| 引用本文: | 黄守道,葛照强,肖慧慧,叶光辉.注入3次谐波控制的共模电压分析[J].电力自动化设备,2006,(9):8-11 |
| .Research on common-mode voltage with third-order harmonic injection[J].Electric Power Automation Equipment,2006,(9):8-11 |
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| 摘要: |
| 由于功率器件仅有2个开关状态,输出电压只能离散变化,造成中性点存在共模电压,对电机的运行产生负面效应。以传统两电平变频器和级联型高压变频器为例,分析了共模电压产生机理和3次谐波注入理论,在此基础上,分析注入3次谐波在提高直流电压利用率的同时,对输出共模电压造成的影响。经对比发现,共模电压新增加了3次谐波电压成分,当调制比取最大值时,共模电压中3次谐波电压幅值达到最大,加剧了共模电压对电机可靠运行的影响。通过Matlab仿真,验证了理论分析的正确性,并进一步说明了,对采用同相调制算法的变频器,注入3次谐波将导致共模电压增加。 |
| 关键词: 共模电压,3次谐波,高压变频器,级联 |
| DOI： |
| 分类号:TM714.2 |
| 基金项目: |
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| Research on common-mode voltage with third-order harmonic injection |
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HUANG Shou-dao GE Zhao-qiang XIAO Hui-hui YE Guang-hui
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| Abstract: |
| Power devices have only two states,their output voltage is discontinuous and the common-mode voltage exists in the neutral point,which will cause negative effect on motor opera-tion.With traditional two-level inverter and cascade high-voltage inverter as examples,the mechanism of common-mode voltage generation and the theory of third-order harmonic injection are studied.When the third-order harmonic is injected to raise the usage factor of DC voltage,its influence on common-mode voltage is analyzed.There is third-order harmonic component added in common-mode voltage.When maximal modulation ratio is selected,the amplitude of the third-order harmonic voltage in common-mode voltage also reaches the maximum,which may further affect the reliable operation of generators.Simulations with Matlab prove the correctness of theoretic analysis and illuminate that the third-order harmonic injection into inverter controlled by in-phase modulation will increase common-mode voltage. |
| Key words: common-mode voltage,third-order harmonic,high-voltage inverter,cascade |
