| 摘要 |
PURPOSE:To prevent the damage of a main circuit containing a converter due to the delay of protective operation while obviating the unnecessary stoppage of the converter by providing a first protective interlocking means by arithmetic operation and a second protective interlocking means capable of being operated at high speed by an electronic circuit and operating the first and second protective interlocking means in cooperation. CONSTITUTION:When a protective reliance signal is input to a controller 8, a first protective interlocking circuit 85 for a microcomputer control protective means 80 and a second protective interlocking circuit 101 by a separately mounted electronic circuit start their operation. Protective operation is conducted by an output signal from the second protective interlocking circuit 101 input at high speed in a phase control circuit 100, and a phase control circuit 81 stops a thyristor converter 3 when output signals from the first protective interlocking circuit 85 and the second protective interlocking circuit 101 satisfy the AND conditions of a logic circuit 100a and the pulse operation signal of the logic circuit 100a is input to the phase control circuit 81. |
