摘要
数字式闪变仪多采用均方根(RMS)值作为输入,经傅立叶变换得到电压波动频率和幅值,再通过查表的方式直接计算出瞬时闪变视感度。然而以上过程多采用数值计算,缺乏准确的解析表达式。为此采用了动态相量法,对单一频率的正弦调制工频电压进行分析,得到RMS电压频谱的解析表达式,并由此计算得到一组新的使得瞬时闪变视感度为1的频率与RMS电压波动对照表,分析表明,随着频率的增加,其结果与调幅波电压波动差距较大,因此宜采用基于RMS的新的对照表,以正确计算闪变值。最后将以上分析扩展到多调幅波频率的情况,结论一致。
The digital flicker meter often calculated the frequencies and amplitudes of voltage fluctuation by Fourier transform dealing with the RMS values of a voltage waveform and then calculates the instantaneous flicker sensation level directly by checking table.Yet the above process was usually completed by numerical calculation,lack of accurate analytical expression.So dynamic phasor approach was adopted to calculate the analytical expression of the RMS values spectrum of power frequency voltage modulated by single frequency sinusoidal wave,and a new comparison table on frequencies and corresponding voltage fluctuations of RMS,which make instantaneous flicker sensation level to be one,is obtained.The analysis show that the voltage fluctuations of RMS values are quite different from those of modulation wave with the increase of frequency.The new comparison table based on RMS values should be adopted to calculate flicker value correctly.Finally,consistent conclusions can be drawn when the above analysis is extended to multiple modulation wave frequencies.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2010年第5期1293-1298,共6页
High Voltage Engineering
基金
国家自然科学基金(50747043)
福建省科技计划重点项目(2007H0022)~~
关键词
电压闪变
频率特性
动态相量
电能质量
信号处理
检测
voltage flicker
frequency characteristics
dynamic phasors
power quality
signal process
detection
