Design and implementation of electric spring for constant power applications

Electric spring has recently been proposed as a special type of reactive power compensator to improve various attributes of the smart grid. Its extended functionality and applications are yet to be explored. This paper presents a new application of electric spring to ensure constant power across the loading elements under impedance variations. Two control methodologies are proposed to carry out this task: a linear approximation configuration and a closed-loop configuration. Design and mathematical analysis are provided, and the results of both control configurations are analyzed for a simulation model as well as a hardware setup. It has been found that experimental results are congruent with those obtained from the simulation model, hence ensuring the efficacy of theoretical framework.