| 摘要 |
PURPOSE:To increase a flicker improvement rate by letting the output of a low-pass filter rapidly follow a real value having a gentle fluctuating component, when such a condition that a quick fluctuating component of reactive power of a load comes out of the compensation range of a reactive power compensator continues the specified number of cycles. CONSTITUTION:A variable time constant adjusting circuit 16 compares a quick fluctuating component DELTAQ of reactive power Qin of a load with the upper limit value and the lower limit value of the control range of a reactive power compensator (SVC) and detects the condition that the quick fluctuating component comes out of the control range by checking the continuation of that condition the specified cycles and then makes a time constant of charging or discharging of a low-pass filter 13 smaller according to the off-direction. By this method, the output Qref of the low-pass filter 13 is allowed to quickly follow a real value having a gentle fluctuating component and thereby the quick fluctuating component DELTA is returned to the control range of the SVC. Therefore, the SVC can be controlled without being saturated by the quick fluctuating component DELTAQ and a flicker improvement rate can be increased by making an effective use of the facility capacity. |
