| 摘要 |
PURPOSE:To maintain the safety of the whole of a system, and, at the same time, to protect a semiconductor element and an AC motor with certainty by limiting the output current from an inverter section of a power converter without increasing the zero phase current. CONSTITUTION:When a current limiting start signal LMT is outputted from a limiting current detection circuit 53, a current limiting set and a reset circuit 54 output a signal SO for turning a power limiting semiconductor element off based on a discrimination signal SK from a limiting current individual charging GTR detection circuit 52 to a GTR control circuit 4. And, when the current limiting start signal LMT outputted from the limiting current detection circuit 53 is stopped, the current limiting state is reset on the basis of a zero voltage mode detection signal SJ outputted from a zero voltage mode command detection circuit 51. And, in case the overcurrent was detected by an overcurrent detection circuit 5, a command SP interrupting a gate of the power limiting semiconductor element is outputted to the GTR gate control circuit 4. |
