A Novel Embedded Sensor for Partial Discharge Detection in Inverter-Fed Machines

This article presents a novel ring-shaped hybrid fractal antenna for detection of partial discharge (PD) in inverter-fed machines. PD is known as a source of degradation and lifetime reduction in the machines winding insulation. PD activity is becoming a major concern in high performance drives, especially due to the increased use of repetitive impulse voltage with short rise-time (high
dv
/
dt
) from pulsewidth modulation-controlled inverters. The proposed hybrid fractal antenna is designed and experimentally demonstrated to show a high sensitivity in the ultrahigh-frequency bandwidth of interest for PD detection as well as an ability to discriminate PD signals from other sources of high-frequency disturbances. Additionally, the proposed PD sensing solution features a unique ring-shape geometry that facilitates its physical integration into a live machine, making it suitable as a noninvasive solution for online condition monitoring and PD detection of any inverter-fed electrical machine.