Dynamic Optimization of SVR Control Parameters for Improving Tap Operation Efficiency of Voltage Control in Distribution Networks

In this study, we propose a new optimization method to determine the control parameters of a step voltage regulator (SVR) to maximize its voltage control characteristic in distribution networks (DNs) with photovoltaic systems. Considering the service life of an SVR, the proposed method evaluates the expected number of tap operations and the voltage control performance based on the past voltage measurements obtained with sensors in the DN. Subsequently, the time series of two control parameters, that is, the reference voltage and the dead bandwidth, are determined for the most improved voltage control characteristic of the SVR, maintaining the number of tap operations within the upper limit. Voltage control simulation using a realistic 6.6-kV DN model is conducted to show that the proposed method significantly reduces the voltage violation compared with the conventional SVR control using fixed parameters, as well as the alternative SVR operation developed in our previous study, in which the reference voltage was temporally updated. In addition, the simulation results demonstrate that the proposed method realizes efficient tap operations to mitigate the voltage violation, whereas the conventional method requires a much larger number of tap operations to mitigate the voltage violation to the same degree.