Electric spring controller design for distribution network loaded by electric vehicles

Although electric vehicles (EVs) offer a viable mean of commuting, their widespread penetration can have adverse effects on the current electrical distribution networks due to voltage drop and overloading of distribution transformers. In this work, a novel control scheme is proposed and implemented to support the voltage profile of a typical distribution network loaded by EVs. Electric spring (ES), a real/reactive power compensator, is driven by the proposed controller to provide voltage support under dynamic loading conditions. In the proposed scheme, the ES reference voltage is continuously determined and then compared with its instantaneous output voltage in a closed-loop configuration. The proposed controller is tested under various loading conditions both through simulations and digital implementation in the hardware-in-the-loop configuration to evaluate its overall performance. Results show that ES equipped with the proposed controller can be successfully used to fix the problem of the voltage drop caused by the sudden and simultaneous charging of EVs.