TWI779422B - hybrid vehicle - Google Patents

Abstract

[Problem] To provide a hybrid vehicle capable of stabilizing and suppressing vibration during stop control of an internal combustion engine. [Solution] The vehicle control device for controlling the internal combustion engine, the motor generator for power generation, and the motor generator for driving has a torque acquisition unit and a rotation fluctuation determination unit. After the fuel is injected by the injection valve and the throttle valve is fully closed, the torque acquisition part acquires the torque of the motor generator for power generation necessary to make the internal combustion engine reach the engine speed during power generation at each predetermined time, and also Yes, the rotation fluctuation determination unit judges whether the rotation speed fluctuation of the motor generator for power generation is equal to or less than a predetermined first threshold every predetermined time; The motor generator for power generation is controlled to be driven by the torque obtained by the torque obtaining unit, and the internal combustion engine is controlled to be stopped using the motor generator for power generation when it is determined that the rotation speed fluctuation is equal to or less than a first threshold value.

Description

hybrid vehicle

The present invention relates to hybrid vehicles.

Proposals include various technologies related to hybrid vehicles equipped with internal combustion engines, motor generators for driving, motor generators for power generation, and batteries.

For example, the control device for a hybrid vehicle described in the following Patent Document 1 is applied to a hybrid vehicle including an internal combustion engine equipped with a supercharger, and a motor generator connected to an output shaft of the internal combustion engine; The control device includes an ECU that controls the motor generator. The internal combustion engine is provided with a bypass passage for bypassing the compressor of the supercharger, and a bypass valve for opening and closing the bypass passage. When the internal combustion engine is stopped, the control device of the hybrid vehicle is configured to control the ECU to stop the internal combustion engine by using the motor generator to reduce the compression reaction force of the internal combustion engine and suppress vibration after opening the bypass valve. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Unexamined Patent Publication No. 2015-85849

[Problem to be solved by the invention]

However, in the control device for a hybrid vehicle described in Patent Document 1 above, a bypass circuit composed of a bypass passage for bypassing the compressor of the supercharger and a bypass valve for opening and closing the bypass passage is provided. The mechanism is necessary, so there is a problem that the number of parts increases and the manufacturing cost increases. Furthermore, since there is no reaction force detection means for detecting the state of the compression reaction force of the internal combustion engine, there is a possibility that the vibration reduction effect may be sporadically produced.

Here, the present invention is created in view of such a problem, and an object of the present invention is to provide a hybrid vehicle capable of stabilizing and suppressing vibration during stop control of an internal combustion engine. [Means to solve the problem]

In order to solve the above-mentioned problems, the first invention of the present invention is a hybrid vehicle comprising: an internal combustion engine; a power generator connected to the internal combustion engine; and a battery connected via the power generator. to be charged; the driving motor generator, which uses the discharged power of the aforementioned battery to drive the drive wheels; the rotational speed obtaining device, which obtains the motor generator rotational speed of the aforementioned power generating motor generator; and the vehicle control device, which controls the aforementioned An internal combustion engine, the aforementioned motor generator for power generation, and the aforementioned motor generator for driving; wherein the aforementioned internal combustion engine has: an intake pipe connected to the upstream side of an intake manifold; a throttle valve that can Adjusting the degree of opening of the intake pipe; and a plurality of fuel injection valves for injecting fuel into each cylinder of the internal combustion engine; When the combustion engine is stopped, after the fuel injection by the plurality of fuel injection valves is stopped and the throttle valve is fully closed, the torque acquisition unit acquires torque at each predetermined time in order to make the internal combustion engine an engine for power generation. The torque of the motor-generator for power generation necessary for the rotation speed, and the rotation fluctuation determination unit determines whether the rotation speed fluctuation of the motor-generator rotation speed is equal to or less than a predetermined first threshold value every predetermined time; the vehicle control device, When it is determined by the rotation fluctuation determination unit that the rotation speed fluctuation of the motor generator rotation speed is larger than the first threshold value, control to drive the power generation motor generator with the torque; when it is determined by the rotation fluctuation determination unit When the rotational speed fluctuation of the motor generator rotational speed is equal to or less than the first threshold value, control is performed to stop the internal combustion engine using the power generating motor generator.

Next, a second invention of the present invention is a hybrid vehicle comprising: an internal combustion engine; a power generating motor generator connected to the internal combustion engine; a battery charged via the power generating motor generator; A motor generator for driving that drives drive wheels using the discharged power of the battery; a vehicle control device that controls the internal combustion engine, the motor generator for power generation, and the motor generator for drive; The combustion engine has: an intake pipe, which is connected to the upstream side of the intake manifold; a throttle valve, which can adjust the opening degree of the aforementioned intake pipe; and a plurality of fuel injection valves, which inject fuel into the aforementioned interior. In each cylinder of the combustion engine; the aforementioned vehicle control device has a torque acquisition unit and a torque fluctuation determination unit, wherein, when the aforementioned internal combustion engine is stopped, the fuel injection caused by the plurality of the aforementioned fuel injection valves is stopped and the aforementioned throttling After the valve is fully closed, the torque acquisition unit acquires the torque of the aforementioned motor generator for power generation necessary for the internal combustion engine to attain the engine speed for power generation every predetermined time, and the torque fluctuation determination unit determines Whether the torque variation of the torque acquired by the torque acquisition unit is equal to or less than a predetermined second threshold value; the vehicle control device determines that the torque variation of the torque is larger than the second threshold value by the torque variation determination unit Next, control to drive the motor generator for power generation with the torque; and control to drive the motor generator for power generation by using the motor generator for power generation when it is determined by the torque fluctuation determination unit that the torque fluctuation of the torque is equal to or less than the second threshold value. The internal combustion engine stops.

Next, in the third invention of the present invention, in the hybrid vehicle related to the above-mentioned first invention or the second invention, an intake pressure obtaining device for obtaining the intake pressure of the intake manifold is further provided; The device has an intake gas pressure judging unit for judging whether or not the intake air pressure of the intake manifold is equal to or less than a predetermined third threshold every predetermined time; When the engine is stopped, after the fuel injection by the plurality of fuel injection valves is stopped and the throttle valve is fully closed, furthermore, the intake air pressure of the intake manifold is determined by the intake air pressure determination unit to be In the case where the third threshold value is equal to or lower than the third threshold value, the internal combustion engine is controlled to be stopped using the power generating motor generator.

Next, in a fourth invention of the present invention, in the hybrid vehicle according to any one of the above-mentioned first invention to the third invention, the vehicle control device uses the electric power generating motor generator to make the internal When the combustion engine is stopped, it is controlled to regeneratively drive the electric generator for power generation. [Invention effect]

According to the first invention, when the internal combustion engine is stopped, the vehicle control device stops fuel injection by a plurality of fuel injection valves and fully closes the throttle valve, and then determines whether the power generation is generated by the rotation fluctuation determination unit every predetermined time. Whether or not the rotational speed variation of the motor generator rotational speed by the motor generator is equal to or less than a predetermined second threshold value.

Next, when the vehicle control device determines that the rotation speed variation of the motor generator rotation speed of the power generating motor generator is larger than the first threshold value, the vehicle control device controls the engine rotation speed of the internal combustion engine to be the engine rotation speed at the time of power generation. necessary torque to drive a motor generator for power generation. On the other hand, the vehicle control device controls to stop the internal combustion engine using the power generating motor generator when it is determined that the motor generator speed fluctuation of the power generating motor generator is equal to or less than the first threshold value.

As a result, when the variation in the rotational speed of the motor generator for power generation is greater than the predetermined first threshold value, the compression reaction force of the internal combustion engine cannot be sufficiently reduced, and the motor generator for power generation is driven to This becomes the engine speed at the time of power generation, whereby a sudden drop in the engine speed can be prevented, and vibration at the time of stop control of the internal combustion engine can be suppressed. Furthermore, when the rotational speed variation of the motor generator rotational speed of the electric generator for power generation is equal to or less than the predetermined first threshold value, the compression reaction force of the internal combustion engine is definitely lowered, even if there is no detection of the compression reaction force of the internal combustion engine. The state reaction force detection device can also stabilize and suppress the vibration during the stop control of the internal combustion engine by using a motor generator for power generation.

According to the second invention, when the internal combustion engine is stopped, the vehicle control device stops the fuel injection by the plurality of fuel injection valves and fully closes the throttle valve, and then obtains the control system for the internal combustion engine every predetermined time. The torque of the motor generator for power generation is required to become the engine speed at the time of power generation. Next, the vehicle control device judges whether or not the torque variation of the acquired torque of the power-generating motor generator is equal to or less than a predetermined second threshold value.

Next, when the vehicle control device determines that the torque fluctuation of the torque of the motor generator for power generation is larger than the second threshold value, it controls the engine speed of the internal combustion engine so that the engine speed of the internal combustion engine becomes the engine speed at the time of power generation. to drive a motor generator for power generation. On the other hand, the vehicle control device controls to stop the internal combustion engine using the power generating motor generator when it is determined that the torque variation of the torque of the power generating motor generator is equal to or less than the second threshold value.

As a result, when the torque fluctuation of the torque of the electric generator for power generation is greater than the predetermined second threshold value, since the compression reaction force of the internal combustion engine does not sufficiently decrease, the motor generator for power generation is driven to generate power. The engine speed can be lowered, thereby preventing a sudden drop in the engine speed, and suppressing vibration during stop control of the internal combustion engine. Furthermore, since the compression reaction force of the internal combustion engine is definitely lowered when the torque fluctuation of the torque of the motor generator for power generation is equal to or less than the predetermined second threshold value, even if there is no reaction to detect the state of the compression reaction force of the internal combustion engine, The force detection device can also stabilize and suppress vibration during stop control of the internal combustion engine by using a motor generator for power generation.

According to the third invention, when the internal combustion engine is stopped, the vehicle control device stops fuel injection by a plurality of fuel injection valves and fully closes the throttle valve, and further determines the intake manifold at every predetermined time. Check whether the intake pressure of the pipe is equal to or less than the predetermined third threshold. Next, the vehicle control device further controls to stop the internal combustion engine using the power generating motor generator when it is determined that the intake air pressure of the intake manifold is equal to or less than a third threshold value. Thus, when the intake pressure of the intake manifold is below the third threshold value, the compression reaction force of the internal combustion engine is definitely lowered, even if there is no reaction force detection device for detecting the state of the compression reaction force of the internal combustion engine , It is also possible to further stabilize and suppress the vibration during the stop control of the internal combustion engine.

According to the fourth invention, the vehicle control device stops the internal combustion engine by regeneratively driving the electric generator for power generation when the internal combustion engine is stopped. As a result, by regeneratively driving the electric generator for power generation and reducing the stop speed of the internal combustion engine, it is possible to further stabilize and suppress vibration during stop control of the internal combustion engine.

Hereinafter, the first to third embodiments of the hybrid vehicle according to the present invention will be described in detail with reference to the drawings. First, a schematic configuration of a hybrid vehicle 1 according to the first embodiment will be described with reference to FIG. 1 .

[the first embodiment] As shown in FIG. 1, a hybrid vehicle 1 related to the first embodiment mainly includes a battery 10, a power control unit (hereinafter referred to as "PCU (Power Control Unit)") 11, a diesel engine 20, Motor generator for driving (hereinafter referred to as "MG for driving") 31, motor generator for power generation (hereinafter referred to as "MG for power generation") 32, drive wheels 40, hybrid ECU (Electronic Control Unit) 51 , and engine ECU52.

The diesel engine 20 has a plurality of (for example, four in the present embodiment) cylinders 13A to 13D formed in an engine body 20A, and fuel injection valves 14A to 14D are provided in the respective cylinders 13A to 13D. The fuel injection valves 14A to 14D are supplied with fuel through a common rail (not shown) and a fuel pipe (not shown), and the fuel injection valves 14A to 14D are driven by a control signal from the engine ECU 52 to inject fuel to each cylinder 13A~13D.

The exhaust side of the exhaust manifold 46B is connected to the exhaust side of the diesel engine 20 . The outlet side of the exhaust manifold 46B is connected to the inlet side of the exhaust pipe 46A. Furthermore, the intake gas side of the diesel engine 20 is connected to the outlet side of the intake manifold 45B. The inlet side (upstream side) of the intake manifold 45B is connected to the outlet side of the intake pipe 45A. In the intake pipe 45A, a throttle device 47 is disposed. On the downstream side of the throttle device 47 in the intake pipe 45A, a pressure detection device 48 is provided. The pressure detection device 48 is, for example, a pressure sensor, and outputs a detection signal corresponding to the intake air pressure of the intake air flowing into the intake manifold 45B just before the intake manifold 45B to the engine ECU 52 .

The throttling device 47 is a throttle valve 47A that drives and adjusts the opening degree of the intake pipe 45A according to the control signal from the engine ECU 52 to adjust the flow rate of the intake gas. The engine ECU 52 is based on the detection signal from the throttle opening detection device 47S (for example, a throttle opening sensor) and the target throttle opening, and outputs a control signal to the throttle device 47 so as to adjust the intake pipe 45A. The opening degree of the throttle valve 47A. The engine ECU 52 obtains the target throttle opening degree based on the control signal for the diesel engine 20 input from the hybrid ECU 51 . Furthermore, the diesel engine 20 may include a turbocharger (for example, a variable nozzle turbine) not shown.

MG31 for driving and MG32 for power generation are electrical machines that convert electrical energy into mechanical energy, or convert mechanical energy into electrical energy. In this embodiment, a three-phase AC synchronous motor generator in which permanent magnets are embedded in a rotor is used as the driving MG31 and the generating MG32.

The hybrid vehicle 1 related to this embodiment is a series hybrid vehicle. In the hybrid vehicle 1 , the driving MG 31 drives drive wheels 40 by operating as a motor, and the generating MG 32 generates electricity by being driven by the diesel engine 20 . The power source for driving the driving MG 31 is the electric power generated by the generating MG 32 and the electric power stored in the battery 10 . Accordingly, driving MG 31 drives drive wheels 40 using the discharged electric power of battery 10 .

More specifically, the rotary shaft 21 of the diesel engine 20 and the rotary shaft 22 of the MG 32 for power generation are mechanically connected to each other through a gear 23 , and the rotation of the MG 32 for power generation follows the rotation of the rotary shaft 21 of the diesel engine 20 . The shaft 22 also rotates, and the MG 32 for power generation generates power. On the other hand, the rotating shaft 41 of the driving MG 31 is not mechanically connected to the respective rotating shafts 21 and 22 , but is mechanically connected to the drive shaft 42 via the power transmission gear 43 . The torque (driving force) output to the rotating shaft 41 of the driving MG 31 is transmitted to the driving shaft 42 through the power transmission gear 43 , and the driving shaft 42 is rotated by the driving force of the driving MG 31 . Then, as the drive shaft 42 rotates, the drive wheels 40 provided at both ends of the drive shaft 42 rotate.

The driving MG 31 operates as an electric motor during acceleration of the hybrid vehicle 1 and drives drive wheels 40 of the hybrid vehicle 1 . On the other hand, when the hybrid vehicle 1 is braking or the acceleration on a downhill slope is reduced, the driving MG 31 operates as a generator to perform regenerative power generation. The power generated by the driving MG 31 is supplied to the battery 10 through the PCU 11 .

The MG32 system for power generation is configured to generate power using power output from the diesel engine 20 (engine power generation). The engine-generated power generated in the generating MG32 is supplied from the generating MG32 to the drive MG31 through the PCU11, or is supplied from the generating MG32 to the battery 10 through the PCU11.

The PCU 11 is composed of two inverters installed corresponding to the driving MG31 and the generating MG32, and a booster that boosts the DC voltage supplied to each inverter to a voltage higher than the battery 10 (for example, 600V). pressure converter. The PCU 11 executes power conversion between the battery 10 and the driving MG 31 and the generating MG 32 based on a control signal from the hybrid ECU 51 . The PCU 11 is configured to be able to individually control the states of the driving MG 31 and the generating MG 32 . Next, the PCU 11 controls the driving MG 31 and the generating MG 32 based on the control signal input from the hybrid ECU 51 .

The battery 10 is a rechargeable DC power source. The rated voltage of the battery 10 is, for example, 300V to 450V. The battery 10 is configured to include, for example, a secondary battery (rechargeable battery). As the secondary battery, for example, a lithium ion battery can be used. The battery 10 may also include a battery pack composed of a plurality of secondary batteries (for example, lithium-ion batteries) connected in series and parallel or connected in series or parallel. Also, the secondary battery constituting the battery 10 is not limited to a lithium ion battery, and other secondary batteries (for example, nickel-metal hydride batteries) may also be used. An electrolyte type secondary battery or an all solid secondary battery may also be used. In addition, as the battery 10, a capacitor having a large capacity or the like may be used.

For the battery 10, a monitoring unit 61 for monitoring the state of the battery 10 is provided. The monitoring unit 61 includes various sensors that detect the state of the battery 10 (temperature, current, voltage, etc.). The PCU 11 is configured to detect the state of the battery 10 (storage level (SOC) and the like) based on the output of the monitoring unit 61 and output the detected state of the battery 10 (SOC and the like) to the hybrid ECU 51 .

Furthermore, with respect to the diesel engine 20, the monitoring means 62 which monitors the state of the diesel engine 20 is provided. The monitoring unit 62 includes various sensors for detecting the state of the diesel engine 20 (cooling water temperature, intake air volume, rotational speed, etc.). The engine ECU 52 is configured to detect the state of the diesel engine 20 based on the output of the monitoring unit 62 , and to output the detected state of the diesel engine 20 to the hybrid ECU 51 . Therefore, various sensors included in the monitoring unit 62 are connected to the input port of the engine ECU 52 .

Further, monitoring means 63 and 64 for respectively monitoring the states of the driving MG31 and the generating MG32 are provided for the driving MG31 and the generating MG32. Each of the monitoring units 63 and 64 includes various sensors for detecting the states (temperature, rotational speed, output current value, etc.) of the driving MG 31 and the generating MG 32 . The PCU 11 is configured to detect the states of the driving MG 31 and the generating MG 32 based on the outputs of the monitoring units 63 and 64 , and output the detected states of the driving MG 31 and the generating MG 32 to the hybrid ECU 51 . Therefore, various sensors included in the monitoring units 61 , 63 , and 64 are connected to the input ports of the PCU 11 .

The hybrid ECU51, the PCU11 and the engine ECU52 that constitute the vehicle control device of the hybrid vehicle 1 are composed of: a CPU (Central Processing Unit) as a computing device, a memory device, and an input/output port for inputting and outputting various signals (all not shown). icon). The memory device includes: RAM (Random Access Memory) as a working memory, and a storage bank (ROM (Read Only Memory), rewritable non-volatile memory, etc.) as a storage.

The hybrid ECU51, PCU11 and engine ECU52 receive signals from various devices (sensors, etc.) connected to the input port, and control various devices connected to the output port according to the received signals. Various controls are executed by the CPU executing the program stored in the memory device. However, the control performed by the hybrid ECU 51, the PCU 11, and the engine ECU 52 is not limited to processing by software, and may be performed by dedicated hardware (electronic circuit). The hybrid ECU51, PCU11, and engine ECU52 related to this embodiment function as an example of the "vehicle control device" related to the present invention.

The hybrid ECU 51 calculates the required output value of the diesel engine 20 and the required output values (for example, torque required value, etc.) of the driving MG 31 and the generating MG 32 . Next, the hybrid ECU51 transmits the output demand value of the diesel engine 20 to the engine ECU52, and transmits the output demand values (for example, torque demand values, etc.) of the drive MG31 and the power generation MG32 to the PCU11.

The PCU 11 controls the supply of electric power of the driving MG 31 and the generating MG 32 (and further, the output torques of the driving MG 31 and the generating MG 32 ) based on the output request value input from the hybrid ECU 51 . That is, the PCU 11 can control the magnitude (amplitude), frequency, etc. of electric power supplied to the driving MG 31 and the generating MG 32 based on the control signal input from the hybrid ECU 51 . Furthermore, the PCU 11 performs charge and discharge control of the battery 10 based on a control signal input from the hybrid ECU 51 .

Various devices connected to the input port of the hybrid ECU 51 include an accelerator opening degree sensor 65 and a vehicle speed sensor 66 . The accelerator opening sensor 65 detects the depression amount of the accelerator pedal (not shown) of the hybrid vehicle 1 as the accelerator opening, and outputs the detection result (a signal indicating the accelerator opening) to the hybrid ECU 51 . The vehicle speed sensor 66 detects the vehicle speed of the hybrid vehicle 1 and outputs the detection result (a signal indicating the vehicle speed) to the hybrid ECU 51 . The greater the stepping amount of the accelerator pedal of the hybrid ECU51 is, the more the driving force of the driving MG31 is increased.

The engine ECU 52 receives the output demand value of the diesel engine 20 from the hybrid ECU 51, and performs operation control of the diesel engine 20 (fuel injection control, air intake control) in order to generate kinetic energy corresponding to the output demand value in the diesel engine 20. Volume adjustment control, etc.). The engine power generation is performed by driving the diesel engine 20 , and the diesel engine 20 is stopped when the engine power generation is not performed. By driving the diesel engine 20 , engine-generated electric power is generated in the generating MG 32 . Furthermore, the engine ECU 52 receives detection values from various sensors included in the monitoring unit 62 and the pressure detection device 48 , and transmits each detection value to the hybrid ECU 51 .

The running system of the hybrid vehicle 1 is performed by driving the driving wheels 40 by the driving MG 31 . The hybrid ECU 51 starts the diesel engine 20 to start charging the battery 10 by the power generated by the engine when the SOC of the battery 10 is equal to or lower than the charging start SOC while the hybrid vehicle 1 is running. Next, the hybrid ECU 51 stops the diesel engine 20 to stop charging when the SOC of the battery 10 is equal to or higher than the fully charged SOC.

Next, an example of the engine stop control process in which the hybrid ECU 51 stops the diesel engine 20 will be described with reference to FIGS. 2 to 5 . Furthermore, the hybrid ECU 51 executes the processing procedure of the engine stop control processing shown in the flow of FIG. 2 when, for example, the diesel engine 20 is driven to charge the battery 10 . In addition, the programs shown in the flow chart in FIG. 2 are stored in advance in the memory for storage included in the hybrid ECU 51 . Then, once the hybrid ECU 51 is started, it starts the processing shown in FIG. 2 every predetermined time, that is, at predetermined time intervals (for example, several millimeters to several tens of millimeters), and proceeds to step S11.

As shown in FIG. 2, first, in step S11, the hybrid ECU 51 reads the engine stop request flag from the RAM, and determines whether it is set to "ON". That is, the hybrid ECU 51 determines whether or not a stop request command to stop the diesel engine 20 has been output to the engine ECU 52 . Furthermore, the engine stop request flag is set to "OFF" when the hybrid ECU 51 is started, and is stored in the RAM.

Next, when it is determined that the engine stop request flag is set to "ON" (S11: YES), the hybrid ECU 51 proceeds to the processing of step S15 described later. On the other hand, when it is determined that the engine stop request flag is set to "OFF" (S11: NO), the hybrid ECU 51 proceeds to the processing of step S12.

In step S12, the hybrid ECU 51 determines whether or not the engine stop requirement for stopping the diesel engine 20 is satisfied. Specifically, the hybrid ECU 51 sends an SOC request command requesting the SOC of the battery 10 to the PCU 11 and receives the SOC of the battery 10 from the PCU 11 . Next, the hybrid ECU 51 determines whether or not the SOC of the battery 10 is equal to or higher than the fully charged SOC. Here, SOC represents the remaining storage capacity, and for example, represents the ratio of the current storage capacity to the storage capacity in a fully charged state in 0 to 100 [%].

Furthermore, when receiving an SOC request command requesting transmission of the SOC of the battery 10 from the hybrid ECU 51 , the PCU 11 measures the SOC of the battery 10 and sends it to the hybrid ECU 51 . As a method of measuring the SOC executed by the PCU 11 , for example, a method by integrating current values (coulomb counting) or a method by estimating an open circuit voltage (OCV: Open Circuit Voltage) can be used.

Next, when the engine stop requirement for stopping the diesel engine 20 is not satisfied, that is, when it is determined that the SOC of the battery 10 is smaller than the charged SOC (S12: NO), the hybrid ECU 51 ends the process. On the other hand, when the engine stop requirement for stopping the diesel engine 20 is satisfied, that is, when it is determined that the SOC of the battery 10 is equal to or higher than the charged SOC (S12: YES), the hybrid ECU 51 proceeds to step S13.

In step S13, the hybrid ECU 51 transmits an engine stop request command requesting a stop of the diesel engine 20 to the engine ECU 52, and then proceeds to step S14.

Here, an example of the engine stop processing executed when the engine ECU 52 receives the engine stop request command will be described with reference to FIG. 3 . In addition, the programs shown in the flow in FIG. 3 are stored in advance in the memory bank for saving which the engine ECU 52 has. And once the engine ECU 52 is activated, it starts the processing shown in FIG. 3 every predetermined time, that is, at predetermined time intervals (for example, several millimeters to several tens of millimeters), and proceeds to step S111.

As shown in FIG. 3 , in step S111 , the engine ECU 52 determines whether or not an engine stop request command has been received. Next, when it is determined that the engine stop request command has not been received ( S111 : NO), the engine ECU 52 ends the processing. On the other hand, when it is determined that the engine stop request command has been received (S111: YES), the engine ECU 52 proceeds to step S112.

In step S112, engine ECU52 stops the fuel injection by each fuel injection valve 14A-14D, and progresses to step S113. In step S113, the engine ECU 52 outputs a control signal instructing the throttle device 47 to fully close the throttle valve 47A, and then ends the process. Thereby, the fuel injection of the diesel engine 20 is stopped, and the throttle valve 47A is fully closed.

Continue, as shown in Figure 2, in step S14, the hybrid ECU51 reads the engine stop request flag from RAM, sets it to "ON" and memorizes it into RAM again, and then proceeds to step S15. In step S15, the hybrid ECU 51 transmits a rotational speed request command requesting the rotational speed of the generating MG 32 to the PCU 11, obtains (receives) the rotational speed of the generating MG 32 from the PCU 11, stores it in the RAM sequentially, and then proceeds to step S16.

Furthermore, when the PCU 11 has received the rotational speed request command requesting the rotational speed of the MG 32 for power generation from the hybrid ECU 51 , it detects the rotational speed of the MG 32 for power generation based on the detection signal of the rotational speed of the MG 32 for power generation input from the monitoring unit 64 . Next, the PCU 11 transmits the detected rotational speed of the generating MG 32 to the hybrid ECU 51 .

Next, in step S16 , the hybrid ECU 51 calculates the rotational speed variation value (absolute value of rotational speed difference) between the current rotational speed of the power generating MG 32 and the previous power generating MG 32 rotational speed. Next, the hybrid ECU 51 determines whether the rotational speed fluctuation value of the generating MG 32 is below the first threshold value (for example, 10 to 30 [rpm] or less), that is, whether it is within a predetermined range (for example, 10 to 30 [rpm] within the range of) the speed variation value. Furthermore, the rotational speed variation value of the generating MG 32 is not limited to the rotational speed fluctuation value (rotational speed difference) between this time and the previous time, and may be an average value of the rotational speed fluctuation values (rotational speed difference) of two to five times. Furthermore, the first threshold value is stored in advance in a memory for storage included in the hybrid ECU 51 .

Next, when it is determined that the rotation speed fluctuation value of the generating MG 32 is larger than the first threshold value, that is, the compression reaction force of the diesel engine 20 is not large (S16: No), the hybrid ECU 51 proceeds to step S17. .

In step S17, the hybrid ECU 51 transmits a torque information request command requesting torque information of the generating MG 32 (rotational speed of the generating MG 32 input from the monitoring unit 64, output current value, etc.) to the PCU 11, and receives the generating MG 32 from the PCU 11. torque information. Then, based on the torque information received from the PCU 11, the hybrid ECU 51 calculates the torque of the MG 32 for power generation necessary for the engine speed of the diesel engine 20 to be the engine speed during power generation (for example, 1000~2000 [rpm]). (drive power) and stored in RAM, proceed to step S18.

Further, PCU 11 transmits torque information (rotational speed and output current value of MG 32 for power generation input from monitoring unit 64 , etc.) of MG 32 for power generation to Hybrid ECU 51 when receiving a torque information request command from Hybrid ECU 51 .

In step S18, the hybrid ECU 51 reads out the power generation necessary to make the engine speed of the diesel engine 20 equal to the engine speed (for example, 1000~2000 [rpm]) at the time of power generation, which is calculated in the aforementioned step S17 and stored in the RAM. After the torque (driving power) of the MG 32 is used and sent to the PCU 11 as the driving torque of the MG 32 for power generation, this process ends.

After this, the PCU 11 rotates and drives the generating MG 32 with the torque (driving power) of the generating MG 32 received from the hybrid ECU 51, and can control the engine speed of the diesel engine 20 to be the engine speed during power generation (e.g. , 1000~2000[rpm]).

On the other hand, in the aforementioned step S16, when it is determined that the rotational speed fluctuation value of the generating MG 32 is equal to or less than the first threshold value, that is, when the compression reaction force of the diesel engine 20 is small (S16: Yes), the hybrid ECU 51 Proceed to the processing of step S19. In step S19, the hybrid ECU 51 sends a request to the engine ECU 52 to calculate the engine intake pressure based on the detection signal input from the pressure detection device 48 corresponding to the intake pressure of the intake gas flowing into the intake manifold 45B and send it to the engine ECU 52. Inlet pressure demand command. Next, the hybrid ECU 51 memorizes the engine intake pressure acquired (received) from the engine ECU 52 in RAM, and proceeds to step S20.

Furthermore, the PCU 11 calculates the engine pressure according to the detection signal input from the pressure detection device 48 corresponding to the intake pressure of the intake gas flowing into the intake manifold 45B when the instruction of the intake pressure requirement is received from the hybrid ECU 51 . The intake air pressure is sent to the hybrid ECU51.

In step S20, the hybrid ECU 51 reads from the RAM the intake pressure of the intake manifold 45B obtained (received) in the aforementioned step S19, that is, the engine intake pressure, and determines whether it is below the third threshold (for example, 100[ Pa] below). Furthermore, the third threshold value is stored in advance in a memory for storage included in the hybrid ECU 51 .

Next, when it is determined that the intake pressure of the intake manifold 45B is greater than the third threshold, that is, the compression reaction force of the diesel engine 20 is not large (S20: No), the hybrid ECU 51 executes After the above-mentioned processing of step S17 and onwards, this processing ends.

On the other hand, when it is determined that the intake pressure of the intake manifold 45B is equal to or less than the third threshold, that is, when the compression reaction force of the diesel engine 20 is small (S20: YES), the hybrid ECU 51 advances Go to step S21. In step S21 , the hybrid ECU 51 outputs a control signal (permission to stop) instructing the regenerative drive of the generating MG 32 to the PCU 11 , and then proceeds to step S22 . After this, the diesel engine 20 is stopped by regenerative braking by the MG 32 for power generation. Next, in step S22, the hybrid ECU 51 reads the engine stop request flag from the RAM, sets it to "OFF" and stores it in the RAM again, and ends the process.

Here, timing charts for operating the power generating MG 32 and the like are shown in FIGS. 4 and 5 based on the processing procedure of the engine stop control process shown in FIG. 2 . As shown in FIG. 4 , the hybrid ECU 51 sends an engine stop request command to the engine ECU 52 at time T1 when the SOC of the battery 10 is equal to or higher than the fully charged SOC. The engine ECU 52 having received the engine stop request command stops the injection of fuel by each of the fuel injection valves 14A to 14D and fully closes the throttle valve 47A.

After that, until the rotation speed of the generating MG 32 fluctuates below the first threshold value (for example, below 10 to 30 [rpm]), and the intake pressure in the intake manifold 45B detected by the pressure detection device 48, that is, the engine Until the time T2 when the intake air pressure is lower than the third threshold (for example, 100 [kPa] or lower), the hybrid ECU 51 calculates the engine speed (for example, 1000 to 2000 [ rpm]) and the torque (drive power) of the MG32 necessary for power generation is output to the PCU11.

On the uppermost side of FIG. 4 , the variation in the rotation speed of the generating MG 32 at this time, that is, the variation in the rotation speed of the diesel engine 20 is shown in a reduced state. Furthermore, in the third counting from the top in FIG. 4 , the progress detected by the pressure detection device 48 is performed in a state where the fuel injection by the fuel injection valves 14A to 14D is stopped and the throttle valve 47A is fully closed. The decrease of the intake pressure in the air manifold 45B, that is, the intake pressure of the engine indicates that the compression reaction force of the diesel engine 20 is in a decreased state.

Next, in time T2, the rotational speed fluctuation of the generating MG 32 is equal to or less than the first threshold value (for example, equal to or less than 10 to 30 [rpm]), and the pressure When the intake pressure in the intake manifold 45B detected by the detection device 48, that is, the engine intake pressure, is below the third threshold (for example, below 100 [kPa]), the hybrid ECU 51 outputs an instruction to the PCU 11 for power generation. MG32 regenerative drive control signal (stop permission). Furthermore, during time T2, the torque fluctuation of generating MG 32 is equal to or less than the second threshold value (for example, equal to or less than 10 to 30 [Nm]).

As a result, as indicated by the solid line 71 in FIG. 5 in which the V portion of FIG. 4 is enlarged, the diesel engine 20 is regeneratively braked by the power generating MG 32, and the rotation speed decreases steadily, and almost stops at time T3. . Thereby, the vibration at the time of stop control of the diesel engine 20 can be suppressed stably. On the other hand, as indicated by the dotted line 72 in FIG. 5 , when the hybrid ECU 51 outputs a control signal (permission to stop) to the PCU 11 at a time point earlier than the time T2, which instructs the regenerative drive of the MG 32 for power generation, the Since the regenerative torque of the MG 32 for power generation is generated, the compression reaction force of the diesel engine 20 is larger, and vibration is generated during stop control of the diesel engine 20 .

Here, the diesel engine 20 series functions as one example of an internal combustion engine. The pressure detection device 48 functions as an example of an intake air pressure acquisition device. The hybrid ECU 51 functions as one example of a torque acquisition unit, a rotation fluctuation determination unit, and an intake gas pressure determination unit. The hybrid ECU51, the PCU11 and the engine ECU52 constitute a vehicle control device. The monitoring unit 64 functions as an example of a rotational speed acquisition device.

As described above in detail, in the hybrid vehicle 1 according to the first embodiment, when the diesel engine 20 is stopped by the hybrid ECU 51, the fuel injection of the fuel injection valves 14A to 14D is stopped, and the throttle valves are turned on and off. 47A is fully closed. After that, the hybrid ECU 51 waits until the variation in the rotational speed (motor generator rotational speed) of the generating MG 32 becomes less than or equal to the first threshold value, and the intake pressure of the intake manifold 45B detected by the pressure detection device 48, that is, the intake air pressure of the engine Until the air pressure becomes equal to or lower than the third threshold value, the generator MG 32 is driven so that the engine speed of the diesel engine 20 becomes the engine speed at the time of power generation.

Thus, when the variation in the rotational speed (motor generator rotational speed) of the generating MG 32 is greater than the first threshold value, or the intake pressure in the intake manifold 45B, that is, the engine intake pressure is greater than the third threshold value If it is too large, since the compression reaction force of the diesel engine 20 is not sufficiently reduced, the engine speed at the time of power generation is driven by driving the MG32 for power generation, thereby preventing a sudden drop in the engine speed and suppressing the diesel engine speed. Vibration during stop control of the engine 20.

Furthermore, when the hybrid ECU 51 stops the diesel engine 20 , it stops fuel injection from the fuel injection valves 14A to 14D and fully closes the throttle valve 47A. Thereafter, the hybrid ECU 51 is when the variation in the rotational speed (motor generator rotational speed) of the generating MG 32 is equal to or less than the first threshold and the intake pressure of the intake manifold 45B, that is, the engine intake pressure is equal to or less than the third threshold. Next, the diesel engine 20 is stopped by regeneratively driving the MG 32 for power generation.

Thus, when the variation in the rotational speed (motor generator rotational speed) of the generating MG 32 is equal to or less than the first threshold and the intake pressure of the intake manifold 45B, that is, the engine intake pressure is equal to or less than the third threshold, Di The compression reaction of the Searle engine 20 does drop. For this reason, even if the hybrid ECU51 does not have a reaction force detection device for detecting the compression reaction force of the diesel engine 20, it can stabilize and suppress the vibration during stop control of the diesel engine 20 by regeneratively driving the power generation MG32. . Furthermore, the hybrid ECU 51 can reduce the stopping speed of the diesel engine 20 by regeneratively driving the generating MG 32 , and can further stabilize and suppress the vibration during the stopping control of the diesel engine 20 .

[the second embodiment] Next, a hybrid vehicle 81 related to the second embodiment will be described based on FIGS. 4 to 6 . In addition, the same reference numerals as those of the hybrid vehicle 1 according to the above-mentioned first embodiment denote the same or equivalent parts as those of the hybrid vehicle 1 according to the above-mentioned first embodiment.

The schematic configuration and control processing of the hybrid vehicle 81 according to the second embodiment are substantially the same as the configuration and control processing of the hybrid vehicle 1 according to the first embodiment. Thus, hybrid vehicle 81 is a series hybrid vehicle. However, when the hybrid ECU 51 of the hybrid vehicle 81 stops the diesel engine 20, it executes the "second engine stop control process" shown in Fig. 6 instead of the aforementioned "engine stop control process" shown in Fig. 2 . One point is different.

One example of the second engine stop control process in which the hybrid ECU 51 stops the diesel engine 20 will be described with reference to FIG. 6 . Incidentally, the programs shown in the flow in FIG. 6 are stored in advance in the memory for storage of the hybrid ECU 51 . Then, once the hybrid ECU 51 is started, it starts the processing shown in FIG. 6 every predetermined time, that is, at predetermined time intervals (for example, several millimeters to several tens of millimeters), and proceeds to step S11.

As shown in FIG. 6 , the hybrid ECU 51 executes the processing of step S31 described later instead of the processing of step S15 after executing the processing of steps S11 to S14 of the above-mentioned "engine stop control processing" (see FIG. 2 ). Next, the hybrid ECU 51 executes a process of step S32 described later instead of the process of step S16 described above.

Specifically, in step S31, the hybrid ECU 51 sends a torque information request command requesting torque information of the power generating MG 32 (the rotational speed and output current value of the power generating MG 32 input from the monitoring unit 64) to the PCU 11, and receives it from the PCU 11. Torque information of MG32 for power generation. Then, based on the torque information received from the PCU 11, the hybrid ECU 51 calculates the torque of the MG 32 for power generation necessary for the engine speed of the diesel engine 20 to be the engine speed during power generation (for example, 1000~2000 [rpm]). (drive power). The hybrid ECU 51 memorizes the calculated torque (drive power) of the generating MG 32 in the RAM in time series, and proceeds to step S32.

Further, PCU 11 transmits torque information (rotational speed and output current value of MG 32 for power generation input from monitoring unit 64 , etc.) of MG 32 for power generation to Hybrid ECU 51 when receiving a torque information request command from Hybrid ECU 51 .

Next, in step S32 , the hybrid ECU 51 calculates the torque fluctuation value (absolute value of torque difference) between the torque of the current generating MG 32 and the previous torque of the generating MG 32 . Next, the hybrid ECU 51 determines whether the torque fluctuation value of the generating MG 32 is equal to or less than the second threshold value (for example, 10 to 30 [Nm] or less), that is, whether it is within a predetermined range (for example, 10 to 30 [Nm] range) torque variation value. Furthermore, the torque fluctuation value of the generating MG 32 is not limited to the torque fluctuation value (torque difference) between this time and the previous time, and may be an average value of torque fluctuation values (torque difference) such as 2 to 5 times. Furthermore, the second threshold value is stored in advance in a memory for storage included in the hybrid ECU 51 .

Next, when it is determined that the torque fluctuation value of the generating MG 32 is larger than the second threshold value, that is, the compression reaction force of the diesel engine 20 is not large (S32: No), the hybrid ECU 51 replaces the above steps. The processing of S17 and step S18 executes the processing of step S33. In step S33, the hybrid ECU 51 reads out the power generation necessary to make the engine speed of the diesel engine 20 equal to the engine speed (for example, 1000~2000 [rpm]) at the time of power generation, which was calculated in the aforementioned step S31 and stored in the RAM. After the torque (driving power) of the MG 32 is used and sent to the PCU 11 as the driving torque of the MG 32 for power generation, this process ends.

After this, the PCU 11 rotates and drives the generating MG 32 with the torque (driving power) of the generating MG 32 received from the hybrid ECU 51, and can control the engine speed of the diesel engine 20 to be the engine speed during power generation (e.g. , 1000~2000[rpm]).

On the other hand, when it is determined that the torque variation value of the generating MG 32 is equal to or less than the second threshold value, that is, the compression reaction force of the diesel engine 20 is small (S32: Yes), the hybrid ECU 51 proceeds to the aforementioned step. The processing of S19 executes the processing of the aforementioned steps S19 and S20. Next, when it is determined that the intake pressure of the intake manifold 45B is greater than the third threshold, that is, the compression reaction force of the diesel engine 20 is not large (S20: No), the hybrid ECU 51 executes After the above-mentioned processing of step S33 is completed, this processing ends.

On the other hand, when it is determined that the intake pressure of the intake manifold 45B is equal to or less than the third threshold, that is, when the compression reaction force of the diesel engine 20 is small (S20: Yes), the hybrid ECU 51 After the above-mentioned processing of step S21 and step S22 is performed, this processing ends. After this, the diesel engine 20 is stopped by regenerative braking by the MG 32 for power generation.

Here, timing charts for operating the power generating MG 32 and the like are shown in FIGS. 4 and 5 based on the processing procedure of the second engine stop control process shown in FIG. 6 . As shown in FIG. 4 , the hybrid ECU 51 sends an engine stop request command to the engine ECU 52 at time T1 when the SOC of the battery 10 is equal to or higher than the fully charged SOC. The engine ECU 52 having received the engine stop request command stops the injection of fuel by each of the fuel injection valves 14A to 14D and fully closes the throttle valve 47A.

Thereafter, until the torque fluctuation of the generating MG 32 becomes below the second threshold value (for example, below 10 to 30 [Nm]), and the intake pressure in the intake manifold 45B detected by the pressure detecting device 48, that is, the engine Until time T2 when the intake air pressure is below the third threshold (for example, below 100 [Pa]), the hybrid ECU 51 calculates the engine speed (for example, 1000 to 2000 [ rpm]) and the torque (drive power) of the MG32 necessary for power generation is output to the PCU11.

In the third counting from the top of FIG. 4 , the intake manifold detected by the pressure detection device 48 is in a state where the fuel injection by the fuel injection valves 14A to 14D is stopped and the throttle valve 47A is fully closed. The decrease in the intake pressure in the pipe 45B, that is, the engine intake pressure indicates that the compression reaction force of the diesel engine 20 is in a decreased state. Furthermore, the fourth one from the top of FIG. 4 shows that the variation of the torque of the generating MG 32 at this time is in a reduced state.

Next, at time T2, the moment fluctuation in the generating MG 32 is equal to or less than the second threshold value (for example, equal to or less than 10 to 30 [Nm]), and the intake pressure in the intake manifold 45B detected by the pressure detection device 48 That is, when the intake air pressure of the engine is lower than the third threshold (for example, lower than 100 [Pa]), the hybrid ECU 51 outputs a control signal (permission to stop) to the PCU 11 for regenerative driving of the MG 32 for power generation. Furthermore, during time T2, the rotational speed fluctuation of generating MG 32 is equal to or less than the first threshold value (for example, equal to or less than 10 to 30 [rpm]).

As a result, as indicated by the solid line 71 in FIG. 5 in which the V portion of FIG. 4 is enlarged, the diesel engine 20 is regeneratively braked by the power generating MG 32, and the rotation speed decreases steadily, and almost stops at time T3. . Thereby, the vibration at the time of stop control of the diesel engine 20 can be suppressed stably. On the other hand, as indicated by the dotted line 72 in FIG. 5 , when the hybrid ECU 51 outputs a control signal (permission to stop) to the PCU 11 at a time point earlier than the time T2, which instructs the regenerative drive of the MG 32 for power generation, the Since the regenerative torque of the MG 32 for power generation is generated, the compression reaction force of the diesel engine 20 is larger, and vibration is generated during stop control of the diesel engine 20 .

Here, the diesel engine 20 series functions as one example of an internal combustion engine. The pressure detection device 48 functions as an example of an intake air pressure acquisition device. The hybrid ECU 51 functions as an example of a torque acquisition unit, a torque fluctuation determination unit, and an intake gas pressure determination unit. The hybrid ECU51, the PCU11 and the engine ECU52 constitute a vehicle control device.

As described above in detail, in the hybrid vehicle 81 according to the second embodiment, when the diesel engine 20 is stopped by the hybrid ECU 51, the fuel injection of the fuel injection valves 14A to 14D is stopped, and the throttle valves are turned on and off. 47A is fully closed. Thereafter, the hybrid ECU 51 waits until the torque fluctuation of the generating MG 32 becomes lower than the second threshold value, and the intake pressure of the intake manifold 45B, that is, the engine intake pressure detected by the pressure detection device 48 becomes lower than the third threshold value. So far, the MG 32 for power generation is driven so that the engine speed of the diesel engine 20 becomes the engine speed during power generation.

Thus, when the torque fluctuation of the generating MG 32 is larger than the second threshold value, or when the intake pressure of the intake manifold 45B, that is, the engine intake pressure is larger than the third threshold value, Di Since the compression reaction force of the Searle engine 20 does not decrease sufficiently, the engine speed at the time of power generation is driven by driving the MG32 for power generation, thereby preventing a sudden drop in the engine speed and suppressing the stoppage of the diesel engine 20. vibration.

Furthermore, when the hybrid ECU 51 stops the diesel engine 20 , it stops fuel injection from the fuel injection valves 14A to 14D and fully closes the throttle valve 47A. Thereafter, the hybrid ECU 51 regenerates the MG 32 for power generation when the torque fluctuation of MG 32 for power generation is equal to or less than the second threshold and the intake pressure of the intake manifold 45B, that is, the intake air pressure of the engine is equal to or less than the third threshold. The diesel engine 20 is driven to stop.

Thus, when the torque variation of the generating MG 32 is equal to or less than the second threshold and the intake pressure of the intake manifold 45B, that is, the engine intake pressure is equal to or less than the third threshold, the compression reaction of the diesel engine 20 Force does drop. For this reason, even if the hybrid ECU51 does not have a reaction force detection device for detecting the compression reaction force of the diesel engine 20, it can stabilize and suppress the vibration during stop control of the diesel engine 20 by regeneratively driving the power generation MG32. . Furthermore, the hybrid ECU 51 can reduce the stopping speed of the diesel engine 20 by regeneratively driving the generating MG 32 , and can further stabilize and suppress the vibration during the stopping control of the diesel engine 20 .

[the third embodiment] Next, a hybrid vehicle 91 related to the third embodiment will be described based on FIG. 4 , FIG. 5 and FIG. 7 . In addition, the same reference numerals as those of the hybrid vehicle 1 according to the above-mentioned first embodiment denote the same or equivalent parts as those of the hybrid vehicle 1 according to the above-mentioned first embodiment.

The schematic configuration and control processing of the hybrid vehicle 91 according to the third embodiment are substantially the same as the configuration and control processing of the hybrid vehicle 1 according to the first embodiment. Thus, hybrid vehicle 91 is a series hybrid vehicle. However, when the hybrid ECU 51 of the hybrid vehicle 91 stops the diesel engine 20, it executes the "third engine stop control process" shown in Fig. 7 instead of the aforementioned "engine stop control process" shown in Fig. 2 . One point is different.

One example of the third engine stop control process in which the hybrid ECU 51 stops the diesel engine 20 will be described with reference to FIG. 7 . Incidentally, the programs shown in the flow in FIG. 7 are stored in advance in the memory for storage of the hybrid ECU 51 . Then, once the hybrid ECU 51 is started, it starts the processing shown in FIG. 7 every predetermined time, that is, at predetermined time intervals (for example, several millimeters to several tens of millimeters), and proceeds to step S11.

As shown in FIG. 7, the hybrid ECU 51 executes the above-mentioned "second engine stop control process" (see Fig. 6) The processing of step S31 to step S32. Next, when it is determined that the torque fluctuation value of the generating MG 32 is larger than the second threshold value, that is, the compression reaction force of the diesel engine 20 is not large (S32: No), the hybrid ECU 51 replaces the above steps. The processing of S17 and step S18 ends after the processing of step S33 of the above-mentioned "second engine stop control processing" (refer to FIG. 6 ) is executed.

On the other hand, when it is determined that the torque fluctuation value of the generating MG 32 is equal to or less than the second threshold value, that is, the compression reaction force of the diesel engine 20 is small (S32: YES), the hybrid ECU 51 executes the above-mentioned "Engine stop control process" (refer to FIG. 2 ) After the aforementioned steps S15 to S22, this process ends.

However, in step S16, when it is determined that the rotational speed fluctuation value of the generating MG 32 is larger than the first threshold value, that is, the compression reaction force of the diesel engine 20 is not large (S16: NO), the hybrid ECU 51 After the processing of step S33 of the above-mentioned "second engine stop control processing" (refer to FIG. 6 ) is executed instead of the processing of step S17 and step S18, the processing ends. And, in step S20, when it is determined that the intake pressure of the intake manifold 45B is higher than the third threshold value, that is, the compression reaction force of the diesel engine 20 is not large (S20: No), the mixed The power ECU 51 executes the processing of step S33 of the above-mentioned "second engine stop control processing" (see FIG. 6 ) instead of the processing of the above-mentioned steps S17 and S18, and ends the processing.

Here, timing charts for operating the power generating MG 32 and the like are shown in FIGS. 4 and 5 based on the processing procedure of the third engine stop control process shown in FIG. 7 . As shown in FIG. 4 , the hybrid ECU 51 sends an engine stop request command to the engine ECU 52 at time T1 when the SOC of the battery 10 is equal to or higher than the fully charged SOC. The engine ECU 52 having received the engine stop request command stops the injection of fuel by each of the fuel injection valves 14A to 14D and fully closes the throttle valve 47A.

Thereafter, until the rotation speed variation of the generating MG32 is below the first threshold (for example, 10 to 30 [rpm] or less), and the torque variation of the generating MG32 is below the second threshold (for example, 10 to 30 [Nm] or less) ), further, until the time T2 when the intake pressure in the intake manifold 45B detected by the pressure detection device 48, that is, the engine intake pressure is below the third threshold (for example, below 100 [Pa]), the hybrid The ECU 51 calculates the torque (driving power) of the generating MG 32 necessary to make the engine speed of the diesel engine 20 equal to the engine speed during power generation (for example, 1000 to 2000 [rpm]), and outputs it to the PCU 11 .

On the uppermost side of FIG. 4 , the variation in the rotation speed of the generating MG 32 at this time, that is, the variation in the rotation speed of the diesel engine 20 is shown in a reduced state. Furthermore, in the third counting from the top in FIG. 4 , the progress detected by the pressure detection device 48 is performed in a state where the fuel injection by the fuel injection valves 14A to 14D is stopped and the throttle valve 47A is fully closed. The decrease of the intake pressure in the air manifold 45B, that is, the intake pressure of the engine indicates that the compression reaction force of the diesel engine 20 is in a decreased state. Furthermore, the fourth one from the top of FIG. 4 shows that the variation of the torque of the generating MG 32 at this time is in a reduced state.

Next, in time T2, the rotational speed variation of the generating MG 32 is below the first threshold (for example, 10 to 30 [rpm] or less), and the torque variation of the generating MG 32 is below the second threshold (for example, 10 to 30[rpm]). Nm] or less), further, when the intake pressure in the intake manifold 45B detected by the pressure detection device 48, that is, the engine intake pressure is below the third threshold (for example, below 100 [Pa]), the hybrid The ECU 51 outputs a control signal (permission to stop) for instructing the regenerative drive of the MG 32 for power generation to the PCU 11 .

As a result, as indicated by the solid line 71 in FIG. 5 in which the V portion of FIG. 4 is enlarged, the diesel engine 20 is regeneratively braked by the power generating MG 32, and the rotation speed decreases steadily, and almost stops at time T3. . Thereby, the vibration at the time of stop control of the diesel engine 20 can be suppressed stably. On the other hand, as indicated by the dotted line 72 in FIG. 5 , when the hybrid ECU 51 outputs a control signal (permission to stop) to the PCU 11 at a time point earlier than the time T2, which instructs the regenerative drive of the MG 32 for power generation, the Since the regenerative torque of the MG 32 for power generation is generated, the compression reaction force of the diesel engine 20 is larger, and vibration is generated during stop control of the diesel engine 20 .

Here, the diesel engine 20 series functions as one example of an internal combustion engine. The pressure detection device 48 functions as an example of an intake air pressure acquisition device. The hybrid ECU 51 functions as an example of a torque acquisition unit, a rotation fluctuation determination unit, a torque fluctuation determination unit, and an intake gas pressure determination unit. The hybrid ECU51, the PCU11 and the engine ECU52 constitute a vehicle control device. The monitoring unit 64 functions as an example of a rotational speed acquisition device.

As described above in detail, in the hybrid vehicle 91 according to the third embodiment, when the diesel engine 20 is stopped by the hybrid ECU 51, the fuel injection of each fuel injection valve 14A to 14D is stopped, and the throttle valve is turned on. 47A is fully closed. Thereafter, the hybrid ECU 51 is detected by the pressure detection device 48 until the variation in the rotational speed (motor generator rotational speed) of the MG 32 for power generation becomes less than or equal to the first threshold value, and the torque fluctuation of the MG 32 for power generation becomes less than or equal to the second threshold value. Until the intake pressure of the intake manifold 45B, that is, the engine intake pressure becomes lower than the third threshold value, the generator MG 32 is driven so that the engine speed of the diesel engine 20 becomes the engine speed for power generation.

Accordingly, when the variation in the rotation speed (motor generator rotation speed) of the generating MG 32 is larger than the first threshold, or when the torque variation of the generating MG 32 is larger than the second threshold, or, When the intake pressure of the intake manifold 45B, that is, the engine intake pressure is higher than the third threshold value, the compression reaction force of the diesel engine 20 cannot be sufficiently reduced, and the MG 32 for power generation is driven to generate power. This prevents a rapid drop in the engine speed and suppresses vibration during stop control of the diesel engine 20 .

Furthermore, when the hybrid ECU 51 stops the diesel engine 20 , it stops fuel injection from the fuel injection valves 14A to 14D and fully closes the throttle valve 47A. Thereafter, the hybrid ECU 51 performs a change in the rotational speed (motor generator rotational speed) of the generating MG 32 below the first threshold and a torque fluctuation of the generating MG 32 below the second threshold. When the gas pressure, that is, the engine intake pressure is equal to or less than the third threshold value, the generator MG 32 is regeneratively driven to stop the diesel engine 20 .

As a result, when the variation in the rotational speed (motor generator rotational speed) of MG 32 for power generation is equal to or less than the first threshold value, and the torque fluctuation of MG 32 for power generation is equal to or less than the second threshold value, furthermore, the intake pressure of intake manifold 45B is also equal to or lower than the second threshold value. That is, when the engine intake pressure is equal to or less than the third threshold, the compression reaction force of the diesel engine 20 is surely reduced. For this reason, even if the hybrid ECU51 does not have a reaction force detection device for detecting the compression reaction force of the diesel engine 20, it can stabilize and suppress the vibration during stop control of the diesel engine 20 by regeneratively driving the power generation MG32. . Furthermore, the hybrid ECU 51 can reduce the stopping speed of the diesel engine 20 by regeneratively driving the generating MG 32 , and can further stabilize and suppress the vibration during the stopping control of the diesel engine 20 .

Also, the present invention is not limited to the aforementioned first to third embodiments, and various improvements, modifications, additions, and deletions are of course possible without departing from the gist of the present invention. For example, it may be as follows. Furthermore, in the following description, the same reference numerals as those of the hybrid vehicle 1 and the like according to the first embodiment described above in FIGS. .

[another first embodiment] (A) For example, in the hybrid vehicle 1 related to the aforementioned first embodiment, when the hybrid ECU 51 executes the aforementioned "engine stop control process" shown in FIG. deal with. Specifically, in step S16, when it is determined that the rotational speed variation value of the generating MG 32 is below the first threshold, that is, when the compression reaction force of the diesel engine 20 is small (S16: Yes), the hybrid The ECU 51 proceeds to the processing of step S21. Next, the hybrid ECU 51 may end the processing after executing the processing of steps S21 to S22.

For example, as shown in FIG. 4 , when the variation in the rotational speed (motor generator rotational speed) of MG 32 for power generation is less than or equal to a first threshold value during time T2, hybrid ECU 51 may output an instruction to PCU 11 for regenerative driving of MG 32 for power generation. Control signal (stop permission). As a result, as indicated by the solid line 71 in FIG. 5 in which the V portion of FIG. 4 is enlarged, the diesel engine 20 is regeneratively braked by the power generating MG 32, and the rotation speed decreases steadily, and almost stops at time T3. . Thereby, the vibration at the time of stop control of the diesel engine 20 can be suppressed stably.

Here, the diesel engine 20 series functions as one example of an internal combustion engine. The hybrid ECU 51 functions as an example of a torque acquisition unit and a rotation fluctuation determination unit. The hybrid ECU51, the PCU11 and the engine ECU52 constitute a vehicle control device. The monitoring unit 64 functions as an example of a rotational speed acquisition device.

Therefore, in the hybrid vehicle 1 configured in this way, the hybrid ECU 51 stops fuel injection from the fuel injection valves 14A to 14D and fully closes the throttle valve 47A when stopping the diesel engine 20 . Thereafter, the hybrid ECU 51 drives the generator MG 32 until the variation in the rotation speed (motor generator rotation speed) of the generator MG 32 becomes below the first threshold value so that the engine rotation speed of the Diesel engine 20 becomes the engine rotation speed during power generation.

Thus, when the variation in the rotational speed (motor generator rotational speed) of MG 32 for power generation is greater than the first threshold value, since the compression reaction force of diesel engine 20 does not sufficiently decrease, MG 32 for power generation is driven to generate power. By doing this, a sudden drop in the engine speed can be prevented, and vibration during stop control of the diesel engine 20 can be suppressed.

Furthermore, when the hybrid ECU 51 stops the diesel engine 20 , it stops fuel injection from the fuel injection valves 14A to 14D and fully closes the throttle valve 47A. Thereafter, the hybrid ECU 51 regeneratively drives the generating MG 32 to stop the diesel engine 20 when the variation in the rotation speed (motor generator rotation speed) of the generating MG 32 is equal to or less than a first threshold value.

As a result, when the variation in the rotation speed (motor generator rotation speed) of the generating MG 32 is equal to or less than the first threshold value, the compression reaction force of the diesel engine 20 is reliably reduced. For this reason, even if the hybrid ECU51 does not have a reaction force detection device for detecting the compression reaction force of the diesel engine 20, it can stabilize and suppress the vibration during stop control of the diesel engine 20 by regeneratively driving the power generation MG32. . Furthermore, the hybrid ECU 51 can reduce the stopping speed of the diesel engine 20 by regeneratively driving the generating MG 32 , and can further stabilize and suppress the vibration during the stopping control of the diesel engine 20 .

[another second embodiment] (B) Furthermore, for example, in the hybrid vehicle 81 related to the aforementioned second embodiment, when the hybrid ECU 51 executes the aforementioned "second engine stop control process" shown in FIG. 6 , step S19 may not be executed. ~ the processing of step S20. Specifically, in step S32, when the torque fluctuation value of the generating MG 32 is equal to or less than the second threshold value, that is, when the compression reaction force of the diesel engine 20 is small (S32: Yes), the hybrid ECU 51 may move forward. The process proceeds to step S21. Next, the hybrid ECU 51 may end the processing after executing the processing of steps S21 to S22.

For example, as shown in FIG. 4 , when the torque fluctuation of MG 32 for power generation falls below the second threshold value during time T2, hybrid ECU 51 may output a control signal (permission to stop) to PCU 11 for regenerative driving of MG 32 for power generation. As a result, as indicated by the solid line 71 in FIG. 5 in which the V portion of FIG. 4 is enlarged, the diesel engine 20 is regeneratively braked by the power generating MG 32, and the rotation speed decreases steadily, and almost stops at time T3. . Thereby, the vibration at the time of stop control of the diesel engine 20 can be suppressed stably.

Here, the diesel engine 20 series functions as one example of an internal combustion engine. The hybrid ECU 51 functions as an example of a torque acquisition unit and a torque fluctuation determination unit. The hybrid ECU51, the PCU11 and the engine ECU52 constitute a vehicle control device.

Therefore, in the hybrid vehicle 81 configured in this way, when the diesel engine 20 is stopped, the hybrid ECU 51 stops fuel injection from the fuel injection valves 14A to 14D and fully closes the throttle valve 47A. Thereafter, the hybrid ECU 51 drives the generator MG 32 until the torque fluctuation of the generator MG 32 becomes equal to or less than the second threshold value so that the engine speed of the diesel engine 20 becomes the engine speed during power generation.

Thus, when the torque fluctuation of the generating MG 32 is larger than the second threshold value, the compression reaction force of the diesel engine 20 cannot be sufficiently reduced, and the generating MG 32 is driven to the engine speed for generating power. , it is possible to prevent a sudden drop in the engine rotational speed, and it is possible to suppress vibration during stop control of the diesel engine 20 .

Furthermore, when the hybrid ECU 51 stops the diesel engine 20 , it stops fuel injection from the fuel injection valves 14A to 14D and fully closes the throttle valve 47A. Thereafter, the hybrid ECU 51 regeneratively drives the generating MG 32 to stop the diesel engine 20 when the torque variation of the generating MG 32 is equal to or less than the second threshold value.

As a result, when the torque fluctuation of the generating MG 32 is equal to or less than the second threshold value, the compression reaction force of the diesel engine 20 is reliably reduced. For this reason, even if the hybrid ECU51 does not have a reaction force detection device for detecting the compression reaction force of the diesel engine 20, it can stabilize and suppress the vibration during stop control of the diesel engine 20 by regeneratively driving the power generation MG32. . Furthermore, the hybrid ECU 51 can reduce the stopping speed of the diesel engine 20 by regeneratively driving the generating MG 32 , and can further stabilize and suppress the vibration during the stopping control of the diesel engine 20 .

[another third embodiment] (C) Furthermore, for example, in the hybrid vehicle 91 related to the aforementioned third embodiment, when the hybrid ECU 51 executes the aforementioned "third engine stop control process" shown in FIG. 7, step S19 may not be executed. ~ the processing of step S20. Specifically, in step S16, when it is determined that the rotational speed variation value of the generating MG 32 is below the first threshold, that is, when the compression reaction force of the diesel engine 20 is small (S16: Yes), the hybrid The ECU 51 proceeds to the processing of step S21. Next, the hybrid ECU 51 may end the processing after executing the processing of steps S21 to S22.

For example, as shown in FIG. 4 , when the variation in the rotation speed (motor generator rotation speed) of MG 32 for power generation is equal to or less than a first threshold and the variation in torque of MG 32 for power generation is equal to or less than a second threshold value during time T2, the hybrid power The ECU 51 outputs a control signal (permission to stop) for instructing the regenerative drive of the MG 32 for power generation to the PCU 11 . As a result, as indicated by the solid line 71 in FIG. 5 in which the V portion of FIG. 4 is enlarged, the diesel engine 20 is regeneratively braked by the power generating MG 32, and the rotation speed decreases steadily, and almost stops at time T3. . Thereby, the vibration at the time of stop control of the diesel engine 20 can be suppressed stably.

Here, the diesel engine 20 series functions as one example of an internal combustion engine. The hybrid ECU 51 functions as one example of a torque acquisition unit, a rotation fluctuation determination unit, and a torque fluctuation determination unit. The hybrid ECU51, the PCU11 and the engine ECU52 constitute a vehicle control device. The monitoring unit 64 functions as an example of a rotational speed acquisition device.

Therefore, in the hybrid vehicle 1 configured in this way, the hybrid ECU 51 stops fuel injection from the fuel injection valves 14A to 14D and fully closes the throttle valve 47A when stopping the diesel engine 20 . After that, the hybrid ECU 51 waits until the variation in the rotation speed (motor generator rotation speed) of the generating MG 32 becomes below the first threshold value, and the torque variation of the generating MG 32 becomes below the second threshold value, in order to make the diesel engine 20 The engine speed becomes the engine speed at the time of power generation, and the MG32 for power generation is driven.

Thus, when the variation in the rotational speed (motor generator rotational speed) of MG 32 for power generation is greater than the first threshold value, or when the torque fluctuation of MG 32 for power generation is greater than the second threshold value, the diesel engine Since the compression reaction force of the diesel engine 20 does not decrease sufficiently, the engine rotation speed during power generation is driven by driving the generating MG 32 , thereby preventing a rapid drop in the engine rotation speed and suppressing vibration during stop control of the diesel engine 20 .

Furthermore, when the hybrid ECU 51 stops the diesel engine 20 , it stops fuel injection from the fuel injection valves 14A to 14D and fully closes the throttle valve 47A. Thereafter, the hybrid ECU 51 regeneratively drives the generating MG 32 when the variation in the rotation speed (motor generator rotation speed) of the generating MG 32 is equal to or less than the first threshold and the torque variation of the generating MG 32 is equal to or less than the second threshold. The diesel engine 20 is stopped.

As a result, when the variation in the rotation speed (motor generator rotation speed) of the generating MG 32 is equal to or less than the first threshold, and the torque variation of the generating MG 32 is equal to or less than the second threshold, the compression reaction force of the diesel engine 20 is assured. decline. For this reason, even if the hybrid ECU51 does not have a reaction force detection device for detecting the compression reaction force of the diesel engine 20, it can stabilize and suppress the vibration during stop control of the diesel engine 20 by regeneratively driving the power generation MG32. . Moreover, the hybrid ECU51 generates power by generating By using MG32 regenerative drive, the stop speed of the diesel engine 20 can be reduced, and the vibration during stop control of the diesel engine 20 can be further stabilized and suppressed.

(D) Furthermore, for example, in the hybrid vehicle 1 according to the first embodiment described above, the diesel engine 20 may be used as an example of the internal combustion engine, but a gasoline engine may also be used.

(E) Furthermore, for example, in the hybrid vehicle 1 related to the above-mentioned first embodiment, the pressure detection device 48 may be configured so that the intake air pressure corresponding to the intake gas flowing into the intake manifold 45B just before The detection signal is output to the hybrid ECU51 and the engine ECU52. This can suppress the influence of the communication delay between the hybrid ECU 51 and the engine ECU 52 on the acquisition of the intake pressure of the intake manifold 45B by the hybrid ECU 51 .

(F) The numerical values used in the description of the first embodiment to the third embodiment are examples, and are not limited thereto. Furthermore, the above (≧), below (≦), greater than (>), less than (<) and the like may or may not contain an equal sign.

1, 81, 91: hybrid vehicles

10: battery

11: Power Control Unit (PCU)

14A~14D: fuel injection valve

20: Diesel engine

31: Motor generator for driving (MG for driving)

32: Motor generator for power generation (MG for power generation)

40: Drive wheel

45A: Intake pipe

45B: intake manifold

47A: throttle valve

48: Pressure detection device

51: Hybrid ECU

52:Engine ECU

61~64: Monitoring unit

21: axis of rotation

22: Rotation axis

23: gear

41: axis of rotation

42: drive shaft

43: Power transmission gear

47: Throttle device

65: Throttle opening sensor

66: Vehicle speed sensor

13A~13D: Cylinder

20A: Engine body

46A: exhaust pipe

46B: exhaust manifold

47S: Throttle opening detection device

[ Fig. 1 ] is a diagram illustrating a schematic configuration of a hybrid vehicle according to a first embodiment. [ Fig. 2 ] is a flowchart showing an example of engine stop control processing executed by the hybrid ECU. [ Fig. 3 ] is a flowchart showing an example of engine stop processing executed by the engine ECU. [ Fig. 4] Fig. 4 is a time chart showing an example of the operation of a power generating motor generator and the like when the internal combustion engine is stopped. [ Fig. 5 ] is an enlarged view of a V portion in Fig. 4 . [ Fig. 6 ] is a flowchart showing an example of the second engine stop control process executed by the hybrid ECU according to the second embodiment. [ Fig. 7 ] is a flowchart showing an example of third engine stop control processing executed by the hybrid ECU according to the third embodiment.

1,81,91: Hybrid vehicles

10: battery

11: Power Control Unit (PCU)

13A~13D: Cylinder

14A~14D: fuel injection valve

20: Diesel engine

20A: Engine body

21,22: axis of rotation

23: gear

31: Motor generator for driving (MG for driving)

32: Motor generator for power generation (MG for power generation)

40: Drive wheel

41: axis of rotation

42: drive shaft

43: Power transmission gear

45A: Intake pipe

45B: intake manifold

46A: Connect the exhaust pipe

46B: exhaust manifold

47: Throttle device

47A: throttle valve

48: Pressure detection device

51: Hybrid ECU

52:Engine ECU

61~64: Monitoring unit

65: Throttle opening sensor

66: Vehicle speed sensor

Claims (4)

A hybrid vehicle having: internal combustion engine; A motor generator for power generation, which is connected to the aforementioned internal combustion engine; A battery charged via the aforementioned motor generator for power generation; A motor generator for driving, which drives the drive wheels using the discharged electric power of the aforementioned battery; a rotational speed acquisition device, which acquires the rotational speed of the motor generator of the aforementioned motor generator for power generation; and A vehicle control device that controls the aforementioned internal combustion engine, the aforementioned motor generator for power generation, and the aforementioned motor generator for driving; in, The aforementioned internal combustion engine has: an intake pipe connected to the upstream side of the intake manifold; a throttle valve, which can adjust the opening degree of the aforementioned intake pipe; and a plurality of fuel injection valves for injecting fuel into each cylinder of the aforementioned internal combustion engine; The vehicle control device includes a torque acquisition unit and a rotation fluctuation determination unit, wherein When stopping the internal combustion engine, after stopping fuel injection by the plurality of fuel injection valves and fully closing the throttle valve, The torque obtaining unit obtains the torque of the electric generator for power generation necessary for the internal combustion engine to attain the engine speed for power generation every predetermined time, and The rotation fluctuation determination unit determines whether the rotation speed fluctuation of the motor generator is less than or equal to a predetermined first threshold every predetermined time; The aforementioned vehicle control device is When it is determined by the rotation fluctuation determination unit that the rotation speed fluctuation of the motor generator rotation speed is larger than the first threshold value, control to drive the power generation motor generator with the torque; When it is determined by the rotation fluctuation determination unit that the rotation speed fluctuation of the motor generator is equal to or less than the first threshold value, the internal combustion engine is controlled to be stopped using the power generating motor generator. A hybrid vehicle having: internal combustion engine; A motor generator for power generation, which is connected to the aforementioned internal combustion engine; A battery charged via the aforementioned motor generator for power generation; A motor generator for driving, which drives the drive wheels using the discharged electric power of the aforementioned battery; A vehicle control device that controls the aforementioned internal combustion engine, the aforementioned motor generator for power generation, and the aforementioned motor generator for driving; in, The aforementioned internal combustion engine has: an intake pipe connected to the upstream side of the intake manifold; a throttle valve, which can adjust the opening degree of the aforementioned intake pipe; and a plurality of fuel injection valves for injecting fuel into each cylinder of the aforementioned internal combustion engine; The vehicle control device includes a torque acquisition unit and a torque fluctuation determination unit, wherein When stopping the internal combustion engine, after stopping fuel injection by the plurality of fuel injection valves and fully closing the throttle valve, The torque obtaining unit obtains the torque of the electric generator for power generation necessary for the internal combustion engine to attain the engine speed for power generation every predetermined time, and The torque variation determination unit determines whether the torque variation of the torque acquired through the torque acquisition unit is equal to or less than a predetermined second threshold value; The aforementioned vehicle control device is When it is determined by the torque fluctuation determining unit that the torque fluctuation of the torque is larger than the second threshold value, control to drive the generating motor generator with the torque; When it is determined by the torque fluctuation determination unit that the torque fluctuation of the torque is equal to or less than the second threshold value, the internal combustion engine is controlled to be stopped using the power generating motor generator. Such as the hybrid vehicle of claim 1 or claim 2, wherein, It also has an intake pressure obtaining device for obtaining the intake pressure of the aforementioned intake manifold; The vehicle control device includes an intake air pressure determination unit that determines whether the intake air pressure of the intake manifold is equal to or less than a predetermined third threshold every predetermined time; The aforementioned vehicle control device is When the internal combustion engine is stopped, after the fuel injection by the plurality of fuel injection valves is stopped and the throttle valve is fully closed, furthermore, after the intake gas pressure determination unit determines that the intake manifold When the intake air pressure is equal to or less than the third threshold value, control is performed to stop the internal combustion engine using the power generating motor generator. Such as the hybrid vehicle of claim 1 or claim 2, wherein, The aforementioned vehicle control device is When the internal combustion engine is stopped using the electric generating motor generator, the electric generating motor generator is controlled to be regeneratively driven.

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