Power Electronics Based Programmable High Voltage Test Source
Conventional high voltage test sources, i.e., transformers (cascaded and resonant), impulse generators, and rectifier circuits generate 50 Hz/60 Hz sinusoidal, lightning and switching impulses, and DC respectively. For arbitrary wave shapes, function generator and HV amplifier setup are available up to 60 kV and few kHz signal bandwidths. Superimposed signals (impulses or transients on a sinusoidal or DC) are generated from a careful design of superposition of two voltage sources. The demand of these unconventional test sources is increasing as new electric stresses are introduced in the current electrical power network due to the rise of power electronics. This motivates the search for a novel high voltage test source which can generate arbitrary wave shapes with larger signal bandwidth at higher voltage level. With significant growth of power semiconductor device industry with many multilevel converter topologies, this research project is initiated to build a prototype of a multilevel converter based high voltage test source which can be programmed to generate arbitrary wave shapes. The prototype is developed for KEMA laboratories, targeting their existing business of 36 kV class HV equipment as well as future demands which are difficult/impossible to be generated using existing test sources in the same voltage class.