Research Of Low Voltage Synthetic Test System

Low voltage electrical apparatus especially circuit breakers has undertaken animportant responsibility to guarantee the reliability of power system. The test of breakingshort-circuit current is a necessary method to detect the characteristic of circuit breakers.Synthetic test is a commendable mode which is much cheaper and can well reflect thebreaking capability of breakers. So many research institutes on the planet have been take onit for decades.The paper introduces a kind of synthetic test for low-voltage circuit breakers. Firstly,aiming at the common breaking current specification of low-voltage circuit breakers, designthe synthetic test system. Base on the calculation of circuit, make a simulation of someimportant reference quantities through software. Secondly, establish the control systembased on MCU, so that we can reduce manual operation, improve testing accuracy andsuccess rate.The paper firstly introduces the basic principles of circuit breaker interrupting process,and detect the equivalence between the two method of synthetic and direct test. Meanwhile,according to IEC and GB of circuit breakers, design the circuit of current injection forsynthetic circuit test. Then to the principle of equivalence, compute the parameters ofapparatus in the circuit, and obtain the situation of current and voltage source circuit bytheoretical analysis. Next, using MATLAB/Simulink to simulation the situation of currentsource discharge and TRV. Compare the simulation result with theoretical analysis result,and make sure the designing is correct. After that, build the control system based on MCU.At the end of the paper, discuss some incident and safety problems, then finish thedesigning.In the stage of theoretical analysis, this paper focuses on the discuss of situation ofasymmetric circuit break, according to the IEC and GB, also make computing andsimulation, the result tells it meet the requirements.Above work complete the design of synthetic test system. Considering the actualexperiment condition in design process, which make the experiment has practical value. TheMCU technology also makes control system more accurate and improve success rate.