Distribution of quality power to the consumers is one of the greatest challenges in power industry. In practice, the presence of various nonlinear/sensitive loads disturbs the quality of power supplies in distribution system. Dynamic voltage restorer (DVR) is a custom power device which helps to improve voltage quality in distribution system. In this paper three single phase H-Bridge PWM inverters are used for each phase so as to reduce the voltage rating of the series converters. Synchronous Reference Frame (SRF) theory along with In-phase compensation and Adaptive Fuzzy PI is used as control strategy for DVR. The poor performance by conventional PI controller with fixed gains when the system parameters and operating condition changes is improvised using Adaptive Fuzzy PI controller. The proposed DVR with control strategy is able to improve voltage quality by mitigating voltage sag, voltage swell, phase shift and harmonic problems.
Lekshmi R. Chandran, Ilango Karuppasamy, and Dr. Manjula G. Nair, “Voltage quality enhancement in distribution systems using dynamic voltage restorer with adaptive fuzzy pi controller”, COMPUSOFT: An International Journal of Advanced Computer Technology, vol. 8, 2019.