| 摘要 |
PURPOSE:To reduce the loss due to switching and to control the efficient pulse width modulation by controlling the modulating triangular shape of a chopper according to a modulation factor so that amplitude of a ripple current of a load becomes substantially constant. CONSTITUTION:The voltage e1 of a DC power source 1 and the voltage e2 of a load capacitor 4 are detected, e1-e2 is calculated by a voltage detector 21 to limit the positive side of a voltage e103 by a diode 22. The negative side of the voltage e103 is limited by a diode 23 to the e2. Thus, a triangular wave e12 becomes a time in integrating the e2 at a rise and a waveform in integrating e1-e2 at a fall. Thus, the frequency (f) of the voltage e12 is controlled to enable a uniform pulse width modulation so that a ripple current flows to a reactor 3 always becomes constant. |
