An Improved Performance Test Method for UHF Sensors.

Effective height is used as a characterization parameter in current ultra-high frequency (UHF) sensor performance test. It describes the sensitivity of sensors to different spectral components of the signals, but is incapable of reflecting the time domain response of sensors, making it inconvenient to carry out UHF detection based on time domain signals. An improved UHF sensor performance test method, including a test system and characterization parameters is proposed. The amplitude-frequency characteristic and phase-frequency characteristic of the effective height is obtained from scattering parameters measured using a vector network analyzer. Further, by calculating the analytic impulse response, extracting three time domain parameters, including peak value of the envelope,envelope width and ringing time. The effect of the test method is discussed after a comparison test of two UHF sensor with different time domain parameters detecting a simulated partial discharge signal. The study shows that the proposed characterization and measurement system is capable of measuring the time domain and frequency domain parameters of UHF sensors and representing their behaviors under partial discharge pulse signals.