直流电晕放电无线电干扰随机时域计算模型研究

Stochastic Time Domain Calculation Model for Radio Interference from DC Conductor

直流输电线路电晕放电过程中会在空间中产生随机的无线电干扰脉冲信号,目前针对电晕放电无线电干扰的测量与预测计算主要基于频域方法,并未反映出无线电干扰的时域随机脉冲特征。为此,该文在实验室搭建了直流单根导线电晕放电无线电干扰时域测量平台,采用鞭形天线实现了对正极性直流导线电晕放电无线电干扰时域特性的测量,结合无线电干扰脉冲波形特征,分析获得了脉冲波形参数(幅值、重复频率、上升时间、持续时间)的统计特性。基于统计特性,结合无线电干扰双指数函数脉冲波形建立了高压直流单根导线电晕放电无线电干扰随机时域计算模型,模型中包括随机脉冲信号产生、脉冲衰减、场强信号计算及场强信号重构,将该模型产生的无线电干扰时域波形准峰值响应值与不同测量结果进行对比,结果表明计算误差小于2dB,验证了所提模型的有效性。

The stochastic radio interference pulses can be generated from the corona discharge from DC transmission lines.At present,the measurement and prediction of radio interference were mainly based on the method in frequency domain,which cannot reflect the stochastic pulse nature characteristics of the coronagenerated radio interference.In this paper,a time domain measurement platform for DC corona radio interference from single conductor is built in the laboratory.The time domain measurement of DC corona generated radio interference from positive single conductor is realized by using time domain whip antenna.The statistical characteristics of radio interference waveform parameters,including amplitude,repetitive frequency,rise time and duration time,are analyzed in detail.Based on the time domain statistical characteristics,the stochastic time domain prediction model of radio interference from single conductor is established.In the model,the generation of stochastic pulses,attenuation of pulses,calculation of electric field in time domain and the construction of electric field pulses are included.The validity of the model is verified by comparing the quasi-peak values of the calculated results and measurement results in which the difference between them is less than 2dB.