JP5985844B2 - Vehicle control system - Google Patents

Description

  The present invention relates to a vehicle control system, and more particularly to a vehicle control system capable of cooling a rotating electrical machine with an electric refrigerant pump.

  Vehicles equipped with an engine and a rotating electrical machine are driven by a battery, etc., even when the engine is stopped, in addition to a mechanical oil pump driven by the engine in order to cool the rotating electrical machine, automatic transmission, etc. An oil pump called an electric type or an electric type is used.

  For example, Patent Document 1 describes that, for a vehicle including an electric oil pump in addition to a mechanical oil pump, the automatic stop of the engine is controlled according to the driving state of the electric oil pump. . Here, when the actual number of revolutions of the motor of the electric oil pump exceeds the predetermined upper limit value or falls below the predetermined lower limit value, the hydraulic pressure required during automatic engine stop is supplied by the electric oil pump. It is disclosed that the automatic stop of the engine is prohibited by determining that it is not possible.

  Patent Document 2 describes that, for an oil pump unit including a mechanical oil pump and an electric oil pump, the total required oil supply amount is calculated based on the vehicle speed and the required torque. Furthermore, since the leak amount increases as the oil temperature and hydraulic pressure of the mechanical oil pump increases, it is stated that the discharge amount of the electric oil pump is calculated by correcting the leak amount.

JP 2011-106296 A JP 2009-96326 A

  In the traveling state of the vehicle, for example, the vehicle may not move even if the accelerator is stepped on a slope. Such a state is called an accelerator hold state. When the vehicle is driven by a three-phase synchronous rotating electric machine, the rotating electric machine does not rotate in the accelerator hold state even though a torque command is issued to the rotating electric machine. At this time, the output of the rotating electrical machine and the load are balanced, and current concentrates only on a specific phase among the three phases, and the temperature of the rotating electrical machine rises.

  Therefore, when the rotating electrical machine does not rotate and the temperature of the rotating electrical machine rises, it is determined that the accelerator is in the hold state, and based on the determination, the cooling oil pump is operated and the refrigerant is supplied to the rotating electrical machine. The rotating electric machine can be cooled.

  Here, the temperature increase in a specific phase of the rotating electrical machine may be local, and the temperature sensor that detects the temperature of the rotating electrical machine may cause inaccurate detection.

  The objective of this invention is providing the vehicle control system which can cool a rotary electric machine exactly at the time of an accelerator hold.

A vehicle control system according to the present invention includes a power unit including a rotating electric machine, a refrigerant pump that circulates a refrigerant that cools the rotating electric machine, and a control device that controls the operation of the refrigerant pump. The control device ( when the temperature of the rotating electrical machine is equal to or higher than a predetermined threshold temperature ) AND ( the rotational speed of the rotating electrical machine is low at a predetermined threshold value even though the accelerator depression degree of the vehicle is a predetermined magnitude ) when aND satisfies the condition that the accelerator hold state) below numbers, the coolant pump by startup to supply a predetermined amount of the refrigerant to the rotating electrical machine to drive stop coolant pump when not satisfied aND condition Then, control is performed so that the refrigerant is not supplied to the rotating electrical machine .

Further, in the vehicle control system according to the present invention, when the refrigerant pump has already been started, the control device ( the temperature of the rotating electrical machine is equal to or higher than a predetermined threshold temperature ) AND ( the accelerator depression degree of the vehicle has a predetermined magnitude) However, when the AND condition of the accelerator hold state where the rotational speed of the rotating electrical machine falls below a predetermined low threshold rotational speed ) is satisfied , the rotation speed is higher than the refrigerant supply amount when the AND condition is not satisfied. It is preferable to perform control to increase the amount of refrigerant supplied from the refrigerant pump to the electric machine.

With the above configuration, when the refrigerant pump is stopped , the vehicle control system is configured such that the control device ( the temperature of the rotating electrical machine is equal to or higher than a predetermined threshold temperature ) AND ( the accelerator depression degree of the vehicle is a predetermined magnitude ). when aND conditions are satisfied for also the rotational speed of the rotary electric machine regardless is accelerator hold state below a predetermined threshold low speed), the supply of a predetermined amount of the refrigerant to the rotating electrical machine by startup coolant pump When the AND condition is not satisfied, the refrigerant pump is stopped and control is performed so that the refrigerant is not supplied to the rotating electrical machine . It this way, not only temperature of the determination of the rotating electrical machine, an accelerator pedal pressing degree of the vehicle is in a state below the threshold low rotational speed rotational speed is predetermined for a given magnitude is despite rotating electrical machine since addition of the determination, as compared with the case of determining with only temperature can accurately determine the state of the temperature of the rotating electric machine a accelerator hold is increased. And since a refrigerant | coolant is supplied to the rotary electric machine from a refrigerant | coolant pump based on the exact judgment, the cooling of the rotary electric machine at the time of an accelerator hold can be made appropriate.

Further, in the vehicle control system, when the refrigerant pump has already been activated, the control device ( AND of the rotating electric machine is equal to or higher than a predetermined threshold temperature ) AND ( the accelerator depression degree of the vehicle is a predetermined magnitude ). when aND satisfies the condition that the accelerator hold state) is below the threshold low rotational speed rotational speed is predetermined for the rotary electric machine regardless, coolant pump for rotary electric machine than the supply amount of the refrigerant when not satisfied aND condition Increase the supply of refrigerant from Thus, the rotating electrical machine can be appropriately cooled during the accelerator hold.

It is a figure which shows the structure of the vehicle control system in embodiment which concerns on this invention. In embodiment which concerns on this invention, it is a figure which shows the relationship between an accelerator hold state and the refrigerant | coolant supply state of an electric oil pump. In the embodiment according to the present invention, showing a state of performing a determination of the accelerator hold state, the control of the coolant supply state of the electric oil pump based on the Der Rukoto temperature above the threshold temperature of the rotating electric machine. In the embodiment according to the present invention, showing a state of performing a determination of the accelerator hold state, the control of the coolant supply state of the electric oil pump based on the Der Rukoto torque is greater than or equal to the threshold torque of the rotary electric machine.

  Embodiments according to the present invention will be described below in detail with reference to the drawings. In the following, a hybrid vehicle on which an engine and a rotating electrical machine are mounted will be described as a vehicle. However, this is an example for explanation, and any vehicle including a rotating electrical machine may be used. For example, an electric vehicle without an engine may be used. Moreover, although the structure which has an engine, one rotary electric machine, and the power transmission mechanism provided between it as a power supply device of a hybrid vehicle is demonstrated, this is also the illustration for description. Here, the hybrid vehicle only needs to have an engine and a rotating electrical machine, and the relationship between the output of the engine and the output of the rotating electrical machine can be appropriately changed according to the specifications of the vehicle. Moreover, although the description will be given assuming that the rotating electrical machine mounted on the vehicle is one, this is also an example, and a plurality of rotating electrical machines may be mounted on the vehicle. For example, one rotating electric machine may be used for driving, and the other rotating electric machine may be used for power generation, or separate rotating electric machines may be used for front wheel driving and rear wheel driving.

  In the following, ATF, which is also used as a lubricating oil as a refrigerant for cooling a rotating electrical machine, will be described, but this is an example, and other cooling fluids may be used. Accordingly, the notation of an oil pump is used for the refrigerant pump that circulates the refrigerant, and this is also adapted to the case where ATF is used.

  The power supply for the drive circuit of the electric oil pump will be described as a low voltage power supply independent of the power supply device for the rotating electrical machine, but this is an illustrative example. For example, electric power converted into a low voltage from a power supply device of a rotating electrical machine may be supplied to a drive circuit of an electric oil pump.

  In the following description, it is assumed that the rotating electrical machine and the power transmission mechanism are housed in one case body, and the refrigerant circulates between the case and the oil pump unit. However, this is an illustrative example. is there. For example, it is good also as a structure which a refrigerant | coolant circulates between a rotary electric machine, a power transmission mechanism, and an oil pump unit, without putting together in one case.

  Below, the same code | symbol is attached | subjected to the same element in all the drawings, and the overlapping description is abbreviate | omitted. In the description in the text, the symbols described before are used as necessary.

  FIG. 1 is a diagram showing a configuration of a vehicle control system 10 for a hybrid vehicle. This vehicle control system 10 is a system including a cooling structure 12 for a rotating electrical machine 20 mounted on a hybrid vehicle and a control device 80.

  The cooling structure 12 includes an engine 16 and a rotating electric machine 20 shown as M / G in FIG. 1 as a power unit 14 that is a driving source of the hybrid vehicle, and an M / G driving circuit 30 connected to the rotating electric machine 20 and its A high voltage power supply 32 that is a power supply is included. The cooling structure 12 further includes an oil pump unit 40 that circulates and supplies the refrigerant 26 into the case body 24 that includes the rotating electrical machine 20. The oil pump unit 40 includes a mechanical oil pump 42 shown as MOP in FIG. 1 and an electric oil pump 44 shown as EOP.

  The power unit 14 includes an engine 16, a rotating electrical machine 20, and a power transmission mechanism 18 provided therebetween. The engine 16 is an internal combustion engine. The rotating electrical machine 20 is a motor / generator (M / G) mounted on the hybrid vehicle, and functions as a motor when electric power is supplied from the M / G drive circuit 30, and when driven by the engine 16, Alternatively, it is a three-phase synchronous rotating electric machine that functions as a generator during braking of a hybrid vehicle.

The temperature detector 27 provided in the rotating electrical machine 20 is rotating electrical machine temperature detection means for detecting the temperature θ _M of the rotating electrical machine 20. The detection data of the temperature detector 27 is transmitted to the control device 80 using an appropriate signal line (not shown).

  The power transmission mechanism 18 is a mechanism having a function of distributing the power supplied to the hybrid vehicle between the output of the engine 16 and the output of the rotating electrical machine 20. As the power transmission mechanism 18, a planetary gear mechanism connected to three shafts, that is, an output shaft of the engine 16, an output shaft of the rotating electrical machine 20, and an output shaft to an axle (not shown) can be used. In FIG. 1, the shaft connecting the power transmission mechanism 18 and the engine 16 is the output shaft 22 of the engine 16. The output shaft 22 is connected to the drive shaft of the mechanical oil pump 42 via the connection shaft 70 and is used to drive the mechanical oil pump 42.

  The M / G drive circuit 30 is a circuit including an inverter that performs power conversion between the DC power of the high-voltage power supply 32 and the AC power for driving the rotating electrical machine 20. The inverter is a circuit that generates a three-phase drive signal by PWM (Pulse Width Modulation) control that appropriately adjusts on / off timings of a plurality of switching elements, and supplies the three-phase drive signal to the rotating electrical machine 20. The PWM control is a control for modulating the pulse width by comparing a fundamental wave signal having a period corresponding to the rotation period of the rotating electrical machine 20 and a carrier signal having a sawtooth waveform. The inverter brings the output of the rotating electrical machine 20 into a desired operation state by this PWM control.

  The high voltage power source 32 is a chargeable / dischargeable high voltage secondary battery. Specifically, it can be composed of a lithium ion assembled battery having a terminal voltage of about 200V to about 300V. The assembled battery is obtained by combining a plurality of batteries each having a terminal voltage of 1 V to several V, called a single battery or a battery cell, to obtain the predetermined terminal voltage. As the high voltage power supply 32, a nickel-metal hydride battery, a large capacity capacitor, or the like can be used.

  The case body 24 is a housing that includes the power transmission mechanism 18 and the rotating electrical machine 20 inside. The interior space of the case body 24 stores a coolant 26 for lubricating the movable parts of the power transmission mechanism 18 and the rotating electrical machine 20 and cooling the power transmission mechanism 18 and the rotating electrical machine 20. As the refrigerant, a lubricating oil called ATF can be used.

The temperature detector 28 provided in the case body 24 is a refrigerant temperature detection unit that detects the temperature θ _{C of the} refrigerant 26. The detection data of the temperature detector 28 is transmitted to the control device 80 using an appropriate signal line (not shown).

  The oil pump unit 40 is a unit including a mechanical oil pump 42 and an electric oil pump 44, and is a refrigerant pump unit that circulates and supplies the refrigerant 26 to the internal space of the case body 24. The refrigerant discharge path 60 is a refrigerant distribution pipe that connects the oil pump unit 40 and a refrigerant discharge port provided on the lower side of the case body 24 along the direction of gravity, that is, at a location near the bottom of the case body 24. The refrigerant supply path 62 is a refrigerant distribution pipe that connects the oil pump unit 40 and an upper side of the case body 24 along the direction of gravity, that is, a refrigerant supply port provided at a location near the ceiling of the case body 24. The oil cooler 50 is a heat exchanger that reduces the temperature of the refrigerant 26 by air cooling or water cooling.

  The mechanical oil pump 42 is a mechanical refrigerant pump whose drive shaft is connected to the output shaft 22 of the engine 16 via the connection shaft 70 and is driven when the engine 16 operates. In other words, the mechanical oil pump 42 starts to be driven as the engine 16 is started, and when the engine 16 is stopped, the driving of the mechanical oil pump 42 is ended.

  The electric oil pump 44 is an electric refrigerant pump that is driven by the EOP drive circuit 72 under a control signal from the control device 80. The EOP drive circuit 72 is supplied with DC power from a low voltage power supply 74. The low voltage means a low voltage compared to the voltage of the high voltage power supply 32. For example, a voltage of about 12V to 16V can be used. As a motor for rotating the drive shaft of the electric oil pump 44, a three-phase synchronous motor can be used. In this case, the EOP drive circuit 72 includes an inverter having a DC / AC conversion function. Moreover, the output of the electric oil pump 44 can be varied by changing the on / off duty in the PWM control of the inverter.

  A single-phase AC motor can be used instead of the three-phase synchronous motor, or a DC motor can be used. The content of the EOP drive circuit 72 is changed according to the motor type used as a motor for rotating the drive shaft of the electric oil pump 44.

  The mechanical oil pump 42 and the electric oil pump 44 are connected in parallel with each other between the refrigerant discharge path 60 and the refrigerant supply path 62. The check valve 46 is a valve provided so that the refrigerant 26 does not flow back between the mechanical oil pump 42 and the refrigerant supply port of the case body 24. Similarly, the check valve 48 is a valve provided so that the refrigerant 26 does not flow backward between the electric oil pump 44 and the refrigerant supply port of the case body 24.

  The control device 80 has a function of controlling each of the above-described elements as a whole. In particular, the control device 80 has a function of effectively cooling the rotating electrical machine 20 in the accelerator hold state. Such a control device 80 can be configured by a computer suitable for mounting on a hybrid vehicle.

  The accelerator depression degree detection unit 90 connected to the control device 80 is a unit that is attached to the accelerator of the hybrid vehicle and detects the state of the accelerator that is stepped on by a user such as a driver.

The control device 80 determines that the accelerator is in the accelerator hold state when the rotational speed of the rotating electrical machine falls below a predetermined threshold low rotational speed even though the accelerator depression degree of the vehicle is a predetermined magnitude. Unit 82, rotating electric machine state determination unit 84 for determining whether the temperature of rotating electric machine 20 is equal to or higher than a predetermined threshold temperature, or whether the output torque of rotating electric machine 20 is equal to or higher than a predetermined threshold torque, and electric oil An EOP operation control unit 86 that controls the operation of the pump 44 is included. These functions can be realized by executing software. Specifically, it can be realized by executing an EOP control program.

  The operation of the above configuration will be described in detail with reference to FIG. FIG. 2 is a diagram for explaining the determination of the accelerator hold state and the control of the refrigerant supply state of the electric oil pump 44 associated therewith. In each of FIGS. 2A to 2D, the horizontal axis represents time.

The vertical axis in FIG. 2 (a) is the accelerator depression degree. Here, normalization is performed, where 0 is a state where the accelerator is not depressed at all, and 100 is a state where the accelerator is fully depressed. The control device 80 acquires the magnitude of the accelerator depression degree based on the data detected by the accelerator depression degree detection unit 90. FIG. 2 shows that the accelerator was not stepped on by the user until time t ₁ , and the accelerator was stepped on by the user from time t ₁ to reach the limit. That is, the user has fully depressed the accelerator from time t _{1 in an} attempt to accelerate the hybrid vehicle.

The vertical axis in FIG. 2B is the rotational speed of the rotating electrical machine 20. FIG. 2B shows a state in which the rotational speed of the rotating electrical machine 20 is gradually decreasing before the time t ₁ . Now, assuming that the hybrid vehicle travels only with the rotating electric machine, the vehicle speed gradually decreases. At this time, it can be considered that the vehicle speed is decelerated due to road resistance because the accelerator is not stepped on as shown in FIG. For example, when the hybrid vehicle is climbing uphill. Therefore, the user depresses the accelerator at time t ₁ in an attempt to stop the deceleration.

However, FIG. 2 (b) shows that the rotational speed of the rotating electrical machine 20 is further lowered and the hybrid vehicle is almost in a stopped state despite the accelerator being depressed. Assuming that the rotation speed of the rotating electrical machine 20 when the axle is hardly rotating is the threshold low rotation speed N ₀ , the rotating electrical machine 20 has a low threshold rotation speed at the time t ₂ even though the accelerator is depressed. Below N ₀ . Thus, a phenomenon called accelerator hold is that the rotational speed of the rotating electrical machine falls below a predetermined threshold low rotational speed even though the accelerator depression degree of the vehicle is a predetermined magnitude.

  The accelerator hold is generated by balancing the load received by the vehicle from the road surface and the torque output from the vehicle power unit. An example of such a state is when the vehicle is on an uphill. The accelerator hold state is also entered when the rotation of the rotating electrical machine 20 is in a locked state for other reasons.

  In the accelerator hold state, the rotation of the rotating electrical machine 20 is almost stopped, so that the switching of the phases of the three-phase drive signal becomes slow and almost fixed to a specific phase. Thus, when it becomes a fixed state in a specific phase, only the specific switching element of an inverter will be set to ON, and an electric current will concentrate on the coil of a specific phase. As a result, the temperature of the rotating electrical machine 20 is locally increased. Therefore, it is necessary to accurately detect the accelerator hold state and quickly cool the rotating electrical machine 20.

In the accelerator hold state, as shown in FIGS. 2A and 2B, the accelerator depression degree is not less than a predetermined magnitude, and the rotation speed of the rotating electrical machine 20 is not more than the threshold low rotation speed N _0. Can be judged. The control device 80 compares the accelerator depression data transmitted from the accelerator depression detector 90 with a predetermined threshold value, and compares the rotation speed of the rotating electrical machine 20 with the threshold low rotation speed N _0. It can be determined whether or not the hold state. That is, the accelerator pedal pressing degree data is equal to or greater than the predetermined threshold value, and when the rotational speed of the rotary electric machine 20 is below the threshold low rotational speed N _0, is determined to be the accelerator hold state. The accelerator hold state determination unit 82 of the control device 80 executes such a determination process, and when determining that it is in the accelerator hold state, can output the accelerator hold signal from the OFF state to the ON state.

FIG. 2C shows the state of the accelerator hold signal output from the control device 80 on the vertical axis. The accelerator hold signal can be set to ON state = High when in the accelerator hold state, and OFF state = Low when not in the accelerator hold state. As shown in FIG. 2 (a), the accelerator pedal pressing degree, since it maintains its state reached the limit up from the time t _1, the time t ₂ later is maintained over a predetermined threshold value Shall. At that time, the accelerator hold state is when the rotational speed of the rotating electrical machine 20 is equal to or lower than the threshold low rotational speed. FIG from 2 (b), when the rotational speed of the rotary electric machine 20 is below the threshold low engine speed is between the time t ₂ of time t _3. Accordingly, as shown in FIG. 2 (c), the accelerator hold signal, ON changed from OFF at time t _2, the OFF from ON at time t _3.

  FIG. 2D shows the refrigerant supply state by the electric oil pump 44 on the vertical axis. When the accelerator hold state is entered, the rotating electrical machine 20 causes a local temperature rise, and therefore it is necessary to supply the refrigerant 26 to the rotating electrical machine 20 by the electric oil pump 44. Accordingly, when the electric oil pump 44 is stopped, the control device 80 instructs the EOP drive circuit 72 to start the electric oil pump 44 based on the accelerator hold signal. As a result, the electric oil pump 44 starts to operate and supplies a predetermined flow rate of the refrigerant 26 to the rotating electrical machine 20.

Thus, at time t ₂ the accelerator hold signal is turned ON from OFF, the electric oil pump 44 to the operative state from the stopped state, the operating state of the electric oil pump 44 at time t ₃ when the accelerator hold state returns from ON to OFF Return to the stopped state. In terms of the coolant supply state, at time t _2, the A = flow rate 0, B = are changed to a predetermined flow rate. At time t ₃ , A = flow rate 0 again. By doing so, the refrigerant 26 can be supplied from the electric oil pump 44 to the rotating electrical machine 20 when the accelerator is held. Such processing is executed by the function of the EOP operation control unit 86 of the control device 80.

In the above and at time t ₂ before the electric oil pump 44 is stopped. Here, the EOP drive circuit 72 can vary the flow rate and the like by changing the on / off duty when the electric oil pump 44 is in an operating state by PWM control. Therefore, if the electric oil pump 44 is already operating before the time t ₂ and the on / off duty is set to a small value, the on / off duty can be increased at the time t ₂ to increase the flow rate. .

In terms of FIG. 2 (d), the at the time t ₂ not previously accelerator hold state and time t ₃ after, and A = flow rate Q _1, the between time t ₂ is the accelerator hold state time t _3, B = a predetermined possible to the flow rate Q _2. Here, the predetermined flow rate Q ₂ is a flow rate larger than the flow rate Q ₁ . By doing so, more refrigerant can be supplied from the electric oil pump 44 to the rotating electrical machine 20 when the accelerator hold state is set, compared to when the accelerator hold state is not set. Such processing is also executed by the function of the EOP operation control unit 86 of the control device 80.

In the above description, the refrigerant supply state of the electric oil pump 44 is controlled in accordance with ON / OFF of the accelerator hold signal. This can be further related to the temperature θ _{M of the} rotating electrical machine 20 or the torque T _{M of the} rotating electrical machine 20.

FIG. 3 is a diagram for explaining how the refrigerant supply state of the electric oil pump 44 is controlled based on the accelerator hold signal and the temperature θ _{M of the} rotating electrical machine. The horizontal axis in FIGS. 3A and 3B is time. In FIG. 3B, the accelerator hold signal described in FIG. 2 is plotted on the vertical axis. Here, as in FIG. 2, the accelerator hold signal changes from OFF to ON at time t ₂ and returns from ON to OFF again at time t ₃ .

The vertical axis in FIG. 3A is the temperature θ _M of the rotating electrical machine 20. Although the temperature θ _M of the rotating electrical machine 20 does not necessarily detect a locally rising temperature based on the accelerator hold state depending on the mounting position of the temperature sensor, it can be evaluated as indicating the representative temperature of the rotating electrical machine 20. For example, when the temperature θ _M of the rotating electrical machine 20 is equal to or higher than a predetermined threshold temperature θ _M0, it can be determined that the refrigerant 26 needs to be supplied to the rotating electrical machine 20. The determination as to whether or not the temperature θ _M of the rotating electrical machine 20 is equal to or higher than the threshold temperature θ _M is performed by the function of the rotating electrical machine state determining unit 84 of the control device 80 based on the detection value data of the temperature detector 27.

FIG. 3A shows that the temperature θ _M of the rotating electrical machine 20 becomes equal to or higher than the threshold temperature θ _M0 at the time t ₄ and returns again below the threshold temperature θ _M0 at the time t ₅ . If the operating period of the electric oil pump 44 is determined only by the temperature θ _M of the rotating electrical machine 20 as in the prior art, the electric oil pump 44 is operated between time t ₄ and time t ₅ . In this case, as shown in FIG. 3B, the accelerator hold state is between time t ₂ and time t ₃ , so between time t ₄ and time t ₂ , and time t ₃ between the time t ₅ will be no need for the operation of the electric oil pump 44 that corresponds to the accelerator hold state.

Therefore, if the operating condition of the electric oil pump 44 is (acceler hold state) AND (the temperature θ _M of the rotating electrical machine 20 is equal to or higher than the threshold temperature θ _M0 ), the temperature θ _M of the rotating electrical machine 20 is It can be used for both monitoring and accelerator hold monitoring. In the example of FIG. 3 (a), the AND condition is satisfied period is between the time t ₂ of time t _3. Therefore, in FIG. 3 (a), as a coolant supply state of the EOP, the a time t ₃ subsequent to the time t ₂ to the coolant supply state A = flow rate 0, the refrigerant supply state between the time t ₂ of time t ₃ It is shown that B = predetermined flow rate. By doing in this way, with respect to the rotary electric machine 20 which became the accelerator hold state, a refrigerant | coolant can be supplied appropriately, without carrying out excessive operation of the electric oil pump 44, without carrying out overcooling.

Further, when the electric oil pump 44 can change the flow rate by PWM control, when the temperature θ _M of the rotating electrical machine 20 becomes equal to or higher than the threshold temperature θ _M0 , the refrigerant supply state is set to A = flow rate Q ₁ , (Being in the accelerator hold state) When the AND (the temperature θ _M of the rotating electrical machine 20 is equal to or higher than the threshold temperature θ _M0 ) is satisfied, the refrigerant supply state can be set to B = predetermined flow rate Q ₂ . Here, the flow rate Q ₁ is a flow rate required when the rotating electrical machine 20 becomes the threshold temperature θ _M0 or more in a normal use state, and the predetermined flow rate Q ₂ is larger than the flow rate Q ₁ and is locally in the accelerator hold state. By setting the flow rate to be suitable for a sudden and rapid temperature rise, it is possible to appropriately deal with an accelerator hold state when the temperature of the rotating electrical machine 20 has already risen to some extent.

Note that the operating condition of the electric oil pump 44 can be set to (accelerator hold state) OR (the temperature θ _M of the rotating electrical machine 20 is equal to or higher than the threshold temperature θ _M0 ). In this case, since the operating range of the electric oil pump 44 is widened, the power consumption is increased, but the rotating electrical machine 20 is sufficiently cooled, and overheating can be effectively suppressed.

4, based on the torque T _M of the accelerator hold signal and the rotary electric machine is a diagram for describing a manner of controlling the refrigerant supply state of the electric oil pump 44. FIG. 4B is the same as FIG. 3B and shows the state of the accelerator hold signal. FIGS. 4 (a), except that the vertical axis is the torque T _M of the rotary electric machine 20 is the same as FIG. 3 (a).

When the torque T _M of the rotary electric machine 20 is large, the drive current of the rotary electric machine 20 is large, the heat generation is large and the temperature rise occurs. Therefore, instead of providing the temperature detector 27 to the rotary electric machine 20 can monitor the temperature rise of the rotary electric machine 20 with the magnitude of the torque T _M. The torque T _M of the rotating electrical machine 20 is a substitute characteristic of the temperature of the rotating electrical machine 20 and therefore does not necessarily detect a locally rising temperature based on the accelerator hold state, but indicates a representative temperature of the rotating electrical machine 20. It can be evaluated as a thing. For example, when the torque T _M of the rotating electrical machine 20 is _{equal to} or greater than a predetermined threshold torque T _M0, it can be determined that the refrigerant 26 needs to be supplied to the rotating electrical machine 20. The determination of whether or not the torque T _M of the rotating electrical machine 20 is _{equal to} or greater than the threshold torque T _M0 is performed by the function of the rotating electrical machine state determining unit 84 of the control device 80.

FIG. 4A shows that the torque T _M of the rotating electrical machine 20 becomes equal to or greater than the threshold torque T _M0 at time t ₆ and returns to less than the threshold torque T _M0 again at time t ₇ . Here, when it determines the operation period of the electric oil pump 44 only torque T _M of the rotary electric machine 20, thereby actuating the electric oil pump 44 between the time t ₆ of time t _7. In this case, as shown in FIG. 4B, the accelerator hold state is between time t ₂ and time t ₃ , so between time t ₆ and time t ₂ , and time t ₃ between the time t ₇ would not require the operation of the electric oil pump 44 that corresponds to the accelerator hold state.

Therefore, if the operating condition of the electric oil pump 44 is (accelerator hold state) AND (the torque T _M of the rotating electrical machine 20 is _{equal to} or greater than the threshold torque T _M0 ), the torque T _M of the rotating electrical machine 20 It can be used for both monitoring and accelerator hold monitoring. In the example of FIG. 4 (a), the AND condition is satisfied period is between the time t ₂ of time t _3. Therefore, in FIG. 4 (a), as a coolant supply state of the EOP, the a time t ₃ subsequent to the time t ₂ to the coolant supply state A = flow rate 0, the refrigerant supply state between the time t ₂ of time t ₃ It is shown that B = predetermined flow rate. By doing in this way, with respect to the rotary electric machine 20 which became the accelerator hold state, a refrigerant | coolant can be supplied appropriately, without carrying out excessive operation of the electric oil pump 44, without carrying out overcooling.

Thus, the torque T _M of the rotating electrical machine 20 can be used for appropriate operation control of the electric oil pump 44, similarly to the temperature θ _M of the rotating electrical machine 20 of FIG. As described in relation to FIG. 3, the flow rate A = Q ₁ is required when the rotating electrical machine 20 becomes _{equal to} or higher than the threshold torque T _M0 in the normal use state by using the PWM control of the electric oil pump 44. The flow rate may be a flow rate B = predetermined flow rate Q ₂ which is greater than the flow rate Q ₁ and can cope with a local and rapid temperature increase in the accelerator hold state. Further, the operating condition of the electric oil pump 44 can be set to (accelerator hold state) OR (the torque T _M of the rotating electrical machine 20 is _{equal to} or greater than the threshold torque T _M0 ).

Furthermore, the content described in FIG. 3 and the content described in FIG. 4 can be combined. For example, the operating condition of the electric oil pump 44 is (acceleration hold state) AND [(the temperature θ _M of the rotating electrical machine 20 is greater than or equal to the threshold temperature θ _M0 ) AND (the torque T _{M of the} rotating electrical machine 20 is the threshold torque T _M0 Or the like)]. In this case, it is possible to further prevent the electric rotating machine 20 in the accelerator hold state from being overcooled, further suppress the excessive operation of the electric oil pump 44, and appropriately supply the refrigerant. Further, the operating condition of the electric oil pump 44 is (acceleration hold state) AND [(the temperature θ _M of the rotating electrical machine 20 is greater than or equal to the threshold temperature θ _M0 ) OR (the torque T _{M of the} rotating electrical machine 20 is the threshold torque T _M0 Or the like)].

  The vehicle control system according to the present invention can be used for a vehicle equipped with an electric oil pump.

  DESCRIPTION OF SYMBOLS 10 Vehicle control system, 12 Cooling structure, 14 Power unit, 16 Engine, 18 Power transmission mechanism, 20 Rotating electric machine, 22 Output shaft, 24 Case body, 26 Refrigerant, 27, 28 Temperature detector, 30 M / G drive circuit, 32 High-voltage power supply, 40 Oil pump unit, 42 Mechanical oil pump, 44 Electric oil pump, 46, 48 Check valve, 50 Oil cooler, 60 Refrigerant discharge path, 62 Refrigerant supply path, 70 Connection shaft, 72 EOP drive circuit 74 Low voltage power supply, 80 control device, 82 accelerator hold state determination unit, 84 rotating electrical machine state determination unit, 86 EOP operation control unit, 90 accelerator depression degree detection unit.

Claims (2)

A power unit including a rotating electrical machine;
A refrigerant pump for circulating a refrigerant for cooling the rotating electrical machine;
A control device for controlling the operation of the refrigerant pump;
With
When the refrigerant pump is stopped, the control device
( The temperature of the rotating electrical machine is equal to or higher than a predetermined threshold temperature ) AND (In the accelerator hold state where the rotational speed of the rotating electrical machine is lower than the predetermined threshold low rotational speed even though the accelerator depression degree of the vehicle is a predetermined magnitude ) when lying) aND satisfies the condition, the coolant pump by startup to supply a predetermined amount of the refrigerant to the rotating electrical machine, the refrigerant is supplied to the rotating electrical machine drive stops the coolant pump when not satisfied aND condition The vehicle control system characterized by performing control which does not carry out. The vehicle control system according to claim 1,
When the refrigerant pump is already activated, the control device
( The temperature of the rotating electrical machine is equal to or higher than a predetermined threshold temperature ) AND (In the accelerator hold state where the rotational speed of the rotating electrical machine is lower than the predetermined threshold low rotational speed even though the accelerator depression degree of the vehicle is a predetermined magnitude ) vehicle control system when aND condition is satisfied in lying), and performs control than the supply amount of the refrigerant when not satisfied aND condition increases the supply amount of the refrigerant from the refrigerant pump for rotary electric machine.

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