Performance evaluation of electric spring: Effect of load variation on voltage regulation

Electric spring is a new smart grid technology which can regulate voltage fluctuations caused due to integration of intermittent renewable energy sources. So far electric springs have been studied mostly with resistive loads which are ON all the time. This paper analyses the performance of electric spring when connected with different types of variable loads. The electric spring circuit was simulated in MATLAB/Simulink environment with three types of loads - resistive, resistive-inductive and resistive-capacitive. The circuit was modified such that some of the loads are OFF for a certain part of the simulation. The effect of load variation on the performance of electric spring did not vary with the type of load. However, the change in stress on electric spring with load variation depends on the type of load attached to it. A detailed analysis has been provided in the paper.