| 摘要 |
PURPOSE:To improve power factor and efficiently suppress higher harmonic current contained in input current from power supply. CONSTITUTION:In the converter section 5 of an inverter 2, a current limiting means R composed of a resistor is connected to a smoothing capacitor C in series. The connection between the smoothing capacitor C and the current limiting means R, is connected to a regenerating means 20, composed of a diode, that feeds regenerative current from a motor 3 or the like to the smoothing capacitor C, bypassing the current limiting means R. The smoothing capacitor C having a small capacitance is used to improve power factor and suppress higher harmonic current. The small capacitance of the smoothing capacitor C degrades the smoothness of d.c. voltage from a rectifier diode D and allows ripple current to pass through the smoothing capacitor C. However, the current limiting means R limits such ripple current, which prevents the smoothing capacitor C from being overheated. |
