A Circular Patch Microstrip Antenna with Ultrasonic Sensing Capabilities

The generation of ultrasonic and electromagnetic signals is a key characteristic of partial discharge (PD) activity within power equipment. Existing condition monitoring methods, which depend on single-signal sensors, are limited in their ability to comprehensively assess operational integrity. To address this, we propose an sensor model combining ultrasonic and ultra-high frequency (UHF) detection capabilities. The proposed model incorporates a polyvinylidene fluoride (PVDF) piezoelectric substrate and a circular patch microstrip antenna. Simulations conducted using the High Frequency Structure Simulator (HFSS) and COMSOL show that the model achieves a voltage standing wave ratio (VSWR) of less than 5 within the 0.3-1.5 GHz range, and below 2 within the 0.4458-1.3535 GHz range. Furthermore, the model demonstrates a maximum receiving sensitivity of 58.45 dB, a minimum of 35.84 dB, and an average of 50.67 dB across the 20–200 kHz ultrasonic band, along with a displacement response across this band. These findings confirm the model's ability to simultaneously detect UHF and ultrasonic signals.