Abstract

The Electric Spring is a promising new technology that has immense potential to stabilize future power grids that have a large number of renewable energy sources connected to them. Based on Hooke's law for mechanical springs (hence the name ‘Electric Spring’) it is a versatile reactive power controller that not only helps in regulating the grid voltage by controlling real and reactive power flow but also stores electric energy and damps out electric oscillations. The unique aspect of the Electric Spring that differentiates it from ordinary reactive power controllers is that it adopts an “input feedback - input voltage control” as compared to the “output feedback - output voltage control” in traditional RPCs. This subtle change in control strategy helps in making loads connected to the grid adaptive to the availability of intermittent renewable power generation, thus achieving effective demand-side management capabilities. In this paper an improvised control scheme for the Electric Spring based on the synchronous frame control method for single phase full-bridge inverters is presented. With the help of MATLAB simulations it is proved that this method can provide fast dynamic voltage regulation and power quality improvement for the grid.