Electromagnetic Radiation Distribution in a High Voltage Test Environment

The transient electric and magnetic fields radiated by the discharge of a high voltage impulse generator have well-known effects of creating serious interferences with the measuring and recording equipment. These effects may result in the mis-operation, or in the worst case, may damage the electronic circuitry of the measuring system. Measurements were performed to investigate the characteristics and distribution of electric and magnetic field components originating from the operation of a 3MV impulse generator. E-Field and H-Field were simultaneously recorded and measured independently. D-dot probes measuring the time rate of change of electrical displacement and loop probes observing the time rate of change of magnetic fields were used. The electromagnetic interferences in the vicinity of the impulse generator and control room and the dependence of these interferences on the charging voltage of the generator, elevation, and type of connection arrangements are investigated. The results and discussions from this study can be used for the cost-effective electromagnetic shielding of sensitive measurement equipment in large high voltage laboratories.