Strategy to Prevent Overload of Transformer in Distribution System with High Penetration of Electric Vehicle

Though technological advancements bring convenience to humans, they also pose environmental damage. EVs are an alternative that tackles these concerns. However, the growing popularity of EVs is starting to cause problems in distribution systems, especially when the uncoordinated charging of EVs in each house risks overloading distribution transformers. This paper proposes efficient strategies for managing EV chargers in houses. In the event of transformer overload, the proposed control system will control the EV chargers of each house to decrease the power output. However, consumers have an option to pay an additional fee to retain the privilege of charging their EVs without any reduction in power output. Consumers who do not pay an additional fee will experience a proportional reduction in power output. This strategy provides an option for consumers who require charging urgently. To test the effectiveness of the proposed method, this paper utilized two test systems. The first test system is a seven-bus system featuring a 100-kVA distribution transformer, and the second test system is an IEEE European LV feeder featuring a 500-kVA distribution transformer. Test results indicate that the proposed strategy can prevent overload of distribution transformers. This approach helps alleviate concerns about the increasing demand for EV charging in numerous houses during peak usage times.