Calculation of transient electromagnetic fields generated during switching operation in power substation by the method of moment and superposition principle

Switching operations of circuit breakers and disconnector switch radiate transient electromagnetic fields which may interfere and disrupt normal operations of sensitive electronic equipment in power substations. This paper deals with the calculation of transient electromagnetic fields generated due to the switching operation in power substation by the method of Moment (MoM) and superposition principle. Measurement of the transient electromagnetic fields in some points is carried out for two opening and closing small capacitive current test circuits (one using air insulated switchgear and the other using gas insulated switchgear) by fiber-optical measurement system, and the average error between the calculation and measurement result is about 15%-25%. Analysis of the calculation result shows that the transient electromagnetic field at a point mainly depends on the position and the radiated source characteristics. The calculation result could be applied to the EMC analysis of electronic equipment in power substation.