JP2013199216A - Hydraulic control device of hybrid vehicle - Google Patents

Abstract

The hydraulic pressure of a hybrid vehicle can cool a motor / generator that outputs power for driving the vehicle and can reduce drag loss of a member that rotates following the rotation of the motor / generator. A control device is provided.
A cooling oil passage 22 communicating with each motor / generator 2, a lubricating oil passage 18 for supplying oil to a power transmission portion in a power split device 7, and cooling by being driven by the power of an internal combustion engine. A first oil pump 14 communicating with the oil passage 22 and the lubricating oil passage 18; a second oil pump 15 driven by the power of the electric motor and communicating with the cooling oil passage 22 and the lubricating oil passage 18; A first switching valve 26 that selectively switches the oil passage to which the oil output from the oil pump 15 is supplied to the cooling oil passage 22 and the lubricating oil passage 18 is provided.
[Selection] Figure 1

Description

  The present invention relates to a hydraulic control device for a hybrid vehicle that supplies oil to a heat generating portion and a sliding portion by an oil pump driven by an internal combustion engine and an oil pump driven by an electric motor.

  A hybrid vehicle is known in which a power transmission device that transmits power output from an internal combustion engine to an output member includes a motor / generator having a power generation function and an electric function. A motor / generator mounted on a hybrid vehicle generates heat due to electrical resistance, etc., when it functions as a generator or as a motor, and the output torque of the motor / generator decreases due to the heat. There is a possibility that. Therefore, conventionally known hybrid vehicles are configured to supply oil to the motor / generator for cooling. Further, since the gear train portion and the like in the power transmission device are in frictional contact, oil is supplied to the friction contact portion to improve lubricity, thereby improving power transmission efficiency.

  As means for supplying oil to the motor / generator, gear train, etc., there was a mechanical oil pump such as an oil pump driven by the power output from the internal combustion engine, an oil pump connected to an output member, or a dedicated electric motor. An electric oil pump or a pump that pumps up stored oil to an output member is known.

  On the other hand, the hybrid vehicle uses an HV traveling mode in which the vehicle travels using the power output from the internal combustion engine and the power of the motor / generator, the EV traveling mode in which the vehicle travels with the internal combustion engine stopped, or the power output from the internal combustion engine. Various operation modes such as a power generation mode in which power is generated and stopped by a generator can be selected. For this reason, if a large amount of oil is supplied when the torque for transmitting power and the rotational speed are low, the power loss increases due to oil agitation loss, etc., or an oil pump is used to output excessively supplied oil. The driving frequency may increase, and the fuel consumption may decrease.

  Therefore, Patent Document 1 describes a device that can suppress excessive oil supply depending on the travel mode of the hybrid vehicle. A hybrid vehicle described in Patent Document 1 includes a planetary gear mechanism coupled to an internal combustion engine and a first motor / generator, and a second motor / generator coupled to an output element of the planetary gear mechanism via a speed reduction mechanism. And a first oil pump driven by power output from the internal combustion engine, and a second oil pump coupled to the output member. The first oil pump is configured to supply oil to the planetary gear mechanism and the first motor / generator, and the second oil pump is configured to supply oil to the speed reduction mechanism and the second motor / generator. It is configured.

  In the hybrid vehicle configured as described above, in order to stop the internal combustion engine at 0 (zero) in the EV traveling mode, the first motor / generator is rotated so as to have a rotational speed corresponding to the vehicle speed. It is done. In the EV traveling mode, the torque transmitted to the planetary gear mechanism is smaller than that in the HV traveling mode, and therefore the amount of oil supplied to the planetary gear mechanism may be small. For this reason, in Patent Document 1, the oil discharged from the second oil pump is reduced through a check valve in addition to the speed reduction mechanism and the second motor / generator to the planetary gear mechanism and the first motor / generator. It is configured to supply.

  Patent Document 2 describes a hydraulic control device that can prevent seizure due to a temperature rise in the gear train portion and suppress agitation loss due to the gear train portion scooping up oil. The hydraulic control device described in Patent Document 2 is configured to scoop up stored oil by an output gear, and temporarily store the scooped up oil in a catch tank. The oil is supplied to the lubrication part or the cooling part via the oil passage. In addition, an opening / closing valve is provided in the oil passage, and when the temperature of the cooling unit is high, the opening / closing valve is opened to supply oil from the catch tank to the cooling unit.

  Further, Patent Document 3 describes a hydraulic control device configured to supply oil stored in a catch tank to a lubrication unit and a cooling unit via an oil passage, as in Patent Document 2, A control valve that can control the flow rate of the output oil is provided in the oil passage. The control valve supplies a large amount of oil when the torque to be transmitted is large or the speed of the gear is fast, and supplies a small amount of oil when the torque to be transmitted is small or the speed of the gear is slow. By doing so, it is configured to supply an appropriate amount of oil to the lubrication unit and the cooling unit. Also, another oil passage for supplying oil to the motor / generator for traveling is provided with a control valve, and the control valve is output from the control valve according to the time during which the EV traveling mode is set. It is configured to control the flow rate of oil. That is, when the EV traveling mode is set for a long time, the oil flow rate output from the control valve is increased. When the EV traveling mode is set for a short time, the oil flow rate output from the control valve is increased. It is configured to reduce the amount.

  Note that Patent Document 4 discloses a hydraulic control configured to switch which of two motors / generators that sandwich the catch tank to supply more oil according to the amount of oil stored in the catch tank. An apparatus is described.

JP 2010-1206047 A JP 2008-279826 A JP 2006-312353 A JP 2010-242900 A

  The second oil pump described in Patent Document 1 is driven by an output member, and the devices described in Patent Documents 2 to 4 store the oil pumped up by the output gear in a catch tank and store the oil in each member. It is configured to supply. Therefore, even when the vehicle is in the EV travel mode, the oil pump is driven and the output gear scoops up the oil, so there is no power loss due to driving the oil pump or power loss due to the output gear scooping up oil. It may occur unavoidably and fuel consumption may deteriorate.

  Further, the hybrid vehicle described in Patent Document 1 is configured to always supply oil to the planetary gear mechanism and the first motor / generator in the EV traveling mode. On the other hand, in the EV travel mode, a large torque is rarely transmitted to the planetary gear mechanism. Therefore, if oil is constantly supplied to the planetary gear mechanism, the power loss of the oil pump increases as the oil is supplied. End up.

  The present invention has been made against the background described above, and can cool a motor / generator that outputs power for driving a vehicle and can rotate following the rotation of the motor / generator. It is an object of the present invention to provide a hydraulic control device for a hybrid vehicle that can reduce the drag loss.

  In order to achieve the above object, the invention according to claim 1 is connected to a first rotating element to which an internal combustion engine is connected, a second rotating element to which a first motor / generator is connected, and an output member of a vehicle. And a hydraulic control device for a hybrid vehicle having a power split device having a third rotating element connected to a second motor / generator, a cooling oil passage communicating with each motor / generator, and a power split device in the power split device. A lubricating oil passage that supplies oil to the power transmission unit, a first oil pump that is driven by the power of the internal combustion engine, and communicates with the cooling oil passage and the lubricating oil passage, and is driven by the power of another motor. A second oil pump communicating with the cooling oil passage and the lubricating oil passage, and an oil passage supplied with oil output from the second oil pump, the cooling oil passage And it is characterized in that it comprises a first switching valve that switches selectively into the serial lubricating oil passage.

  According to a second aspect of the present invention, in the first aspect of the invention, the first switching valve is configured such that the temperature of the motor / generator that outputs power to drive the vehicle is equal to or higher than a first threshold value. The oil passage through which oil discharged from the second oil pump flows is switched to the cooling oil passage, and the temperature of the motor / generator that outputs power to drive the vehicle is less than a first threshold value and the first When the vehicle travels more than a predetermined distance with the oil pump not being driven, the oil passage through which the oil discharged from the second oil pump flows is switched to the lubricating oil passage side. It is a hydraulic control apparatus of a hybrid vehicle.

  According to a third aspect of the present invention, in the first or second aspect of the invention, the cooling oil passage includes a first oil passage communicating with the first motor / generator and a second oil communicating with the second motor / generator. A hydraulic control device for a hybrid vehicle, further comprising a second switching valve that selectively switches an oil passage through which oil flows to the first oil passage and the second oil passage. is there.

  According to a fourth aspect of the present invention, in the third aspect of the invention, the second switching valve causes the oil to flow when the temperature of one of the motor generators is equal to or higher than a second threshold value. Is switched to an oil passage communicating with the one motor / generator, the temperature of the one motor / generator is lower than a second threshold value, and the temperature of the other motor / generator is equal to or higher than a third threshold value. In this case, the hydraulic control device for a hybrid vehicle is characterized in that the flow path through which the oil flows is switched to an oil path communicating with the other motor / generator.

  According to a fifth aspect of the present invention, in the third or fourth aspect of the present invention, the second switching valve is configured such that when the load acting on the first motor / generator is greater than the load acting on the second motor / generator, When the load acting on the first motor / generator is smaller than the load acting on the second motor / generator, the oil passage through which oil flows is changed to the second oil path. A hydraulic control device for a hybrid vehicle characterized by switching to an oil passage.

  A sixth aspect of the present invention is the hydraulic control apparatus for a hybrid vehicle according to any one of the first to fifth aspects, further comprising an oil cooler for cooling the oil supplied to the cooling oil passage. is there.

  According to the present invention, when the first oil pump driven by the power of the internal combustion engine is not driven, the second oil pump can supply oil to each motor / generator and the power split device. Therefore, even when the vehicle is driven by the power of the motor / generator, each motor / generator can be cooled and the power split device can be lubricated. Further, the oil passage through which the oil flows can be selectively switched by the first switching valve between a cooling oil passage communicating with each motor / generator and a lubricating oil passage communicating with the power split device. Therefore, excessive supply of oil to the power split device can be suppressed or prevented, and the lubricity of the power split can be maintained. That is, an appropriate amount of oil can be supplied to the power split device. Moreover, each motor / generator can be cooled by switching the oil path through which the oil flows by the first switching valve to the cooling oil path, and the temperature of the motor / generator is prevented from excessively rising. Or it can be prevented.

  The first switching valve is switched so as to supply oil to the motor / generator when the temperature of the motor / generator that outputs power to drive the vehicle is high. Therefore, it is possible to suppress or prevent the durability of the motor / generator that outputs motive power to drive the vehicle and the output torque from decreasing. On the other hand, when the vehicle travels a predetermined distance when the temperature of the motor / generator is relatively low and the first oil pump is not driven, oil is supplied to the power transmission unit in the power split device. The switching valve is switched as follows. Therefore, drag loss of a member that rotates following the rotation of the motor / generator can be reduced, and stirring loss caused by excessive supply of oil to the power transmission unit can be reduced.

  Further, the cooling oil passage includes a first oil passage communicating with the first motor / generator and a second oil passage communicating with the second motor / generator, and the oil passage through which the oil flows is defined as the first oil passage. A second switching valve for switching to the second oil passage. For this reason, oil can be supplied to one of the motors / generators in a concentrated manner, so that the cooling performance can be improved. As a result, since the amount of oil discharged from the first oil pump or the second oil pump can be reduced, the first oil pump or the second oil pump can be reduced in size. In addition, power loss for driving the first oil pump and the second oil pump can be reduced.

  In addition, when the temperature of one motor / generator of each motor / generator is high, the second switching valve is switched to supply oil to that one motor / generator. When the temperature of the other motor / generator is high, the oil is supplied to the other motor / generator. Therefore, the motor / generator on the side where the temperature has become high can be intensively cooled. As a result, since the amount of oil discharged from the first oil pump or the second oil pump can be reduced, the first oil pump or the second oil pump can be reduced in size. In addition, power loss for driving the first oil pump and the second oil pump can be reduced.

  Further, the second switching valve switches the oil to flow to the motor / generator having a large acting load. Therefore, even if the temperature of each motor / generator is relatively low, the load that acts by supplying oil to the motor / generator on the side that is likely to become hot due to the large load that acts The motor / generator on the larger side can be cooled in advance. As a result, it is possible to suppress or prevent an excessive increase in temperature due to a large acting load.

It is a figure for demonstrating an example of the hydraulic circuit which can be made into the object of the hydraulic control apparatus of the hybrid vehicle which concerns on this invention. It is a skeleton diagram showing a configuration example of a drive system of a hybrid vehicle that can use the present invention. It is a flowchart for demonstrating an example of switching control of the switching valve in FIG. FIG. 6 is a diagram for explaining another example of a hydraulic circuit that can be a target of the hydraulic control device for a hybrid vehicle according to the present invention. It is a flowchart for demonstrating an example of switching control of the switching valve in FIG.

  Next, the present invention will be specifically described with reference to the drawings. FIG. 2 shows a configuration example of a drive system of a hybrid vehicle Ve that can use the present invention. The vehicle Ve shown in FIG. 2 has two types of power sources having different power generation principles. That is, the engine 1 and first and second motor generators (MG1, MG2) 2, 3 as electric motors having a power generation function are provided as power sources.

  The engine 1 is a power engine that outputs power by burning fuel such as a gasoline engine, a diesel engine, or a natural gas engine, and preferably the load can be electrically controlled by a throttle opening or the like, and a predetermined load can be set. On the other hand, it is an internal combustion engine that can be set to an optimum operating point with the best fuel efficiency by controlling the rotational speed.

  Each of the motor generators 2 and 3 is constituted by a synchronous motor having a permanent magnet in a rotor as an example, and functions as a generator and a motor, in other words, a power running function that converts electric energy into kinetic energy. And a regenerative function for converting kinetic energy into electrical energy. The two motor generators 2 and 3 have rotors 2a and 3a and stators 2b and 3b, respectively, and both the stators 2b and 3b are fixed to the casing 4 or the like.

  In addition, coils 2c and 3c are formed around the stators 2b and 3b of the motor generators 2 and 3 by winding a copper wire or the like. A storage battery (not shown) is connected to the coils 2c and 3c via an inverter, and the inverters connected to the coils 2c and 3c are connected so as to be able to exchange power. Therefore, one motor / generator 2 (or motor / generator 3) is caused to function as a generator, and the generated electric power is supplied to the other motor / generator 3 (or motor / generator 2) so as to function as a motor. It is configured to be possible. Further, the motor generators 2 and 3 can be supplied with electric power from the battery so that the motor generators 2 and 3 can function as electric motors.

  The power transmission path is configured such that the power output from the power source by the engine 1 and the motor generators 2 and 3 is transmitted to the drive wheels 6 through the differential 5. Specifically, the output shaft 1 a of the engine 1 is connected to the power split device 7. The power split device 7 is a three-element differential gear mechanism having a power combining or splitting function, and can therefore be configured using a single pinion planetary gear mechanism or a double pinion planetary gear mechanism. In the example shown in FIG. 2, the carrier 7c is an input element, the sun gear 7s is a reaction element, and the ring gear 7r is an output element.

  That is, a ring gear 7r as an internal gear is arranged concentrically with the sun gear 7s on the outer peripheral side of the sun gear 7s as an external gear, and the pinion gear 7p meshing with the sun gear 7s and the ring gear 7r is used as a carrier. 7c is held so that it can rotate and revolve freely. An output shaft 1a of the engine 1, that is, an output shaft 1a such as a crankshaft is connected to the carrier 7c. Therefore, the carrier 7c is an input element. A power transmission mechanism such as a starting clutch or a torque converter (a torque converter with a lock-up clutch) may be appropriately provided between the engine 1 and the carrier 7c.

  A first motor / generator (MG1) 2 is connected to the sun gear 7s of the power split device 7. That is, the rotor 2a of the first motor / generator 2 is connected to the sun gear 7s, and as described above, the stator 2b of the first motor / generator 2 is fixed to the casing 4 or the like, and the sun gear 7s serves as a reaction force element. Yes.

  The second motor / generator (MG2) 3 is connected to the ring gear 7r of the power split device 7 so as to be able to transmit power, and the output shaft 8 is connected to the output side thereof. That is, the rotor 3a of the second motor / generator 3 is coupled to the ring gear 7r. Therefore, the ring gear 7r is an output element.

  The output shaft 8 and the drive wheel 6 are coupled via a differential 5 and a drive shaft 9 so that power can be transmitted.

  In the vehicle Ve shown in FIG. 2, when the engine 1 is operated and the engine torque is transmitted to the carrier 7c of the power split device 7, the reaction torque is received by the first motor / generator 2, and the engine torque is reduced. It is transmitted to the ring gear 7r. The torque transmitted to the ring gear 7r is transmitted to the driving wheel 6 via the differential 5, and a driving force is generated. In the power split device 7, it is possible to control the gear ratio between the carrier 7c as the input element and the ring gear 7r as the output element by the differential action of the sun gear 7s, the carrier 7c, and the ring gear 7r. Specifically, the engine speed can be controlled steplessly (continuously) by controlling the output of the first motor / generator 2 responsible for the reaction torque. That is, the power split device 7 has a function as a continuously variable transmission.

  As described above, when the first motor / generator 2 is responsible for the reaction force torque, the rotation direction of the first motor / generator 2 is selectively switched to forward rotation, stop, reverse rotation, and the like based on various conditions. . For example, when the first motor / generator 2 rotates in the forward direction and takes charge of the reaction torque, the first motor / generator 2 is regeneratively controlled to charge the battery with the electric power generated by the first motor / generator 2, or to the inverter. To the second motor / generator 3 to control the power running of the second motor / generator 3. That is, the second motor / generator 3 is driven as an electric motor, and the torque is transmitted to the drive wheels 6 via the differential 5 and the drive shaft 9. On the other hand, when the first motor / generator 2 rotates in the reverse direction and takes on the reaction torque, the first motor / generator 2 is subjected to power running control. The electric power supplied to the first motor / generator 2 can be supplied from the battery or the second motor / generator 3. That is, the second motor / generator 3 can be regeneratively controlled and the electric power can be supplied to the first motor / generator 2 via the inverter.

  The power transmission device in FIG. 2 includes temperature sensors 10 and 11 that detect the temperature of each motor / generator, a sensor 12 that detects the rotational speed of the drive shaft 9, or an accelerator opening sensor that detects an accelerator opening (not shown). The signals detected by these sensors are input to an electronic control unit (ECU) 13. The electronic control device 13 stores various data obtained in advance through experiments and simulations, and switches between each motor / generator and a hydraulic circuit (to be described later) according to each signal input to the electronic control device 13. A signal is output to a valve or an electric oil pump.

  As described above, a driving mode (hereinafter referred to as HV) in which power is output from the engine 1 and the first motor / generator 2 or the second motor / generator 3 is subjected to power running control to output power and output the driving force of the vehicle Ve. In the travel mode, the torque for driving the vehicle acts on the gears 7s, 7r, and 7p in the power split device 7. Therefore, oil is supplied to the gears 7s, 7r, and 7p in order to reduce the friction loss of the gears 7s, 7r, and 7p or to prevent seizure due to heat generation of the gears 7s, 7r, and 7p. In addition, since the first motor / generator 2 and the second motor / generator 3 output reaction force or assist torque, the motor / generators 2 and 3 are oils for cooling heat generated by copper loss and iron loss. Is supplied.

  On the other hand, in a state where the engine 1 is stopped, that is, in a state where the carrier 7c in the power split device 7 is not rotating, a traveling mode (hereinafter referred to as driving mode) that outputs the driving force of the vehicle Ve only by the power output from the second motor / generator 3. In the EV traveling mode, since no fuel is supplied to the engine 1, the gears 7s, 7r, 7p in the power split device 7 are connected to the gears 7s, 7r, 7p in the HV traveling mode. Torque for running the vehicle Ve, such as the acting torque, is not input. That is, the gears 7s, 7r, and 7p are idled by the torque output from the second motor / generator 3. Note that the carrier 7 c is not rotated by the inertial force of the engine 1. Therefore, in the EV traveling mode, only the oil that can reduce the drag loss is supplied to the power split device 7. On the other hand, since a large load for outputting the driving force of the vehicle Ve acts on the second motor / generator 3, oil is supplied so that the temperature of the second motor / generator 3 does not rise excessively based on the load. Supply.

  Next, an example of a hydraulic circuit for supplying oil to the motor generators 2 and 3 and the power split device 7 will be described. FIG. 1 is a diagram for explaining the configuration of the hydraulic circuit. The hydraulic circuit shown in FIG. 1 includes a mechanical oil pump (MOP) 14 that is connected to the output shaft 1a of the engine 1 and is driven by power output from the engine 1, and an electric oil pump (EOP) 15 that is driven by an electric motor. The oil pumps 14 and 15 are provided as a hydraulic pressure source. Each oil pump 14 and 15 pumps up and outputs oil stored in an oil pan (not shown). Between the oil pan and the oil pumps 14 and 15, metal powder mixed in the oil or the like is used. Strainers 16 and 17 for removing foreign substances are provided.

  First, the oil output from the mechanical oil pump 14 flows through the oil passage 18 and is supplied to the power split device 7. Specifically, an oil passage 18 is connected to the mechanical oil pump 14, and a check valve 19 that prevents oil from flowing into the mechanical oil pump 14 side is provided in the oil passage 18. The oil is configured to be supplied to the power split device 7 via. This is because when the engine 1 is driven, that is, in the HV traveling mode, a large torque is input from the engine 1 to the power split device 7 to drive the vehicle Ve, so that oil is always supplied to the power split device 7. It is configured to be able to.

  On the other hand, the oil discharged from the mechanical oil pump 14 is configured to be supplied to the motor / generators 2 and 3 in addition to the power split device 7. Specifically, a check valve 21 for preventing oil from flowing into the mechanical oil pump 14 side is provided in the oil path 18 branched from the oil path 18 communicating with the power split device 7, and the check valve Oil flows into the oil passage 22 connected to the output side of the check valve 21 through 21. Further, an oil cooler (O / C) 23 is provided in the oil passage 22 and is configured to cool the oil flowing through the oil passage 22. The oil cooled by the oil cooler 23 flows through the oil passages 24 and 25 communicating with the motor generators 2 and 3 and is supplied to the motor generators 2 and 3. The oil passage 22 corresponds to the cooling oil passage in the present invention, the oil passage 24 corresponds to the first oil passage in the present invention, and the oil passage 25 corresponds to the second oil passage in the present invention.

  Accordingly, since the engine 1 is always in operation in the HV traveling mode, the mechanical oil pump 14 connected to the output shaft 1a of the engine 1 is driven to drive the power split device 7 and each motor / generator 2. 3 is configured to supply oil.

  Next, a hydraulic circuit for supplying the oil discharged from the electric oil pump 15 to the motor generators 2 and 3 and the power split device 7 will be described. As described above, in the EV traveling mode, the output shaft 1a of the engine 1 does not rotate, so that the mechanical oil pump 14 is stopped. Therefore, in the example shown in FIG. 1, an electric oil pump 15 is provided. The electric oil pump 15 is an oil pump that can be driven independently of the traveling of the vehicle Ve by being electrically controlled. The electric oil pump 15 communicates with the oil passage 22 via a switching valve 26 described later. A check valve 27 for preventing oil from flowing to the electric oil pump 15 side is provided on the output side of the switching valve 26. This is to prevent the oil discharged from the mechanical oil pump 14 in the HV traveling mode and flowing to the first motor / generator 2 and the second motor / generator 3 from flowing back to the electric oil pump 15 side. is there. The oil output from the electric oil pump 15 flows through the oil passages 24 and 25 via the oil passage 22 and the oil cooler 23 provided in the oil passage 22, and is supplied to the motor generators 2 and 3. It is comprised so that.

  On the other hand, by switching the switching valve 26, the power split device 7 can be made to flow oil. Specifically, an oil passage 28 communicating with the power split device 7 other than the oil passage 22 is connected to the switching valve 26. More specifically, an oil passage 28 communicating with the output side of the check valve 19 provided in the oil passage 18 is connected to the switching valve 26. Therefore, it is configured such that oil can be supplied to the power split device 7 by switching the output port of the switching valve 26 from the output port communicating with the oil passage 22 to the output port communicating with the oil passage 28. . Note that the switching valve 26 may be any valve that can selectively switch the oil passage to be communicated. Therefore, the switching valve 26 may be an electromagnetic valve that switches electrically, or a switch that mechanically switches. It may be a valve.

  As described above, the oil output from the electric oil pump 15 is supplied to the motor generators 2 and 3, so that the oil is supplied to the motor generators 2 and 3 even in the EV traveling mode. Can be supplied. As a result, even if the motor / generator is driven to generate heat to output the power of the vehicle Ve, the heat can be cooled by the oil output from the electric oil pump 15. In addition, by switching the switching valve 26 and supplying oil to the power split device 7, drag loss in the power split device 7 can be reduced. That is, when the vehicle Ve is driven, drag loss due to rotation of the gears 7s, 7r, 7p in the power split device 7 can be reduced.

  Next, an example of control of the hydraulic circuit described above will be described. FIG. 3 is a flowchart for explaining the control example, and specifically, is a flowchart executed when the vehicle Ve is traveling in the EV traveling mode. Note that the control in FIG. 3 is repeatedly executed at predetermined time intervals. First, when the vehicle Ve travels in the EV travel mode, it is determined whether or not the temperature of the second motor / generator 3 is higher than a threshold value α (step S11). This can be detected by a temperature sensor 11 provided in the second motor / generator 3. The threshold value α in step S11 is a temperature stored in advance based on the characteristics or durability of the second motor / generator 3. If the determination in step S11 is affirmative, that is, if the temperature of the second motor / generator 3 is higher than the threshold value α, the electric oil pump 15 and the oil passage 22 are communicated with each other, that is, each motor. The switching valve 26 is switched so that oil is supplied from the electric oil pump 15 to the generators 2 and 3 (step S12), and the electric oil pump 15 is operated (step S13). That is, oil is supplied from the electric oil pump 15 to the motor generators 2 and 3. The oil flow when the oil is supplied from the electric oil pump 15 to the motor / generators 2 and 3 is shown by a solid line in FIG.

  On the other hand, when a negative determination is made in step S11, that is, when the temperature of the second motor / generator 3 is equal to or lower than the threshold value α, the output torque required for the second motor / generator 3 is the threshold value β. It is determined whether it is larger (step S14). The output torque required for the second motor / generator 3 in step S14 can determine the driving force required by the driver based on, for example, a signal detected by an accelerator opening sensor or the like. Further, the threshold value β in step S14 is determined in advance in the electronic control unit 13 or the like by preliminarily determining an output torque at which the second motor / generator 3 generates excessive heat from experiments or characteristics of the second motor / generator 3. This is the stored value. If the determination in step S14 is affirmative, that is, if the output torque required for the second motor / generator 3 is larger than the threshold value β, the electric oil pump 15 and the oil passage 22 are communicated with each other. That is, the switching valve 26 is switched so that oil is supplied from the electric oil pump 15 to the motor generators 2 and 3 (step S12), and the electric oil pump 15 is operated (step S13). That is, oil is supplied from the electric oil pump 15 to the motor generators 2 and 3.

  On the other hand, when a negative determination is made in step S14, that is, when the output torque required for the second motor / generator 3 is equal to or less than the threshold value β, the cumulative travel distance in the EV travel mode is less than the threshold value γ. It is determined whether or not it is long (step S15). The cumulative travel distance in step S15 is the distance traveled by the vehicle Ve after the EV travel mode is set, and is calculated based on, for example, a signal detected by the sensor 12 that detects the rotational speed of the drive shaft 9. be able to. The determination in step S15 is to determine whether or not it is necessary to supply oil to each gear 7s, 7r, 7p in the power split device 7 because the accumulated traveling distance in the EV traveling mode is long. When the travel distance is long, there is a possibility that oil is scattered or dripped from each gear 7s, 7r, 7p in the power split device 7. That is, it is necessary to improve lubricity, and the threshold value γ can be determined in advance by experiments and simulations such as the number of revolutions at which the oil supplied to the gears 7s, 7r, 7p scatters or drops.

  Therefore, when a negative determination is made in step S15, that is, when the cumulative travel distance in the EV travel mode is equal to or less than the threshold value γ, the oil is not supplied to the power split device 7 or the electric oil pump. Return without driving 15. On the contrary, if the determination in step S15 is affirmative, that is, if the cumulative travel distance in the EV travel mode is equal to or greater than the threshold value γ, the gears 7s, 7r, 7p in the power split device 7 are In order to improve lubricity, the switching valve 26 is switched so that the oil output from the electric oil pump 15 is supplied to the power split device 7 (step S16), and the electric oil pump is operated (step S13). That is, oil is supplied from the electric oil pump 15 to the power split device 7. Note that the cumulative travel distance is reset by switching the switching valve 26 so that the oil output from the electric oil pump 15 in step S16 is supplied to the power split device 7. That is, the cumulative travel distance starts to be counted again from the time when the switching valve 26 is switched. The oil flow when oil is supplied from the electric oil pump 15 to the power split device 7 is indicated by broken lines in FIG.

  As described above, when the temperature of the second motor / generator 3 is high or the output torque is high, the second motor / generator 3 can be cooled by supplying oil to the second motor / generator 3. As a result, the durability of the second motor / generator 3 can be improved. Moreover, since oil can be supplied to the power split device 7 by switching the switching valve 26, the drag loss of the power split device 7 can be reduced. Furthermore, oil is supplied to the power split device 7 only when the cumulative travel distance is equal to or greater than the threshold value γ, and when oil is not supplied to the second motor / generator 3 or the power split device 7, The electric oil pump 15 is stopped. As a result, it is possible to reduce electrical loss due to excessive driving of the electric oil pump 15, and reduce stirring loss due to excessive supply of oil to the gears 7s, 7r, 7p. be able to.

  The above-described configuration is not limited to outputting power by the second motor / generator 3 in the EV travel mode. For example, the vehicle Ve travels by reversely rotating the first motor / generator 2 by performing power running control. Power can also be output. Therefore, in the vehicle that outputs power by the first motor / generator 2, it is sufficient to determine whether or not the temperature of the first motor / generator 2 is higher than the threshold in step S11 in the flowchart shown in FIG. In S14, it may be determined whether or not the output torque of the first motor / generator 2 is higher than a threshold value. When the vehicle is driven by the power output from the first motor / generator 2, the vehicle is input to the power split device 7 rather than when the vehicle power is driven only by the power output from the second motor / generator 3. Since the torque increases, it is preferable to switch the switching valve 26 so that the threshold value γ in step S15 is reduced, that is, the cumulative travel distance in the EV mode is shortened.

  Furthermore, the hydraulic control apparatus according to the present invention is configured so that each of the motor / generators 2 and 3 can be cooled in a concentrated manner. FIG. 4 shows the hydraulic circuit. The hydraulic circuit shown in FIG. 4 is further provided with a switching valve 29 that switches an oil passage through which oil flows between an oil passage 24 and an oil passage 25 in the oil passage 22 in FIG. Note that the switching valve 26 provided in the oil passage 22 only needs to be able to selectively switch the oil passage that outputs oil, and therefore is an electromagnetic valve that performs electrical switching or a valve that performs mechanical switching. There may be.

  By providing the switching valve 29 in the oil passage 22 as described above, oil is concentrated on one of the motor / generators 2 (3). Therefore, since the cooling performance of the motor / generator 2 (3) on the oil supply side is improved, the capacity of the mechanical oil pump 14 or the electric oil pump 15 serving as a hydraulic source can be reduced. Mountability and power loss of the oil pumps 14 and 15 can be reduced.

  Next, a control example for switching the switching valve 29 described above will be described. FIG. 5 is a flowchart for explaining the control. Note that the switching valve 29 shown in FIG. 4 is not limited to the EV travel mode, and the same effect can be achieved even in the HV travel mode. Without explaining. The control shown in FIG. 5 is repeatedly executed every predetermined time. First, whether or not the temperature of the second motor / generator (MG2) 3, that is, the temperature detected by the temperature sensor 11 is lower than a threshold value. Is determined (step S21). The threshold value in step S21 is a temperature set below the temperature at which the durability and output torque of the second motor / generator 3 decrease, and is the same temperature as the threshold value α in the control shown in FIG. The temperature may be equal to or lower than the threshold value α. When a negative determination is made in step S21, that is, when the temperature of the second motor / generator 3 is equal to or higher than the threshold value, the switching valve 29 is switched so that the oil passage 22 and the oil passage 25 communicate with each other. (Step S22), return.

  On the other hand, when a negative determination is made in step S21, that is, when the temperature of the first motor / generator (MG1) 2 is equal to or lower than the threshold value, the temperature of the first motor / generator 2, that is, detected by the temperature sensor 10 is detected. It is determined whether the measured temperature is lower than a threshold value (step S23). The threshold value in step S23 is a temperature set to be equal to or lower than the temperature at which the durability and output torque of the first motor / generator 2 are reduced, as in step S21. When a negative determination is made in step 23, that is, when the temperature of the first motor / generator 2 is equal to or higher than the threshold value, the switching valve 29 is switched so that the oil passage 22 and the oil passage 24 communicate with each other ( Step S24) and return.

  On the contrary, if the determination in step S23 is affirmative, that is, if the temperature of the first motor / generator 2 is lower than the threshold value, the first motor / generator 2 and the second motor / generator 3 Each temperature is lower than the temperature at which durability and output torque are reduced. On the other hand, when each motor / generator 2 or 3 is driven or rotated, copper loss or iron loss may occur, and the temperature may rise. For this reason, the switching valve 25 is controlled in advance so that oil is supplied to the motor generator 2 (3) on the side where the temperature is likely to rise. Specifically, after a positive determination is made in step S23, it is determined whether or not the load factor of the second motor / generator 3 is lower than the load factor of the first motor / generator 2 (step S25). That is, the load factor that is the ratio of the maximum power that can be energized according to the characteristics of the motor generators 2 and 3 and the power that is actually energized is compared. By this step S25, it is possible to determine the motor / generator 2 (3) that is highly likely to generate heat. Therefore, the switching valve 29 is switched so that oil is supplied to the motor / generator 2 (3) on the side that is likely to generate heat.

  Specifically, when a negative determination is made in step S25, there is a high possibility that the load factor of the second motor / generator 3 is higher than the load factor of the first motor / generator 2 and generates a high temperature. The switching valve 29 is switched so that the oil passage 22 and the oil passage 25 communicate with each other (step S22), and the process returns. On the other hand, if the determination in step S25 is affirmative, the load factor of the first motor / generator 2 is higher than the load factor of the second motor / generator 3 and is likely to generate a high temperature. The switching valve 29 is switched so that the oil passage 22 and the oil passage 24 communicate with each other (step S24), and the process returns.

  As described above, by switching the switching valve 29 according to the temperature and load factor of each motor / generator 2, 3, the motor / generator 2 (3) on the high temperature side and the possibility of high temperature are high. Since oil can be concentrated and supplied to the motor generator 2 (3) on the side, the cooling performance for cooling the motor generators 2 and 3 can be improved, and the capacity of the hydraulic sources 14 and 15 can be increased. Can be reduced.

  Note that by combining the control of FIG. 3 and FIG. 5, oil can be supplied concentratedly to each motor / generator 2, 3 even in the EV travel mode. That is, after switching the switching valve 29 in step S22 or step S24 in FIG. 5, the travel mode of the vehicle Ve is determined, and when it is in the EV travel mode, the EV travel mode is executed by executing the control shown in FIG. Even so, oil can be supplied to the motor generators 2 and 3 in a concentrated manner.

  Note that the determination in step S25 in FIG. 5 is not limited to the determination based on the load factor of each motor / generator 2 or 3, but for example, the torque required for each motor / generator 2 or 3 or each motor / generator 2 or 3 is determined. 3 can be determined using various parameters such as the power supplied to the power source 3.

  DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... 1st motor generator, 3 ... 2nd motor generator, 7 ... Power split device, 18, 20, 22, 24, 25, 28 ... Oil path, 16, 29 ... Switching valve.

Claims (6)

A first rotating element connected to the internal combustion engine, a second rotating element connected to the first motor / generator, and a third rotating element connected to the output member of the vehicle and connected to the second motor / generator. In a hydraulic control device for a hybrid vehicle including a power split device having
A cooling oil passage communicating with each motor / generator;
A lubricating oil passage for supplying oil to a power transmission unit in the power split device;
A first oil pump that is driven by the power of the internal combustion engine and communicates with the cooling oil passage and the lubricating oil passage;
A second oil pump that is driven by the power of another electric motor and communicates with the cooling oil passage and the lubricating oil passage;
A hybrid comprising: a first switching valve that selectively switches an oil passage to which oil output from the second oil pump is supplied to the cooling oil passage and the lubrication oil passage. Vehicle hydraulic control device.   The first switching valve is an oil passage through which oil discharged from the second oil pump flows when the temperature of a motor / generator that outputs power to drive the vehicle is equal to or higher than a first threshold value. Is switched to the cooling oil passage side, and the vehicle is set in a state where the temperature of the motor / generator that outputs power to drive the vehicle is lower than a first threshold value and the first oil pump is not driven. 2. The hydraulic control device for a hybrid vehicle according to claim 1, wherein an oil passage through which oil discharged from the second oil pump flows is switched to the lubricating oil passage when traveling over a distance. 3. The cooling oil passage includes a first oil passage communicating with the first motor / generator and a second oil passage communicating with the second motor / generator,
3. The hydraulic pressure of the hybrid vehicle according to claim 1, further comprising a second switching valve that selectively switches an oil passage through which oil flows to the first oil passage and the second oil passage. 4. Control device.   The second switching valve is an oil that communicates a flow path through which oil flows when the temperature of one of the motor generators is equal to or higher than a second threshold value. When the temperature of the one motor / generator is lower than the second threshold value and the temperature of the other motor / generator is higher than the third threshold value, the flow path through which the oil flows is 4. The hydraulic control apparatus for a hybrid vehicle according to claim 3, wherein the hydraulic path is switched to an oil passage communicating with the motor / generator.   When the load acting on the first motor / generator is larger than the load acting on the second motor / generator, the second switching valve switches an oil passage through which oil flows to the first oil passage, 5. The oil passage through which oil flows is switched to the second oil passage when the load acting on one motor / generator is smaller than the load acting on the second motor / generator. Hydraulic control device for hybrid vehicles.   The hydraulic control device for a hybrid vehicle according to any one of claims 1 to 5, further comprising an oil cooler that cools oil supplied to the cooling oil passage.

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