Fuzzy-based control of on-load tap changers under high penetration of distributed generators

Voltage regulation in the distribution networks becomes more challenging when the distribution generation (DG) units are introduced. The reasons behind that are: the reverse power flow which is introduced by the DG units, in addition to the probabilistic nature of the generated power due to renewable-based DG units. In this paper, a fuzzy algorithm is proposed to provide an adaptive reference of the OLTC controller, such that the OLTC, which feeds a multiple feeders, can mitigate the effect of the high penetration of the DG units. The motivations behind using the fuzzy logic are: 1) it can map nonlinear relations behind its inputs and output; and 2) it can provide a smooth transition, which lead to a more relaxed tap operation compared to the conventional logic control. The proposed fuzzy algorithm is tested using a radial structure distribution network which is modeled using SIMULINK/MATLAB.