一种基于功率开关的大功率恒流源

Abstract

针对交流恒流的使用要求,设计了一种基于ATMEgA16单片机的大功率交流恒流源控制系统。采用一种改进的SPWM计算方法,由ATMEgA16单片机产生SPWM方波,精确、快速控制H桥逆变电路。同时采用闭环控制,电流传感器时刻监测输出电流反馈到单片机,在一个载波周期内由单片机做出调整,达到输出电流恒流。实验证明,系统具有输出电流可调节范围大、动态响应好、生产效率高等特点。

For the application requirements of AC current sources, a control system for high-power AC current source based on ATMEGA16 is introduced in this paper.An improved SPWM calculation method is prestented.The system uses a microcontroller to generate precise SPWM rectangular waves and controls the H-bridge inverter circuit accurately and quickly.Meanwhile, with the closed-loop control completed by the current sensor monitoring the current outputs and providing feedback, the microcontroller can make adjustment in a carrier period to keep the current outputs invariable.The tests show that the system has a wide adjustable output range, good dynamic response, high production effi ciency, and so on.