Probabilistic Approach to Investigate the Impact of Distributed Generation on Voltage Deviation in Distribution System

The stochastic nature of integrated renewable-based distributed generation (DG) and changing the conduct of power consumption adds randomness to the bus voltage. Consequently, the distribution system faces voltage limit violations on a few buses. In this scenario, the traditional voltage control methods are unable to handle the fast voltage deviation. The voltage control using the voltage controlling capability of available DGs gives a fast and dynamic solution. In this regard, the information about the impact of power perturbation at the DG-integrated buses on the voltage deviation gives insightful information for maintaining the voltage profile within its permissible limits. Evaluating this information using the traditional probabilistic load flow method is computationally inefficient for real-time applications. Therefore, a principal component analysis (PCA) based novel probabilistic voltage sensitivity index (PVSI) is proposed.It ranks the impact of power perturbation at DG-integrated buses on the voltage deviation at any bus. The PVSI is analytically obtained to reduce the computation time for ranking. Due to the advantage in computation time, the proposed method enables the distribution system operator (DSO) to use this information for fast and dynamic voltage control in a real-time scenario. Further, the proposed PVSI is validated on the 69-bus and the 141-bus distribution systems by comparing it with the traditional Monte-Carlo simulation (MCS) and Joint Differential Entropy (JDE) methods.