| 摘要 |
PURPOSE:To enable low-frequency current to be eliminated, by providing the charged section of capacitors working separately at the upper and lower steps, a band pulse filter taking out the specified frequency content of pulsating current, an inverter section suppressing higher harmonic, and the like. CONSTITUTION:An AC motor 5 is driven through a DC power source 1 via a DC reactor 2, a smoothing capacitor 3, and an inverter section 4. Then, AC content detectors 6-6', upper and lower step charged elements 7-8', upper and lower step capacitors 9-10, voltage detectors 11-11', an inverter section 12, and a DC reactor 13 are provided, and the charged elements 7-8' are controlled by a voltage establishment control circuit section, and the inverter section 12 is controlled by a control circuit section. The inverter control circuit section is provided with a band pulse filter infiltrating the frequency content only which is required to be removed from the AC waveform of the detector 6, and the frequency content output is phase-inverted by an inverter, and by the output for a command waveform, the inverter section 12 is driven and controlled. As the result, the frequency content which is required to be removed can be eliminated.
|
