Conservation Voltage Reduction in low voltage distribution networks in Ghana

Abstract

Conservation Voltage Reduction (CVR) is the practice of lowering voltages to the lower limit of the acceptable voltage range while keeping it in the voltage range. CVR is considered globally as part of the energy savings program. The journey to save energy in power systems has led to the exploration of Volt/Var optimizers and voltage optimization including CVR implementation. CVR is implemented because of the problems that come with operating close to the upper limit of the acceptable voltage range such as mass of wasted energy as well as higher than necessary electrical bills and reduced lifespan of equipment. The problems that come from operating at a voltage level close to the upper limit affects both consumers and distributors. This capstone project showed that implementing conservation voltage reduction in an 11kV/400V distribution network will provide some level of energy savings to both the consumer and utility distributor. In this project, PSCAD is used for designing the schematic for both the control and CVR models of the 11kV/400V distribution network. The control schematic being the original distribution network layout available and the CVR schematic being the distribution network layout with the CVR implementation using load tap changers and capacitor banks. MATLAB/Simulink was used to model both the control and CVR models with real time parameters either calculated or referenced from the Electricity Company of Ghana. The simulation results for the CVR model managed to maintain the voltage within the range of 220-230V under conditions such as overvoltage and undervoltage. Keywords: Conservation Voltage Reduction, Capacitor Banks, OLTC transformer