JP2020069950A - Hybrid automobile - Google Patents

Abstract

To suppress lengthening of time required for completing regeneration of a filter when the filter requires to be regenerated.SOLUTION: A preparation process of decreasing a charge ratio of a battery is performed to decrease a charge ratio of a battery when an accumulated amount of particulate materials accumulated on a filter reaches or exceeds a predetermined amount (i.e., necessary to regenerate ), and a filter regeneration process for regenerating the filer is performed with low load operation of an engine when the charge ratio of the battery reaches a predetermined ratio or less. Thus, necessity to limit the high-load operation of the engine in order to suppress overcharge of a battery can be suppressed. As a result, lengthening of time required for reaching of the temperature of the filter to temperature suitable for regeneration is suppressed and lengthening of time required to completion of the regeneration of the filter can be suppressed.SELECTED DRAWING: Figure 2

Description

  TECHNICAL FIELD The present invention relates to a hybrid vehicle, and more particularly, to a hybrid vehicle including an engine in which a filter for removing particulate matter is attached to an exhaust system.

  Conventionally, as a hybrid vehicle of this type, an engine in which a filter for removing particulate matter is attached to an exhaust system, a generator that generates power by using power from the engine, a running motor, a generator and a motor It has been proposed to provide a battery that exchanges electric power with a cooling fan and a cooling fan that cools the battery, and to perform a filter regeneration process that regenerates the filter along with high load operation of the engine when the filter needs to be regenerated. (For example, refer to Patent Document 1). In this hybrid vehicle, when the filter regeneration process is executed, the cooling fan is driven prior to the execution of the filter regeneration process to suppress the temperature rise of the battery due to the charging of the battery due to the high load operation of the engine in the filter regeneration process. The input limit is suppressed from becoming small. As a result, it is possible to prevent the high load operation of the engine from being continued because the input limit of the battery becomes small, and it is possible to prevent the temperature of the filter from quickly reaching the temperature suitable for regeneration.

JP, 2017-132299, A

  In the above-described hybrid vehicle, in the filter regeneration process, when the charge ratio of the battery is high, the time required for the temperature of the filter to reach a temperature suitable for regeneration cannot be achieved because the engine cannot be sufficiently operated under high load. May become longer and the time required to complete the regeneration of the filter may become longer.

  The main purpose of the hybrid vehicle of the present invention is to suppress an increase in the time required to complete the regeneration of the filter when the regeneration of the filter is required.

  The hybrid vehicle of the present invention employs the following means in order to achieve the above-mentioned main object.

The hybrid vehicle of the present invention is
An engine with a filter attached to the exhaust system to remove particulate matter,
A generator capable of generating power using power from the engine,
A motor for traveling,
A power storage device that exchanges electric power with the generator and the motor;
A control device for controlling the engine, the generator, and the motor;
A hybrid vehicle comprising:
When the amount of particulate matter deposited on the filter reaches a predetermined amount or more, the control device executes a preparatory process for reducing the power storage ratio of the power storage device, and the power storage ratio of the power storage device is equal to or lower than a predetermined ratio. When it reaches, to perform a filter regeneration process of regenerating the filter with high load operation of the engine,
That is the summary.

  In this hybrid vehicle of the present invention, when the amount of particulate matter deposited on the filter reaches a predetermined amount or more (when the filter needs to be regenerated), a preparatory process for reducing the electricity storage ratio of the electricity storage device is executed. Then, when the power storage ratio of the power storage device reaches a predetermined ratio or less, a filter regeneration process is performed to regenerate the filter along with high load operation of the engine. As a result, in the filter regeneration process, it is possible to prevent the high load operation of the engine from being limited in order to suppress the overcharge of the battery. As a result, it is possible to prevent the time required for the temperature of the filter to reach the temperature suitable for regeneration from being lengthened and to suppress the time required to complete the regeneration of the filter.

  In the hybrid vehicle of the present invention as described above, the control device may control the motor so that the electric vehicle travels using only the power from the motor as the preparation process. Further, the control device may limit the allowable input power of the power storage device as the preparation process. In this way, the power storage ratio of the power storage device can be reduced.

It is a block diagram which shows the outline of a structure of the hybrid vehicle 20 as one Example of this invention. 6 is a flowchart showing an example of a control routine executed by HVECU 70.

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

  FIG. 1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 as an embodiment of the present invention. As shown, the hybrid vehicle 20 of the embodiment has an engine 22, a planetary gear 30, motors MG1 and MG2, inverters 41 and 42, a battery 50 as a power storage device, and a hybrid electronic control unit (hereinafter, referred to as " HVECU) 70).

  The engine 22 is configured as an internal combustion engine that outputs power using gasoline or light oil as fuel, and is connected to a carrier of a planetary gear 30 via a damper 28. A purification device 25 and a particulate matter removal filter (hereinafter referred to as “PM filter”) 25f are attached to the exhaust system of the engine 22. The purification device 25 has a catalyst 25a that purifies unburned fuel and nitrogen oxides in the exhaust gas of the engine 22. The PM filter 25f is formed of ceramics, stainless steel, or the like as a porous filter and traps particulate matter (PM: Particulate Matter) such as soot in the exhaust gas. The operation of the engine 22 is controlled by an engine electronic control unit (hereinafter referred to as “engine ECU”) 24.

  Although not shown, the engine ECU 24 is configured as a microprocessor centered on a CPU, and in addition to the CPU, includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port. Prepare Signals from various sensors necessary for controlling the operation of the engine 22 are input to the engine ECU 24 via input ports. The signal input to the engine ECU 24 includes, for example, a crank angle θcr from a crank position sensor 23a that detects the rotational position of the crankshaft 26 of the engine 22 and a water temperature sensor 23b that detects the temperature of the cooling water of the engine 22. The cooling water temperature Tw can be mentioned. Further, in the exhaust system of the engine 22, the air-fuel ratio AF from the air-fuel ratio sensor 25b attached upstream of the purification device 25, and in the exhaust system of the engine 22 oxygen attached downstream of the purification device 25. The oxygen signal O2 from the sensor 25c can also be mentioned. Furthermore, the differential pressure ΔP from the differential pressure sensor 25g that detects the differential pressure before and after the PM filter 25f (the differential pressure between the upstream side and the downstream side) can be mentioned. Various control signals for controlling the operation of the engine 22 are output from the engine ECU 24 through the output port. The engine ECU 24 is connected to the HVECU 70 via a communication port.

  The engine ECU 24 calculates the rotation speed Ne of the engine 22 based on the crank angle θcr from the crank position sensor 23a, and calculates the temperature (catalyst temperature) Tc of the catalyst 25a based on the cooling water temperature Tw from the water temperature sensor 23b. (Estimate) Further, the engine ECU 24 uses the intake air amount Qa from an air flow meter (not shown) and the rotation speed Ne of the engine 22 to produce volume efficiency (actual intake in one cycle with respect to the stroke volume of the engine 22 per cycle). The volume ratio of air) KL is calculated. Further, the engine ECU 24 calculates the PM deposition amount Qpm as the deposition amount of the particulate matter deposited on the PM filter 25f based on the differential pressure ΔP from the differential pressure sensor 25g, the engine speed Ne of the engine 22, and the volume efficiency. The filter temperature Tf as the temperature of the PM filter 25f is calculated based on KL.

  The planetary gear 30 is configured as a single pinion type planetary gear mechanism, and has a sun gear, a ring gear, a plurality of pinion gears meshing with the sun gear and the ring gear, respectively, and a carrier that supports the plurality of pinion gears to rotate (rotate) and revolve. Have and. The sun gear of the planetary gear 30 is connected to the rotor of the motor MG1. The ring gear of the planetary gear 30 is connected to a drive shaft 36 that is connected to the drive wheels 39a and 39b via a differential gear 38. As described above, the crankshaft 26 of the engine 22 is connected to the carrier of the planetary gear 30 via the damper 28. Therefore, it can be said that the motor MG1, the engine 22, the drive shaft 36, and the motor MG2 are connected to the sun gear, the carrier, and the ring gear as the three rotating elements of the planetary gear 30 so as to be arranged in this order in the alignment chart of the planetary gear 30.

  The motor MG1 is configured as, for example, a synchronous generator motor, and the rotor is connected to the sun gear of the planetary gear 30 as described above. The motor MG2 is configured as, for example, a synchronous generator motor, and the rotor is connected to the drive shaft 36. Inverters 41 and 42 are used to drive motors MG1 and MG2, and are connected to battery 50 via power line 54. A smoothing capacitor 57 is attached to the power line 54. The motors MG1 and MG2 are rotationally driven by switching control of a plurality of switching elements (not shown) of inverters 41 and 42 by a motor electronic control unit (hereinafter referred to as “motor ECU”) 40.

  Although not shown, the motor ECU 40 is configured as a microprocessor centered on a CPU, and in addition to the CPU, includes a ROM that stores a processing program, a RAM that temporarily stores data, an input / output port, and a communication port. Prepare The motor ECU 40 has signals from various sensors necessary for driving and controlling the motors MG1 and MG2, for example, rotational positions θm1 from rotational position detection sensors 43 and 44 that detect rotational positions of rotors of the motors MG1 and MG2. , Θm2 and phase currents Iu1, Iv1, Iu2, Iv2 from the current sensors 45u, 45v, 46u, 46v for detecting the currents flowing in the respective phases of the motors MG1, MG2, etc. are input through the input ports. From the motor ECU 40, switching control signals and the like to the plurality of switching elements of the inverters 41 and 42 are output via the output port. The motor ECU 40 is connected to the HVECU 70 via a communication port. The motor ECU 40, based on the rotational positions θm1 and θm2 of the rotors of the motors MG1 and MG2 from the rotational position detection sensors 43 and 44, the electrical angles θe1 and θe2 of the motors MG1 and MG2, the angular velocities ωm1 and ωm2, and the rotational speeds Nm1 and Nm2. Is being calculated.

  The battery 50 is configured as, for example, a lithium ion secondary battery or a nickel hydride secondary battery, and is connected to the inverters 41 and 42 via the power line 54 as described above. The battery 50 is managed by a battery electronic control unit (hereinafter, referred to as “battery ECU”) 52.

  Although not shown, the battery ECU 52 is configured as a microprocessor centered on a CPU, and in addition to the CPU, includes a ROM that stores a processing program, a RAM that temporarily stores data, an input / output port, and a communication port. Prepare Signals from various sensors necessary for managing the battery 50 are input to the battery ECU 52 via an input port. As the signal input to the battery ECU 52, for example, the voltage Vb of the battery 50 from the voltage sensor 51a attached between the terminals of the battery 50, or the voltage Vb of the battery 50 from the current sensor 51b attached to the output terminal of the battery 50, can be used. The current Ib (a positive value when discharging from the battery 50) and the temperature Tb of the battery 50 from the temperature sensor 51c attached to the battery 50 can be mentioned. The battery ECU 52 is connected to the HVECU 70 via a communication port. The battery ECU 52 calculates the storage ratio SOC based on the integrated value of the current Ib of the battery 50 from the current sensor 51b, and the battery 50 based on the calculated storage ratio SOC and the temperature Tb of the battery 50 from the temperature sensor 51c. The permissible input / output powers Win and Wout are calculated. The charge ratio SOC is a ratio of the amount of electric power that can be discharged from the battery 50 to the total capacity of the battery 50.

  Although not shown, the HVECU 70 is configured as a microprocessor centered on a CPU, and includes, in addition to the CPU, a ROM that stores a processing program, a RAM that temporarily stores data, an input / output port, and a communication port. .. Signals from various sensors are input to the HVECU 70 via input ports. Examples of the signal input to the HVECU 70 include an ignition signal from the ignition switch 80 and a shift position SP from a shift position sensor 82 that detects the operation position of the shift lever 81. Further, an accelerator opening Acc from an accelerator pedal position sensor 84 for detecting the amount of depression of the accelerator pedal 83, a brake pedal position BP from a brake pedal position sensor 86 for detecting the amount of depression of the brake pedal 85, and a vehicle speed sensor 88. The vehicle speed V can also be mentioned. The HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port as described above.

  The hybrid vehicle 20 of the embodiment thus configured is in a hybrid traveling mode (HV traveling mode) in which the vehicle travels with the rotation of the engine 22 or an electric traveling mode (EV traveling mode) in which the vehicle travels with the rotation of the engine 22 stopped. To run.

  In the HV traveling mode, the traveling torque Td * required for traveling (required by the drive shaft 36) is set based on the accelerator opening Acc and the vehicle speed V by cooperative control of the HVECU 70, the engine ECU 24, and the motor ECU 40. Then, the engine 22 and the motors MG1, MG2 are controlled so that the traveling torque Td * is output to the drive shaft 36 within the range of the allowable input / output electric power Win, Wout of the battery 50 with the rotation of the engine 22.

  In the EV traveling mode, the traveling torque Td * is set based on the accelerator opening Acc and the vehicle speed V by the coordinated control of the HVECU 70, the engine ECU 24, and the motor ECU 40, and the rotation of the engine 22 is stopped to allow the battery 50 to operate. The motor MG2 is controlled so that the traveling torque Td * is output to the drive shaft 36 within the range of the input / output powers Win and Wout.

  Next, the operation of the hybrid vehicle 20 of the embodiment thus configured, particularly the operation when the PM filter 25f needs to be regenerated, will be described. FIG. 2 is a flowchart showing an example of a control routine executed by the HVECU 70. This routine is repeatedly executed.

  When the processing routine of FIG. 2 is executed, the HVECU 70 first inputs the PM accumulation amount Qpm calculated by the engine ECU 24 through communication (step S100), and compares the input PM accumulation amount Qpm with the threshold value Qpmref ( Step S110). Here, the threshold value Qpmref is a threshold value for determining whether or not the PM filter 25f needs to be regenerated. When the PM accumulation amount Qpm is less than the threshold value Qpmref, it is determined that the PM filter 25f does not need to be regenerated, and this routine is ended.

  When the PM accumulation amount Qpm is equal to or larger than the threshold value Qpmref in step S110, it is determined that the PM filter 25f needs to be regenerated, and the preparatory process for reducing the power storage ratio SOC of the battery 50 by the cooperative control with the engine ECU 24 and the motor ECU 40. The execution is started (step S120). Here, in the preparation process, the EV running mode is selected and the allowable input power Win of the battery 50 is limited (for example, set to an approximate value 0), that is, the charging of the battery 50 is limited, so that the charge ratio SOC of the battery 50 is reduced. Was to be lowered.

  Then, the storage ratio SOC of the battery 50 calculated by the battery ECU 52 is input by communication (step S130), the storage ratio SOC of the battery 50 is compared with the threshold value Sref (step S140), and the storage ratio SOC of the battery 50 is set to the threshold value. When it is larger than Sref, the process returns to step S130.

  In this way, the processes of steps S130 and S140 are repeatedly executed while executing the preparation process, and when the storage ratio SOC of the battery 50 reaches the threshold value Sref or less, the execution of the preparation process is ended (step S150), and the filter regeneration process is executed. Then (step S160), this routine ends.

  Here, in the filter regeneration process, for example, the engine 22 is operated under a high load to raise the temperature of the PM filter 25f (filter temperature Tf) to a reproducible temperature Tfref suitable for regeneration, and then the engine is activated when the accelerator is turned off. This is performed by cutting the fuel of 22 and motoring the engine 22 by the motor MG1 to supply air (oxygen) to the PM filter 25f to burn the particulate matter deposited on the PM filter 25f. When the engine 22 is operated under a high load, surplus energy (surplus amount for the traveling power Pd * obtained by multiplying the traveling torque Td * by the rotation speed Nd of the drive shaft 36) is generated, and the battery MG is generated by the motor MG1. Be charged. In the filter regeneration process, specifically, when the storage ratio SOC of the battery 50 is high when the filter temperature Tf is raised to the regenerable temperature Tfref, the high load of the engine 22 is suppressed in order to suppress the overcharge of the battery 50. You may have to restrict driving. On the other hand, by decreasing the electricity storage ratio SOC of the battery 50 before raising the filter temperature Tf to the regenerable temperature Tfref, when the filter temperature Tf is raised to the regenerable temperature Tfref, It is possible to suppress that the high load operation of the engine 22 must be restricted in order to suppress overcharge. As a result, it is possible to prevent the time required to increase the filter temperature Tf to the reproducible temperature Tfref from being lengthened, and to suppress the time required to complete the regeneration of the PM filter 25f.

  In the hybrid vehicle 20 of the embodiment described above, when the PM accumulation amount Qpm reaches or exceeds the threshold value Qpmref, a preparatory process for reducing the storage ratio SOC of the battery 50 is executed, and the storage ratio SOC of the battery 50 falls below the threshold value Sref. When it arrives, the filter regeneration process is executed. Accordingly, when the filter temperature Tf is raised to the regenerable temperature Tfref, it is possible to prevent the high load operation of the engine 22 from being limited in order to suppress the overcharge of the battery 50. As a result, it is possible to prevent the time required to increase the filter temperature Tf to the reproducible temperature Tfref from being lengthened, and to suppress the time required to complete the regeneration of the PM filter 25f.

  In the hybrid vehicle 20 of the embodiment, the EV traveling mode is selected and the allowable input power Win of the battery 50 is limited as the preparation process, but only one of these may be performed.

  In the hybrid vehicle 20 of the embodiment, the PM deposition amount Qpm is calculated based on the differential pressure ΔP from the differential pressure sensor 25g. However, the PM deposition amount Qpm is calculated based on the engine speed Ne of the engine 22, the fuel injection amount, and the ignition timing. The quantity Qpm may be calculated. Further, of the temporary PM accumulation amount Qpm1 calculated based on the differential pressure ΔP from the differential pressure sensor 25g and the temporary PM accumulation amount Qpm2 calculated based on the rotation speed Ne of the engine 22, the fuel injection amount, and the ignition timing. The larger one may be set as the PM accumulation amount Qpm.

  In the hybrid vehicle 20 of the embodiment, the battery 50 is used as the power storage device, but a capacitor may be used instead of the battery 50.

  Although the hybrid vehicle 20 of the embodiment includes the engine ECU 24, the motor ECU 40, the battery ECU 52, and the HVECU 70, at least two of them may be configured as a single electronic control unit.

  In the embodiment, the configuration of the hybrid vehicle 20 in which the engine 22 and the motors MG1, MG2 are connected to the planetary gear 30 and the battery 50 is electrically connected to the motors MG1, MG2 has been described. However, as long as it is a hybrid vehicle including an engine, a generator capable of generating power using power from the engine, a running motor, and a power storage device that exchanges electric power with the generator and the motor, any configuration may be adopted. Good.

  Correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem will be described. In the embodiment, the engine 22 corresponds to an “engine”, the motor MG1 corresponds to a “generator”, the motor MG2 corresponds to a “motor”, the battery 50 corresponds to a “power storage device”, the HVECU 70 and the engine ECU 24. The motor ECU 40 and the motor ECU 40 correspond to a “control device”.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the section of means for solving the problem. This is an example for specifically explaining the mode for carrying out the invention, and does not limit the elements of the invention described in the column of means for solving the problem. That is, the interpretation of the invention described in the column of means for solving the problem should be made based on the description in that column, and the embodiment is the invention of the invention described in the column of means for solving the problem. This is just a specific example.

  Although the embodiments for carrying out the present invention have been described above with reference to the embodiments, the present invention is not limited to these embodiments, and various embodiments are possible within the scope not departing from the gist of the present invention. Of course, it can be implemented.

  INDUSTRIAL APPLICABILITY The present invention can be used in the hybrid vehicle manufacturing industry and the like.

  20 hybrid vehicle, 22 engine, 23a crank position sensor, 23b water temperature sensor, 24 engine electronic control unit (engine ECU), 25 purification device, 25a catalyst, 25b air-fuel ratio sensor, 25c oxygen sensor, 25f PM filter, 25g differential pressure Sensor, 26 crankshaft, 28 damper, 30 planetary gear, 36 drive shaft, 38 differential gear, 39a, 39b drive wheel, 40 motor electronic control unit (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 45u, 45v, 46u, 46v current sensor, 50 battery, 51a voltage sensor, 51b current sensor, 51c temperature sensor, 52 battery electronic control unit (battery ECU), 54 power line, 5 Condenser, 70 Hybrid electronic control unit (HVECU), 80 Ignition switch, 81 Shift lever, 82 Shift position sensor, 83 Accelerator pedal, 84 Accelerator pedal position sensor, 85 Brake pedal, 86 Brake pedal position sensor, 88 Vehicle speed sensor, MG1 , MG2 motor.

Claims (1)

An engine with a filter attached to the exhaust system to remove particulate matter,
A generator capable of generating power using power from the engine,
A motor for traveling,
A power storage device that exchanges electric power with the generator and the motor;
A control device for controlling the engine, the generator, and the motor;
A hybrid vehicle comprising:
When the amount of particulate matter deposited on the filter reaches a predetermined amount or more, the control device executes a preparatory process for reducing the power storage ratio of the power storage device, and the power storage ratio of the power storage device is equal to or lower than a predetermined ratio. When it reaches, to perform a filter regeneration process of regenerating the filter with high load operation of the engine,
Hybrid car.

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