Hybrid power vehicle shifting control optimization method in braking process

Abstract

The invention relates to a hybrid power vehicle shifting control optimization method in a braking process; the optimization method comprises an upshift control method and a downshift control method; the downshift control method comprises the following steps: building a vehicle dynamics model, and building downshift rule target functions, wherein the downshift rules comprise an economical downshift rule, a safety type downshift rule and a dynamical type downshift rule; DOE sampling, and optimizing each sampling point so as to obtain an optimal downshift speed vs and a target function value corresponding to the optimal downshift speed; comparing the target function value corresponding to the optimal downshift speed with the target function value corresponding to a non-downshift status, thus obtaining a shifting condition factor R, and determining whether to shift or not according to the shifting condition factor R; forming a shifting rule determined by a vehicle acceleration as, a motor torque Tm and the optimal downshift speed vs. The novel method allows the hybrid power vehicle to have more reasonable shifting strategies in the braking process, thus improving vehicle fuel oil efficiency, and reducing gas emission.

Description

technical field [0001] The invention relates to the technical field of hybrid electric vehicles, in particular to a method for optimizing shift control of a hybrid electric vehicle during braking. Background technique [0002] As the country gradually increases the control of fuel emissions, hybrid vehicles will have great development potential in the future due to their good fuel economy and emissions. Due to the common output capability of the motor and the engine, the motor is used as the power source to achieve higher fuel efficiency when the fuel efficiency of the engine is not high. When the vehicle brakes, a large amount of kinetic energy of ordinary vehicles will be consumed in the form of heat energy. Hybrid vehicles can also convert part of the braking energy into electric energy recovery to achieve the purpose of energy saving. In this paper, the energy recovery in the braking process is taken as the starting point, and the shift parameters in the braking proces...

AI Technical Summary

Problems solved by technology

Most of the above shifting strategies are considered relatively single, only considering the performance of a certain aspect of the vehicle, such as the amount of regenerative braking energy recovery, so it can only reflect the superiority of the vehicle in a certain aspect, or does not consider the vehicle's performance during the braking process. or did not consider the difference in shifting strategies under different driving demands, or did not consider the impact of the shifting process on the formulation of shifting strategies, or did not compare the vehicle performance without shifting

Images