兩種測(cè)量電壓有效值方法的比較
中國(guó)測(cè)試雜志
王堯君1，2， 劉 沖1， 蔣 慧1
（1. 南華大學(xué)電氣工程學(xué)院，湖南 衡陽(yáng) 421001； 2. 中國(guó)測(cè)試技術(shù)研究院，四川 成都 610021）
摘 要：為準(zhǔn)確測(cè)量不同頻率的交變電壓有效值，介紹兩種常用的測(cè)量方法——熱等效法和公式計(jì)算法，并分析各自的特點(diǎn)。分別利用這兩種方法搭建測(cè)量電路，對(duì)不同頻率正弦波有效值進(jìn)行測(cè)量。對(duì)測(cè)量數(shù)據(jù)進(jìn)行分析，客觀比較兩測(cè)量電路的精度和頻率響應(yīng)。分析結(jié)果表明：熱等效法適合測(cè)量高頻信號(hào)的電壓有效值，而公式計(jì)算法適合測(cè)量低頻信號(hào)的有效值，該結(jié)論為不同場(chǎng)合測(cè)量有效值的各種應(yīng)用做出參考。
關(guān)鍵詞：電壓有效值；熱等效法；公式計(jì)算法；電壓測(cè)量
中圖分類(lèi)號(hào)：TM131.3；TM933.2；TM930.114；TN431.1 文獻(xiàn)標(biāo)志碼：A 文章編號(hào)：1674-5124（2013）03-0027-04
Comparison of two RMS-DC measurement methods
WANG Yao-jun1，2， LIU Chong1， JIANG Hui1
（1. School of Electric Engineering，University of South China，Hengyang 421001，China；
2. National Institute of Measurement and Testing Technology，Chengdu 610021，China）
Abstract: In order to accurately measure the alternating voltage RMS （root mean square） value of different frequencies， two commonly used measurement methods （thermal equivalent and formula method） were introduced and their characteristics were analyzed， respectively. Each measuring circuit of these two methods was built to measure the sine waves of different frequencies. According to the analysis of the measurement data， accuracy and frequency response were compared objectively between the two measuring circuits. The results show that thermal equivalent is suitable for measuring RMS voltage of the high-frequency signal and the formula method is suitable for the low-frequency signal. It can be reference for the various applications of RMS measurements in different cases.
Key words: RMS voltage； thermal equivalent； formula method； voltage measurement
