A Voltage Calibration Chain for Meters Used in Measurements of EV Inductive Power Charging

TL;DR

This paper presents a detailed voltage calibration chain for measuring power in electric vehicle inductive charging systems, addressing the challenges of superimposed AC ripple and DC signals.

Contribution

It introduces a novel calibration method using synchronized circuits and a phantom power approach for accurate EV charging measurements.

Findings

Effective calibration of voltage measurement chain demonstrated.

Improved accuracy in EV inductive power measurement.

Method suitable for high-frequency ripple conditions.

Abstract

The inductive charging of electric vehicles requires specific measurement and calibration systems. In fact, the measurement of power on board involves DC signals, which are superimposed to a significant AC ripple up to or over 150 kHz, depending on the type of charging system. A calibration method that makes use of a phantom power, based on two independent but synchronized circuits, is considered, simulating the charging voltage and current. This paper describes in detail a solution in the realization of the voltage calibration chain, based on the use of a DC voltage calibrator, an injector and a voltage divider.