China International Youth Conference on Electrical Engineering (CIYCEE 2020)

The online impedance serves as an essential parameter to evaluate the operating status and health condition of many critical electrical systems. Because of its non-contact nature and ease of on-site implementation, the inductive coupling approach is an outstanding method for online impedance measurement. The inductive coupling approach usually adopts a two-probe measurement setup. In some practical situations where a system under test (SUT) is exposed to significant electrical noise and power surges, the existing two-probe measurement setup lacks the necessary signal-to-noise ratio (SNR) and front-end protection to measurement instruments, which, as a consequence, makes its use challenging. To overcome this challenge, an improved two-probe measurement setup is proposed in this article. The proposed two-probe measurement setup incorporates signal amplification and surge protection modules, thereby improving its SNR and enhancing its ruggedness. By performing a number of tests that cover different frequencies and various SUTs, the accuracy and the reliability of the proposed two-probe measurement setup have been validated by experiments.

Inductive Coupling,Electrical System,Online Impedance Measurement,Two-Probe Measurement Setup