KR101114383B1 - Method for controlling of hybrid electric vehicle - Google Patents

Abstract

The present invention further includes an economical driving mode "E" shift stage map in a hybrid vehicle to provide fuel economy maximization in various driving conditions.

The present invention is a process for determining whether the economic operation mode is selected when the engine is on, the process of determining the operating condition by analyzing the APS signal if the economic operation mode is selected, and the deceleration torque set for the economic operation mode if the operating condition is a braking condition. The process of controlling the drive of the motor by determining the regenerative braking torque by applying the map.If the driving condition is the acceleration condition, the motor torque and the engine output torque are applied by applying the motor torque map, engine output map and gear ratio map set for the economic operation mode. Determining and controlling the acceleration target gear ratio; and if the driving condition is the constant speed condition, applying the constant speed map set for the economic operation mode to control the engine output.

Hybrid vehicle, economic operation mode, "E" shift stage, regenerative braking torque, acceleration condition

Description

Hybrid vehicle control method {METHOD FOR CONTROLLING OF HYBRID ELECTRIC VEHICLE}

The present invention relates to a hybrid vehicle (Hybrid Electric Vehicle), and more particularly, to the hybrid vehicle that provides an economical driving of fuel economy maximized in various driving conditions further comprising an "E" shift stage map of the economic driving mode. It relates to a control method.

The hybrid vehicle is equipped with an engine and a motor, and according to driving conditions, the engine and the motor are distributed to provide approximately 30 to 40% fuel economy savings than the acceleration of the engine alone.

In addition, ISG (Idle Stop and Go) function is applied to stop the engine and stop the engine while the engine maintains idling, and to start the engine when the restart request is detected, thereby improving fuel economy and emission stabilization. To provide.

In addition, the regenerative braking recovers the deceleration energy to charge the battery, and a high efficiency low voltage DC-DC converter (LDC) that replaces the alternator is applied.

Hybrid vehicles are usually equipped with automatic transmission or continuously variable transmission, and the shift stage selected by the shift lever is P / R / N / D / L or P / R / N / D / 3/2/1. In the "D" shift stage, the 3/2/1 stage is supported according to the shift pattern set by applying conditions such as driving performance, acceleration, power performance, target fuel efficiency, and exhaust of the vehicle.

In a conventional hybrid vehicle, a map is set to provide driving performance during acceleration (acceleration ability to reach 100 KPH, overtaking acceleration, and shifting feeling), and the map during acceleration reflects the driver's intention as quickly as possible to exhibit target performance. To be possible.

However, as it is set to meet only the acceleration operation, there is a disadvantage in that it causes excessive fuel economy loss, causing fuel economy deterioration.

In addition, the map is set mainly for deceleration linearity for deceleration operation.In the case of hybrid vehicles, unlike the general vehicle, the regenerative braking is additionally generated during deceleration. Limited.

In addition, since the map is set to treat the cooling performance more importantly than the fuel economy with respect to the operation of the air conditioning system, a disadvantage arises that the fuel economy is deteriorated.

The present invention has been invented to solve the above problems, the object of which is to further include the "E" shift stage map of the economic driving mode in the hybrid vehicle, and the braking condition and the "E" shift stage is selected by the driver It is to ensure that economic operation of fuel economy improvement is provided according to acceleration conditions and constant speed conditions.

According to another aspect of the present invention, there is provided a control method of a hybrid vehicle, including: determining whether an economic driving mode is selected in an engine startup state; Determining an operating condition by analyzing the APS signal when the economic operation mode is selected; Controlling the driving of the motor by determining the regenerative braking torque by applying a deceleration torque map set for the economic operation mode if the driving condition is a braking condition; Controlling the acceleration target gear ratio by determining a motor torque and an engine output torque by applying a motor torque map, an engine output map, and a gear ratio map set for the economic operation mode if the driving condition is an acceleration condition; If the driving condition is a constant speed condition, the step of controlling the engine output by applying a constant speed map set for the economical operation mode.

According to the above configuration, the present invention further includes an E shift stage map without additional installation of a separate sensor or device in a hybrid vehicle, thereby improving fuel efficiency in various driving conditions, thereby providing fuel efficiency improvement.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

The present invention can be embodied in various different forms, and thus the present invention is not limited to the embodiments described herein.

1 is a view schematically showing a control device of a hybrid vehicle according to an embodiment of the present invention.

The configuration of the present invention is the operation request detection unit 10 and the ECU (Engine Control Unit: 20), the battery 40, BMS (Battery Management System: 50), HCU (Hybrid Control Unit: 60), MCU (Motor Control Unit: 70), a motor 80, an engine 90, a transmission 100, and a driving wheel 110.

The driving request detection unit 10 detects a driver's driving request. The shift stage information selected from an acceleration position sensor (APS) signal, a brake pedal signal, and a shift lever for a start and acceleration request (P / R / N / D / E / L) is detected and information about it is output.

The ECU 20 controls the overall operation of the engine 90 according to the driving request signal from the driving request detection unit 10 and engine state information such as cooling water temperature and engine torque.

The ECU 20 has a map of the engine output torque according to the APS as shown in FIG. 3, and a general operation mode as shown in FIG. Compared to the engine output torque according to the APS applied in the "D" shift stage, as shown in (b), the range of the map value is wider (W), so that the map with reduced torque change rate for the APS is applied.

Therefore, even when a sudden input of the APS is detected, the actual engine output torque is greatly reduced, and thus the acceleration responsiveness may be somewhat delayed, but the fuel economy is improved.

The shift stage "E" is to be selected through a shift lever or selected by turning on a button designated at the shift stage "D", and the configuration thereof may be variously changed according to design.

In addition, as shown in FIG. 4, the target engine RPM for the APS is set as a map in the ECU 20 to adjust a change rate of the target RPM according to a driver's request value.

In the target engine RPM map, the "E" shift stage sets the target engine RPM more filtering than the "D" shift stage, thereby reducing the rate of increase of the RPM, thereby ultimately reducing the gear ratio change rate.

That is, the relationship between the engine RPM and the vehicle speed in the "D" shift stage, which is the general driving mode, and the "E" shift stage, which is the economic driving mode, is maintained for the signal of the same APS as 5.

The battery 40 supplies the voltage to the motor 80 in the hybrid mode, and recovers the regenerative braking energy at the time of deceleration and is charged.

The BMS 50 manages and controls the SOC state of the battery 40 by comprehensively detecting information such as voltage, current, and temperature of the battery 40, and controls the amount of current supplied according to the output torque of the motor 80. .

The HCU 60 is an upper controller that controls the overall operation of the hybrid vehicle. The HCU 60 connects controllers to networks for each device to exchange information with each other, and executes cooperative control to output torques of the engine 90 and the motor 80. Control and maintain the driving by controlling the target gear ratio.

The HCU 60 determines a target gear shift stage by applying a shift pattern map set according to current vehicle speed, gear ratio, engine RPM, transmission oil temperature, and the like, and controls the gear ratio of the transmission 100 accordingly. Adjust torque and vehicle speed (RPM).

In the HCU 60, a map for regenerative braking amount at deceleration is set as shown in FIG. 6, and at the "E" shift stage, which is an economic operation mode, the regenerative braking amount is kept high even at the expense of some deceleration. It ensures a stable charging amount of, thereby improving fuel economy in acceleration and constant speed operation.

The MCU 70 controls the output torque of the motor 80 according to the driving conditions under the control of the HCU 60 to share the output torque of the engine 90 in the current driving conditions.

The motor 80 is driven by the voltage of the battery 40 and supports the output torque of the engine 90.

Engine 80 is controlled output torque and rotation speed under the control of the ECU 20, the ISG function is executed to provide fuel economy improvement.

The transmission 100 adjusts the transmission ratio according to the control of the TCU 30 by transmitting the output torque transmitted by the combination of the engine 90 and the motor 80 to the driving wheel 110 through the differential gear to drive the vehicle. To help.

Since the general driving mode in which the "D" shift stage is selected in the hybrid vehicle according to the present invention including the above-described functions is made the same as or similar to the normal operation, the description of the operation thereof is omitted and according to the present invention. Only the control operation in the case where the economical operation mode "E" shift stage is selected will be described.

In the state in which the hybrid vehicle according to the present invention maintains the start-up, the HCU 60 includes an operation pedal and whether the accelerator pedal is operated and a displacement, the brake pedal is operated, and a shift stage selected by the shift lever through the driving request detection unit 10. The operation information is detected, and information provided by the controller for each device connected to the network is detected (S101).

In operation S102, it is determined whether the "E" shift stage, which is the economic operation mode, is selected from the information provided by the driving request detection unit 10.

If the "E" shift stage is not selected in S102, the process returns to step S101. If the "E" shift stage is selected, the APS signal is analyzed to determine whether the accelerator pedal is turned on (S103).

If the APS signal is in the off state, that is, the accelerator pedal is in the off state in step S103, it is determined as a deceleration condition, and it is determined whether the operation of the brake pedal is on (S201).

If the brake pedal is in the OFF state in S201, the regenerative braking amount is determined by determining the driving condition of the elastic driving (S202).

The determined regenerative braking amount is determined in a direction in which the regenerative energy is increased as compared with the regenerative braking amount of the shift stage “D” in the normal operation mode.

Subsequently, regenerative braking torque filtering of the "E" shift stage is performed according to the conditions such as the gear ratio, vehicle speed, engine RPM, deceleration, cooling water temperature, transmission oil temperature (S204), and the amount of regenerative braking torque at the "E" shift stage. Determine (S205), and control the torque of the motor 80 through the MCU 70 to execute the regenerative braking control according to the elastic running deceleration (S206).

If the brake pedal is in the ON state in the determination of S201, the brake regenerative braking amount is determined by determining the deceleration condition according to the brake operation (S203).

The brake regenerative braking amount is determined in a direction in which the regenerative energy is increased in comparison with the regenerative braking amount determined in the "D" shift stage, which is a general operation mode.

Subsequently, the regenerative braking torque of the "E" shift stage according to the brake operation is filtered according to the conditions such as the gear ratio and the vehicle speed, the engine RPM, the deceleration rate, the coolant temperature, the transmission oil temperature (S204), and the regeneration at the "E" shift stage. Finally, the braking torque amount is determined (S205), and the torque of the motor 80 is controlled through the MCU 70 to perform deceleration regenerative braking control according to the brake operation (S206).

In the determination of S103, if the APS signal is on, that is, the accelerator pedal is on, it is determined as an acceleration or constant speed condition, and the engine output map of the "E" shift stage, the target gear ratio map of the "E" shift stage, and the "E" shift are determined. The target motor torque map of the stage is applied (S311) (S312) (S321).

The engine output torque is determined from the engine output map (S314), the target gear ratio is determined from the target gear ratio map, and then filtering is performed according to conditions such as the current gear ratio, vehicle speed, engine RPM, deceleration, cooling water temperature, and transmission oil temperature. To determine the optimum gear ratio (S313).

The target gear ratio of the shift stage "E" is applied according to whether the air conditioner system is operating (S331) (S332).

Then, the motor torque is extracted from the "E" shift stage target motor torque map applied in S321 (S321), and then filtered (S322) to determine the acceleration motor torque (S323).

Compensation is applied to the motor torque extracted from the target motor torque map according to whether the air conditioning system is operated (S341) (S342).

It is determined whether the input torque of the transmission 100 determined by the sum of the acceleration motor torque determined in S323 and the engine output torque determined in S314 is smaller than the minimum RPM limit torque (S315).

If the input torque of the transmission 100 is not smaller than the minimum RPM limit torque in the determination of S315, the acceleration target gear ratio of the "E" shift stage is controlled (S316), and the input torque of the transmission 100 is the minimum RPM limit torque. If it is a smaller state is determined as the constant speed driving condition and the constant speed minimum RPM down maintenance control is executed (S340).

The constant speed running at the "E" shift stage lowers the engine RPM by approximately 100 RPM (A ') than the "D" shift stage (A), which is a normal operation mode, as shown in FIG. To be provided.

The minimum RPM limit torque is determined according to the characteristics of the transmission 100.

In the above description, the engine output map, the target gear ratio map of the "E" shift stage, and the "E" shift stage target motor torque map are adjusted somewhat insensitively than the values set in the "D" shift stage in the normal operation mode.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It is included in the scope of rights.

1 is a view schematically showing a control device of a hybrid vehicle according to an embodiment of the present invention.

2 is a flowchart schematically illustrating a control procedure of a hybrid vehicle according to an exemplary embodiment of the present invention.

3 is a diagram illustrating an engine output torque map according to an APS set in a hybrid vehicle according to an exemplary embodiment of the present invention.

4 is a diagram illustrating an engine RPM map according to APS set in a hybrid vehicle according to an exemplary embodiment of the present invention.

5 is a diagram illustrating an engine RPM and a vehicle speed map according to APS in a hybrid vehicle according to an exemplary embodiment of the present invention.

6 is a diagram illustrating a regenerative braking amount map at deceleration in a hybrid vehicle according to an exemplary embodiment of the present invention.

7 is a diagram illustrating a relationship between engine RPM and torque in a hybrid vehicle according to an exemplary embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

10: operation request detection unit 20: ECU

40: battery 60: HCU

70: MCU 80: motor

Claims (8)

delete delete Determining whether the economic operation mode is selected while the engine is on; Determining an operating condition according to the APS signal when the economic operation mode is selected; Controlling the driving of the motor by determining the regenerative braking torque by applying a deceleration torque map set for the economic operation mode if the driving condition is a braking condition; Controlling the acceleration target gear ratio by determining a motor torque and an engine output torque by applying a motor torque map, an engine output map, and a gear ratio map set for the economic operation mode if the driving condition is an acceleration condition; In the control method of the hybrid vehicle comprising the step of controlling the engine output by applying a constant speed map set for the economic driving mode if the driving condition is a constant speed condition, The regenerative braking torque is a control method of a hybrid vehicle, characterized in that divided into the regenerative braking amount of the resilient driving deceleration condition and the regenerative braking amount of the brake deceleration condition according to the brake off. The method of claim 3, The regenerative braking amount of the resilient driving deceleration condition and the regenerative braking amount of the brake deceleration condition are determined by applying torque filtering to gear ratio, vehicle speed, engine RPM, deceleration, cooling water temperature, and transmission oil temperature. Control method. The method of claim 3, The regenerative braking amount of the brake deceleration condition is controlled in the amount of regenerative energy than the normal driving mode. The method of claim 3, The control method of the hybrid vehicle, characterized in that the compensation is applied according to whether or not the operation of the air conditioning system in the acceleration condition. The method of claim 3, If the transmission input torque determined by the sum of the motor torque and the engine torque in the acceleration condition is less than the set limit torque, it is a constant speed condition, and if the transmission input torque exceeds the set limit torque, it is determined that the acceleration condition. Way. The method of claim 3, The motor torque map, the engine output map, and the gear ratio map set for the economic driving mode are set to be insensitive to the general driving mode.

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