The Design Of Low-voltage And Low Power Servo Drive

Servo-drive technology has been dominated by a pivotal position in the field of control technology industrial. In recent years, due to the continuous efforts of scholars from various countries, servo-driven technologies have achieved new breakthroughs. Among them, high-performance permanent synchronous motor (PMSM) combined with advanced control theory those low-power servo drive is frequently used and growing very rapidly in mechanical arm control, medical equipment, robots and other areas. In view of this, the project designs a low cost but high performance, compact, low-voltage and low power servo drives.Firstly, the paper analyzes the structural characteristics of PMSM, then it constructs the mathematical model based on the motor operating principle. After that, the paper elaborates on SVPWM (Space Vector Pulse Width Modulation) and control theories which are commonly used. Considering the surface mount PMSM's characteristics, the paper selects the id=0 control strategy and SVPWM method. Besides that, the paper discusses its implementation on DSPIC microcontroller. Then it analyzes the control strategy about closed loop control system based on PID, to test the effectiveness of control strategy and parameters, the paper build a simulation model of the fully digital field oriented control of the servo system by using MATLAB'SIMULINK toolbox.The servo system chooses DSPIC33FJ256MC710 as the microcontroller and sets aside CAN, serial and other communication interfaces in the minimum system. The paper shows the current signal acquisition and processing circuit. It also designs the position signal acquisition circuit for incremental photoelectric encoder. For low-power servo drive, the paper gives the proven inverter circuit and protection circuit scheme. Finally the author draws the PCB and builds the hardware platform.The software is developed in Microchip's MPLAB IDE, in order to ensure the performance of the program, the author develops the main program and subprogram module by C language and assembly language. The paper gives the program flow chart. At last the author tests the entire servo system by co-debugging the hardware and software.The author summaries and analyzes the problems encountered in full-text in the conclusion of the paper. The paper point out the deficiencies and areas still need improvement, at last, the author make a looking for the next step.