In order to realize the investigation of protection relaying simulation in power system

we had developed a protection relaying simulation system based on MATLAB. The system consists of system graph constructing module

power flow calculating module

short-circuit calculating module

fault simulation module and protection simulation interface module. Any simulation system module can be constructed by the system

which can deal with transient calculation to process accident prediction

accident replaying and setting investigating. The system has been proven to be an available and efficient method of protection relaying transient measurement. Keyword: checking protection ;transient simulation ;MATLAB