| The brushless DC motor not only has high operating efficiency and good speed regulation performance,but also has the advantages of simple structure,convenient maintenance and reliable operation of the AC motor.It is an ideal power source for the electric vehicle drive system.The driving motor installed on the electric vehicle is located in a complex environment,the working conditions are changeable,and the start and stop are frequent.However,the current motor controller has slow response speed,low control precision,large stability error and weak anti-interference ability.Therefore,this paper hopes to improve the controller performance by introducing advanced control strategies.The main work of this paper are as follows:Firstly,the overall structure of the control system is determined,and the mathematical model of the brushless DC motor is analyzed.The control system structure is determined by the three parts of the motor body,the position sensor and the power driver.By analyzing the voltage balance equation and motion equation of the motor,the transfer function is deduced,and the mathematical model of the brushless DC motor is established.Secondly,the basic principle and realization method of the vector control algorithm of the brushless DC motor are studied,and the speed regulation control system with double closed loop of current and speed is designed.For the traditional PID controller parameters are fixed,can’t adapt to complex and changeable operating situations.Adaptive adjustment of PID parameters is made using the Simplified Particle Swarm Optimization Algorithm（SPSO）.And the improved PID controller is applied to the speed outer loop of the outer loop of the vector algorithm to improve the control performance of the system.According to the parameters of the control motor,the control system is simulated and modeled,and the simulation results are analyzed.Thirdly,the hardware system and software of brushless motor controller with TMS320F28335 as the core are designed.Including power supply circuit,drive isolation circuit,full-bridge inverter circuit and signal acquisition feedback circuit.Considering the complexity of the operating system and the poor real-time performance,this topic uses the interrupt of DSP to realize multi-task management,and completes the realization of the improved particle swarm algorithm.Finally,a practical test of the brushless motor controller.The experimental results show that,compared with the traditional PID control,under the same adjustment frequency.The controller designed in this subject has the advantages of small adjustment time,wide speed adjustment range and small rotation speed fluctuation,which verifies the feasibility of the design.However,after the introduction of the simplified particle swarm algorithm,due to the large amount of calculation,the DSP operation efficiency is low,and a high setting frequency cannot be achieved.The software and hardware need to be further optimized and improved. |
