Accurate acquisition of analog signals in power electronics: techniques, errors, and practical solutions

Abstract

Accurate acquisition of analog signals in power electronic circuits is essential for the precise characterization of switching transistors and for validating the operation of power converters. This paper aims to highlight the challenges and best practices associated with the use of oscilloscope probes in the context of measuring parameters such as switching times, transient overvoltages, and load current. Passive, differential, and current probes are comparatively analyzed, with an emphasis on their influence on the measured signal and on typical errors caused by improper connections, ground loops, and EMI interference. The paper proposes practical solutions for achieving high signal fidelity, tailored to the specific demands of power electronics. The novelty of the work lies in the integrated approach to measurement techniques and in the formulation of a set of practical recommendations for engineers involved in testing and developing switching circuits.