Time-varying stochastic and analytical assesment of CVR in DER integrated distribution feeder

Abstract

Conservation voltage reduction (CVR) is broadly recognized as a smart-grid technique for load and loss minimization by reducing the operational voltage at the distribution substation. Advantages of CVR deployment in distributed energy resource (DER) integrated system are quite substantial due to the power transfer from various locations to the sinks/loads. However, due to the stochastic nature of photovoltaic (PV)/wind based DERs and loads, benefits of CVR might vary from time to time. This paper demonstrates the use of the Analytical Hierarchy Process (AHP) to measure the benefits of CVR at different time instances by estimating the CVR factors, the voltage sensitivity factors, and the loss factor considering load and PV uncertainty. This analysis gives flexibility to the utilities to decide on the timing on CVR arrangements in a specific distribution feeder and good knowledge about CVR benefits for a chosen feeder. Beta and normal distributions are used for solar and load uncertainty modeling, respectively. In addition, the paper provides a probabilistic analysis on the predictive CVR-off operational voltage during the CVR deployment time for approximate estimation of the factors. An existing distribution feeder in Duke Energy's service territory is used to conduct a time-series analysis for analyzing the results.