| 摘要 |
PURPOSE:To provide a method of detecting a single-side operation of a thyristor inverter. CONSTITUTION:The output voltage feedback value of a power inverter unit 3 and the output power setting value of a inverter are always compared with each other. If one of thyristors of which the switching devices of the power inverter unit 3 is broken down and the inverter is in the state of a single-side operation, one of DC voltage waveforms is lost and an average DC voltage is about a half of a normal DC voltage. At that time, the compared value is twice the set value of the same output power. Therefore, if the output power setting value and the output voltage feedback value are compared with each other and the difference between them exceeds a certain value, the single-side operation is detected, so that a countermeasure which avoids a secondary damage can be carried out quickly. |
