JP3892520B2 - Vehicle deceleration energy recovery device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle deceleration energy recovery device that recovers deceleration energy as electric energy to improve fuel efficiency.
[0002]
[Prior art]
In general, deceleration energy is converted into pumping loss due to engine braking, mechanical loss due to brake operation, and thermal energy. Therefore, in order to effectively recover this, the generator is driven during deceleration to electrically recover the deceleration energy. Various systems have been proposed.
[0003]
For example, Japanese Patent Application Laid-Open No. 61-104129 discloses a technology that can distribute a deceleration energy to an engine pumping loss and a generator loss to effectively recover wastefully consumed energy and obtain a good feeling of deceleration. Is disclosed.
[0004]
That is, a total torque for obtaining a good feeling of deceleration is set in advance, and this total torque is distributed to the torque for driving the generator for charging the battery and the torque due to the pumping loss of the engine. Driving the generator increases the charging rate of the battery, and at the same time reduces the uncomfortable feeling during deceleration by setting the throttle opening corresponding to the pumping loss.
[0005]
[Problems to be solved by the invention]
The above prior art relates to a technique for recovering part of the pumping loss of the engine as electric energy, but at the time of deceleration, in addition to the deceleration traveling using only the engine brake, the frequency of deceleration traveling by mechanical braking is relatively high, The kinetic energy generated at the time of deceleration traveling by this mechanical braking cannot be effectively recovered as electric power, and there is a limit to improving the fuel consumption.
[0006]
Moreover, in the said prior art, since the lead storage battery unsuitable for quick charge is charged, deceleration energy cannot be regenerated effectively. In this regard, for example, as disclosed in Japanese Patent Laid-Open No. Hei 6-276616, it is possible to effectively regenerate deceleration energy by using a large-capacity capacitor such as an electric double layer capacitor. When the generator is driven at the maximum load voltage for regeneration, the braking force becomes higher than the normal engine brake, the deceleration shock becomes large, and the normal feeling of deceleration is not expected, and the driver feels uncomfortable. .
[0007]
In view of the above circumstances, the first object of the present invention is to efficiently recover deceleration energy as electric energy without deteriorating the normal deceleration feeling even in deceleration traveling by forced braking in addition to deceleration traveling by engine braking. The object is to provide a vehicle deceleration energy recovery device.
[0008]
The second purpose is to improve fuel efficiency by effectively recovering deceleration energy without applying braking force more than engine braking by rapid charging during deceleration even when a large capacity capacitor is used as a storage battery. An object of the present invention is to provide a vehicle deceleration energy recovery device that can perform the above operation.
[0010]
[Means for Solving the Problems]
  In order to achieve the above object, a first according to the present invention.The decelerating energy recovery device includes an engine, a generator driven by the decelerating energy, a storage battery for charging the power generated by the generator, a brake detecting means for detecting a brake pedal depression state, and a power generator for controlling the regenerative braking torque of the generator. In a vehicle comprising a machine control unit, a means for setting a torque equivalent to an engine brake on the generator control control unit based on a vehicle speed during deceleration and a transmission gear ratio, and a torque equivalent to the engine brake A means for setting the regenerative braking torque of the generator; and when the brake detection means detects that the brake pedal has not been depressed at the time of deceleration, a regenerative braking signal corresponding to the regenerative braking torque is output to the generator, and the brake Detects pedal depression and the amount of brake pedal depression is the set play amount When it is lower, a regenerative braking signal corresponding to the regenerative braking torque corresponding to the depression amount is output to the generator, while the depression of the brake pedal is detected, and the depression amount of the brake pedal exceeds the set play amount. In some cases, a means for outputting a regenerative braking signal corresponding to the maximum braking torque to the generator and a clutch disengagement signal to a power transmission clutch interposed in the power transmission system in synchronism with the output of the regenerative braking signal or the engine And a means for outputting a full-open signal to an intake control valve interposed in the intake system.
[0011]
  First2This deceleration energy recovery device controls the engine, a generator driven by the deceleration energy, a large-capacity capacitor that charges the power generated by the generator, a brake detection means that detects the depression of the brake pedal, and the regenerative braking torque of the generator In a vehicle comprising a generator control control unit, a play amount adjusting device for adjusting the play amount of the brake pedal is connected to the brake pedal, and the generator control control unit is provided with a vehicle speed and a gearbox during deceleration. A charging rate is calculated from a means for setting a torque equivalent to the engine brake based on the gear ratio, a means for setting a regenerative braking torque of the generator based on the torque equivalent to the engine brake, and a terminal voltage of the large capacity capacitor. Means for setting the maximum load torque of the generator based on the vehicle speed; and Means for setting the maximum rechargeable braking torque of the generator based on the electric power and the maximum load torque, and regenerative braking corresponding to the regenerative braking torque when the brake detection means is not depressed by the brake detecting means during deceleration. A signal is output to the generator, and when the brake pedal depression is detected and the brake pedal depression amount is less than a set play amount, the rechargeable braking torque is compared with the rechargeable braking torque and the regenerative braking torque is compared. When the torque is less than or equal to the maximum rechargeable braking torque, a regenerative braking signal corresponding to the regenerative braking torque corresponding to the depression amount is output to the generator, while the regenerative braking torque exceeds the maximum rechargeable braking torque. When this occurs, a regenerative braking signal corresponding to the maximum chargeable braking torque is output to the generator and a brake operation signal is sent to the play amount adjusting device. Means for outputting a regenerative braking signal corresponding to a maximum braking torque when the brake pedal depression is detected and the amount of depression of the brake pedal exceeds a set play amount, and the regenerative braking And means for outputting a clutch open signal to a power transmission clutch interposed in the power transmission system in synchronization with the output of the signal or outputting a fully open signal to an intake control valve interposed in the intake system of the engine. To do.
[0012]
  First3The deceleration energy recovery device of the firstOr 2In this deceleration energy recovery apparatus, the power transmission clutch is a forward clutch provided in an automatic transmission.
[0013]
  The fourth deceleration energy recovery device is the first or second deceleration energy recovery device, wherein the intake control valve is a throttle valve, and the power generationMachineThe control control unit includes means for outputting a throttle full open signal to the throttle control control unit for controlling the opening of the throttle valve in synchronization with the output of the regenerative braking signal.
[0014]
  First5The deceleration energy recovery device of the first4In this deceleration energy recovery apparatus, the generator control control unit is provided with means for outputting a fuel cut signal to the engine control control unit in synchronization with the output of the regenerative braking signal.
[0015]
  First6The deceleration energy recovery device of the first4Or5In the described deceleration energy recovery device, the generator control control unit includes an engine brake torque when the throttle valve is fully closed and an engine brake torque when the throttle valve is fully open, which is set based on the vehicle speed during deceleration and the transmission gear ratio. A means for setting the difference as a torque corresponding to the engine brake is provided.
[0017]
  First1In this deceleration energy recovery device, a generator control control unit that controls the regenerative braking torque of the generator driven by the deceleration energy sets the torque equivalent to the engine brake based on the vehicle speed during deceleration and the transmission gear ratio. Then, the regenerative braking torque of the generator is set based on the torque corresponding to the engine brake. During deceleration, if the brake detection means detects that the brake pedal has not been depressed, a regenerative braking signal corresponding to the regenerative braking torque is output to the generator, the depression of the brake pedal is detected, and the brake pedal When the depression amount is less than the set play amount, a regenerative braking signal corresponding to the regenerative braking torque corresponding to the depression amount is output to the generator, while the brake pedal depression is detected, and the depression amount of the brake pedal is set as described above. When the play amount is exceeded, a regenerative braking signal corresponding to the maximum braking torque is output to the generator. The engine brake is reduced by fully opening the intake control valve or opening the power transmission clutch interposed in the power transmission system.
[0018]
  First2This deceleration energy recovery device is a generator control control unit that controls the regenerative braking torque of the generator driven by the deceleration energy, and sets the torque equivalent to the engine brake based on the vehicle speed during deceleration and the transmission gear ratio. The regenerative braking torque of the generator is set based on the torque equivalent to the engine brake, the charging rate is calculated from the terminal voltage of the large-capacity capacitor, and the maximum load torque of the generator is set based on the vehicle speed. Based on the charging rate and the maximum load torque, the maximum chargeable braking torque of the generator is set. During deceleration, when the brake detection means detects that the brake pedal is not depressed, it outputs a regenerative braking signal corresponding to the regenerative braking torque to the generator, detects the depression of the brake pedal, and depresses the brake pedal. When the amount is less than the set play amount, the rechargeable maximum braking torque is compared with the regenerative braking torque, and when the regenerative braking torque is less than the maximum rechargeable braking torque, the regenerative braking torque corresponding to the depression amount is met. Means for outputting a regenerative braking signal to the generator, and when the regenerative braking torque exceeds the maximum chargeable braking torque, a regenerative braking signal corresponding to the maximum rechargeable braking torque is output to the generator. And outputs a brake operation signal to the play amount adjusting device, detects the depression of the brake pedal, and sets the depression amount of the brake pedal. The regenerative braking signal corresponding to the maximum braking torque when exceeds the amount of play and outputs to the generator. The engine brake is reduced by fully opening the intake control valve or opening the power transmission clutch interposed in the power transmission system.
[0019]
  First3In the deceleration energy recovery apparatus of the first,Or 2In this deceleration energy recovery apparatus, the transmission of the engine brake is cut off by using the power transmission clutch as a forward clutch provided in the automatic transmission.
[0020]
  First4In the deceleration energy recovery apparatus, the firstOr 2In this deceleration energy recovery apparatus, the intake control valve is a throttle valve, and the throttle valve is fully opened during regenerative braking by a generator.
[0021]
  First5In the deceleration energy recovery device,4In this decelerating energy recovery device, the fuel consumption can be improved by cutting the fuel during regenerative braking by the generator.
[0022]
  First6The deceleration energy recovery device of the first4 or 5The difference between the engine brake torque when the throttle valve is fully closed and the engine brake torque when the throttle valve is fully opened is set based on the vehicle speed during deceleration and the transmission gear ratio. Set based on.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 to 10 show a first embodiment of the present invention. FIG. 8 shows a vehicle 1 equipped with a deceleration energy recovery device according to the present invention. This vehicle 1 is a four-wheel drive vehicle, and an output shaft of an automatic transmission 3 connected to an engine 2 is connected to a front wheel drive shaft 5 and a propeller shaft 7 connected to a rear wheel drive shaft 6 via a center differential device 4. The output from the automatic transmission 3 is distributed to the front and rear wheels.
[0024]
The power transmission path of the automatic transmission 3 is provided with a torque converter, a forward clutch, a transmission mechanism, and the like. For example, when the select lever is set to the neutral (N) range, the forward clutch is opened, and the front wheel drive shaft Transmission of power to 5 and the rear wheel drive shaft 6 is cut off.
[0025]
In addition, a generator 9 is connected to the propeller shaft 7 through a speed reduction mechanism unit 8 at the center. The deceleration mechanism 8 is provided with a clutch that can be selectively connected / disconnected according to the traveling state of the vehicle or manually by the driver.
[0026]
Two modules of an electric double layer capacitor 11 which is an example of a large-capacity capacitor are connected in parallel to the generator 9 via a charge / discharge circuit 10 including an inverter circuit or the like. The charge / discharge circuit 10 selectively switches the operation of the generator 9 between regenerative braking and power running in response to a regenerative braking command signal or a power running command signal output from a generator control control unit 19 which will be described later. The electric double layer capacitor 11 is charged with the electric power generated by the regenerative braking, and the electric power necessary for causing the generator 9 to power is supplied from the electric double layer capacitor 11.
[0027]
Reference numeral 12 denotes an accelerator sensor including an idle switch that is turned ON when the accelerator pedal is not depressed, and an accelerator opening sensor that detects an accelerator depression amount, and 13 is a brake sensor that detects an operation state of the brake pedal 14. As shown in FIG. 9, the brake sensor 13 is turned OFF when the brake pedal 14 is released and turned ON when the brake pedal 14 is depressed, and a brake stroke sensor 13b that detects a stroke when the brake pedal 14 is depressed. It has.
[0028]
Reference numeral 15 is an engine control control unit that detects the operating state of the engine 2 and the traveling state of the vehicle 1 and calculates the fuel injection amount, the ignition timing, and the like. A crank angle sensor 16 for detecting the engine speed is connected to the engine control control unit 15.
[0029]
Reference numeral 17 denotes an electronic throttle control (ETC) unit, which is connected to a throttle actuator 18 connected to an electric throttle valve (not shown), and controls intake system parameters such as intake air amount and accelerator pedal depression amount. Accordingly, the throttle valve opening is set, and the throttle valve opening signal is output to the throttle actuator 18 to control the throttle valve opening.
[0030]
Reference numeral 19 denotes a generator control unit. The engine speed signal calculated based on the output signal of the crank angle sensor 16 in the engine control unit 15 and a shift positive sensor for detecting the position of a shift lever (not shown). Each signal for detecting a vehicle running state such as an output shift position signal, an idle switch signal, a brake switch signal, a brake pedal stroke signal, a terminal voltage of the electric double layer capacitor 11 and a vehicle speed signal output from the vehicle speed sensor 23 Entered.
[0031]
Further, the charge / discharge circuit 10 and the brake pedal play amount adjusting valve 20 are connected to the output side of the generator control control unit 19.
[0032]
The brake pedal play amount adjusting valve 20 is disposed in the brake pedal play amount adjusting device 22. As shown in FIG. 9, the brake pedal play amount adjusting device 22 is interposed between the brake pedal 14 and a master cylinder 21 that supplies hydraulic pressure corresponding to the depression stroke of the brake pedal 14 to each brake unit. ing.
[0033]
The front end surface of the fluid cylinder 22 a provided in the brake pedal play amount adjusting device 22 is in contact with the piston rod 21 a of the master cylinder 21.
[0034]
A cylinder piston 22b interposed in the fluid cylinder 22a is connected to the brake pedal 14 via a piston rod 22c. The retainer formed in the middle of the piston rod 22c and the fluid cylinder 22a A compression spring for interposing the tip end surface of the fluid cylinder 22a to the piston rod 21a of the master cylinder 21 at all times is interposed.
[0035]
The fluid cylinder 22a is divided into a front chamber 22d and a rear chamber 22e by the cylinder piston 22b, and both the chambers 22d and 22e communicate with each other via a bypass passage 22f. A regulating valve 20 is interposed.
[0036]
The brake pedal play amount adjusting valve 20 is opened and closed based on a control signal from the generator control unit 19, and is normally open, and when the brake pedal 14 is released, Due to the biasing force of the compression spring, the fluid cylinder 22a and the cylinder piston 22b are relatively positioned at a position having the initial play amount X0. When the brake pedal 14 is depressed from this state, during the stroke corresponding to the play amount XO, the fluid in the front chamber 22d passes through the bypass passage 22f and moves to the rear chamber 22e, and the piston rod 21a of the master cylinder 21 is not moved. When the play amount X0 or more is stepped on, the cylinder piston 22b comes into contact with the front end of the cylinder 22a to operate integrally, and the piston rod 21a of the master cylinder 21 is moved. When the brake pedal play amount adjusting valve 20 is closed, the fluid is prevented from moving, and the fluid cylinder 22a operates integrally with the piston rod 22c without play amount.
[0037]
In the generator control control unit 19, the regenerative braking torque of the generator 9 and the opening / closing control of the brake pedal play amount adjusting valve 20 at the time of deceleration set based on the input parameters are executed according to the flowcharts of FIGS. 2 to 4. .
[0038]
2 and 3 show the regenerative braking torque setting routine during deceleration. In this routine, first, in step S101, it is determined whether the accelerator pedal is not depressed based on the output signal of the idle switch. If the accelerator switch is not depressed, the process proceeds to step S102, and the accelerator pedal is turned off. When in the depressed state, the process branches to step S114.
[0039]
Then, when proceeding to step S102, the current vehicle speed V is compared with a predetermined vehicle speed Vo for determining whether or not the vehicle is decelerating that requires engine braking, and when decelerating when V ≧ Vo, the process proceeds to step S103. When the vehicle runs at a low speed or stops just before the stop of V <Vo, the process branches to step S114.
[0040]
Thereafter, when the process proceeds to step S103, it is determined whether or not the brake pedal is not depressed based on the output signal of the brake switch. When the brake pedal is depressed, that is, in the braking state, the process branches to step S109.
[0041]
If it is determined in steps S101 to S103 that the idle switch is ON, the vehicle is decelerating, and the brake switch is OFF, the process proceeds to step S104. Set the torque.
[0042]
First, in step S104, the map shown in FIG. 5 in which the engine brake torque during deceleration traveling determined by the current speed ratio ε and the vehicle speed V is stored as the required engine brake torque T1 is referenced with interpolation calculation, or Set by calculation.
[0043]
Next, in step S105, the regenerative braking torque of the generator 9 corresponding to the required engine brake equivalent torque T1 is set according to the regenerative braking torque setting subroutine shown in FIG.
[0044]
In this subroutine, first, in step S201, the required engine brake equivalent torque T1 is read, and in step S202, the maximum load torque Tmax of the generator 9 is calculated based on the vehicle speed V (the generator speed), or as shown in FIG. It sets by interpolation calculation from the table of generator characteristics shown, and reads the terminal voltage E1 of the electric double layer capacitor 11 in step S203.
[0045]
Thereafter, in step S204, the insufficient torque Tm that cannot be taken out even if the maximum condition is given to the generator 9 based on the terminal voltage E1 of the electric double layer capacitor 11 is determined based on the charging characteristics of the electric double layer capacitor 11 shown in FIG. It is obtained from an experiment or the like, and a table storing the values is referred to with interpolation calculation or set by calculation.
[0046]
In step S205, the required engine brake equivalent torque T1 is compared with a value obtained by subtracting the insufficient torque Tm from the maximum load torque Tmax (chargeable maximum braking torque). When T1 <Tmax-Tm, the generator 9 Since the required engine brake equivalent torque T1 can be provided by the regenerative operation, the process proceeds to step S206, where the required engine brake equivalent torque T1 is set as the regenerative braking torque T2 by the generator 9 (T2 ← T1). Exit. Further, when T1 ≧ Tmax−Tm, the required engine brake equivalent torque T1 cannot be achieved only by regenerating the generator 9, and the process proceeds to step S207, where the regenerative braking torque T2 is set to the rechargeable maximum braking torque (Tmax−Tm). Set (T2 ← Tmax-Tm) and exit the routine. In this case, the brake feeling due to the regenerative braking torque T2 can be considered to be smaller than the driver's feeling, but the braking feeling beyond that is left to the driver's brake operation.
[0047]
After completion of the setting of the regenerative braking torque in step S105 as described above, in step S106 shown in FIG. 2, the forward clutch provided in the automatic transmission 3 is opened to shut off the power transmission path of the drive system, and in step S107. A generator operation flag F (set during regeneration, clear during power running) is set, and in step S108, a field current as a regenerative braking signal corresponding to the regenerative braking torque T2 set in step S105 is obtained from the charge / discharge circuit 10. Output to the generator 9 and exit the routine.
[0048]
Then, regenerative braking with a predetermined torque acts on the front wheel drive shaft 5 and the rear wheel drive shaft 6 via the propeller shaft 7 by the generator 9, and the electric power generated by the regenerative braking is supplied to the electric 2 via the charge / discharge circuit 10. The multilayer capacitor 11 is charged.
[0049]
If it is determined in step S103 that the brake switch is ON, the process proceeds to step S109. In step S109 and subsequent steps, a regenerative braking torque for regenerative braking corresponding to the driver's brake operation is set.
[0050]
First, in step S109, the brake pedal stroke X calculated based on the output signal of the brake stroke sensor 13b is compared with the initial play amount XO of the brake pedal 14, and the stroke X of the brake pedal 14 with X <XO is determined as the play amount XO. When the operation is within the range, the process proceeds to step S110, and when the stroke X where X ≧ X0 exceeds the play amount X0, the process proceeds to step S113.
[0051]
In step S110, the table is referred to with interpolation calculation based on the brake pedal stroke X, or the regenerative braking torque T2 is set by calculation. In step S111, the aforementioned maximum rechargeable braking torque (Tmax-Tm) is set. Is compared with the regenerative braking torque T2, and when T2 <Tmax-Tm, the regenerative braking torque T2 by the generator 9 has a margin, so the process returns to step S108, and a regenerative braking signal corresponding to the regenerative braking torque T2 is obtained. Is output from the charge / discharge circuit 10 to the generator 9 and the routine is exited. As a result, the regenerative energy during deceleration can be effectively recovered even within the range of the play amount XO of the brake operation.
[0052]
When T2 ≧ Tmax−Tm, the regenerative operation by the generator 9 cannot achieve the brake feeling required by the driver's brake operation, so the routine proceeds to step S112 and the brake pedal play provided in the brake pedal play amount adjusting device 22 is reached. A valve closing signal is output to the amount adjusting valve 20, and the process proceeds to step S113. When a valve closing signal is output to the brake pedal play amount adjusting valve 20, the brake pedal play amount adjusting valve 20 is closed to flow the fluid flowing into the front chamber and the rear chamber of the fluid cylinder 22a. Shut off. Then, the cylinder piston 22b connected to the brake pedal 14 and the fluid cylinder 22a move together to press the piston rod 21a of the master cylinder 21, and the mechanical brake is operated even within the range of the initial play amount X0. The
[0053]
As a result, as shown in FIG. 10, when the charging rate α of the electric double layer capacitor 11 is higher than the normal brake hydraulic braking force indicated by a solid line, and regenerative braking by the generator 9 is not sufficiently obtained. As described with the wavy line, the play amount is shortened and the brake hydraulic braking force is increased early, so that the decelerating traveling without any sense of incongruity is possible without affecting the charging state of the electric double layer capacitor 11.
[0054]
Then, when the process proceeds from step S109 or step S112 to step S113, the regenerative braking torque T2 is set with the maximum chargeable braking torque (Tmax-Tm), and the process returns to step S108, and the regenerative braking torque T2 corresponding to the regenerative braking torque T2 is set. The field current as a braking signal is output from the charging / discharging circuit 10 to the generator 9 and the routine is exited.
[0055]
On the other hand, when accelerating after deceleration (idle switch OFF), or when decelerating or stopping immediately before stopping (V ≧ Vo), the process branches from step S101 or step S102 to step S114.
[0056]
Then, in step S114, the value of the generator operation flag F is referred to. When the generator 9 with F = 0 indicates the power running state, the routine exits as it is, and when the regeneration state with F = 1 is indicated. Advances to step S115, clears the generator operation flag F, engages the forward clutch provided in the automatic transmission 3 in step S116, and prepares for the subsequent start, then in step S117, the regenerative braking by the generator 9 Is released, a valve opening signal is output to the brake pedal play amount adjusting valve 20 provided in the brake pedal play amount adjusting device 22 in step S118, and the brake pedal play amount adjusting valve 20 is opened. Exit.
[0057]
As a result, the play amount of the brake pedal play amount adjusting device 22 is returned to the initial play amount Xo, and the traveling mode is returned to the normal mode.
[0058]
The electric double layer capacitor 11 is used as an auxiliary power source for assisting acceleration running by operating the generator 9 as an electric motor during acceleration operation, or supplementing a shortage of batteries.
[0059]
Thus, according to the present embodiment, energy can be effectively used by recovering deceleration energy as electric energy, and fuel efficiency can be improved. Furthermore, since deceleration characteristics equivalent to engine braking can be obtained, deceleration traveling can be performed without a sense of incongruity. Furthermore, when the charge rate α of the electric double layer capacitor 11 is high and the regenerative braking torque as expected cannot be obtained even if the generator 9 is operated in the initial stage of the deceleration traveling by forced braking using the brake. Since the brake is immediately operated even within the range of the play amount of the brake pedal, a braking operation without a sense of incongruity can be obtained even when the regenerative braking torque by the generator 9 is insufficient, Even during forced braking by the brake, deceleration energy can be recovered efficiently, and fuel consumption can be further improved.
[0060]
The present embodiment can also be applied to an electronically controlled continuously variable transmission including an electromagnetic clutch and a continuously variable transmission as an automatic transmission. In this case, the forward clutch of the present embodiment is released or coupled. Instead of the operation, the electromagnetic clutch is released or coupled, and the gear ratio ε reads the gear ratio between the primary pulley and the secondary pulley.
[0061]
FIGS. 11 to 13 show a second embodiment of the present invention. In the first embodiment described above, the power transmission system is shut off at the time of fuel cut at the time of deceleration, and the engine brake corresponding to when the throttle valve is fully closed is generated by regenerative braking by the generator 9. In the embodiment, at the time of fuel cut at the time of deceleration, the power transmission system is not cut off. Instead, the throttle valve is fully opened to reduce the engine braking force, and the regenerative braking torque corresponding to the engine brake is generated by the generator 9. It is made to generate.
[0062]
As shown in FIG. 11, a throttle control control unit (TCU) 17 opens a throttle valve (not shown) based on a vehicle speed signal, an intake system parameter such as an intake air amount, an idle switch signal, and an accelerator opening signal. The degree of air is set, and an air amount corresponding to the amount of fuel injected from the injector is supplied into the cylinder. When the throttle control valve 19 is output from the generator control unit 19, the throttle valve is fully opened.
[0063]
Hereinafter, a deceleration regenerative braking torque setting routine executed by the generator control control unit 19 in the present embodiment will be described with reference to the flowchart shown in FIG.
[0064]
First, in steps S101 to S103, when it is determined that the idle switch is turned on at a reduced speed and the current vehicle speed V is equal to or higher than the set vehicle speed Vo and the brake switch is OFF, the process proceeds to step S301. In step S302, a fuel cut signal is output to cut the fuel, and in step S302, a throttle fully open signal is output to the TCU 17, and the throttle valve is fully opened via the TCU 17 to reduce the actually applied engine brake torque.
[0065]
Thereafter, the process proceeds to step S303, and a regenerative braking torque T2 corresponding to the throttle valve fully closed is calculated. That is, based on the current speed ratio ε detected based on the vehicle speed V and the output signal from the shift position sensor based on the characteristic diagram shown in FIG. 3, the engine brake torque when the throttle valve is fully closed and the engine brake torque when the throttle is fully open And a regenerative braking torque T2 corresponding to the difference ΔT1 is set by calculation or by referring to a table.
[0066]
Thereafter, in step S107, the generator operation flag F (set during regeneration, cleared during power running) is set, and the process proceeds to step S304, where the field current as a regenerative braking signal corresponding to the regenerative braking torque T2 is converted into the charge / discharge circuit 10 described above. After that, the data is output to the generator 9 and the routine is exited.
[0067]
On the other hand, if it is determined in step S103 that the brake switch is ON, the process proceeds to step S109 shown in FIG. 3 of the first embodiment described above, and the regenerative braking torque T2 is set to a predetermined value in the routine after step S109. Then, the process returns to step S304.
[0068]
Further, at the time of acceleration traveling after deceleration traveling (idle switch OFF), or at the time of deceleration traveling immediately before stopping or at the time of stopping (V <Vo), the process branches from step S101 or step S102 to step S114, and the first embodiment described above. As in the above embodiment, the value of the generator operation flag F is referred to, and when the generator 9 with F = 0 indicates the power running state, the routine is directly exited. If F = 1 indicates a regenerative state, the process proceeds to step S115, the generator operation flag F is cleared, and in step S305, the throttle valve full open release signal is output to the TCU 17 to operate the TCU 17 normally. In step S306, a fuel return signal is output to the engine control control unit 15. In step S307, the regenerative braking by the generator 9 is released. In step S308, the brake pedal play amount adjusting device 22 is provided. After the valve closing signal is output to the brake pedal play amount adjusting valve 20 and the brake pedal play amount adjusting valve 20 is opened, the routine is exited.
[0069]
As described above, in this embodiment, when the regenerative braking is performed by the generator 9, the throttle valve is fully opened to reduce the pumping loss during deceleration, and accordingly, the recovery rate of the kinetic energy by the generator 9 is increased. Can be improved. In addition, since it is not necessary to forcibly shut off the power transmission system, an engine equipped with a TCU 17 can be easily employed in a vehicle equipped with a manual transmission in addition to a vehicle equipped with an automatic transmission. .
[0070]
【The invention's effect】
  According to the first aspect of the present invention, the regenerative braking torque is set to the torque equivalent to the engine brake by the generator, and the intake control valve is fully opened or the power transmission clutch is opened. The pumping loss can be reduced, and the deceleration energy can be effectively recovered as electric energy.
  Furthermore, not only deceleration traveling by engine braking but also deceleration traveling by mechanical braking can effectively recover deceleration energy as electric energy without impairing the feeling of deceleration, thereby improving fuel efficiency. it can.
[0072]
  Claim2According to the described invention, rapid charging is possible by adopting a large-capacity capacitor as a storage battery, and generated power corresponding to torque equivalent to engine braking during deceleration can be charged without difficulty.
[0073]
  Claim3According to the described invention, claim 1Or 2In the described invention, at the time of deceleration, the forward clutch provided in the automatic transmission is released, whereby transmission of the engine brake can be easily cut off, and deceleration energy can be recovered more effectively.
[0074]
  Claim4According to the described invention, claim 1Or 2In the described invention, by fully opening the throttle valve during deceleration, the pumping loss of the engine can be reduced and deceleration energy can be effectively recovered.
[0075]
  Claim5According to the described invention, the claims4In the described invention, fuel consumption can be improved by performing fuel cut during regenerative braking by a generator.
[0076]
  Claim6According to the described invention, the claims4 or 5In the described invention, the engine brake equivalent torque obtained when setting the regenerative braking torque of the generator is calculated from the difference between the brake torque when the throttle is fully closed and the engine brake torque when the throttle is fully open. Even when the regenerative braking torque is generated by the generator, the braking force almost equal to that of a normal engine brake is applied, so that the vehicle can be decelerated without feeling uncomfortable.
[Brief description of the drawings]
FIG. 1 is a functional block diagram of a deceleration energy recovery device according to a first embodiment.
FIG. 2 is a flowchart showing a deceleration regenerative braking torque setting routine;
FIG. 3 is a flowchart showing a deceleration regenerative braking torque setting routine (continued).
FIG. 4 is a flowchart showing a regenerative braking torque setting subroutine;
FIG. 5 is a characteristic diagram showing the relationship between the vehicle speed, the gear ratio, and the engine brake torque when the throttle valve is fully closed.
FIG. 6 is a characteristic diagram showing the relationship between the vehicle speed and the load torque of the generator.
FIG. 7 is a characteristic diagram showing the relationship between the charging rate and voltage of the electric double layer capacitor.
FIG. 8 is a plan view of the drive system of the vehicle
FIG. 9 is a side view of the brake pedal play amount adjusting device.
FIG. 10 is a characteristic diagram showing the relationship between brake pedal stroke and hydraulic braking force.
FIG. 11 is a functional block diagram of a deceleration energy recovery device according to a second embodiment.
FIG. 12 is a flowchart showing a deceleration regenerative braking torque setting routine;
FIG. 13 is a characteristic diagram showing the relationship among vehicle speed, gear ratio, and engine brake torque when the throttle valve is fully closed and fully open;
[Explanation of symbols]
1 ... Vehicle
9 ... Generator
11 ... Electric double layer capacitor
14 ... Brake pedal
15 ... Control unit for engine control
17 ... Control unit for throttle control
19 ... Control unit for generator control
T1 ... Required engine brake torque
T2: Regenerative braking torque
Tmax: Maximum load torque
(Tmax-Tm) ... Maximum braking torque
ΔT1 ... engine brake difference
V ... Vehicle speed
X ... Depression amount
Xo: Set play amount
α ... Charging rate
ε ... speed ratio

Claims (6)

An engine, a generator driven by deceleration energy, a storage battery for charging power generated by the generator, brake detection means for detecting a brake pedal depression state, and a generator control unit for controlling regenerative braking torque of the generator In the vehicle,
In the generator control control unit,
Means for setting a torque equivalent to an engine brake based on a vehicle speed during deceleration and a transmission gear ratio;
Means for setting the regenerative braking torque of the generator based on the torque equivalent to the engine brake;
During deceleration, when the brake detection means detects that the brake pedal has not been depressed, a regenerative braking signal corresponding to the regenerative braking torque is output to the generator, the brake pedal depression is detected, and the amount of depression of the brake pedal is When the play amount is less than the set play amount, a regenerative braking signal corresponding to the regenerative braking torque corresponding to the stepping amount is output to the generator, while the brake pedal stepping is detected, and the stepping amount of the brake pedal satisfies the set play amount. Means for outputting a regenerative braking signal corresponding to the maximum braking torque to the generator when exceeding,
Means for outputting a clutch release signal to a power transmission clutch interposed in the power transmission system in synchronization with the output of the regenerative braking signal or outputting a full-open signal to an intake control valve interposed in the intake system of the engine. A vehicle deceleration energy recovery device. An engine, a generator driven by deceleration energy, a large-capacitance capacitor for charging power generated by the generator, a brake detection means for detecting a brake pedal depression state, and a generator control unit for controlling the regenerative braking torque of the generator In a vehicle comprising:
A play amount adjusting device for adjusting the play amount of the brake pedal is connected to the brake pedal,
In addition, the control unit for controlling the generator
Means for setting a torque equivalent to an engine brake based on a vehicle speed during deceleration and a transmission gear ratio;
Means for setting the regenerative braking torque of the generator based on the torque equivalent to the engine brake;
Means for calculating the charging rate from the terminal voltage of the large-capacitance capacitor; means for setting the maximum load torque of the generator based on the vehicle speed;
Means for setting a maximum chargeable braking torque of the generator based on the charging rate and the maximum load torque;
During deceleration, when the brake detection means detects that the brake pedal has not been depressed, a regenerative braking signal corresponding to the regenerative braking torque is output to the generator, the brake pedal depression is detected, and the amount of depression of the brake pedal is When the play amount is less than the set play amount, the rechargeable maximum braking torque is compared with the regenerative braking torque. When the regenerative braking torque is less than the maximum chargeable braking torque, the regenerative braking torque corresponding to the stepping amount is regenerated. When a braking signal is output to the generator and the regenerative braking torque exceeds the rechargeable maximum braking torque, a regenerative braking signal corresponding to the maximum rechargeable braking torque is output to the generator and the idle The brake operation signal is output to the amount adjusting device, and the brake pedal depression is detected, and the depression amount of the brake pedal indicates the set play amount. Means for outputting a regenerative braking signal corresponding to the maximum braking torque in the generator when being e,
Means for outputting a clutch release signal to a power transmission clutch interposed in the power transmission system in synchronization with the output of the regenerative braking signal or outputting a full-open signal to an intake control valve interposed in the intake system of the engine. A vehicle deceleration energy recovery device. The vehicle deceleration energy recovery device according to claim 1 or 2 , wherein the power transmission clutch is a forward clutch provided in an automatic transmission. The intake control valve is a throttle valve;
Wherein the generator control for a control unit, wherein, characterized in that it comprises means for outputting a full throttle signal to the throttle control for the control unit for controlling the opening of the throttle valve in synchronization with the output of the regenerative braking signal Item 3. The vehicle deceleration energy recovery device according to Item 1 or 2. In the generator control control unit,
The regenerative braking signal in synchronization with the deceleration energy recovery system for a vehicle according to claim 4, characterized in that it comprises means for outputting a fuel cut signal to the engine control for the control unit to the output. In the generator control control unit,
And means for setting a difference between the engine brake torque when the throttle valve is fully closed and the engine brake torque when the throttle valve is fully opened, which is set based on the vehicle speed during deceleration and the transmission gear ratio, as a torque equivalent to the engine brake. The vehicle deceleration energy recovery device according to claim 4 or 5, characterized in that

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