自立型 이동로봇 驅動을 위한 직류서보 전동기 PLL速度制御 시스템에 關한 硏究

Abstract

The speed control problem associated with dc servo motors for direct-drive applications of mobile robot is considered in this paper. The purpose of this paper describes a control circuit and method for dc servo motor in drive of mobile robot. Robot is moved by power wheeled steering of two dc servo motors mounted to it. In order to achieve the high-performance operation of dc servo motor, speed control system is composed of a digital Phase-Locked Loop and H-type drive circuit. And also, drive of motor is controlled Pulse Width Modulations. As the driving circuit in this case has nonlinear characteristics, it is modified to design oh H-type bridge with feedback diodes so that it may show linear characteristics by dealing with magnetic energy stored in motor inductance and also control method is developed. In order to get data on design of control system, 80[W] motor is tested simply by software and analog. In results, optimum period of PWM pulse for a 80[W] motor is 142. And also, speed characteristics of motors is shows linearity and parameters of motor and robot obtained. Digital speed control operation and method are described by phase-locked loop technique. In this case, the PLL control system which is synchronized the speed of motor with the phase of reference signal is schemed. And for the reference signal, the crystal oscillator is used. A linear discrete model is developed and is discussed the design problems and speed variation. The proposed scheme based on the parameters obtained through the experiment shows linearity in speed control characteristics. The complete speed control system applied to 80[W] de servo motors resulted in satisfactory performance. And speed characteristics of motor shows linearity stability and high response.