| 摘要 |
PROBLEM TO BE SOLVED: To improve power factor and remove higher harmonics by connecting a group of LC-type filters to a semiconductor switch that is opened/closed according to the output signal from a control unit that detects the intermittently varying current on the load side and then operates, detecting the composite current of the load current and the LC-type filters on the power supply side, and thereby driving a PWM inverter. SOLUTION: The load current of an alternating-current power supply system e with a load Z where current intermittently varies connected, is detected on the load side CT1, and the output signal is input to a control unit CX. A semiconductor switch SR opened/closed according to the output signal of CX is connected in parallel with a load Z. A group of LC filters comprising reactors L1-Ln and capacitors C1-Cn series connected is connected with SR. A PWM inverter TV, which is driven by a control unit CY that detects the synthetic current of the load current and the LC-type filters and operates according to the current signal on the power supply side CT2, is connected in parallel with the input end of the power supply system. This forms hybrid-type compensating equipment, which removes unwanted higher harmonics and compensates the reactive power of fundamental waves. |
