| 摘要 |
PURPOSE:To provide a pulse phase controller for a separately exciting power converter capable of outputting gate pulses at adequate phase even during synchronous signal loss during AC system accident. CONSTITUTION:It comprises phase difference detection means 1 for inputting synchronous signals for AC system, arithmetic amplification means 2 for filtering the output from the means 1, voltage control oscillation means 4 for outputting pulse train having a frequency proportional to the size of input signal, and a counter 5 for lowering input frequency down to system frequency, the output of the counter 5 being input to phase difference detection means 1 by using decoder. And also it includes an arithmetic processing unit 10 capable of storing and reading either input or output of the voltage control oscillation means 4 and capable of outputting stored signals by system abnormal detection signals, and transfer means for switching the output. |
