Design and application of constant current source system

JIN Liangsheng1, ZHENG Yuhai2
(1.College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310023, China;
2.Computer Department, Zhejiang Institute of Mechanical & Electrical Engineering, Hangzhou 310000, China)

Abstract: Aiming at the special requirements of the constant current source for circuit breaker testing, and in order to detect the circuit breaker more accurately, more conveniently and more reliably, a system was designed based on the multimagnetic transformer and PLC control. The magnetic circuit input of the multimagnetic transformer was controlled for getting continuously adjustable voltage. A feedback control was used in the system, and through the current transformer and the PLC, the output current and the target current were compared and made infinitely close, and the control process was divided into zero adjustment, resistance measurement, multiple magnetic circuit input, voltage adjustment and current stability. According to the feedback control system, the control ladder diagram of Mitsubishi PLC and PC software program was designed. By controlling input voltage and resistance, the performance of currency stability was tested for the system. The results indicate that the system is reliable, fast response and high accuracy and the interface of the system is friendly and convenient.
Key words: multimagnetic; transformer; constant current source; PLC