A multi frequency point broadband compound antenna for partial discharge detection in gas insulated switchgear

Abstract

In order to meet the requirements of the miniaturized and wide-band antennas for ultra-high frequency (UHF) detection method, a multi frequency point broadband compound antenna for detecting partial discharges (PD) of gas insulated substations (GIS) was designed. Firstly, through the analysis of the principle of miniaturization and broadbandization of the compound antenna, the meander technology was used to realize the miniaturization of the antenna, the multiple radiation unit technology was used to broaden the detection frequency band of the antenna, and the HFSS simulation software was used to simulate the design of the compound antenna. Then we made the antenna object according to the optimized simulation results, and the voltage standing wave ratio (VSWR) of this antenna was tested by vector network analyzer. Finally, the GIS PD test system was built in the laboratory to conduct the actual measurement research on the antenna. The test results show that: The compound antenna has the characteristics of miniaturization, high gain and multi-band. In the frequency range of 1.0 GHz to 3.0 GHz, its VSWR is less than 2, has a wide frequency range, can record most of the PD information. With the increase of frequency, the compound antenna gain is gradually increasing, and the maximum gain of the antenna can reach 6.5 dB, which can effectively receive weak UHF signals. The proposed antenna is quite promising for PD on-line detection applications.

Experimental Study on the Compatibility of PD Flexible UHF Antenna Sensor Substrate with SF6/N2

“…At present, all newly commissioned GISs of 220 kV and above in China's power grid companies are installed with UHF detection systems or reserved with UHF detection interfaces. According to the installation position, UHF antenna sensors for GIS PD detection can be divided into two types: built-in and external [8][9][10]. External UHF antenna sensors will be affected by the serious attenuation of electromagnetic wave signals caused by outward PD leakage due to the GISs' own metal shell structure and the influence of the corona interference signal and mobile communication signal in the external environment, resulting in inadequacies in its sensitivity to the PD in the GIS, especially in intermittent PD signal sensing.…”

On-Line Partial Discharge Monitoring System for Switchgears Based on the Detection of UHF Signals

“…The UHF method can effectively avoid invalid electromagnetic waves such as GSM signals and corona signals in the switchgears. The UHF PD detection method has advantages in interference immunity, detection sensitivity and bandwidth of response frequency [13]. However, high requirements are needed for data measurement, and the sampling frequency should be higher than GHz, which is difficult and costly.…”

A Miniaturized Wideband Planar Bow-Tie Slot Antenna with Asymmetric CPW

“…A broadband bow-tie antenna fed by a Γ-shaped strip balun is proposed, which exhibits a good impedance bandwidth of approximately 93.3% for VSWR ≤2 ranging from 1.35 to 3.71 GHz [11]. A compound antenna composed of plane Archimedes spiral wire, sine wave spiral wire, and bow-tie antenna, which is fed by the exponential gradient microstrip balun is proposed with a wide band range of 0.95 to 3.0 GHz [12]. Based on SIW, an asymmetrical bow-tie-shaped cross slot radiates circularly polarized waves at two different frequencies with opposite senses of polarization [13].…”