the gist.

  In the motor cooling device according to the present invention, the motor is cooled in a state where the noise based on the traveling is equal to or higher than a predetermined level based on the temperature of the motor and the noise reflecting state reflecting the degree of the noise based on the traveling. The pressure feeding means is controlled. Therefore, since the noise accompanying the driving of the pressure feeding means is masked by the noise based on the running, it is possible to cool the electric motor and suppress the driving of the pressure feeding means from giving an uncomfortable feeling to the driver.

  In such a motor cooling device of the present invention, the noise reflection state detecting means may be means for detecting a vehicle speed.

  In the motor cooling device of the present invention mounted on a vehicle equipped with an internal combustion engine, the noise reflection state detection means may be means for detecting an operating state of the internal combustion engine.

  Furthermore, the motor cooling device of the present invention may further include a blowing unit that blows air toward the heat exchange unit, and the noise reflection state detection unit is a unit that detects a driving state of the blowing unit. it can.

  Further, in the motor cooling device of the present invention, the motor is arranged so that the motor is cooled by traveling wind, and the control means is configured to detect the detected motor as the vehicle speed increases when the vehicle speed is equal to or higher than a predetermined vehicle speed. It may be a means for controlling the pressure-feeding means so that the pressure-feeding means becomes difficult to be driven with respect to temperature. In this way, useless energy can be suppressed and the motor can be efficiently cooled.

  In the motor cooling device of the present invention, the control unit controls the pressure feeding unit to be driven regardless of the detected noise reflection state when the detected temperature of the motor is equal to or higher than a predetermined temperature. It can also be a means. In this way, overheating of the electric motor can be suppressed.

The cooling device control method of the present invention includes:
A heat exchange means for cooling the cooling oil by heat exchange with the outside air, and a cooling oil circulation passage including an electric motor and the heat exchange means. The cooling oil is pumped to supply the cooling oil to the circulation passage. A control method of a cooling device comprising pressure feeding means for circulation in the interior,
Controlling the pumping means so that the motor is cooled in a state in which the noise based on traveling is equal to or higher than a predetermined level based on the temperature of the motor and a noise reflection state as a state reflecting the degree of noise based on traveling. It is characterized by.

  According to the control method of the cooling device of the present invention, the motor is operated in a state where the noise based on traveling is equal to or higher than a predetermined level based on the temperature of the motor and the noise reflecting state as a state reflecting the degree of noise based on traveling. The pumping means is controlled to be cooled. Therefore, since the noise accompanying the driving of the pressure feeding means is masked by the noise based on the running, it is possible to cool the electric motor and suppress the driving of the pressure feeding means from giving an uncomfortable feeling to the driver.

  Next, the best mode for carrying out the present invention will be described using examples.

  FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 10 equipped with a motor cooling device as an embodiment of the present invention. The hybrid vehicle 10 according to the embodiment includes an engine 12 that is operated and controlled by an engine electronic control unit (engine ECU) 14, and a ring gear that is connected to a crankshaft of the engine 12 and a drive shaft that is coupled to a front axle. Is connected to the planetary gear mechanism 16, the sun gear of the planetary gear mechanism 16 is a motor MG1 capable of generating power, the motor MG2 is connected to the drive shaft and is capable of generating power, and the radiator 34. Cooling for an engine having a cooling water pump 36 that circulates cooling water in a cooling water circulation path 32 that circulates between the radiator 34 and the engine 12 and an electric cooling fan 38 that blows air to the radiator 34 based on the temperature of the cooling water. As a lubrication cooling medium for lubricating and cooling the circulation system 30 and the motors MG1 and MG2. Comprising oil and motor cooling circulation system 40 for cooling the, with the hybrid electronic control unit 50 that controls the whole vehicle, the. The motors MG1 and MG2 are driven with charging / discharging of the battery 24 by switching control of the switching elements of the inverters 21 and 22 as drive circuits thereof by the motor electronic control unit (motor ECU) 20.

  The motor cooling circulation system 40 is disposed in front of the vehicle and cools the oil by heat exchange with the outside air. The oil cooler 44 is connected to the oil cooler 44 in parallel with the motors MG1 and MG2. An oil circulation path 42 that circulates oil between the motors MG1 and MG2, and an oil pump 46 that circulates oil through the oil circulation path 42 by pumping oil from the motors MG1 and MG2 to the oil cooler 44 side. In addition, the cooling fan 38 in the engine cooling circulation system 30 described above can send air to the oil cooler 44 of the motor cooling circulation system 40 in addition to the radiator 34, and is requested from the hybrid electronic control unit 50. Is controlled by the engine ECU 14. Further, the motor MG1 and the motor MG2 are arranged so that the traveling wind is introduced as the vehicle travels, and are cooled by the traveling wind together with the motor cooling circulation system 40.

  The hybrid electronic control unit 50 is configured as a microcomputer centered on a CPU 52. In addition to the CPU 52, a ROM 54 that stores processing programs, a RAM 56 that temporarily stores data, an input / output port (not shown), and communication Provide a port. The hybrid electronic control unit 50 includes motor positions Tm1 and Tm2 from temperature sensors 60 and 62 attached to the motors MG1 and MG2, and a shift position SP from a shift position sensor 72 that detects an operation position of the shift lever 71, respectively. Accelerator opening degree Acc from the accelerator pedal position sensor 74 that detects the amount of depression of the accelerator pedal 73, brake pedal position BP from the brake pedal position sensor 76 that detects the amount of depression of the brake pedal 75, vehicle speed V from the vehicle speed sensor 78, etc. Is input via the input port. The hybrid electronic control unit 50 outputs a drive signal to the oil pump 46 and the like via an output port. As described above, the hybrid electronic control unit 50 is connected to the engine ECU 14 and the motor ECU 20 via the communication port, and exchanges various control signals and data with the engine ECU 14 and the motor ECU 20.

  The thus configured hybrid vehicle 10 of the embodiment calculates a required torque to be output to the drive shaft based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 73 by the driver, and this required torque. The engine 14, the motor MG1, and the motor MG2 are controlled to operate so that the required power corresponding to is output to the drive shaft. Further, in the hybrid vehicle 10 of the embodiment, the condition for automatic stop of the engine 22 is satisfied when the vehicle required power set according to the driver's depression of the accelerator pedal 83 becomes less than the first predetermined value. When the engine 22 is automatically stopped and the engine 22 is being operated, the required vehicle power set according to the depression of the accelerator pedal 83 by the driver is greater than or equal to a second predetermined value greater than the first predetermined value. When the condition for automatic start of the engine 22 is satisfied, the engine 22 that has been automatically stopped is automatically started. Note that the operation control of the hybrid vehicle 10 does not form the core of the present invention, and thus detailed description thereof is omitted.

  Here, the motor cooling device of the embodiment includes a motor cooling circulation system 40 including an oil circulation path 42, an oil cooler 44, and an oil pump 46, temperature sensors 60 and 62 attached to the motors MG1 and MG2, and The electronic control unit 50 for hybrid is comprised.

  Next, the operation of the motor cooling device of the embodiment configured in this manner will be described. FIG. 2 is a flowchart showing an example of a cooling processing routine executed by the hybrid electronic control unit 50. This routine is repeatedly executed every predetermined time.

  When the cooling processing routine is executed, first, the CPU 52 of the hybrid electronic control unit 50 first determines the motor temperatures Tm1 and Tm2 from the temperature sensors 60 and 62, the vehicle speed V from the vehicle speed sensor 78, the operating state of the engine 22, the cooling fan. A process of inputting data such as the driving state 38 is executed (step S100). Here, the operating state of the engine 22 and the driving state of the cooling fan 36 communicate from the engine ECU 24 the value of a flag that is turned on / off depending on whether the engine 22 is operating or the value of a flag that is turned on / off depending on whether the cooling fan 38 is driven. It was supposed to be entered by

  When the data is input in this way, the input motor temperatures Tm1 and Tm2 are compared with the threshold values T1 and T2 (steps S110 and S120). Here, the threshold values T1 and T2 are set as starting temperatures of the oil pump 46, and the threshold value T2 is determined as a temperature lower than the threshold value T1, such as 150 ° C. and 130 ° C., respectively. When either of the motor temperatures Tm1 and Tm2 is equal to or higher than the threshold T1, it is determined that the oil pump 46 should be driven immediately, and the oil pump 46 is turned on so that the oil is pumped to the motors MG1 and MG2 (step S130). End the routine.

  When both of the motor temperatures Tm1 and Tm2 are less than the threshold value T1 and greater than or equal to the threshold value T2, it is determined whether or not the motor temperatures Tm1 and Tm2 and the vehicle speed V are within the region where the oil pump 46 should be turned on (step S140). . In this embodiment, in this embodiment, the relationship between the motor temperatures Tm1, Tm2, the vehicle speed V, and the on / off state of the oil pump 46 is obtained in advance and stored in the ROM 56 as a map, and the motor temperatures Tm1, Tm2 and the vehicle speed are based on this map. It is determined whether or not V is in the region where the oil pump 46 should be turned on. An example of this map is shown in FIG. As shown in the figure, when the motor temperatures Tm1 and Tm2 are less than the threshold value T1 and greater than or equal to the threshold value T2, the oil pump 46 is turned off when the vehicle speed V is less than the predetermined vehicle speed Vref, and when the vehicle speed V is greater than or equal to the predetermined vehicle speed Vref. The motor temperatures Tm1 and Tm2 that are turned on from OFF are determined to gradually increase from the threshold value T2 to the threshold value T1. The map is defined in this manner in order to cool the motors MG1 and MG2 because the driving sound of the oil pump 46 can be masked by noise (background noise) due to running when the vehicle speed V is equal to or higher than the predetermined vehicle speed Vref. Even if the oil pump 46 is driven, the driving sound does not give the driver a sense of incongruity, and if the vehicle speed V further increases, the motors MG1 and MG2 are cooled by the traveling wind without driving the oil pump 46. Based on what can be expected.

  If it is determined that the motor temperatures Tm1, Tm2 and the vehicle speed V are not within the region where the oil pump 46 should be turned on, it is determined whether or not the engine 22 is in operation (step S150). It is determined that the driving sound of the oil pump 46 is masked by noise (dark noise) accompanying the operation of the engine 22, the oil pump 46 is turned on (step S120), and this routine is terminated.

  When the engine 22 is not in operation, it is further determined whether or not the cooling fan 38 is in operation (step S160). When the cooling fan 38 is in operation, the oil pump 46 is caused by noise (dark noise) associated with the driving of the cooling fan 38. Is determined to be masked, the oil pump 46 is turned on (step S120), and this routine is terminated.

  When it is determined in step S130 that both of the motor temperatures Tm1 and Tm2 are lower than the threshold value T2, it is not necessary to cool the motors MG1 and MG2, and either of the motor temperatures Tm1 and Tm2 is determined to be lower than the threshold value T1 and equal to or higher than the threshold value T2. However, when the motor temperature Tm1, Tm2 and the vehicle speed V are not within the region where the oil pump 46 is to be turned on and the engine 22 is not being operated and the cooling fan 38 is not being driven, when the oil pump 46 is turned on, operation is performed with the driving sound. It is determined that the person feels uncomfortable, the oil pump 46 is turned off (step S170), and this routine is terminated.

  According to the motor cooling device 20 of the embodiment described above, whether or not the motor temperatures Tm1 and Tm2 and the vehicle speed V are within the region where the oil pump 46 should be turned on, whether or not the engine 22 is in operation, By determining whether or not the fan 38 is being driven, the oil pump 46 is driven in a state where the background noise becomes equal to or higher than a predetermined level. Therefore, the motors MG1 and MG2 are cooled and the driver generates noise due to driving of the oil pump 46. It is possible to prevent the user from feeling uncomfortable. Further, when the motor temperatures Tm1 and Tm2 are less than the threshold value T2, the oil pump 46 is turned off, so that useless energy consumption can be suppressed and the motors MG1 and MG2 can be efficiently cooled. Of course, when the motor temperatures Tm1 and Tm2 are equal to or higher than the threshold value T1, the oil pump 46 is turned on. Therefore, it is possible to prevent the motors MG1 and MG2 from overheating and causing problems.

  In the motor cooling device 20 of the embodiment, the oil pump 46 is controlled using a state reflecting the degree of background noise of the vehicle speed V, the operating state of the engine 22, and the driving state of the cooling fan 38. One or two of them may be omitted, or a microphone may be installed in the passenger compartment, and noise may be directly detected by this microphone and used for controlling the oil pump 46.

  In the motor cooling device 20 of the embodiment, the oil pump 46 is always turned off when both the motor temperatures Tm1 and Tm2 are less than the threshold T2, but the vehicle speed V, the operating state of the engine 22, the cooling fan 38 The oil pump 46 may be turned on depending on the level of background noise such as a driving state.

  In the motor cooling device 20 of the embodiment, the motors MG1 and MG2 are arranged at positions where cooling by running wind can be expected, but the motors MG1 and MG2 are not necessarily arranged at positions where cooling by running wind can be expected. Also good. In this case, the map illustrated in FIG. 4 can be used in place of FIG. 3 in the process of step S140 of the cooling process routine.

  In the motor cooling device 20 of the embodiment, the oil pump 46 is controlled to be turned on and off based on the motor temperatures Tm1, Tm2, the vehicle speed V, and the like. However, based on the motor temperatures Tm1, Tm2, the vehicle speed V, and the like. It is good also as what changes the rotation speed of an oil pump. In this case, it is desirable to control the oil pump so that it is driven at a higher rotational speed as the motor temperatures Tm1 and Tm2 are larger and the noise level associated with traveling is larger.

  In the embodiment, the cooling device that cools the motor MG1 and the motor MG2 in the hybrid vehicle 10 including the engine 12, the planetary gear mechanism 16, the motor MG1, and the motor MG2 has been described. However, the cooling device is mounted on the vehicle and outputs driving power. As long as it cools the motor or generator that is driven when the motor is driven, it may be a cooling device that cools the motor or generator used in any configuration. For example, a cooling device that cools the traveling motor MG illustrated in the automobile 10B of the modification illustrated in FIG. 5, that is, an oil cooler 44B disposed in front of the vehicle, and an electric cooling fan 38B that blows air to the oil cooler 44B. And a cooling circulation system 40B for the motor comprising an oil circulation path 42B that circulates oil between the oil cooler 44B and the motor MG, and an oil pump 46B that pumps oil from the motor MG to the oil cooler 44B side. It does not matter as a device. In this case, step S150 in the cooling processing routine of FIG. 2 can be omitted.

  Moreover, although the embodiment has been described as a cooling device that cools the motor MG1 and the motor MG2 included in the hybrid vehicle 10, the control method of the cooling device that cools the motor MG1 and the motor MG2 included in the hybrid vehicle 10 is also described. I do not care.

  Here, the correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the motor MG1 and the motor MG2 correspond to “electric motors”, the oil cooler 44 corresponds to “heat exchange means”, the oil pump 46 corresponds to “pressure feeding means”, and the temperature sensors 60 and 62 are “temperature”. The vehicle speed sensor 88, the engine ECU 14 that determines the operating state of the engine 22 and the driving state of the cooling fan 38, and the like correspond to the “noise reflection state detecting means”, and the motor temperatures Tm1, Tm2, the vehicle speed V, and the like. Masks the driving sound of the oil pump 46 with these background noises based on whether the oil pump 46 is in the region to be driven, whether the engine 22 is in operation, and whether the cooling fan 38 is in operation. The hybrid electronic control unit 50 that controls the oil pump 46 to be driven in a ready state corresponds to the “control means”. Here, the “internal combustion engine” may be any type of internal combustion engine such as an engine that outputs power using a hydrocarbon fuel such as gasoline or light oil, or a hydrogen engine. As the “motor”, any motor such as a synchronous motor or an induction motor that is mounted on a vehicle and is driven when driving power is output may be used. The “noise reflection state detection means” is not limited to detecting the driving state of the vehicle speed sensor 88 and the engine 22 and the driving state of the cooling fan 38, but detects a state reflecting the degree of noise based on running. Anything can be used. The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. It is an example for specifically explaining the best mode for doing so, and does not limit the elements of the invention described in the column of means for solving the problem. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It is only a specific example.

  The best mode for carrying out the present invention has been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the gist of the present invention. Of course, it can be implemented in the form.

  The present invention can be used in the manufacturing industry of motor cooling devices.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 10 equipped with a motor cooling device as an embodiment of the present invention. 3 is a flowchart showing an example of a cooling processing routine executed by the hybrid electronic control unit 50. 6 is a map showing an example of the relationship among motor temperatures Tm1, Tm2, vehicle speed V, and driving state of an oil pump 46. It is a map which shows an example of the relationship between the motor temperature Tm1, Tm2, the vehicle speed V, and the drive state of the oil pump 46 of a modification. It is a block diagram which shows the outline of a structure of the motor vehicle 10B carrying the cooling device of a modification.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Hybrid vehicle, 10B motor vehicle, 12 engine, 14 Engine electronic control unit (engine ECU), 16 Planetary gear mechanism, 20 Motor electronic control unit (motor ECU), 21, 22 Inverter 24 Battery, 30 Engine cooling circulation system , 32 Cooling water circulation path, 34 Radiator, 36 Cooling water pump, 38, 38B Cooling fan, 40, 40B Motor cooling circulation system, 42, 42B Oil circulation path, 44, 44B Oil cooler, 46, 46B Oil pump, 50 Hybrid Electronic control unit, 52 CPU, 54 ROM, 56 RAM, 60, 62 Temperature sensor, 64 Outside air temperature sensor, 71 Shift lever, 72 Shift position sensor, 73 Accel pedal, 74 Accel pedal position sensor , 75 brake pedal, 76 a brake pedal position sensor, 78 vehicle speed sensor.

Claims (7)

A cooling device that cools an electric motor that is mounted on a vehicle and that is driven when driving power is output using cooling oil,
Heat exchange means for cooling the cooling oil by heat exchange with outside air;
A pumping means provided in a cooling oil circulation path including the electric motor and the heat exchange means, and circulating the cooling oil in the circulation path by pumping the cooling oil;
Temperature detecting means for detecting the temperature of the electric motor;
Noise reflection state detection means for detecting a noise reflection state as a state reflecting the degree of noise based on running;
Cooling means comprising: control means for controlling the pumping means so that the electric motor is cooled in a state in which the noise based on running becomes a predetermined level or higher based on the detected temperature of the electric motor and the detected noise reflection state. apparatus.   The cooling device according to claim 1, wherein the noise reflection state detection means is means for detecting a vehicle speed. The cooling device according to claim 1 or 2, wherein the cooling device is mounted on a vehicle including an internal combustion engine.
The noise reflection state detecting means is means for detecting an operating state of the internal combustion engine. The cooling device according to any one of claims 1 to 3,
Air blowing means for blowing air toward the heat exchange means,
The noise reflection state detecting means is means for detecting a driving state of the air blowing means. The cooling device according to any one of claims 1 to 4,
The electric motor is arranged such that the electric motor is cooled by running wind,
The control means is means for controlling the pressure feeding means such that when the vehicle speed is equal to or higher than a predetermined vehicle speed, the pressure feeding means is less likely to be driven with respect to the detected motor temperature as the vehicle speed increases.   6. The control unit according to claim 1, wherein the control unit is a unit configured to control the pumping unit to be driven regardless of the detected noise reflection state when the detected temperature of the electric motor is equal to or higher than a predetermined temperature. Cooling system. A heat exchange means for cooling the cooling oil by heat exchange with the outside air, and a cooling oil circulation passage including an electric motor and the heat exchange means. The cooling oil is pumped to supply the cooling oil to the circulation passage. A control method of a cooling device comprising pressure feeding means for circulation in the interior,
Controlling the pumping means so that the motor is cooled in a state in which the noise based on traveling is equal to or higher than a predetermined level based on the temperature of the motor and a noise reflection state as a state reflecting the degree of noise based on traveling. A control method for a cooling device.

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