Damping torque analysis of energy storage system control in a multi-machine power system

This paper presents the damping torque analysis of an energy storage system (ESS) control in a multi-machine power system. The objective of the analysis is to examine the effect of the ESS control on the power system small-signal stability. Firstly in the paper, a systematic procedure to establish a linearized model of the multi-machine power system with the ESS installed is presented. Secondly the damping torque contribution from the ESS control, including the normal voltage control functions and the supplementary damping control function, is derived. Finally an example multi-machine power system installed with a battery energy storage system (BESS) is given in the paper. Results of damping torque analysis are confirmed by the computation of system oscillation mode and non-linear simulation.