JP4081765B2 - Control device for hybrid vehicle - Google Patents

Description

  The present invention relates to a control device for a hybrid vehicle, and in particular, operates a motor generator as a generator when the vehicle decelerates to regenerate kinetic energy of the vehicle and controls a regenerative torque when starting acceleration from a decelerated state. The present invention relates to a control device for a hybrid vehicle.

  As a vehicle, a hybrid vehicle including a motor generator (hereinafter referred to as “motor”) in addition to an engine has been proposed for the purpose of improving fuel efficiency. When the hybrid vehicle decelerates, the motor is operated as a generator, and the kinetic energy of the vehicle is regenerated and recovered as electric energy.

Conventionally, in a hybrid vehicle, when a vehicle is braked by converting a part of the kinetic energy of the vehicle into electric energy by a motor during deceleration, the amount of regenerative power generated by the motor is determined based on the engine speed, There is a configuration in which the speed decreases as the rotational speed decreases and is set to zero (0) when the rotational speed is less than the fuel cut return rotational speed. With such a configuration, when the fuel supply is resumed by the fuel supply amount control means, the engine return torque is not impaired by the regenerative braking torque, and the engine stall can be surely prevented. On the other hand, it is possible to eliminate the concern that the engine will stop and to ensure driving comfort. Further, when the engine rotation speed approaches the return rotation speed from the predetermined threshold, the fuel supply amount control means restarts the fuel supply by gradually bringing the regenerative power generation amount closer to zero (0). Therefore, by suddenly stopping the deceleration regeneration, it is possible to avoid an unexpected shock in the traveling direction acting on the occupant, thereby realizing a good running feeling.
Also, as a method of preventing a shock in the traveling direction due to an increase in engine torque due to the start of fuel supply, the hybrid vehicle performs fuel cut during deceleration and keeps the throttle opening fully open. The pumping loss is allocated to the regenerative torque of the motor / generator. At the start of acceleration, the throttle opening is returned from full open, the fuel cut is restored, and the regeneration of the motor / generator is stopped by delaying the timing by a predetermined time. As a result, excessive torque at the start of acceleration caused by a delay in reduction of the intake air amount with respect to changes in the throttle opening is absorbed by the recovered torque of the motor / generator to prevent the occurrence of a shock.
Japanese Patent No. 3350465 JP 2002-166754 A

  Conventionally, however, in the hybrid vehicle described above, Patent Document 1 has an effect of preventing a shock in the traveling direction due to a sudden decrease in the regenerative braking torque when the fuel supply is started. There is no mention of a shock in the traveling direction due to the operation, and particularly when the fuel supply is started by depressing the accelerator pedal, there is a disadvantage that a large acceleration shock may occur.

  Further, in the above-mentioned Patent Document 2, at the start of acceleration, the regeneration of the motor / generator is stopped by delaying for a predetermined time. However, the motor / generator torque setting method during this delay is stopped. Is not mentioned in particular, and since the engine torque and the degree of increase when starting acceleration depend on the vehicle state such as the throttle opening, the motor / generator torque during the delay is temporarily If the value is constant regardless of the vehicle state, there is a disadvantage that the acceleration shock is not sufficiently suppressed.

The present invention relates to a hybrid vehicle including an engine and a motor generator capable of driving and assisting the engine, and throttle opening detection means capable of detecting the throttle opening to detect the acceleration state or the deceleration state of the hybrid vehicle. And a control means for controlling the amount of regenerative power generated by the motor generator and regeneratively generated by the motor generator, and the control means detects the load state detected by the throttle opening detection means. In a hybrid vehicle control device that performs regenerative power generation control at least when a set time elapses when the vehicle changes from a deceleration state to an acceleration state, the control unit responds to a throttle opening amount detected by the throttle opening detection unit. Regenerative power generation control so that the regenerative power generation control amount increases as the throttle opening increases. It has a table for setting and when said load status detected changes in acceleration state from the deceleration state by the throttle opening detection means, while increasing the torque of the engine, regenerative power generation control is set in the table The regenerative power generation control amount is controlled to be large so that the motor torque becomes larger in the acceleration state than in the deceleration state, and the regenerative power generation control is performed so that the regenerative power generation control amount is maintained until a predetermined set time elapses. It is characterized by carrying out.

  The control device for a hybrid vehicle according to the present invention controls a regenerative power generation amount regenerated by a motor generator, and at least is set when the load state detected by the load state detection means changes from a deceleration state to an acceleration state. Since regenerative power generation control is performed until time elapses, it is possible to reduce the acceleration shock that occurs due to an increase in engine torque when shifting from deceleration to acceleration, thereby realizing smooth running Because it is possible, it can contribute to the improvement of product power.

The present invention realizes the object of reducing acceleration shock when shifting from deceleration to acceleration by controlling the regenerative torque when starting acceleration from the deceleration state.
Hereinafter, embodiments of the present invention will be described in detail and specifically based on the drawings.

  1 to 8 show an embodiment of the present invention.

  In FIG. 8, 2 is a hybrid vehicle (hereinafter referred to as “vehicle”), 4 is an engine mounted on the vehicle 2, and 6 is connected to a crankshaft (not shown) of the engine 4 to drive the engine 4. Assistable motor generator (hereinafter referred to as “motor”), 8 is an automatic transmission connected to the motor 6, 10 is a differential, 12 and 12 are axles, 14 and 14 are drive wheels, 16 is a battery, 18 is It is a control device.

  The engine 4 includes a fuel injection valve 20 and is driven by combustion of fuel injected from the fuel injection valve 20. The motor 6 is driven by electric energy, has a function capable of driving and assisting the engine 4, and has a power generation function.

  The automatic transmission 8 includes a fluid torque converter 22 and a shift control unit 24 such as a gear. Although not shown, the torque converter 22 includes a pump, a stator, and a turbine, and amplifies and transmits torque from the pump side to the turbine side. As shown in FIG. 8, the torque converter 22 is provided with a clutch-type lockup mechanism 28 having a lockup solenoid 26. Further, the shift control unit 24 is provided with a shift solenoid 30 that controls the shift.

  The motor 6 communicates with a control means (ECM) 34 via an inverter 32 communicated with the battery 16, and the operation is controlled by the control means 34.

  The control means 34 includes a fuel injection valve 20 that injects fuel into the engine 4, a lockup solenoid 26 that operates a lockup mechanism 28 of the torque converter 22, a shift solenoid 30 that performs shift control by the shift control unit 12, and intake air An ISC valve (idle speed control valve) 38 of an idle air control mechanism 36 that controls the amount of idle air in the system communicates.

  The control means 34 includes a vehicle speed sensor 40 that detects the vehicle speed, an engine rotation sensor 42 that detects the engine rotation speed, and a turbine rotation sensor 44 that detects the rotation speed of a turbine (not shown) of the torque converter 22. A throttle sensor 46 which is a throttle opening detecting means capable of detecting the throttle opening, a brake switch 48 which is turned on when a brake pedal (not shown) is depressed, and a shift position switch which detects a shift position of the automatic transmission 8. 50 is in contact.

  In this embodiment, the throttle sensor 46 functions as a load state detecting means capable of detecting the acceleration state or the deceleration state of the vehicle 2 and detects the throttle opening amount as a load amount.

  When a predetermined fuel cut condition is satisfied during deceleration of the vehicle 2, the control means 34 stops fuel injection from the fuel injection valve 20 to improve fuel efficiency and performs fuel cut control. When the fuel cut return condition is satisfied, a deceleration-time fuel cut control unit 52 is provided that performs return control from the fuel cut state to the normal control state.

  The control unit 34 includes a regenerative power generation control unit 54 that controls the amount of regenerative power generated by the motor 6 and also includes a time measuring unit 56 that measures time. The throttle sensor 46 serving as a load state detection unit When the detected load state, which is the throttle opening state, changes from the deceleration state to the acceleration state, regenerative power generation control is performed until at least the set time (indicated by T1 in FIG. 3) has elapsed.

  Further, the control means 34 adjusts the regenerative power generation control amount in accordance with the throttle opening amount which is the load amount detected by the throttle sensor 46.

  Furthermore, the control means 34 corrects the regenerative power generation amount that is performed when the acceleration state is changed in accordance with the regenerative power generation amount that is performed in the deceleration state, which is the state immediately before the transition to the acceleration state.

  The control means 34 controls the lockup mechanism 28 in the high load range and also performs the slip control in the low and middle load range. As shown in the lockup diagram of FIG. Even when the vehicle 2 is decelerating, lock-up (including slip lock-up) control is performed in order to lengthen the fuel cut time during deceleration and increase the amount of regenerative power generation. That is, in the automatic transmission 8 provided with the torque converter 22 with the lockup mechanism 28, the shock at the time of acceleration shift can be reduced if the lockup is released at the time of deceleration, but in this embodiment, the deceleration is reduced. Lock-up (including slip lock-up) control is performed even when the vehicle 2 is decelerating in order to lengthen the fuel cut time and increase the amount of regenerative power generation.

  In the lockup diagram of FIG. 6, a slip region S and a lockup region R for controlling the operation of the lockup mechanism 28 are set according to the vehicle speed and the throttle opening. That is, in FIG. 6, the throttle opening is between zero (0) and TH2 between the vehicle speed V1 and the vehicle speed V2, the throttle opening is up to TH3 until the vehicle speed V3, and the throttle opening is less than TH1 at the vehicle speed V2 or higher. A slip region S for controlling the lock-up mechanism 28 is set. On the other hand, when the vehicle speed is V2 to V4, the throttle opening gradually increases from TH2 to TH4, and the throttle opening is greater than TH1 and less than TH4. In addition, when the vehicle speed is V2 or higher, a lockup region R for lockup control of the lockup mechanism 28 is set. Here, there is a relationship of V1 <V2 <V3 <V4, and a relationship of TH1 <TH2 <TH3 <TH4.

  As shown in FIG. 7, the control means 34 determines whether or not to perform fuel cut during deceleration by contacting an engine rotation sensor 42 that detects the engine speed and a throttle sensor 46 that detects the throttle opening. A fuel cut execution determination unit 34A, a basic regenerative torque calculation unit 34B that communicates with the engine rotation sensor 42 and the throttle sensor 46 and contacts the fuel cut execution determination unit 34A to calculate a basic regenerative torque, and a fuel cut execution determination unit 34C is connected to the fuel cut return transition determination unit 34C that determines when the fuel cut return transition is made, and the fuel cut return transition determination unit 34C and the basic regenerative torque calculation unit 34B. A regenerative torque calculation unit 34D for decelerating for calculating a regenerative torque command signal for deceleration when the throttle is fully closed; Acceleration transition basic regenerative torque calculation section 34E that communicates with sensor 46 to calculate the basic regenerative torque during acceleration transition, attenuation start determination timing section 34F that communicates with throttle sensor 46, and acceleration transition basic regenerative torque calculation section 34E And an acceleration transition regenerative torque calculator 34G that calculates a regeneration torque (acceleration transition regenerative torque command value other than when the throttle is fully closed) by contacting the damping start determination timing unit 34F, and this acceleration transition regeneration. Regenerative torque during deceleration (regenerative torque command value during deceleration when the throttle is fully closed) or regenerative torque during acceleration transition (when the throttle is fully closed) selected by contacting the torque calculator 34G and the regenerative torque calculator 34D during deceleration And a torque command switch 34H that outputs a regenerative torque command value during acceleration transition to the inverter 32 as a torque command. .

  In the deceleration regeneration torque calculation unit 34D, as shown in the deceleration basic regeneration torque calculation table of FIG. 5, the regeneration torque command value is set with the engine speed as a parameter, and in the case of fuel supply (indicated by a solid line). The engine rotation speed gradually increases from NE1, and when the engine rotation speed is NE3, it becomes a constant value K. After the engine rotation speed is NE3, the engine rotation speed is maintained at this constant value K, and when the engine rotation speed is NE5, On the other hand, when the fuel is cut (indicated by a broken line), the engine speed gradually increases from NE2, and when the engine speed is NE4, the engine speed becomes a constant value K. In other words, in the basic regenerative torque calculation table at the time of deceleration shown in FIG. 5, the regenerative torque is set so that the regenerative torque is reduced as the engine rotational speed decreases and the engine rotational speed is reduced. Has changed.

  In the acceleration transition basic regenerative torque calculation unit 34E, as shown in the acceleration transition basic regenerative torque calculation table in FIG. 4, the regenerative torque command value is set with the throttle opening as a parameter, and the throttle opening increases as the throttle opening increases. In other words, the throttle opening gradually increases up to TH5, and when the throttle opening is TH5, the first value K1 is set, and when the throttle opening is from TH5 onward to TH6, the throttle opening is slightly gentler. However, when the throttle opening is TH6, the second value K2 is maintained. When the throttle opening is TH6 or higher, the second value K2 is maintained.

  That is, in the acceleration transition basic regenerative torque calculation table of FIG. 4, in order to suppress the acceleration shock, it is necessary to generate the regenerative torque so as to cancel the engine torque that changes stepwise when the fuel cut is restored. . To estimate the engine torque, there are a method of calculating from the intake air amount and a method of calculating from the throttle opening. The method of calculating the engine torque from the intake air amount can accurately estimate the torque by calculating from the throttle opening. However, in the transient state, such as during acceleration transition, the air amount measurement cycle and control means Due to the calculation period within 34, a delay occurs with respect to the actual value. On the other hand, when calculating the engine torque from the throttle opening, the accuracy of the estimated torque value is inferior, but since the air amount changes after the throttle opening changes, the delay with respect to the actual torque change is reduced. can do. Therefore, in the control of this embodiment, which is a transient control, the regenerative torque is calculated based on the throttle opening, so that the delay in generating the regenerative torque can be reduced, so that the acceleration shock can be suppressed more appropriately. It is something that can be done.

  Next, the operation of this embodiment will be described.

  First, a method for calculating the regenerative torque when the vehicle 2 is decelerated will be described based on the flowchart for calculating the regenerative torque when decelerating in FIG.

  In the calculation method of the regenerative torque at the time of deceleration, as shown in FIG. 2, when the program starts (step 202), various signals are fetched (step 204), and whether throttle opening <fuel cut determination threshold value is satisfied. Judgment is made (step 206).

  If step 206 is YES, it is determined whether or not engine speed> fuel cut determination threshold value (step 208).

  If this step 208 is YES, the fuel cut at the time of deceleration is executed (step 210), and the data at the time of fuel cut in the basic regeneration torque calculation table at the time of deceleration in FIG. The basic regenerative torque is calculated (step 212), and the regenerative torque = the basic regenerative torque at the time of fuel cut is set (step 214), and the program is returned (step 216).

  When the step 206 and the step 208 are NO, the fuel supply is executed (step 218), and the fuel supply basic data is shown from the fuel supply data (shown by the solid line) in the deceleration basic regeneration torque calculation table of FIG. A regenerative torque is calculated (step 220), and it is determined whether or not the fuel cut recovery transition is in progress (step 222).

  If this step 222 is YES, the regenerative torque is gradually increased until the regenerative torque = the basic regenerative torque at the time of fuel supply (step 224), and the program is returned (step 216).

  On the other hand, when the step 222 is NO, the regenerative torque is set to the basic regenerative torque at the time of fuel supply (step 226), and the program is returned (step 216).

  Next, a method for calculating the regenerative torque at the time of acceleration transition of the vehicle 2 will be described based on the flowchart for calculating regenerative torque at the time of acceleration transition in FIG.

  In the calculation method of the regenerative torque at the time of acceleration transition, as shown in FIG. 1, when the program starts (step 102), various signals are fetched (step 104), and it is determined whether or not the control execution flag = 1. (Step 106).

  If this step 106 is NO, it is determined whether or not the throttle opening has changed from fully closed to other than fully closed (step 108). If this step 108 is YES, the control execution flag = 1 is set (step 110).

After the processing of step 110 and when step 106 is YES, after the throttle opening changes from fully closed to other than fully closed, a set time ( X : between time t1 and time t2 in FIG. 3) It is determined whether or not the time has elapsed (step 112).

  If this step 112 is NO, the regenerative torque is calculated from the data in the acceleration regenerative basic regenerative torque table of FIG. 4 (step 114), and the program is returned (step 116).

  However, if step 112 is YES, the regenerative torque is attenuated to zero (0) (step 118), and it is determined whether regenerative torque = 0 (step 120).

  If this step 120 is YES, the control execution flag = 0 is set (step 122).

  After the process of step 122 and when the step 120 is NO, the program is returned (step 116).

  Next, the control of the vehicle 2 will be described based on the time chart of FIG.

  The time chart of FIG. 3 shows a time chart when the accelerator pedal is released (OFF) and the accelerator pedal is depressed from a state where regenerative power generation is performed during deceleration. An example is shown by a solid line, and an example when the throttle opening is small is shown by a broken line.

  That is, as shown in FIG. 3, the regeneration control during deceleration is performed until time t1, and the torque based on the deceleration regeneration torque calculation table in FIG. 5 is controlled as the regeneration torque.

  Then, the accelerator pedal is depressed at time tl, the throttle opening changes from fully closed to other than fully closed, and regenerative control at the time of acceleration transition is started.

  In this case, control is performed using the acceleration-time basic regenerative torque based on the acceleration-transition basic regenerative torque calculation table in FIG. 4 as the regenerative torque. At this time, the engine torque increases in a step-like manner by returning from the fuel cut, and then gradually increases as the intake air amount increases.

  The increase in engine torque at the time of fuel cut recovery and thereafter varies depending on the throttle opening. The larger the throttle opening, the greater the increase in engine torque.

  Then, when it is determined at time t2 that the predetermined time X has elapsed from the time t1 when the timer 56 starts the regeneration control at the time of acceleration transition, the regeneration torque starts to be attenuated. Then, when this attenuation is performed and the regenerative torque becomes zero (0) (indicated by time t3-S or time t3-B in FIG. 3), the control in this embodiment is finished, and the normal control is started. To do.

  That is, in this embodiment, in the hybrid vehicle 2 in which the engine 4 and the motor 6 are installed, when the vehicle is shifted from the deceleration state to the acceleration state, the regeneration is temporarily regenerated with the regenerative torque corresponding to the parameter related to the engine output torque. By performing the above, it is possible to apply a more appropriate regenerative torque according to the engine output torque, and more appropriately suppress a shock in the acceleration direction due to an increase in the engine torque when shifting from the deceleration state to the acceleration state. it can. Further, the parameter related to the engine output torque includes at least the throttle opening, and the control is performed so that the regenerative torque increases as the throttle opening increases, thereby detecting the change in the engine output torque with the fastest response. Thus, a shock in the acceleration direction due to an increase in engine torque can be suppressed more appropriately.

As a result, the amount of regenerative power generated by the motor 6 is controlled, and when the throttle opening state detected by the throttle sensor 46 changes from the deceleration state to the acceleration state, at least a set time (T1 in FIG. 3). When the throttle opening indicated by the broken line is small, the regeneration is performed until the time elapses from time t1 to time t3-S, and when the throttle opening indicated by the solid line is large, from time t1 to time t3-B. By implementing power generation control, it is possible to reduce the acceleration shock that occurs due to an increase in the amount of engine torque when shifting from deceleration to acceleration. It can contribute to the improvement of strength.

  Further, the control means 34 communicates with a throttle sensor 46 which is a throttle opening detecting means capable of detecting the throttle opening, and controls the regenerative power generation control amount according to the throttle opening amount detected by the throttle sensor 46. Highly accurate acceleration shock reduction control can be realized.

  Furthermore, since the load state detecting means is the throttle sensor 46 which is a throttle opening detecting means capable of detecting the throttle opening, it is not necessary to install a special dedicated detecting means, and the entire system is not complicated. .

  Furthermore, since the control means 34 corrects the regenerative power generation amount that is performed when the acceleration state is changed according to the regenerative power generation amount that is performed in the deceleration state, which is a state immediately before the transition to the acceleration state, smooth control is achieved. Allows transition from deceleration to acceleration.

  In this invention, the regenerative torque at the time of transition to acceleration is calculated based only on the throttle opening, but as shown in FIG. 5, the regenerative torque at the time of deceleration changes according to vehicle conditions such as the engine speed, It is also possible to correct the regenerative torque at the time of acceleration transition based on the immediately preceding regenerative torque so that the total torque changes smoothly. Further, since the engine torque depends not only on the throttle opening but also on the engine rotation speed, the regenerative torque at the time of acceleration transition can be calculated based on the throttle opening and the engine rotation speed.

  In the present invention, in the control of the regenerative torque at the time of acceleration transition, the motor torque is controlled so as to change in a quadratic curve after the acceleration, or fine control is performed in consideration of the weight of the vehicle and the gear position. It is also possible to suppress acceleration shock more effectively.

  Controlling the regenerative torque when starting acceleration from the deceleration state can also be applied to other controls.

It is a flowchart of regenerative torque calculation at the time of acceleration transfer. It is a flowchart of regenerative torque calculation at the time of deceleration. It is a time chart of control of a hybrid vehicle. It is a basic regenerative torque calculation table at the time of acceleration transition. It is a basic regeneration torque calculation table at the time of deceleration. It is a lockup diagram. It is a control block diagram of a control means. It is a system block diagram of the control apparatus of a hybrid vehicle.

Explanation of symbols

2 Vehicle 4 Engine 6 Motor 8 Automatic Transmission 20 Fuel Injection Valve 22 Torque Converter 26 Lockup Solenoid 28 Lockup Mechanism 30 Shift Solenoid 32 Inverter 34 Control Means 40 Vehicle Speed Sensor 42 Engine Rotation Sensor 46 Throttle Sensor 48 Brake Switch 50 Shift Position Switch

Claims (2)

A hybrid vehicle including an engine and a motor generator capable of driving and assisting the engine; throttle opening detecting means capable of detecting an acceleration state or a deceleration state of the hybrid vehicle by detecting a throttle opening; and the throttle And a control means for controlling the amount of regenerative power generated by the motor generator, and the control means accelerates the load state detected by the throttle opening degree detection means from a deceleration state. In the hybrid vehicle control device that performs regenerative power generation control at least until the set time has elapsed when the state changes , the control means controls the throttle opening amount according to the throttle opening amount detected by the throttle opening detection means. Set the regenerative power generation control amount to increase the regenerative power generation control amount as the value increases Has Buru, and when the load state detected by the throttle opening detection means is changed to the acceleration state from the decelerating state, while increasing the torque of the engine, the deceleration regenerative power generation control amount set by said table together towards the accelerating state than in the state to control increasing the regenerative power generation control amount so that the motor torque increases, performing the regenerative power generation control so as to hold up the regenerative power generation control amount is a predetermined set time elapses A hybrid vehicle control device. The control means holds the regenerative power generation control amount set in the table until the predetermined set time elapses, and the torque of the engine depends on the throttle opening amount detected by the throttle opening detection means and the The regenerative power generation control is performed so that the engine torque is gradually increased to a maximum at a predetermined set time, and the engine torque is maintained at the maximum value after the set time, while the regenerative power generation control amount is gradually decreased. The control apparatus for a hybrid vehicle according to claim 1.

Images