Testing device for propagation characteristic of electromagnetic wave in gas insulated switchgear and testing method therefor

A testing method for propagation characteristic of electromagnetic wave in a gas insulated switchgear (GIS), comprising following steps of:

• step (1):
• replacing a disc insulator (9) between two chamber sections with a hollow cylinder and keeping a length of the chamber sections, wherein electromagnetic waves are not transmitted via the disc insulator (9), sending an ultrahigh frequency electromagnetic wave signal via an emitting antenna (2) and a partial discharge ultrahigh frequency signal generator (1), receiving an ultrahigh frequency electromagnetic wave signal via a receiving antenna (12) and an oscilloscope (11), so as to obtain electromagnetic wave signal without access to the disc insulator;
• step (2):
• installing the disc insulator (9) and repeating a process in the step (1), receiving the receiving antenna (12) and the oscilloscope (11) to obtain electromagnetic wave signal passed through the disc insulator (9);
• and
• step (3):
• respectively comparing time domain and frequency domain of the electromagnetic wave signal obtained in the step (1) with the time domain and the frequency domain with electromagnetic wave signal obtained in the step (2);
• wherein the time domain of the electromagnetic wave signal comprising three characteristics of a maximum amplitude, an average amplitude and a signal energy;
• and
• wherein to a frequency domain signal, a frequency distribution characteristic is compared;
• obtaining influence of the disc insulator on propagation characteristic of the electromagnetic wave signal by comparing the time domain and the frequency domain, so as to obtain the propagation characteristic of the electromagnetic wave signal in the GIS.