| 摘要 |
PURPOSE:To regulate a power factor stepwise to improve the accuracy by providing a control means which controls the gate of a semiconductor switch in accordance with the detection signal of a detecting circuit to adjust the magnitude and the phase of the current, which is supplied from a main circuit to a system, in such direction that the power factor is one. CONSTITUTION:The lead/delay polarity of the power factor and the magnitude of a reactive power are detected as a signal L/D and a signal vD respectively by a detecting circuit 9 in accordance with a system voltage (v) and a current (i) in the state of feeding from a power source to a load 2. The current supplied from the main circuit to the system is set in the delay/lead direction by the signal L/D, and the magnitude of the current is set by the signal vD. A DC current ID flowing to a DC reactor 5 is set as the output of a control circuit 14. The control factor and the phase of a PWM waveform are adjusted on a basis of these set values, and a power factor regulated output is obtained in the main circuit by the control of thyristors 4U-4Y, and power factor one is obtained when viewing the load 2 and a power factor regulating circuit, that is, reactive power zero is obtained. Thus, the power factor is regulated continuously with a simplified device and this device is superior in accuracy. |
