Energy loss evaluation of a battery buffered smart load controller

Abstract

This paper aims to evaluate the energy and power loss of a single-phase battery-buffered smart load (BBSL) under demand-side primary frequency control (PFC). The BBSL consists of a battery and a power & energy management system (PEMS), the evaluation in this work entails the experimental measurement of the energy lost in the battery during the charge and discharge procedures dictated by the PFC and the measurement of the power lost in the PEMS. A method is developed to measure the battery energy loss using the smart load strategy by maintaining the battery state of charge (SOC) constant over the PFC regulation period. The effects of the PFC droop characteristics and dead-bands on battery energy loss are studied. The experimental measurements of the energy loss are confirmed by simulation of a battery model in which the total voltage drop of the battery is represented by a nonlinear current-dependent resistance. Then, the power loss associated with the power electronic converters of the PEMS is experimentally determined under different PFC droop and dead-band settings.