JP2021133722A - Charging control device - Google Patents

Abstract

To provide a charging control device capable of performing charging control to prevent a charging amount from exceeding allowable input power of a power storage device.SOLUTION: An on-vehicle charging control device comprises: an electric rotating machine which generates driving force to drive a wheel; a power storage device which stores electric power to be supplied to the electric rotating machine; a generator which generates electric power to charge the power storage device; and an engine which generates driving force to drive the generator. When electric power available for power supply to the power storage device is equal to or less than a predetermined value and power supply to the power storage device through power regeneration with the electric rotating machine is performed concurrently with the power supply thereto through power generation with the generator, the on-vehicle charging control device controls electric power to be supplied to the power storage device through the power regeneration with the electric rotating machine while giving a priority to the power supply to the power storage device through the power generation with the generator in response to a predetermined change in a vehicle state which increases required regenerative power generation.SELECTED DRAWING: Figure 6

Description

The present invention relates to a charge control device.

Patent Document 1 describes driving in a control device for a hybrid vehicle including an engine, a battery, a power generation motor connected to an output shaft of the engine, and a drive motor connected to a drive shaft connected to drive wheels. When the regenerative power of the motor exceeds the upper limit of the charging power of the battery (allowable input power amount), the power generation motor is driven by the difference value between the regenerative power of the drive motor and the upper limit of the charging power of the battery. A technique for driving an engine by doing so and consuming a surplus of regenerative power is disclosed.

JP-A-2019-151305

In the case of a so-called series hybrid vehicle that runs by supplying power from at least one of a generator and a battery to drive a drive motor without using the engine as a driving force source for running, a predetermined value that increases the regeneration requirement. It is desirable to control the charging of the battery more appropriately so that the amount of power input to the battery does not exceed the allowable input power when there is a change in the vehicle condition, as compared with the technique disclosed in Patent Document 1. Is done.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a charge control device capable of performing charge control that does not exceed the allowable input power of the power storage device.

In order to solve the above-mentioned problems and achieve the object, the charge control device according to the present invention includes a rotary electric machine that generates a driving force for driving wheels, a power storage device that stores electric power supplied to the rotary electric machine, and the like. A charge control device mounted on a vehicle including a generator for generating electric power for charging the power storage device and an engine for generating a driving force for driving the generator, which can be supplied to the power storage device. When the amount of electric power is equal to or less than a predetermined value, and when the electric power supply to the electric power storage device by the regeneration of the rotary electric electric machine and the electric power supply to the electric power storage device by the power generation of the generator are performed at the same time, the regeneration request increases. When there is a change in a predetermined vehicle condition, the power supplied to the power storage device by the regeneration of the rotary electric machine is adjusted while giving priority to the power supply to the power storage device by the power generation of the generator. It is characterized by performing.

The charge control device according to the present invention gives priority to the power supply to the power storage device by the power generation of the generator when there is a predetermined change in the vehicle condition such that the regenerative demand increases, and the power storage device by the regeneration of the regenerative electric machine. By adjusting the power supplied to the power storage device, it is possible to perform charge control that does not exceed the allowable input power of the power storage device.

FIG. 1 is a diagram showing a main configuration of a hybrid vehicle according to an embodiment. FIG. 2 is a diagram showing a calculation image of the power generation execution power and the regeneration execution power in the calculation formula A (power generation priority). FIG. 3 is a diagram showing a calculation image of the power generation execution power and the regeneration execution power in the calculation formula B (regeneration priority). FIG. 4 is a diagram showing a calculation image of the power generation execution power and the regeneration execution power according to the calculation formula C (no priority). FIG. 5 is a flowchart showing an example of battery charge control carried out by the HV-ECU in the hybrid vehicle according to the embodiment. FIG. 6 is a timing chart of battery charge control in the hybrid vehicle according to the embodiment.

Hereinafter, embodiments of the charge control device according to the present invention will be described. The present invention is not limited to the present embodiment.

FIG. 1 is a diagram showing a main configuration of the hybrid vehicle 1 according to the embodiment. The hybrid vehicle 1 according to the embodiment includes a drive motor 11, a drive motor ECU 12, a drive side PCU 13, a transformer axle 14, an engine 21, an engine ECU 22, a power generation motor 23, a power generation motor ECU 24, a power generation side PCU 25, a battery 31, a battery ECU 32, and a battery. It includes a temperature sensor 33, a power branch 34, an AC charging port 41, an AC charger 42, a DC charging port 51, an HV-ECU 61, a pair of wheel shafts 71, a pair of drive wheels 72, and the like.

The hybrid vehicle 1 according to the embodiment is a so-called series hybrid, in which the engine 21 is not used as a driving force source for traveling, but is used as a power source for the power generation motor 23, and the drive motor 11 is driven mainly by electric power from the battery 31. It has a structure of a traveling range extender.

The drive motor 11 is mechanically connected to the transaxle 14, and the driving force from the drive motor 11 is supplied to the transaxle 14. The driving force from the drive motor 11 supplied to the transaxle 14 is transmitted to the drive wheels 72, which are the front wheels, via the wheel shaft 71 as the drive power for traveling.

Further, the drive motor 11 is electrically connected to the drive side PCU 13. When the hybrid vehicle 1 decelerates, the drive motor 11 is driven by the rotation of the drive wheels 72, and the drive motor 11 functions as a generator. As a result, so-called regeneration is performed. When the drive motor 11 functions as a generator, the regenerative power (regenerative power) generated by the regeneration of the drive motor 11 is branched to the battery 31 side by the power branching portion 34 via the drive side PCU 13 and supplied to the battery 31. On the other hand, when the drive motor 11 functions as an electric motor, the electric power stored in the battery 31 is branched to the drive side PCU 13 side by the power branch portion 34 and supplied to the drive motor 11 via the drive side PCU 13.

The drive-side PCU 13 is provided with a drive motor ECU 12, an inverter, a boost converter, and the like. The drive motor ECU 12 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, a communication port, and the like, in addition to the CPU. .. Signals from various sensors necessary for driving and controlling the drive motor 11 are input to the drive motor ECU 12 via the input port. From the drive motor ECU 12, a switching control signal or the like to the switching element of the inverter provided in the drive side PCU 13 is output via the output port. The drive motor ECU 12 is connected to the HV-ECU 61 via a communication port, drives and controls the drive motor 11 by a control signal from the HV-ECU 61, and outputs data on the drive state of the drive motor 11 to the HV as needed. -Output to ECU 61.

The engine 21 is configured as an internal combustion engine that outputs power using gasoline, light oil, or the like as fuel. The operation of the engine 21 is controlled by the engine ECU 22, which is an electronic control unit for the engine.

The engine ECU 22 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, a communication port, and the like, in addition to the CPU. There is. Signals from various sensors necessary for controlling the operation of the engine 21 are input to the engine ECU 22 from the input port. From the engine ECU 22, various control signals for controlling the operation of the engine 2 are output via the output port. The engine ECU 22 is connected to the HV-ECU 61 via a communication port, controls the operation of the engine 21 by a control signal from the HV-ECU 61, and transmits data on the operating state of the engine 21 to the HV-ECU 61 as needed. Output.

The power generation motor 23 is mechanically connected to the engine 21, and the power generation motor 23 is driven by the driving force from the engine 21, and the power generation motor 23 functions as a generator. The power generation motor 23 is electrically connected to the power generation side PCU 25. The electric power generated by the power generation motor 23 is branched and supplied by the power branching portion 34 to at least one of the drive side PCU 13 and the battery 31 via the power generation side PCU 25.

The power generation side PCU 25 is provided with a power generation motor ECU 24, an inverter, a boost converter, and the like. The power generation motor ECU 24 is provided in the power generation side PCU 25 and is configured as a microprocessor centered on a CPU. In addition to the CPU, a ROM for storing a processing program, a RAM for temporarily storing data, and input / output. It is provided with a port, a communication port, and the like. Signals from various sensors necessary for driving and controlling the power generation motor 23 are input to the power generation motor ECU 24 via the input port. From the power generation motor ECU 24, a switching control signal or the like to the switching element of the inverter provided in the power generation side PCU 25 is output via the output port. The power generation motor ECU 24 is connected to the HV-ECU 61 via a communication port, drives and controls the power generation motor 23 by a control signal from the HV-ECU 61, and outputs data on the drive state of the power generation motor 23 to the HV as necessary. -Output to ECU 61.

The battery 31 can be charged by the generated power (generated power) supplied from the power generation motor 23 and the regenerative power (regenerated power) supplied from the drive motor 11. The battery 31 is, for example, a secondary battery such as a lithium ion battery or a nickel hydrogen battery.

Further, in the hybrid vehicle 1 according to the embodiment, the AC power supplied from the AC external power source via the AC charging port 41 is converted into DC power by the AC charger 42 to charge the battery 31 or the DC charging port 51. It is possible to charge the battery 31 with DC power supplied from a DC external power source via the above.

The battery ECU 32 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, a communication port, and the like, in addition to the CPU. There is. Signals from various sensors necessary for managing the battery 31 are input to the battery ECU 32 via the input port. The signals input to the battery ECU 32 include, for example, the battery voltage from the voltage sensor installed between the terminals of the battery 31, the battery current from the current sensor attached to the output terminal of the battery 31, and the battery 31 attached to the battery 31. Examples include the battery temperature from the battery temperature sensor 33. The battery ECU 32 is connected to the HV-ECU 61 via a communication port, and outputs data regarding the state of the battery 31 to the HV-ECU 61 as needed. The battery ECU 32 calculates the SOC (State of Charge) of the battery 31 based on the integrated value of the battery current from the current sensor. The SOC of the battery 31 is the ratio of the capacity of the electric power that can be discharged from the battery 31 to the total capacity of the battery 31. Further, the battery ECU 32 calculates the permissible input power Win and the permissible output power amount Wout, which are the maximum permissible power amounts of input and output in charging / discharging of the battery 31, based on the SOC of the battery 31 and the battery temperature.

The HV-ECU 61 is an electronic control device that controls the hybrid vehicle 1. The HV-ECU 61 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, a communication port, and the like, in addition to the CPU. ing. The HV-ECU 61 is electrically connected to the drive motor ECU 12, the engine ECU 22, the power generation motor ECU 24, the battery ECU 32, the AC charger 42, and the like, and controls them. Further, the outputs of various sensors provided in the hybrid vehicle 1 are input to the HV-ECU 61. For example, the HV-ECU 61 can calculate the front wheel speed, which is the rotational speed of the front wheels, based on the signal from the front wheel speed sensor attached to the drive wheels 72, which are the front wheels. Further, the HV-ECU 61 can calculate the rear wheel speed, which is the rotational speed of the rear wheels, based on the signal from the rear wheel speed sensor attached to the rear wheels. Further, in the hybrid vehicle 1 according to the embodiment, the HV-ECU 61 functions as a charge control device for controlling the charge of the battery 31.

Here, in the hybrid vehicle 1 according to the embodiment, regarding the charging of the battery 31, when the hybrid vehicle 1 is in the deceleration state, the maximum regenerative power is obtained from the drive motor 11 with respect to the allowable input power Win of the battery 31. It is desirable to charge the battery 31 with priority given to regeneration from the viewpoint of improving fuel efficiency. On the other hand, in the hybrid vehicle 1 according to the embodiment, it is possible to determine the amount of power generated by the power generation motor 23 regardless of the driver's drive request. Therefore, for example, when the battery 31 is in a low SOC state and it is desired to stably supply power to the battery 31 regardless of the change in the regenerative power from the drive motor 11, the power generated by the power generation motor 23 Is desired to be supplied to the battery 31 to charge the battery 31 with priority given to power generation by the power generation motor 23, and it is desirable to avoid the exhaustion of the SOC of the battery 31 as soon as possible.

However, as shown in Table 1 below, the regenerative power from the drive motor 11 fluctuates from moment to moment depending on the vehicle condition, vehicle behavior, road surface condition, and the like of the hybrid vehicle 1. Therefore, when charging the battery 31 with priority on regeneration by the drive motor 11, there is a possibility that sufficient regeneration power cannot be obtained with respect to the required battery charging power.

Further, since the amount of power generated by the power generation motor 23 is generated by driving the power generation motor 23 by the driving force from the engine 21, the responsiveness is not high enough to change according to the fluctuation of the regenerative power. Therefore, in charging the battery 31 with priority given to power generation by the power generation motor 23, the required battery charging power may exceed the allowable input power Win of the battery 31.

Therefore, the hybrid vehicle 1 according to the embodiment gives priority to regeneration by the drive motor 11 based on various determination conditions as shown in Table 1, for example, according to the vehicle condition, vehicle behavior, road surface condition, etc. of the hybrid vehicle 1. And the power generation priority by the power generation motor 23, the priority charging method of the battery 31 is selected. Then, in the hybrid vehicle 1 according to the embodiment, the balance between the charging of the battery 31 by the regeneration of the drive motor 11 and the charging of the battery 31 by the power generation of the power generation motor 23 is coordinated according to the traveling situation, so that the fuel efficiency is deteriorated. It is possible to quickly get out of the low SOC state of the battery 31 without exceeding the allowable input power Win of the battery 31 while minimizing the above.

FIG. 2 is a diagram showing a calculation image of the power generation execution power and the regeneration execution power in the calculation formula A (power generation priority). FIG. 3 is a diagram showing a calculation image of the power generation execution power and the regeneration execution power in the calculation formula B (regeneration priority). FIG. 4 is a diagram showing a calculation image of the power generation execution power and the regeneration execution power according to the calculation formula C (no priority).

In the hybrid vehicle 1 according to the embodiment, when the SOC of the battery 31 is limited to a predetermined value or less and the allowable input power Win of the battery 31 is limited to a predetermined value or less, the regeneration by the drive motor 11 and the power generation by the power generation motor 23 The following calculation formulas A, B, and C are used to calculate the power generation execution power that can be executed by the power generation motor 23 and the regeneration execution power that can be executed by the drive motor 11 in a situation in which Switch with. As a result, the power supply to the battery 31 can be stably executed regardless of the driver's deceleration request or the vehicle condition, so that the battery 31 can be quickly released from the low SOC state.

(Calculation formula A: Priority for power generation)
・ Power generation execution power = fixed to the minimum value MIN (basic power generation amount map when accelerator is off, allowable input power Win) ・ Regeneration execution power = 0 or “allowable input power Win-power generation execution power-predetermined margin”

(Calculation formula B: Regeneration priority)
・ Power generation execution power = basic power generation amount map when the accelerator is off is limited by “allowable input power Win-maximum regenerative power-predetermined margin” ・ Regeneration execution power = minimum value MIN (required regenerative torque based on driver's brake operation, Maximum regenerative power)

(Calculation formula C: No priority)
・ Power generation execution power = basic power generation amount map when the accelerator is off
・ Regenerative execution power = Required regenerative torque based on driver's brake operation

In the hybrid vehicle 1 according to the embodiment, as a basic state, the battery 31 is charged based on the idea of giving priority to regeneration by the drive motor 11. That is, the regenerative execution power is calculated from the deceleration based on the driver's braking operation. That is, the regenerative power fluctuates depending on the driver's braking force, the sharing of braking force with the hydraulic brake, the vehicle speed, and the like. Further, the power generation execution power is limited to the upper limit value by subtracting a predetermined margin and the maximum regenerative power from the allowable input power Win of the battery 31 based on the basic power generation amount map when the accelerator is off, which is created in advance. Here, the maximum regenerative power is assumed to indicate the maximum value of the required regenerative power. That is, the power generation execution power is limited to the power that does not exceed the allowable input power Win even if the maximum value of the required regenerative power is continuously taken.

Further, in the hybrid vehicle 1 according to the embodiment, each item of vehicle speed, shift position, air conditioner switch, front / rear wheel speed, power generation motor temperature, power generation side inverter temperature, drive motor temperature, drive side inverter temperature, and boost converter temperature When the states exceed the predetermined values, the battery 31 is charged based on the idea of giving priority to power generation. That is, as for the power generation execution power, power generation is continuously performed with the basic power generation amount map within a range in which the limit of the allowable input power Win can be observed. Basically, the regenerative execution power is set to 0, and the braking force is secured by the hydraulic brake. However, when the power generation execution power is sufficiently small with respect to the allowable input power Win (when the required power generation power is small due to a request such as NV or when the displacement of the engine 21 is small), it is based on the required power generation power at that time. It is also possible to determine the regenerative execution power by limiting the difference from the allowable input power Win to the upper limit value after securing a predetermined margin. That is, the regenerative execution power of the drive motor 11 fluctuates according to the power generation execution power of the power generation motor 23, not the required regenerative torque based on the driver's brake operation.

Further, in the hybrid vehicle 1 according to the embodiment, the accelerator is turned off according to the traveling situation by switching between charging the battery 31 with priority on regeneration by the drive motor 11 and charging the battery 31 with priority on power generation by the power generation motor 23. The breakdown of the regenerative power of the drive motor 11 and the generated power of the power generation motor 23 at the time and when the brake is turned on is variably controlled.

If neither of the conditions of charging the battery 31 with priority on regeneration and charging of the battery 31 with priority on power generation is met, there is little concern that the allowable input power Win will be exceeded or the battery SOC will be exhausted. Therefore, the battery 31 is charged without both regeneration priority and power generation priority (no priority). That is, the power generation execution power is determined by the basic power generation amount map when the accelerator is off. The regenerative execution power is determined from the required regenerative torque based on the driver's braking operation.

FIG. 5 is a flowchart showing an example of charge control of the battery 31 implemented by the HV-ECU 61 in the hybrid vehicle 1 according to the embodiment.

First, the HV-ECU 61 determines whether the battery SOC ≦ a predetermined value (step S1). When it is determined that the battery SOC ≦ the predetermined value (Yes in step S1), the HV-ECU 61 determines whether the allowable input power Win ≦ the predetermined value (step S2). When it is determined that the allowable input power Win ≦ a predetermined value (Yes in step S2), the HV-ECU 61 determines whether or not the power generation state is generated by the power generation motor 23 (step S3), and the power generation state is determined by the power generation motor 23. If it is determined that there is (Yes in step S3), the HV-ECU 61 determines whether the accelerator is OFF or the brake is ON (Step S4). When it is determined that the accelerator is OFF or the brake is ON (Yes in step S4), the HV-ECU 61 determines whether the power generation motor temperature ≥ a predetermined value (step S5). When it is determined that the power generation motor temperature ≥ the predetermined value (Yes in step S5), the HV-ECU 61 calculates the power generation execution power and the regeneration execution power using the calculation formula A and performs charge control (step). S6), the series of control is terminated.

Further, when the HV-ECU 61 determines that any of the determination conditions of steps S1 to S4 is not satisfied (No in step S1, No in step S2, No in step S3, or step S4). No), the power generation execution power and the regeneration execution power are calculated using the calculation formula C to perform charge control (step S12), and a series of controls is completed.

Further, when the HV-ECU 61 determines that the determination condition in step S5 is not satisfied (No in step S5), the HV-ECU 61 determines whether the boost converter temperature ≥ a predetermined value (step S7). When it is determined that the boost converter temperature ≥ the predetermined value (No in step S7), the HV-ECU 61 determines whether the difference between the front and rear wheel speeds ≥ the predetermined value (step S8). When it is determined that the difference between the front and rear wheel speeds is not equal to the predetermined value (No in step S8), the HV-ECU 61 determines whether the air conditioner is ON (step S9). When it is determined that the air conditioner is not ON (No in step S9), the HV-ECU 61 determines whether the D range and the vehicle speed ≥ the predetermined value (step S10). When it is determined that the D range and the vehicle speed ≥ the predetermined value (No in step S10), the HV-ECU 61 calculates the power generation execution power and the regeneration execution power using the calculation formula B and performs charge control. (Step S11), a series of control is terminated.

Further, when the HV-ECU 61 determines that any of the determination conditions of steps S7 to S10 is satisfied (Yes in step S7, Yes in step S8, Yes in step S9, or Yes in step S10). ), Charging control is performed by calculating the power generation execution power and the regeneration execution power using the calculation formula A (step S6), and a series of control is completed.

As described above, in the hybrid vehicle 1 according to the embodiment, when the SOC of the battery 31 is limited to a predetermined value or less and the allowable input power Win of the battery 31 is limited to a predetermined value or less, the power generation by the power generation motor 23 is performed. In a situation where the regeneration by the drive motor 11 is coordinated, the calculation formulas of the power generation execution power and the regeneration execution power are switched between the calculation formula A, the calculation formula B, and the calculation formula C according to each determination condition. As a result, as shown in FIG. 6, the hybrid vehicle 1 according to the embodiment can continue power generation by the power generation motor 23 according to the basic power generation amount map when the accelerator is off even when the brake is on. Since the required regenerative power is determined in consideration of the power generation execution power from the power generation motor 23, the required battery charging power is controlled within a range that does not exceed the allowable input power Win even if a sudden change in the actual regenerative power occurs. Will be possible. Therefore, the hybrid vehicle 1 according to the embodiment can stably supply electric power from the drive motor 11 and the power generation motor 23 to the battery 31 regardless of the driver's deceleration request or vehicle condition, and thus has a low SOC of the battery 31. It is possible to realize an early exit from the state.

1 Hybrid vehicle 11 Drive motor 12 Drive motor ECU
13 Drive side PCU
14 Transaxle 21 Engine 22 Engine ECU
23 Power generation motor 24 Power generation motor ECU
25 Power generation side PCU
31 Battery 32 Battery ECU
33 Battery temperature sensor 34 Power branch 41 AC charging port 42 AC charger 51 DC charging port 61 HV-ECU
71 Wheel axle 72 Drive wheel

Claims (1)

A rotary electric machine that generates a driving force for driving the wheels, a power storage device that stores the electric power supplied to the rotary electric machine, a generator that generates electric power for charging the power storage device, and a driving force for driving the generator. A charge control device mounted on a vehicle equipped with an engine to generate electricity.
When the electric power that can be supplied to the power storage device is not more than a predetermined value, and the power supply to the power storage device by the regeneration of the rotary electric machine and the power supply to the power storage device by the power generation of the generator are performed at the same time. teeth,
When there is a change in a predetermined vehicle condition such that the regenerative demand increases, the electric power supplied to the electric power storage device by the regeneration of the rotary electric machine while giving priority to the electric power supply to the electric power storage device by the power generation of the generator. A charge control device characterized by performing control to adjust the power generation.

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