关于晶闸管交-交变频器输出力矩偏低和低频振荡问题的研究

Research on the low output torque and low-frequency oscillation of the SCR AC - AC converter

晶闸管交-交变频器输出力矩低和低频振荡是具有共性的2个问题,该文针对这2个问题,从零电流检测灵敏度和触发电路同步移相电压的选取2个方面进行了较详细的原因分析,并提出了解决方法。实践表明,零电流检测灵敏度正确选择是解决交-交变频器输出力矩偏小的关键所在。同样是余弦控制,采用正弦波移相触发电路交-交变频器的输出电流正弦度更好,有效抑制了输出的低频振荡。

The Thyristor AC-AC converter with low output torque and low-frequency oscillation has two common problems,for these two issues,this paper analysis the cause and status the solution from the sensitivity about the detection of zero-current and the selection of the synchronization phase-shifting trigger circuit.Practice shows that correct choicing the sensitivity about the detection of zero-current is the key of to solving low output torque of the AC-AC converter.Similarly,about the cosine control,we can acquire better sine degrees of output current using sine wave phase-shift trigger circuit of AC-AC inverter,effectively inhibit the low-frequency output oscillations.