JPH1014010A - Hybrid vehicle power generation control device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent deterioration of a battery without damaging regenerative power even when regenerative power is generated from a motor. When a motor is in a regenerative state, a maximum regenerative electric energy is read from a maximum regenerative electric energy calculator (step S160). Next, the power generation amount is controlled such that the sum of the maximum regenerative power amount and the power generation amount of the generator 2 becomes the allowable charging power amount which is the output of the battery allowable charging power calculation unit 10 as shown in Expression 1. By subtracting the maximum regenerative electric energy read in step S160 from the allowable charge electric energy of the battery 3,
Calculate the power generation. Further, the duty ratio of the field current of the generator 2 corresponding to the generated power is calculated (step S17).
0). The control of the duty ratio of the field current and the constant speed control for controlling the fluctuation of the end rotation speed to a predetermined rotation speed due to the fluctuation of the driving torque of the generator 2 are simultaneously executed by the power generation unit controller 9. (Step S180).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power generation control device for a hybrid vehicle, and more particularly to a power generation control device for a hybrid vehicle capable of preventing deterioration of battery characteristics during regeneration.

[0002]

2. Description of the Related Art In general, a hybrid vehicle supplies an output of a generator driven by an engine or an output of a battery to a motor to drive wheels.
When the vehicle decelerates, the battery can be charged with the regenerative electric power by controlling the motor in a regenerative state. As such a hybrid electric vehicle, Japanese Patent Application Laid-Open No. 7-2
Japanese Patent Application Publication No. 36203 discloses an "electric vehicle control device". The hybrid vehicle detects the accelerator depression amount, the brake depression amount, the driving state of the motor 5 (power running, stop or regeneration), etc., using a plurality of sensors, and runs the hybrid vehicle as desired by the driver based on this information. The motor is driven from the inverter in order to perform the operation.

[0003] Specifically, when the motor is in a regenerative state, control is continued in such a manner that the amount of power generated does not impair the braking force in accordance with the amount of regenerative electric power. That is, when the motor is in the regenerative state, the power generation amount decreases when the regenerative power amount increases, and the power generation amount increases when the regenerative power amount decreases. As a result, even during regeneration, control can be performed so that the sum of the regenerative electric power and the generated electric power does not exceed the appropriate charge acceptance value of the battery, so that the battery can be prevented from being deteriorated and the electric power generation can be controlled. Therefore, the braking force due to regeneration is not impaired.

[0004]

When the regenerative power rises at the time when the regenerative power from the motor is generated, the amount of the power generation is adjusted so that the sum of the regenerative power and the power generation of the generator becomes an appropriate value for charging and receiving. Perform control. In this case, it is possible to control the torque of the generator in accordance with the response of the regenerative electric power. However, in general, in an ordinary engine vehicle, the response of the engine output torque is several hundred ms, whereas the braking force of the brake is required to be several tens of ms. It can be considered that the response of the engine output torque is determined by the response of the amount of air flowing into the cylinder. Furthermore, the response of the inflow air amount is governed not by the response of the throttle but by the dynamics of the intake system, so that only a very slow response to the brake can be realized.

Therefore, it is difficult to control the engine torque with the same responsiveness as the generator torque, so that the engine speed cannot be controlled to a predetermined speed and the power generation amount of the generator cannot be controlled. Will be. On the other hand, when the regenerative power rises at the time when the regenerative power returns to 0 again, the engine speed cannot be controlled in the same manner, so that the power for charging the battery falls below an appropriate value for a certain time.

As described above, the conventional hybrid vehicle control device attempts to make the engine follow the responsiveness when the regenerative electric energy changes, so that the charging power that transiently exceeds the appropriate value for accepting the charge of the battery is generated. Since the battery was added to the battery, it was a cause of deterioration of the battery. The present invention has been made in view of the above, and an object of the present invention is to prevent the deterioration of a battery without impairing regenerative power even when regenerative power is generated from a motor.

[0007]

According to the first aspect of the present invention,
In order to solve the above-mentioned problems, traveling information detecting means for detecting traveling information of the own vehicle, battery state detecting means for detecting a state of charge and a temperature state of a battery, and a battery based on a state of charge and a temperature state of the battery Means for calculating the allowable charging power of the motor, maximum regenerative power calculating means for calculating the maximum regenerative power of the motor, and regenerative power limiting means for limiting the regenerative power of the motor to the maximum regenerative power And a power generation control means for controlling the engine and the generator for driving the generator based on the permissible charging power, and the maximum regenerative power, and the maximum power generated from the generator and the maximum power from the motor. The gist is that the power generation amount is controlled by the power generation amount control means so that the sum with the regenerative power amount becomes the allowable charging power amount.

According to a second aspect of the present invention, in order to solve the above-mentioned problem, the maximum regenerative electric energy calculating means calculates a maximum regenerative electric energy by setting a deceleration within a predetermined range.

According to a third aspect of the present invention, in order to solve the above problems, the power generation amount control means controls the torque and efficiency of the generator and corrects the power generation amount in a variable range of the efficiency. And

[0010]

According to the first aspect of the present invention, the maximum value of the regenerative power is calculated in advance, and the sum of the maximum regenerative power and the power generation of the generator corresponds to the allowable charging power of the battery. Therefore, it is not necessary to control the power generation amount of the generator in response to the fast response of the regenerative power, and as a result, the battery does not need to be charged more than the allowable charging power. Deterioration can be prevented.

According to the second aspect of the present invention, the maximum regenerative electric energy is calculated according to the deceleration within a predetermined range, so that the driver does not feel the sense of deceleration of the vehicle with or without regeneration. Since the value is set to a value, for example, even if the allowable charging power amount of the battery becomes 0 and regeneration cannot be performed, the difference in the behavior of the vehicle does not cause the driver to feel uneasy.

According to the third aspect of the present invention, the torque and the efficiency of the generator are controlled, and the power generation amount is corrected in a variable range of the efficiency, so that the response to the regenerative electric power is reduced. And the amount of power generation during non-regeneration can be increased by the variable range of the efficiency.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 is a diagram showing a system configuration of a power generation control device for a hybrid vehicle according to a first embodiment of the present invention. In the figure, a power generation control device of a hybrid vehicle includes an engine 1 for driving a generator 2,
Generator 2 driven by engine 1 to generate electric power
And a battery 3 that charges the electric power generated by the generator 2 and supplies electric power to the motor 5 via the inverter 6.
And a maximum regenerative electric energy calculator 4 for calculating the maximum regenerative electric energy
A motor 5 for running the vehicle, an inverter 6 for converting power supplied from the generator 2 and / or the battery 3 to three-phase AC power and supplying power to the motor 5, A driving control unit 7 that inputs driving information from a plurality of sensors (not shown) and controls the inverter 6 to drive the vehicle as desired by the driver;
A regenerative power limiting unit 8 that receives an output from the traveling control unit 7 and an output from the maximum regenerative electric energy calculating unit 4 and limits the regenerative electric power.
A battery state detector 9 for detecting the amount of charge and temperature of the battery 3, a battery allowable charge power calculator 10 for calculating a battery allowable charge power based on an output from the battery state detector 9, A power generation unit control unit 11 controls the power generation of the power generation unit including the engine 1 and the generator 2 based on the output from the regenerative power amount calculation unit 4 and the output from the battery allowable charge power amount calculation unit 10.

The power generation control device for a hybrid vehicle having the above-described configuration uses a plurality of sensors to depress an accelerator pedal, a brake pedal, and a driving state of a motor 5 (powering,
Stop or regeneration) and the like are detected, and the traveling control unit 7 drives the inverter 6 based on the information to drive the vehicle as desired by the driver. Since the above-described control technology of the motor 5 is already known, a detailed description of the operation will be omitted.

Next, the operation of the maximum regenerative electric energy calculation unit 4 will be described with reference to the flowchart shown in FIG. First, in step S10, a deceleration is selected such that the sense of deceleration of the vehicle, which changes depending on the presence or absence of the regenerative braking force, does not give the driver an uncomfortable feeling. In addition, as a deceleration that does not give an uncomfortable feeling, for example, 0.05 g may be selected. Step S
In step 20, the selected deceleration is converted into the regenerative torque of the motor 5 using vehicle specifications such as vehicle weight and gear ratio, and the maximum regenerative torque is calculated. Next, in step S30, the motor speed is read. Next, in step S40, the maximum regenerative torque is converted into the regenerative electric energy using the rotation speed, and the maximum regenerative electric energy is calculated.

Next, the operation of the regenerative power limiting section 8 shown in FIG. 1 will be described. The regenerative power limiting unit 8 limits the motor output torque command output from the traveling control unit 7 so as not to exceed the maximum regenerative torque output from the maximum regenerative power calculation unit 4.

Next, the operation of the power generation unit control section 11 will be described with reference to the flowchart shown in FIG. First, in step S110, the state of charge of the battery 3 is detected by the battery state detection unit 9. Next, step S120
Then, it is determined whether or not the charged amount is less than 50% of the full charge. If the charged amount is less than 50%, the process proceeds to step S130. If not, the process returns to step S110. In step S130, the engine 1 is started and the warm-up operation is performed at the idle speed for a predetermined time. The detection of the amount of stored power is performed by detecting the remaining capacity of the battery 3 as to how much energy remains. However, the detection of the amount of energy consumed from the full charge is performed. You may.

In step S140, the driving state (power running, stop or regeneration) of the motor 5 is read from the traveling control unit 7. In step S150, it is determined whether or not the motor 5 is in a regenerative state based on the information read in step S140. If the motor 5 is in the regenerative state, the process proceeds to step S160; otherwise, the process proceeds to step S190. The determination of the regenerative state of the motor 5 may be performed by detecting whether the travel control unit 7 has commanded the inverter 6 to perform a power running operation, a regenerative operation, or a stop command. When the motor 5 is in the regenerative state, the maximum regenerative electric energy is read from the maximum regenerative electric energy calculator 4 in step S160. Next, step S
At 170, the sum of the maximum regenerative power and the power generated by the generator 2 is

(Equation 1) As described above, the power generation amount is controlled so as to be the allowable charging power amount which is the output of the battery allowable charging power calculation unit 10. In this step, the maximum regenerative electric energy read in step S160 is subtracted from the allowable charge electric energy of the battery 3, and
Calculate the power generation. Also, the duty ratio of the field current of the generator 2 corresponding to the generated power is calculated.

In step S180, step S170
The control of the duty ratio of the field current obtained in step (1) and the constant speed control for controlling the fluctuation of the end rotation speed due to the fluctuation of the driving torque of the generator 2 to a predetermined rotation speed are performed by the power generation unit controller 9. Run at the same time.

As a result, when the motor 5 is in the regenerative state, the control is continued so as to generate the amount of power that does not impair the braking force in accordance with the amount of regenerative electric power. That is, when the motor 5 is in the regenerative state, the power generation amount decreases when the regenerative power amount increases, and the power generation amount increases when the regenerative power amount decreases.

On the other hand, if it is determined in step S150 that the motor 5 is not in the regenerative state, the process proceeds to step S190 in the quantitative power generation mode. Step S190, S20
At 0, S210, and S220, the generator 2 generates a constant power regardless of the power running power amount of the motor 5. First,
In step S190, the power generation unit control unit 11 performs constant speed rotation control for controlling the number of rotations of the engine 1 to a predetermined number of times, and supplies a predetermined field current to the generator 2. In step S200, as in step S120, the remaining capacity of battery 3 is detected. Next, in step S210, it is determined whether the remaining capacity of the battery 3 is 70% or more. When the remaining capacity of the battery 3 is less than 70%, the process returns to step S140, and when it is 70% or more, the process proceeds to step S220. In step S220,
The engine 1 is stopped by the power generation unit control unit 11, and the field current applied to the generator 2 is cut off from the power generation unit controller 9. As a result, even during regeneration, control can be performed so that the sum of the regenerative electric power and the generated electric energy does not exceed the appropriate charge acceptance value of the battery 3, so that deterioration of the battery 3 can be prevented. Further, since the amount of power generation is controlled, the braking force due to regeneration is not impaired.

Next, the state of control in this embodiment will be described with reference to a timing chart shown in FIG. FIG.
As shown in (b) to (d), the regenerative electric energy is limited by the maximum regenerative electric energy, and the engine 1 and the generator 2 on the side of the power generation unit are in the regenerative state between the times t1 and t2. Since there is no change in the control compared to the control during non-regeneration, FIG.
As shown in (a), even when the regenerative power changes, there is no influence due to the quick response. Therefore, as shown in FIG. 4E, the charging power of the battery 3 does not exceed the allowable charging power, and the battery 3 does not deteriorate. By the way, when the battery state changes and the allowable charging power changes, it is necessary to change the power generation amount of the generator 2. However, the control response of the intake air of the engine 1 is not changed without the battery state changing rapidly. Since it is much slower, there is no deviation from the target values of the rotation speed and the power generation amount.

It is also conceivable that the maximum regenerative electric energy calculation unit 4 does not consider the discomfort to the driver in the calculation method. For example, even if the maximum regenerative electric energy is calculated by the power generation unit control unit 11 according to the output from the battery allowable charge power calculation unit 10, it is possible to prevent the deterioration of the battery 3 as in the present embodiment. Is obtained. However, when the battery 3 is fully charged, or when the temperature of the battery 3 becomes too high, the allowable charging power may become zero. In this case, the regenerative electric energy is set to 0
And the braking force due to regeneration cannot be obtained. As a result, it is conceivable that the behavior of the vehicle changes when regeneration is performed, giving the driver a sense of discomfort, discomfort, and anxiety. Therefore, as an effect of the present embodiment, it goes without saying that the behavior of the vehicle is changed and the driver can be prevented from feeling uncomfortable, uncomfortable, and uneasy.

(Second Embodiment) FIG. 5 is a diagram showing a system configuration of a power generation control device for a hybrid vehicle according to a second embodiment of the present invention. The features are in the traveling control unit 7 and the power generation unit control unit 11, and will be described below. First, the travel control unit 7 receives travel information from a plurality of sensors (not shown) for detecting a travel state and controls the inverter 6 to travel the hybrid vehicle as desired by the driver. The regenerative power is output to

Next, the power generation unit control section 11 includes a maximum regenerative electric power calculating section 4 and a battery allowable charging electric power calculating section 10.
And a power generation unit control unit 11 that receives the output of the traveling control unit 7 and controls the power generation of the power generation unit including the engine 1 and the generator 2. Note that the power generation unit control unit 7 has an inverter function, and controls the torque and efficiency of the generator 2 by changing the reactive current of the generator 2. Its response is equivalent to the regenerative power of the motor 5.

Next, the operation of the power generation unit control section 11 will be described with reference to the flowchart shown in FIG. Note that this flowchart is substantially the same as that shown in FIG. 3, and therefore only the differences will be described. The feature is that step S3
60, step S370 and step S380, which will be described below. In step S150, the motor 5
Is in the regenerative state, first, in step S360,
The power generation unit controller 11 reads the maximum regenerative power from the maximum regenerative power calculator 4 and the regenerative power from the travel controller 7.

Next, in step S370, the allowable charging power, which is the output of the battery allowable charging power calculator 10,
A target engine speed and a target generator torque are calculated from the maximum regenerative electric energy and the variable minimum efficiency of the generator 2, and
The generator efficiency is calculated so that the power generation amount of the generator 2 does not exceed the allowable charging power amount. In this step,

(Equation 2) The target engine speed and the target generator torque are calculated so that Equation 2 holds. next,

(Equation 3) The generator efficiency is calculated so that Equation 3 holds. In step S380, the inverter for the generator is controlled according to the target generator torque and the generator efficiency obtained in step S370, and the engine 1 is controlled so as to reach the target engine speed.

Next, the control in this embodiment will be described with reference to the timing chart shown in FIG. FIG.
As shown in (d), by changing the amount of power generation between times t1 and t2, as shown in FIG. 7 (e), the charge power of the battery 3 does not exceed the allowable charge power. However, the generator torque and the engine speed have not changed. This is because the amount of power generation is changed according to the generator efficiency. Since the generator efficiency can be changed by controlling the inverter for the generator, FIG.
As shown in (a), it is possible to follow a fast response of the regenerative power of the motor 5. In addition, the power generation amount without regeneration can be increased by a factor of (variable maximum efficiency / variable minimum efficiency). Since the variable minimum efficiency increases the reactive current, it is limited by the capacity of the inverter for the generator and the capacity of the generator 2.

[Brief description of the drawings]

FIG. 1 is a diagram showing a system configuration of a power generation control device for a hybrid vehicle according to a first embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of a maximum regenerative electric energy calculation unit 4;

FIG. 3 is a flowchart for explaining the operation of the power generation unit control unit 11;

FIG. 4 is a timing chart for explaining a state of control in the first embodiment.

FIG. 5 is a diagram showing a system configuration of a power generation control device for a hybrid vehicle according to a second embodiment of the present invention.

FIG. 6 is a flowchart for explaining the operation of the power generation unit control unit 11;

FIG. 7 is a timing chart for explaining a state of control in the second embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 engine 2 generator 3 battery 4 maximum regenerative power calculation unit 5 motor 6 inverter 7 cruise control unit 8 regenerative power limiting unit 9 battery state detection unit 10 battery allowable charging power calculation unit 11 power generation unit control unit

Claims (3)

[Claims] 1. A traveling information detecting means for detecting traveling information of a host vehicle, a battery state detecting means for detecting a state of charge and a temperature state of a battery, and an allowance of a battery based on the state of charge and a state of temperature of the battery. An allowable charging power calculating means for calculating the charging power, a maximum regenerative power calculating means for calculating the maximum regenerative power of the motor, a regenerative power limiting means for limiting the regenerative power of the motor to the maximum regenerative power, An engine for driving the generator based on the permissible charging power and a maximum regenerative power, and a power generation control means for controlling the generator, wherein the power generated by the generator and the maximum regenerative power from the motor are provided. A power generation control device for a hybrid vehicle, wherein the power generation amount is controlled by a power generation amount control unit such that a sum of the power amount and the allowable charging power amount becomes an allowable charging power amount. 2. The power generation control device for a hybrid vehicle according to claim 1, wherein said maximum regenerative electric energy calculating means calculates a maximum regenerative electric energy by setting a deceleration within a predetermined range. 3. The power generation of a hybrid vehicle according to claim 1, wherein said power generation amount control means controls a torque and an efficiency of a generator and corrects a power generation amount in a variable range of the efficiency. Control device.