Three-phase dynamic voltage compensator with reduced switch-count and absence of energy storage system

The utilization of dynamic voltage restorers to protect sensitive loads against short-term voltage disturbances has proved to be a competitive solution in medium and high power applications. For low power applications further cost reductions are required to make the technology even more competitive, although just a few number of studies have already been conducted in this area. This paper discusses the design and operation of a three-phase dynamic voltage compensator, including control strategies for the converters. The proposed topology and control strategies are evaluated through a simulation study with the use of real measurement data, selected by the IEEE Power Quality task force for the characterization of power quality events and device performance evaluation. An experimental implementation of the compensator is developed to allow a better evaluation of specific and critical operation modes, as the forced commutation of the thyristors and the inverter operation.