The Mechanical Properties Testing Device Of Vacuum Circuit Breaker Based On DSP Development

Vacuun Circuit Breaker has been widely applied in medium voltage power system.The availability and reliability of power system is directly determined by the operating performance of VCBs.Power line Conference of the hternational survey shows that the fault in vacuum circuit breaker,the mechanical failure(including the actuator and the control loop) accounts for more than four-fifths of all the failures,other arc blow-out. insulation failure occupy a smaller proportion of,a lower proportion of heat failure. Factory-inspection of manufacture and inspection test of users regard the test of the mechanical character as an important test.Based on the analysis of the results of research and the development trends which with regard to the testing device of circuit breaker at home and abroad. develop a mechanical properties testing device of the vacuum circuit breaker based DSP.In this paper,firstly analyzes the test mechanical natural parameter of the vacuum circuit breaker,and then introduces the hardware and software design of the mechanical character of the vacuum circuit breaker test device,which mainly includes the following sections:(1) The hardware circuit design. First of all,the Hall current sensor that sensitive to instantaneous signal is used to detection the current signal of close(open) coil in theoperating mechanism:the line displacement sensors is adopted to measure displacement signal of the movable contact travel,and converts it into the synchronous voltage signal;the closing/opening control is achieved by relays:It designed peripheral hardware interface circuit with TI's high performance single-chip DSP TMS320LF2407 as the core,including:a sensor input,analog signal conditioning,A/D conversion,switch the input/output,single-chip and PC serial communications etc.(2) The software design.Combination of assembly language with C language to write software program, including the DSP main program,or closing/opening-sampling procedures,A/D interrupt service routine,switching interrupt service routine.Computer Interface program,USB and PC communication program.(3) Communication design.In the process of developing,the mechanical characteristics of vacuum circuit breaker test device use the USB interface,the communication interface is composed of USB controller ISP.1581 and the external circuit,so that the test device substantially increase the speed of data transmission and data storage more convenient.Besides,a method combined hardware and software is used to improve the interference-free ability and reliability of the system.Both dynamic response characteristic and testing accuracy is improved significantly compared with traditional system by testing.