Improved voltage disturbance generator for the performance test of the custom power devices

An improved voltage disturbance generator is proposed. To test the performance of the custom power devices such as DVR, SSTS, dynamic UPS, etc., a voltage disturbance generator is necessary. The proposed generator has good features of high reliability, low cost, simple structure, high efficiency, and reduced voltage drop. The main switching device is SCR thyristor, and all the thyristors have natural commutation characteristics, which provides reliable system. The circuit analysis and operating principle of the proposed scheme are described in each mode of voltage sag, swell, outage, and unbalance. Simulation and experimental results show the usefulness of the proposed scheme.