JPH08308016A - Generator for hybrid vehicle - Google Patents

Abstract

PURPOSE: To provide the generator for a hybrid vehicle in which the generating output of the generator can be enhanced without supplying excess voltage to a battery and an on-vehicle electric component using the battery as its power source while obtaining the regenerative brake force of a traveling motor and which can effectively generate corresponding to the power consumption of the battery. CONSTITUTION: The generator for a hybrid vehicle comprises a target generating amount setter 19 for setting the value obtained by subtracting the dynamically generating amount of a traveling motor 2 from a predetermined reference generating amount of the allowable voltage supply amount or less of a battery 1 and an on-vehicle electric component 3 using the battery 1 as a power source at the time of regeneratively braking of the motor 2, as the target generating amount of the generator 6, and a target number-of-revolutions setter 20 for setting the target number of revolutions of the engine 5 from the amount 19, wherein the engine 5 and the generator 6 are controlled according to the target generating amount and the target number of revolutions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power generator for a hybrid vehicle.

[0002]

2. Description of the Related Art In an electric vehicle that is driven by the driving force of a running electric motor that uses a battery as a power source, the vehicle is equipped with a generator that uses an engine as a drive source, and the power output of the generator is the battery and this. There is known a so-called hybrid vehicle that charges the battery or suppresses power consumption of the battery by supplying power to various vehicle-mounted electric components using the power source as a power source. Then, in this type of hybrid vehicle, the engine and the generator are controlled so that the generator generates power at a constant power output, or a power output corresponding to the running driving force of the vehicle accompanied by battery power consumption is generated. Engines and generators are being controlled to tighten them.

On the other hand, in an electric vehicle including this kind of hybrid vehicle, regenerative braking of a traveling electric motor is usually performed when decelerating or braking during traveling, and the regenerative power generation output is recovered in a battery. Has been done. Therefore,
In such a hybrid vehicle that performs regenerative braking of the traveling electric motor, only the power output of the generator is supplied to the battery or the like when the traveling electric motor is driven, while the generator is used during regenerative braking of the traveling electric motor. Not only the power output of
The regenerative power output of the traveling electric motor is also supplied to the battery or the like.

On the other hand, if power is supplied to the battery or the on-vehicle electrical equipment exceeding the allowable power supply amount, the battery or the on-vehicle electrical equipment may be deteriorated or damaged.

Therefore, in the conventional hybrid vehicle, the power generation output of the generator is suppressed to a low level in consideration of the power generation output of the traveling electric motor during regenerative braking, and the amount of power supplied to the battery or the like is thereby reduced. Even when the electric motor for traveling is regeneratively braked, the allowable power supply amount of the battery or the like is not exceeded.

However, since the power generation output of the generator is suppressed to a low level in this way, the amount of power supplied to the battery or the like tends to become insufficient when driving the traveling electric motor, which consumes power, so that the battery is charged and its power is consumed. There is an inconvenience that the consumption cannot be suppressed efficiently and sufficiently.

In this case, in order to increase the power generation output of the generator, it is conceivable to make the regenerative power generation output by the regenerative braking of the traveling electric motor as small as possible, but the regenerative braking force of the traveling electric motor is However, it is not preferable because it affects the braking force of the vehicle.

[0008]

SUMMARY OF THE INVENTION In view of the above background, the present invention secures the regenerative braking force of a traveling electric motor and generates electric power from a generator without excessive power supply to a battery or vehicle-mounted electric equipment using the battery as a power source. An object of the present invention is to provide a power generation device for a hybrid vehicle capable of achieving high output and capable of performing accurate power generation corresponding to battery power consumption.

[0009]

In order to achieve the above object, the present invention travels by the driving force of a traveling electric motor using a battery as a power source and regenerative braking of the traveling electric motor during deceleration or braking during the traveling. In a power generator of a hybrid vehicle in which a generator that uses an engine as a drive source is mounted on a vehicle that performs the above-mentioned operation, and a power output of the generator is supplied to the battery and vehicle-mounted electrical equipment that uses the battery as a power source, During regenerative braking, the regenerative power generation amount of the traveling electric motor was subtracted from the reference power generation amount of the generator that was previously determined to supply power to the battery and the vehicle electrical device below the allowable power supply amount of the battery and the vehicle electrical component. Target power generation amount setting means for obtaining a value as the target power generation amount of the generator, and the generator power generation with the target power generation amount calculated by the target power generation amount setting means. Characterized in that a power generation control means for controlling the engine and the generator in order.

The reference power generation amount is set in accordance with the vehicle speed such that the higher the vehicle speed of the hybrid vehicle is, the target power generation amount setting means is such that at least the electric power consumption of the traveling electric motor is substantially constant. It is characterized in that the reference power generation amount is obtained as the target power generation amount when the traveling electric motor is driven during constant speed traveling.

Further, the target power generation amount setting means increases or decreases the reference power generation amount according to the power consumption amount of the traveling electric motor at the time of driving the traveling electric motor or less, within the allowable electric power supply amount of the battery and the vehicle-mounted electric components. It is characterized in that the power generation amount obtained by the above is calculated as the target power generation amount.

Further, the power generation control means obtains a target rotation speed of the engine for causing the generator to generate power at the target power generation amount obtained by the target power generation amount setting means, according to the target power generation amount. And controlling the engine so as to operate the engine at the obtained target rotation speed.

[0013]

According to the present invention, during regenerative braking of the traveling electric motor, the target electric power generation amount setting means changes the reference electric power generation amount of the generator from the reference electric power generation amount less than the permissible electric power supply amount of the battery and the on-vehicle electric components. A value obtained by subtracting the regenerative power generation amount is obtained as the target power generation amount of the generator, and at this time, since the engine and the generator are controlled by the power generation control unit so that the generator is generated at the target power generation amount, The sum of the power generation output of the generator and the regenerative power generation output of the traveling electric motor becomes the reference power generation amount, which is supplied to the battery and the vehicle-mounted electrical components. Therefore, the amount of power supplied to the battery and the on-vehicle electrical equipment does not exceed the allowable amount of power supply, and the amount of regenerative power generated by the traveling electric motor is maintained as it is.

In this case, the reference amount of power generation is determined in accordance with the vehicle speed so that it becomes larger as the vehicle speed of the hybrid vehicle increases, and at least during constant speed running at which the power consumption of the running electric motor is substantially constant. When the traveling electric motor is driven, the reference electric power generation amount corresponding to the vehicle speed is obtained as the target electric power generation amount, so that when the traveling electric motor is driven, the vehicle speed increases and the battery power consumption increases. As a result, the generator generates power with a large target power generation amount, and the power supply to the battery or the like is properly performed. Then, for example, when regenerative braking of the traveling motor is performed for decelerating or braking the vehicle from the constant speed traveling state of the hybrid vehicle, the sum of the power generation amount of the generator and the regenerative power generation amount of the traveling motor is Since the power generation amount of the generator is controlled so that the reference power generation amount corresponding to the vehicle speed at that time is controlled, the power supply to the battery or the like is appropriately maintained below the allowable power supply amount.

Further, when the traveling electric motor is driven, the target electric power generation amount is obtained by increasing or decreasing the reference electric power generation amount in accordance with the electric power consumption amount of the traveling electric motor at or below the allowable electric power supply amount of the battery and the on-vehicle electric components. When calculating the amount of power generation, even when the amount of power consumption of the battery is large, for example, when the vehicle accelerates, the amount of power generation that is commensurate with the amount of power consumption of the battery within the allowable power supply amount It is possible to generate power from the machine and power the battery.

Further, the power generation control means is provided with means for obtaining a target rotation speed of the engine for causing the generator to generate power at the target power generation amount in accordance with the target power generation amount. When the engine is operated, the target rotation speed is determined based on the load of the engine. Therefore, for example, the drive state of the traveling electric motor is changed to the regenerative braking state, and the power generation amount of the generator is When reducing the regenerative power generation amount of the traveling electric motor with respect to the reference power generation amount, the engine speed is controlled according to the reduction of the engine load due to the reduction of the power generation amount. As a result, the engine speed is controlled by a stable behavior change without causing the engine speed to rise.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. 1 is a system configuration diagram of a hybrid vehicle equipped with the power generator of this embodiment, FIG. 2 is a diagram for explaining the operation of the hybrid vehicle of FIG. 1, and FIG. 3 is a target of the power generator of the hybrid vehicle of FIG. FIG. 4 is a diagram showing a map for obtaining the amount of power generation, and FIG. 4 is a diagram showing an operating state of the power generation device when the hybrid vehicle of FIG. 1 is running.

Referring to FIG. 1, a hybrid vehicle A according to the present embodiment includes a battery 1, a traveling motor 2 (traveling electric motor) having the battery 1 as a power source, and an on-vehicle electrical component having the battery 1 as a power source. 3, a travel control device 4 that controls the drive of the travel motor 2, and a power generation device 7 that includes a generator 6 (generator) that uses an engine 5 as a drive source.

The battery 1 and the traveling motor 2 are connected to each other via a motor power supply controller 8 including an inverter circuit for controlling the amount of power supply between them.

The traveling motor 2 is connected to a pair of drive wheels 10, 10 of the hybrid vehicle A via a transmission 9, and the driving force is transmitted to the drive wheels 10, 10 via the transmission 9 to drive the hybrid vehicle A. Let it run.

The traveling control device 4 is composed of a microcomputer or the like, and the traveling control device 4 includes an accelerator sensor 11 for detecting an accelerator operation amount A.
And a brake switch 12 for detecting a brake operation,
Detection signals are input from the vehicle speed sensor 13 that detects the vehicle speed VCAR. Then, the traveling control device 4 basically controls the electric power supply from the battery 1 to the traveling motor 2 so that the traveling motor 2 can generate a driving force corresponding to the accelerator operation amount A and the vehicle speed VCAR. It is controlled via the unit 8.

Further, the travel control device 4 operates the motor when the brake switch 12 detects that the brake operation is performed or when the accelerator operation amount A obtained from the accelerator sensor 11 is decreased. Regenerative braking of the traveling motor 2 is performed via the power supply control unit 8, and the power generation output of the traveling motor 2 due to the regenerative braking is supplied to the battery 1 and the vehicle-mounted electrical component 3 via the motor power supply control unit 8. In this case, the traveling control device 4 performs the regenerative braking of the traveling motor 2 so that the regenerative power generation amount of the traveling motor 2 becomes the amount of power generation corresponding to the vehicle speed VCAR, as indicated by the solid line a in FIG. The larger the vehicle speed VCAR, the greater the amount of regenerative power generated. Therefore, the higher the vehicle speed VCAR,
The braking force during regenerative braking becomes stronger.

It should be noted that the traveling control device 4 includes a vehicle speed sensor 13
The vehicle speed VCAR obtained from the above, a signal indicating that during regenerative braking of the traveling motor 2, and the like are output to the power generation management device 15 of the power generation device 7 described later.

The power generator 7 includes, in addition to the engine 5 and the generator 6, a generator power supply control section 14 including an inverter circuit for controlling the amount of power supplied from the generator 6 to the battery 1 and vehicle-mounted electrical components 3, A power generation management device 15 that comprehensively manages and controls the operation of the engine 5 and the generator 6 at the time, and an engine controller 1 that controls the operation of the engine 5 according to an instruction from the power generation management device 15.
6 (hereinafter referred to as ECU 16) and a generator controller 17 (hereinafter referred to as GCU 17) that controls the operation of the generator 6 via the generator power feeding control unit 14 according to an instruction from the power generation management device 15. The generator 6 is connected to a crankshaft (not shown) of the engine 5.

Power generation management device 15, ECU 16 and GCU
Reference numeral 17 denotes a microcomputer or the like, and the power generation management device 15 includes a vehicle speed VCAR detected by the vehicle speed sensor 13 from the travel control device 4.
Is input and the detection signal of the motor power detector 18 for detecting the power consumption PM of the traveling motor 2 based on the energization current and the energization voltage of the traveling motor 2 detected by a current sensor or a voltage sensor (not shown). Is entered.
The power generation management device 15 has, as its functional configuration,
Given vehicle speed VCAR and power consumption PM of traveling motor 2
A target power generation amount setting unit 19 (target power generation amount setting means) for obtaining a target power generation amount of the generator 6 based on the above, and an engine 5 required for causing the generator 6 to generate power with the target power generation amount.
And a target rotation speed setting unit 20 that obtains a target rotation speed of
The target power generation amount and the target speed are calculated by the ECU 16 and the GC.
Instruct U17.

In this case, the ECU 16 controls the power generation management device 1
Based on the target power generation amount and the target rotation speed instructed from 5, the throttle operation amount of the engine 5 for operating the engine 5 at the target rotation speed is determined according to a predetermined arithmetic expression,
According to the determined throttle operation amount, the throttle operation of the engine 5 is performed via an actuator (not shown).

Further, the GCU 17 is for performing the power supply from the generator 6 to the battery 1 or the like at the target power generation amount based on the target power generation amount or the target rotation speed instructed from the power generation management device 15 according to a predetermined arithmetic expression or the like. The power supply amount of the generator 6 is determined, and the power supply control of the generator 6 is performed via the generator power supply control unit 14 according to the determined power supply amount.

Incidentally, corresponding to the configuration of the present invention, the power generation management device 15, the ECU 16 and the GCU 17 are the power generation control means 2
1 constitutes one.

Next, the operation of the power generator 7 of the hybrid vehicle A of this embodiment will be described.

When the hybrid vehicle A is traveling, the target power generation amount setting unit 19 of the power generation management device 15 determines from the vehicle speed VCAR and the power consumption PM of the traveling motor 2 provided from the traveling control device 4 and the motor power detector 18, respectively. The target power generation amount is calculated according to a predetermined map shown in FIG.

Here, in the map of FIG. 3, the positive power consumption PM indicates the power consumption when the traveling motor 2 is driven, and the negative power consumption PM indicates the regenerative braking of the traveling motor 2. Power consumption at that time, that is, the amount of regenerative power generation. In the map shown in FIG. 3, basically, the target power generation amount is set such that the target power generation amount increases as the vehicle speed VCAR increases, and in particular, the constant speed of the hybrid vehicle A driven by the drive motor 2 is set. The target power generation amount during traveling (at this time, the power consumption PM of the traveling motor 2 is determined to be a certain positive value corresponding to the vehicle speed VCAR) has a characteristic as shown by the solid line b in FIG. 2 according to the vehicle speed VCAR. It is set. Here, the solid line b in FIG. 2 indicates the reference power generation amount of the generator 6, and the reference power generation amount is used for the traveling motor 2 at the constant speed traveling at each vehicle speed VCAR accompanied by the power consumption of the traveling motor 2. The power generation amount of the generator 6 is set so as to supply power to the battery 1 commensurate with the power consumption PM of 1 while not exceeding the allowable power supply amount (rated value) of the battery 1 and the vehicle-mounted electrical component 3.

Further, in the map of FIG. 3, each vehicle speed VCA
The target power generation amount at various power consumption PW of the traveling motor 2 at R is set to a value within the allowable power supply amount of the battery 1 or the like by increasing or decreasing the reference power generation amount according to the power consumption PM. Specifically, it is set such that the larger the power consumption PM is with a positive value, the larger. Then, in particular, during regenerative braking when the power consumption PM of the traveling motor 2 becomes a negative value, the target power generation amount at each vehicle speed VCAR is calculated from the reference power generation amount indicated by the solid line b in FIG. 2 corresponding to the vehicle speed VCAR. , A value obtained by subtracting the regenerative power generation amount of the traveling motor 2 shown by the solid line a in the figure corresponding to the vehicle speed VCAR is determined.

In the power generation management device 15 which has obtained the target power generation amount according to such a map, the target rotation speed setting unit 20 obtains the target rotation speed of the engine 5 from the target power generation amount according to the table shown in Table 1 below.

[0034]

[Table 1]

In this case, the target rotation speed in the table of Table 1 is predetermined as the rotation speed of the engine 5 capable of operating the engine 5 with the output corresponding to the target power generation amount.

The power generation management device 15, which has obtained the target power generation amount and the target rotation speed as described above, outputs the target power generation amount and the target rotation speed to the ECU 16 and the GCU 17.

At this time, as described above, the ECU 16
The throttle operation amount of the engine 5 is determined from the target power generation amount and the target rotation speed according to a predetermined arithmetic expression, etc., and the throttle operation of the engine 5 is performed via an actuator (not shown) according to the determined throttle operation amount. As a result, the rotation speed of the engine 5 is controlled to the target rotation speed.

Further, the GCU 17 determines the energization amount of the generator 6 from the target power generation amount and the target rotation speed according to a predetermined arithmetic expression and the like, and controls the energization of the generator 6 according to the determined energization amount. Through. As a result, the generator 6 generates power with the target amount of power generation by driving the engine 5 controlled to the target rotation speed, and supplies the power generation output to the battery 1 and the vehicle-mounted electrical component 3.

By controlling the power generator 7 as described above, for example, when the hybrid vehicle A is traveling at a constant speed by driving the traveling motor 2 or when accelerating, the generator 6 causes the vehicle speed VCAR and the traveling motor 2 for accelerating. The power generation amount corresponding to the increase in the power consumption of the battery 1 and the power generation amount within the allowable power supply amount of the battery 1 or the like are generated, and the power generation output is supplied to the battery 1 or the like.
Is efficiently and properly charged according to the power consumption based on the driving of the traveling electric motor 2, and the battery 1 or the like is not supplied with power exceeding its allowable power supply amount.

Further, for example, when regenerative braking of the traveling motor 2 is performed from the constant speed traveling state in which the generator 6 is generating power with the reference amount of electricity generated, the amount of power generated by the generator 6 is equal to that of the traveling motor. Since the sum of the regenerative power generation amount of 2 and the reference power generation amount is controlled, the battery 1
Etc. are continuously supplied with an appropriate amount of power supply corresponding to the vehicle speed VCAR within the allowable amount of power supply, the battery 1 is efficiently charged, and excessive power is supplied to the battery 1 etc. Nothing.

In this case, the power generation amount of the generator 6 is reduced by the amount of regenerative power generation as compared to when the traveling motor 2 is driven, and the load of the engine 5 is reduced. Since the rotation speed corresponding to the amount of power generation of the corresponding generator 6 is controlled as the target rotation speed,
The engine 5 is stably operated without the engine 5 being blown up due to the reduction of the load of the engine 5. Therefore, good exhaust performance and vibration performance of the engine 5 can be secured.

FIG. 4 shows an operating condition of the power generator 7 when the hybrid vehicle A of this embodiment is actually driven. FIG.
FIG. 4A is a diagram showing how the vehicle speed VCAR changes.
(B) ~ (d) is a diagram showing the power consumption PM of the traveling motor 2, the amount of power generation of the generator 6 and the rotation speed of the engine 5 during traveling, respectively.

As can be seen from these FIG. 4, the power generation amount of the generator 6 and the rotation speed of the engine 5 are approximately the vehicle speed VCAR.
Changes so as to follow the changes in. Then, during regenerative braking in which the power consumption PM of the traveling motor 2 becomes negative (vehicle speed V
The power generation amount of the generator 6 (when CAR decreases) immediately decreases as the power consumption PM of the traveling motor 2 increases to the negative side. Further, at this time, the rotation speed of the engine 5 decreases in accordance with the decrease in the power generation amount of the generator 6 without causing the engine to blow up.

[0044]

As is apparent from the above description, according to the present invention, during regenerative braking of the traveling electric motor, the traveling electric motor is driven from the reference electric power generation amount of the generator less than the allowable power supply amount of the battery and the vehicle-mounted electric components. The value obtained by subtracting the regenerative power generation amount is obtained as the target power generation amount of the generator, and by controlling the engine and the generator according to the target power generation amount, it is possible to secure the battery and it while securing the regenerative braking force of the traveling electric motor. It is possible to generate power from the generator without excessively supplying power to the vehicle-mounted electrical equipment that is used as a power source. Therefore, it is possible to increase the power generation output of the generator when the traveling electric motor is driven.

Then, the reference power generation amount is determined in accordance with the vehicle speed so that it becomes larger as the vehicle speed of the hybrid vehicle increases, and at least the electric power consumption of the electric motor for traveling is substantially constant during the constant speed traveling. When the driving electric motor is driven, the reference electric power generation amount corresponding to the vehicle speed is calculated as the target electric power generation amount when driving the vehicle. Of the battery and the like, the generator can generate power with an amount of power generation that is less than or equal to the allowable power supply amount of the battery, and further, even when the regenerative braking of the traveling electric motor is performed during traveling of such a hybrid vehicle, the battery, etc. The total amount of power supplied to the motor can be maintained at the same level as the amount of power supplied when the traveling electric motor is driven.

Further, when the traveling electric motor is driven, the amount of electric power generated by increasing / decreasing the reference electric power generation amount in accordance with the electric power consumption amount of the traveling electric motor is set as the target electric power generation amount, which is equal to or less than the allowable electric power supply amount of the battery and the on-vehicle electric components. By requesting, the generator can generate power with an accurate power generation output commensurate with the power consumption of the battery even when the hybrid vehicle is accelerating, etc. Therefore, the battery corresponds to the power consumption state of the traveling electric motor. It can be charged efficiently with an appropriate amount of power generation.

Further, the target rotation speed of the engine for causing the generator to generate power with the obtained target power generation amount is obtained according to the target power generation amount, and the engine is controlled to operate at the target rotation speed. In the case where the power generation amount of the generator suddenly changes and the load of the engine suddenly changes, such as when the traveling electric motor shifts from the driving state to the regenerative braking state and the power generation amount of the generator decreases, It is possible to operate stably without causing blow-up in accordance with changes in load, and it is possible to improve the exhaust performance and vibration performance of the engine.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of a hybrid vehicle including a power generation device according to an example of the present invention.

FIG. 2 is a diagram for explaining the operation of the power generator of the hybrid vehicle of FIG.

FIG. 3 is a diagram showing a map for obtaining a target power generation amount of the power generator of the hybrid vehicle of FIG.

FIG. 4 is a diagram showing an operating condition of the power generator when the hybrid vehicle of FIG. 1 is running.

[Explanation of symbols]

A ... Hybrid vehicle, 1 ... Battery, 2 ... Running electric motor, 3 ... In-vehicle electrical equipment, 5 ... Engine, 6 ... Generator, 7 ...
Power generation device, 19 ... Target power generation amount setting means, 20 ... Target rotation speed setting means, 21 ... Power generation control means.

Claims (4)

[Claims] 1. A generator having an engine as a drive source is mounted on a vehicle that is driven by a driving force of a traveling electric motor using a battery as a power source and regeneratively brakes the traveling electric motor during deceleration or braking during the traveling. However, in a power generator of a hybrid vehicle that supplies the power output of the generator to the battery and an in-vehicle electrical component that uses the battery as a power source, an allowable power supply amount of the battery and the in-vehicle electrical component during regenerative braking of the traveling motor. A target power generation amount setting which is obtained as a target power generation amount of the generator by subtracting a regenerative power generation amount of the traveling electric motor from a reference power generation amount of the power generator predetermined to supply power to the battery and in-vehicle electrical equipment Means, and power generation control means for controlling the engine and the generator so as to generate power by the target power generation amount obtained by the target power generation amount setting means. Power generator of the hybrid vehicle, characterized by comprising. 2. The reference power generation amount is set in accordance with the vehicle speed such that the reference power generation amount increases as the vehicle speed of the hybrid vehicle increases, and the target power generation amount setting means has at least a substantially constant power consumption amount of the traveling electric motor. 2. The power generation device for a hybrid vehicle according to claim 1, wherein the reference power generation amount is obtained as the target power generation amount when the traveling electric motor is driven during constant speed traveling. 3. The target power generation amount setting means increases or decreases the reference power generation amount in accordance with the power consumption amount of the traveling electric motor when the traveling electric motor is driven, at a power supply amount less than or equal to an allowable power supply amount of the battery and vehicle-mounted electric components. The power generation device for a hybrid vehicle according to claim 2, wherein the power generation amount obtained is obtained as the target power generation amount. 4. The power generation control means obtains a target rotation speed of the engine for causing the generator to generate power at the target power generation amount obtained by the target power generation amount setting means, according to the target power generation amount. 4. The power generation device for a hybrid vehicle according to claim 1, further comprising: a control unit configured to control the engine so as to operate the engine at the obtained target rotation speed.