The Design Of High-Performance DC Motor Drive

DC motor with output torque,high control accuracy,good dynamic performance is widely used in mechanical processing,medical equipment,home appliances and automobiles,etc.In view of the large size and single fuction of domestic drives,expensive price of foreign drives,propose high performance DC motor driver technology requirements,the speed control and protection functions are analyzed and studied,This paper analyzes the existing problems and causes of the current DC driver,and studies the development and research status of the DC driver at home and abroad,puts forward the optimization design method,and builds a set of DC motor driver experiment system,through the experiment to verify the feasibility of the optimization design method.The main work of this paper is as follows:(1)Analyze the principle and advantages of PID control,and a fuzzy PI controller is designed on the basis of fuzzy control.According to the structure and mathematical model of the brushless DC motor,a simulation model is constructed in the MATLAB/Simulink environment.The effect of fuzzy PI on the suppression of speed fluctuations is verified,and the stability and adaptability of motor operation are improved.(2)The type,reason and location of the failure of the DC motor drivers are analyzed,and the solutions to the over-voltage fault and short-circuit fault are proposed.A protective circuit based on auxiliary triode and capacitor is proposed to solve the crosstalk problem of bridge arm caused by overvoltage of gate source.;In order to solve the problem of terminal voltage oscillation of drain-source,the methods of laminated DC bus capacitance and parallel bus capacitance and the selection of appropriate gate drive resistance are proposed;The shortcircuit protection circuit based on desaturation detection is designed for short-circuit fault(3)According to the function and requirements of the motor driver,the hardware part and software part of the motor driver are designed.The hardware includes DC motor drive main circuit,working parameter detection and protection circuit,power management circuit,microcontroller and communication circuit.The software part includes the main program,intelligent speed control software,driver self-protection control software,fault self-diagnosis software and human-computer interaction software.Finally,based on the designed hardware and software,a set of DC motor driver experimental system is built.The experimental results show that the hardware and software design of the driver is reasonable,and the adjusting time,speed control precision and protection function of the driver meet the design requirements,which verifies the effectiveness of the research technology.