Research On Torque Ripple Control Of Permanent Magnet Brushless DC Motor For Battery Electric Vehicles

Since the worse of global warming and environmental deterioration,as well as the gradual decline in global oil reserves,decarbonizing transport is proving to be one of the major challenges in the 21st century,which in turn stimulates the development of alternative fuels and low-carbon technologies.Nowadays,more and more research institutions and automotive manufacturers have now shifted their effort to develop energy efficiency and renewable energy vehicles.China has also developed a number of policies that are conducive to the development of new energy vehicles in finance,infrastructure and R&D investment,giving strong support to the development of electric vehicles,which gives rise to the formation of the Three Lengths and Breadths development pattern.As one of the key elements in new energy vehicles,electric motor and its control system are crucial to the driving performance and ride comfort of electric vehicles,whose related research is of great significance.Bat algorithm based PID control system of brushless DC motor is analyzed in this paper,supported by Industrial Support Project in Hunan Province(2013GK2005)and Specialization of New Industrialization in Hunan Province(2012GK4009).Following research works have been done:(1)On the basis of the principle and mathematical model of BLDCM,a Matlab/Simulink simulation model of BLDCM is established.speed overshoot and the torque ripple in the simulation results are analyzed,which provides a comparative basis for the next research.(2)A bat algorithm based PID control system for BLDCM is introduced,which combines bat algorithm with ordinary PID controller,and search for the optimal PID parameters using bat algorithm.Taking the same second-order transfer function as the object,the proposed BAPID controller is compared with the PID control based on the genetic algorithm(GAPID).The results show that the response of BAPID controller is faster and stable,and with shorter settling time.The validity of the BAPID controller is verified.Then,the controller is introduced into the brushless DC motor control system.By running Matlab/Simulink simulation,compared with the simulation results under the ordinary PID control system,the speed overshoot and the instantaneous fluctuation of the torque are effectively reduced,and the torque response is more stable during the operation,which confirms the validity of the BAPID controller proposed in this paper.(3)The hardware circuit and software architecture of brushless DC motor control drive system are designed based on the DSP chip TMS320F2812 and the driver chip IR2136,which focuses on the power driving circuit of motor control system,including power-driven switch circuit,zero-crossing detecting circuit,sampling monitoring circuit,power supply and isolation circuit.Based on the designed hardware circuit,the software architecture design of the brushless DC motor control system is carried out.The main program part and the interrupt program part are designed.Finally,the software implementation of BAPID control algorithm is described.