Grid Impact Analysis and Mitigation of En-Route Charging Stations for Heavy-Duty Electric Vehicles

TL;DR

This paper analyzes the grid impacts of heavy-duty EV charging stations, proposing placement strategies and mitigation solutions like smart chargers, PV, and energy storage to reduce adverse effects and optimize costs.

Contribution

It introduces a comprehensive impact analysis framework and mitigation strategies for heavy-duty EV charging stations, including optimal placement and sizing methods.

Findings

Charging stations can cause significant grid impacts if not mitigated.

Mitigation strategies effectively reduce grid stress and costs.

Optimal placement and sizing improve system efficiency and cost-effectiveness.

Abstract

This paper presents a consolidated grid impact analysis design and corresponding mitigation strategies for heavy-duty electric vehicle (EV) charging stations. The charging load of heavy-duty charging station can reach several megawatts, which could induce adverse impacts on the distribution grid if not effectively mitigated. To analyze the impacts and provide corresponding solutions, we select four representative distribution systems - including both single-feeder cases and a multi-feeder case - and design thorough test metrics for the impact analysis. The charging load profiles used in the analysis are derived from realistic conventional heavy-duty vehicle travel data. Based on the analysis results, charging stations are placed at three different representative locations in each distribution system: best, good, and worst locations. Mitigation strategies using a combination of smart charger functionality, on-site photovoltaic (PV) generation, and on-site energy storage (ES) are proposed and tested. A sizing method is also proposed to find the optimal PV-ES-charger capacity that minimizes the capital cost.