基于GTEM的局部放电UHF标定的场强溯源研究

采用GTEM小室标定局部放电特高频(UHF)检测系统的可测场强,已作为衡量检测系统性能的关键指标被纳入电力标准。目前在计量领域,国内外尚且没有对脉冲场强进行一致性测量的标准,研究局部放电特高频标定的场强溯源十分必要。为此,文中采用向GTEM小室注入扫频和脉冲信号的方式,利用单极探针的传递函数和电压响应,计算了标定场强的波形和幅值;在扫频情况下,采用德国Narda场强计的实测与单极探针计算结果进行对比,两者误差在8%以内,验证了单极探针对GTEM小室内稳态场强标定的正确性;在脉冲注入情况下,采用CST仿真与单极探针结果进行了对比分析,场强峰值误差为1.7%,论证了单极探针对于GTEM小室内脉冲场强标定的正确性。研究成果为局部放电特高频检测系统脉冲场强标定的溯源奠定了基础。

Research of Traceability of UHF Calibration Field Strength for Partial Discharge Based on GTEM

The measurable electric field strength of PD UHF detection system calibrated by GTEM cell has been included in the electricity standard as a key indicator to evaluate the performance of the detection system.Presently,there is no consistent measurement standard for the pulse electric field in the metering territory at home and abroad,therefore it is necessary to research the traceability of electric field calibration for PD UHF detection system.In this paper,by injecting sweep frequency and pulse signal to GTEM cell,the waveform and amplitudes of calibrated field strength are calculated using the transfer function and voltage response of the mono-pole antenna.Under the condition of sweep frequency,the results measured with Narda field strength meter are compared with the calculation using the model of mono-pole antenna,and the error between them is within 8%,which verifies the correctness of calibration of the steady state electric field in the GTEM by the use of mono-pole antenna.While under the condition of injecting pulse signal,the simulation results of CST are compared with the calculation results,and the error of the peak value of eclectic field strength between them is 1.7%,which verifies the correctness of calibration of the pulsed electric field in the GTEM by use of mono-pole antenna.The research results of this paper lay the foundation for studying traceability of calibrating the pulsed electric field strength by PD UHF detection system.GTEMUHFfield intensitymono pole antennasCST simulation.