Characterization of electromagnetic interference conducted in DC-DC Buck Converter LED Light in accordance with CISPR 25 - Class 5

Abstract

This article describes the characterization of the conducted electromagnetic interference (EMI) generated by a work LED light (WLL) for use in forestry wheeled harvesters (FWH), with DC/DC Buck conversion topology and operating in continuous current mode. After the characterization of the conducted emissions, the development of an EMI filter is presented, for control of emission levels in accordance with CISPR 25 Class 5. The results of the time domain analysis demonstrate that the conducted EMI emissions in a WLL can cause sudden failure of the light-emitting diodes (LEDs) and FWH's radio communication systems. To solve the problem, an EMI filter is implemented and the experimental results were satisfactory. It proved effective in suppressing interference on the radio system and LED voltage levels, maintaining the light intensity of the WLL. The experimental setup for compliance tests has proved to be effective, both in characterization and in filter efficiency tests.