Evaluation of load graph indicators transformer substations in the development of the network electric vehicle charging stations

The article considers the problem of assessing the impact of charging stations on the load schedules of transformer substations. The solution of the problem is based on the example of facilities undergoing trial operation in the automotive sector of railway transport. The parameters of the electric vehicle charging station and battery are used for a slow charging option based on an AC charging station and a battery with a rated voltage of 346 V and an energy consumption of 48 kWh. To assess the impact of the charging station operation, the results of the trial operation of an electric vehicle are considered. The assessment was performed for a number of load graph indicators. To consider and evaluate the dynamic processes observed during the operation of the charging station, a simulation model has been developed containing a controlled rectifier converter and a charge current limiter implemented using pulse width regulation. The charging station model has voltage and current level control, which are determined based on factory specifications. The results obtained can be used to evaluate the performance of transformer substation schedules when expanding the charging infrastructure, evaluate electricity quality indicators for various circuit solutions used to regulate charge voltage and current, develop demand management measures in electric vehicle charging processes, and develop recommendations for ensuring electricity quality indicators. The results of the work are an assessment of the effect of the charging station operation on the load schedule of the transformer substation, a simulation model of the charging station for testing control algorithms, battery charging protocols and circuit solutions for current rectification and inversion processes.