University research approach to switchgear technology//// circuit switching phenomena

The calculation of transient recovery voltage (TRV) was investigated. The current injection principle was used to simplify the calculation. The source side impedance and ramped injection current gives the TRV. The TRV is expressed by the 4 parameter in the standard. The standard TRV is modified by switching circuit conditions. The synthetic short-circuit testing needs to know the TRV modification beforehand. The Laplace transformation is applied to express the 4 parameter TRV by segmenting the straight line. It was shown that the TRV modification by an arrester can be calculated easily by the proposed method.