| 摘要 |
PURPOSE:To discriminate abnormality of a gate photo transmitting system of a photo thyristor converter by a method wherein a current to be made to flow in light emitting devices of plural number is varied, and conducting condition of the light emitting device to start conduction is monitored. CONSTITUTION:Prescribed voltage ET is applied to a photo thyristor converter, and current iL to be made to flow in a light emitting devices 4 of plural number contained in a gate controller is varied monitoring conducting condition of partial or on the whole of the photo thyristor converter mentioned above. Abnormality of partial or on the whole of the gate photo transmitting system is discriminated from the result obtained by monitoring magnitude of the current value and conducting condition of the light emitting device 4 to start conduction. |
