Development of a Sensor System for Load Monitoring in the Electrical Grid to Support E-Mobility Charging

Continuing the conceptual work published in [1] from the Energy ECS [2] subproject for the monitoring of electrical distribution grids, an initial design for a retrofittable autonomous current sensor system for the low-voltage distribution network is presented in this paper. The sensor system is capable of measuring the currents and their phase in all conductors of a 3-phase energy grid of cables going into or out of distribution cabinets and is intended for monitoring loads and detecting overloads due to extensive charging of electrical vehicles (EV). Additionally, electrodes for monitoring the voltage have been designed to provide a rudimentary voltage measurement for the phase calculation of the current. The System has been developed to be self-sufficient with inductive energy harvesting, providing a maintenance free solution. For this, an overcurrent and over voltage protection for the electronics was implemented, according to the requirements discovered in our previous works. In this paper, the concepts and designs for the autonomous current sensor are described and first results of its performance in the laboratory are shown.