| 摘要 |
PURPOSE:To make it possible to perform a constant control of the voltage at a sending end of power transmission during anomaly of a communication system by using, as an input value to a constant voltage control circuit, the value which is obtained by multiplying a detected DC current by an impedance of a DC power transmission line and by adding said value to a detected DC voltage at the self-end in consideration of a voltage drop in the DC power transmission line. CONSTITUTION:If there is an abnormal state in a communication line 19 under the state of performing the constant control of a voltage at a sending end, a multiplier 43A multiplies the detected value of a DC current by an output value of a DC line impedance setter 42 and outputs the results to a summing circuit 44. Then, a circuit 44A adds the output of the multiplier 43A to a detected DC voltage of self-end and then outputs the result. On the other hand, an AND circuit 45A outputs a transfer signal based on a communication abnormal signal from a communication abnormal detector 41A and a constant control signal for sending end voltage from a selection circuit 40A. Then, a switch 46A inputs the output of the circuit 44A to a summing circuit 17A. Moreover, the circuit 17A inputs the difference between said input value and the output of a DC voltage setter 14A to a constant voltage control circuit 11A. |
