Power Hardware-in-the-Loop Demonstrator for Electric Vehicle Charging in Distribution Grids

A simple and low-cost Power Hardware-in-the-Loop (PHIL) demonstrator is developed for the purpose of studying the impact of Electric Vehicle (EV) charging on low voltage distribution grids. An energy saving power circulating method with potential bi-directional function is proposed in this study as well. The distribution grid under test runs on a Digital Real Time Simulator (DRTS), and a controlled 3-phase voltage at one of the nodes is formed using a power amplifier. The practical setup consists of Electric Vehicle Supply Equipment (EVSE) and a system which emulates the charging behaviour of an EV, referred to as an EV emulator. These are integrated using a 15 kW back to back ac-dc converter based power router. Structure, performance and limitations of the test-bed components, communication protocols and signal processing are discussed.