Control method utilizing motor to start engine for double-clutch type hybrid electric vehicle

Abstract

The invention enables a novel single-motor and double-clutch type hybrid electric vehicle to be a study object and provides a control method of the process of utilizing a motor to start an engine during vehicle running. First a structure and a working mode of the hybrid electric vehicle are analyzed, a system dynamics model is established, a working range of the hybrid electric vehicle is divided, corresponding torque management strategies are formulated; then in the practical application process, whether the conditions for utilizing the motor to start the engine are achieved is judged by calculating demand torque, value of state of charge (SOC) of a battery, a rotating speed of the motor; and when the conditions for utilizing the motor to start the engine are achieved, model switch is performed, a moment-limiting clutch jointing instruction is sent out, and the processing of utilizing the motor to start the engine is achieved by controlling oil pressure of a moment-limiting clutch hydraulic cylinder and utilizing the formulated torque coordination-control strategies to perform coordination control of motor torque, engine torque and transmission torque of a moment-limiting clutch. By utilizing the advantage that the motor responds fast and timely increasing or reducing the motor torque according to the control strategies, the control method provides the demand torque for starting the engine during the vehicle running or compensates the insufficiency of the engine torque, reduces impact degree in the switching process and improves ride comfort of the hybrid electric vehicle.

Description

technical field [0001] The invention relates to the technical field of automobile manufacturing, in particular to a single-motor double-clutch hybrid electric vehicle as a research object, and a control method for starting an engine through a motor when the vehicle is running is proposed. Background technique [0002] Since the 1990s, major automobile companies in Japan, the United States, and Europe have devoted themselves to the development of hybrid vehicles. After entering the 21st century, various countries have accelerated the process of industrialization of hybrid electric vehicles, and successively launched different forms of hybrid electric vehicle products. However, hybrid vehicles have multiple working modes, and there is a process of switching between working modes. During this process, large torque fluctuations are likely to occur, and torque coordination control is required to reduce the impact and improve the operating mode. The smoothness of the switching pr...

AI Technical Summary

Problems solved by technology

In terms of structure, more double-motor structures are used. Compared with single-motor, its main advantage is stable operation, but the cost is higher.

For the single-motor double-clutch structure strong hybrid electric vehicle in this paper, the structural cost is low, but its dynamic process is complex, and coordinated control is even more important.

If the control is not proper, it will cause the motor to start the engine, prolong the engine starting time, produce a large impact, and deteriorate the ride comfort of the car.

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