| 摘要 |
PURPOSE:To easily and accurately discriminate the cause of abnormality when the abnormality occurs by providing a fault discriminating circuit which detects a switching mode which is impossible when the operation of a power converter is considered for the gate signal and feedback signal of each semiconductor element. CONSTITUTION:In case such an abnormal gate signal that causes a short circuit in a power source is outputted from a gate logic circuit 1 and, as a result, both semiconductor elements 6a and 6b are turned on, both gate signals A and B inputted to a fault discriminating circuit 7a become '1' and the circuit 7a detects the occurrence of the abnormality. In addition, another fault discriminating circuit 7b also detects the abnormality, because both elements 6a and 6b are turned on. In case, on the other hand, a normal gate signal is outputted from the circuit 1, but abnormality occurs in gate drive circuits 2a and 2b or the elements 6a and 6b and the elements 6a and 6b are turned on while the gate signal is turned off, the circuit 7b does not detect the abnormality, but the circuit 7b does. |
