Improvement of load factor in power distribution networks using electric vehicles

The global population of electric vehicles (EVs) has been steadily growing and is currently experiencing a notable surge. EVs function as a means of transportation and, furthermore, act as both load and distributed generation. An optimal charge/discharge schedule for EVs is presented in this paper to improve the load factor of the distribution system. To increase the participation of EVs in this process, minimizing battery degradation and charging costs is also incorporated as objectives in the objective function. A linear battery degradation model is introduced to calculate the exact degradation of cycle life, considering the initial and final depth of discharge (DoD) of the EVs. A novel load leveling index is proposed to quantify the improvement in load factor. The IBM ILOG C-PLEX optimization studio is used to solve the objective function. The proposed method is demonstrated on an IEEE 33-bus distribution system with EV penetration. The results are presented as two different cases for comparison: before EV scheduling and after EV scheduling. The results depict an increased load factor due to peak shaving and valley filling, energy cost savings for both EV owners and the distribution company, a reduction in active power loss, and an improvement in the voltage profile of the system.