Experimental studies of influence of load capacitance on the output voltage of the impulse voltage generator

The amplitude, waveform and efficiency are the main factors to evaluate the overall performances of an impulse voltage generator (IVG), especially, under larger load capacitance such as capacitive potential transformer, or with larger test circuit sizes like the testing of EHV equipment. Analysis and experimental studies show that, to the given main capacitance of IVG, the front time would increase to exceed the required range specified by IEC standards under lightning impulses; while the efficiency of the IVG decreases. For switching impulses, the influence of the test circuit parameters, such as series resistance and load capacitance, on the efficiency of the IVG is also investigated. The results show that there exist a set of optimum parameters which not only make the time parameters within the specified limits, but also result in higher efficiency