Assessing the Harmonic and Supraharmonic Impact of Electric Vehicle Charging Facilities

The emergence of large Electric Vehicle (EV) charging facilities in the United States (U.S.) and a lack of knowledge about the Power Quality (PQ) impact of such facilities on the grid has led to fears of increased Electromagnetic Interference (EMI) and harmonic compliance issues. The goal of the research presented in this paper is to demonstrate tools and techniques that can be utilized by utilities to predict this PQ impact. This can help utilities better plan the integration of such facilities and maintain continued grid and load compatibility. In this paper, generic EMTP simulation models of an EV charging facility are first developed and then compared against actual PQ measurements made at EV charging facilities. The simulations show that large EV charging facilities do pose a risk of harmonic incompliance to the power system, and under certain conditions, distortion between 2 and 150 kHz can also pose a risk. Finally, the paper closes with a discussion of the implications of the findings for utilities and the importance of system strength to determine the appropriate feeder for EV charging facility integration.