Characteristic example of insulation coordination in power converters

Power electronics devices and modules that are most often used in power supply systems when compared to the passive components usually exhibit a very poor ability to withstand surge voltages. These surge voltages can be of different origins, and in most cases are transient surges. The recorded surge voltages even at low levels can lead to a damage of the mentioned power electronics devices or power converter components. Consequently, it is very important to implement a number of measures to increase the insulation level of the entire system. In this paper the two representative examples of insulation coordination are elaborated: i) an industrial AC drive and ii) photovoltaic inverter used in solar grid-connected power systems.