Design Of Control System Of Low-pressure Molded Case Circuit Breaker

The low-voltage molded case circuit breaker is the most widely used protective electrical apparatus,and the controller is the core device of the circuit breaker,in the low voltage distribution system.The research of the low-voltage molded case circuit breaker control system is one of the school-enterprise cooperation projects.After analyzing the functions and development status of the breaker,the two types of functions that switching action of permanent magnetic operating mechanism and parameter measurement of circuit breaker display are studied.According to the preliminary enterprise design of the virtual prototype size and developed technical indicators,the project plan of low-voltage molded case circuit breaker control system is put forward.And the feasibility of switching action controlled IGBT driven circuit is proved.Also the signal acquisition module,dsPIC33FJ64GS606 and dsPIC33FJ06GS101 master-slave processor control module,digital signal detection module,man-machine interface module,drive modules,power modules and other hardware are designed.Meanwhile the relay protection algorithm of three-stage current protection and voltage protection are studied.The hardware of the control system is set up,and the software of the control system is completed.The basic functions including voltage,current,apparent power,active power,reactive power and power factor parameters measurement,liquid crystal real-time display and other basic functions are realized.Three-stage current protection,voltage protection and switching action of permanent magnetic operating mechanism and other protective functions are verified.