單周期控制三相PWM整流器在不對(duì)稱(chēng)電網(wǎng)下的研究

摘要：傳統(tǒng)的矢量模式單周期控制三相PWM整流器是基于對(duì)稱(chēng)電網(wǎng)系統(tǒng)下研究的，功率因數(shù)約為1，輸入諧波低，且與雙極型單周期控制相比，具有更低的開(kāi)關(guān)損耗。當(dāng)三相電網(wǎng)不對(duì)稱(chēng)時(shí)，三相輸入電流跟蹤電網(wǎng)電壓的非零序分量，采用傳統(tǒng)電網(wǎng)電壓選擇矢量區(qū)間不能保證三相PWM整流器具有較低的開(kāi)關(guān)損耗，且在電網(wǎng)極端缺相故障時(shí)，系統(tǒng)不能正常工作。本文采用電網(wǎng)電壓非零序分量選擇矢量區(qū)間，并對(duì)矢量區(qū)間狀態(tài)進(jìn)行分析比較，結(jié)果證明所采取的方法能保證系統(tǒng)在任何情況下開(kāi)關(guān)損耗最低。最后對(duì)三相PWM整流器工作于不對(duì)稱(chēng)電網(wǎng)情況下進(jìn)行了仿真研究，仿真結(jié)果表明采用電網(wǎng)電壓非零序分量選擇矢量區(qū)間能保證電網(wǎng)電壓在缺相故障時(shí)系統(tǒng)仍能正常工作，并且所采用的單周期控制同時(shí)滿(mǎn)足對(duì)稱(chēng)電網(wǎng)系統(tǒng)。 敘詞：單周期控制,不對(duì)稱(chēng)電網(wǎng),三相PWM整流器,非零序分量 Abstract：Research on three-phase PWM rectifier based on traditional vector model one-cycle control (OCC) is in balanced systems, which achieves unity power factor and low THD. And compared with bipolar mode one-cycle control, vector model one-cycle control has minimum switching losses. In unbalanced systems, three-phase input current track the non-zero sequence phase voltages. Selection region based on voltages cant ensure minimum switching losses and handle the extreme unbalanced system where one phase voltage is entirely zero. This paper employs the non-zero sequence phase voltages for region selection, and analyses vector region states, as a result, analysis verify the proposed OCC vector controller can ensure minimum switching losses in the any case. Finally, the simulation results show OCC controller with the non-zero sequence phase voltages for region selection ensure the system reliably work under extreme unbalance conditions, and also satisfy the balanced systems. Keyword：OCC unbalanced system three-phase PWM rectifier non-zero sequence