446 / 2017-05-01 19:32:09

Load allocation of test station for short-circuit experiment based on FEM analysis of distributed conductance

Photovoltaic system,DC circuit breaker,Short-circuit test,FEM analysis,Load allocation

Due to the rapid development of photovoltaic system, experimental requirements of DC circuit breakers for photovoltaic system also increase quickly. According to UL489B and IEC60947-2 appendix P, time constant of short circuit is normally smaller than 3ms and the amplitude of short circuit is very high.
Low voltage test station usually has several dozen of types of electric resistance and inductance. By switching combination of different load units, the required experimental parameters can be achieved. Though in the conditions of small time constant and high short circuit, the distributed inductance of test loop can greatly affect prospective short-circuit current. Then it’s difficult to calculate distributed inductance. Because numbers of possible switching combination is enormous, the experiments for achieving load allocation plan will waste large test cost and power energy. In this study influence of the arrangements of load units into the distributed inductance is calculated by using CAE software. Distributed inductances with Different locations, shapes and connection bus are listed in calculated table. By considering nominal parameters of load units and looking up above table, the load allocating plan can be easily achieved without experiments.