A reliability-constrained demand response-based method to increase the hosting capacity of power systems to electric vehicles

This paper proposes a reliability-constrained demand response-based method to maximise the permissible penetration level of electric vehicles (EVs) at electric power system buses. The continuous increase of EVs will deteriorate the reliability of power systems if no countermeasures are taken. Implementation of demand response (DR) programs can be an effective solution to reduce or even avoid load curtailments. Also, the mobility of EV loads causes a dynamic change in load curtailments. This dynamic change can be captured through building load profiles for EVs considering drivers' behaviour and preferences to charge EVs. The proposed method is developed based on a DR program and load profiles of EVs. In the proposed method, existing load profiles are combined with load profiles for initial numbers of EVs at corresponding buses. The initial numbers are calculated based on total interruptible/curtailable (I/C) loads at system buses and peak load of EVs. Drivers' behaviour and preferences in terms of charging times, periods, and locations are modelled in developing load profiles for EVs. Then, I/C loads-based DR is implemented to restructure load profiles of system buses. Both incentives and penalties are considered to develop the DR program. Finally, the maximum permissible penetration level is calculated by increasing the number of EVs until systems' prior (without EVs) reliability level is achieved. The proposed method is demonstrated on the Roy Billinton Test System, IEEE Reliability Test System, and IEEE-33 Bus Distribution System. Monte Carlo simulation is performed to evaluate the well-known reliability indices of power systems. The results show that the permissible penetration level of EVs in power systems can be increased significantly using the proposed method.