Design of impulse current generator for surge protection device testing

Abstract

The behavior and performance of surge protection device under the application of lightning impulse are different from that of single stroke test. Since the surge protection device is the most commonly use as a protection device for most of the electrical appliances lightning protection system, a precise method of testing has to be adopted based on natural characteristics of lightning to accurately determine its performance and capability. A surge protection device has to be a non-conductor for operating power frequency voltages. It should behave as a short circuit for transient overvoltage of impulse character, discharge the heavy current, and recover its insulation without allowing the follow up of the power frequency current. High current impulse generator is standard equipment in high voltage laboratories where it is normally used for high current test on power apparatus and equipment. In this work, an impulse current generator is design with a voltage capability of 20kV and a current capability of 5kA to conduct impulse current testing based on natural lightning parameters. When designing suitable impulse current generator, it is customary to apply the respective IEC recommendations. Measuring procedure was simulated via Pspice and Psim software. Satisfactory agreement is obtained between calculation and simulation, confirming the circuit model and parameters adjustment procedure proposed. Moreover, it confirms that simulation is useful to improve the laboratory test capacity.