Login| Sign Up| Help| Contact|

Patent Searching and Data

Document Type and Number:
Japanese Patent JPH0928080
Kind Code:

To provide an active filter circuit in which a power factor is improved or a harmonic component is superimposed.

The voltage of a commercial AC power source E is rectified by a full-wave rectifier circuit 1, and its output is boosted by a booster chopper circuit 2 and at the same time a ripple component is removed to apply the boosted voltage to a load 3. On the basis of a current direction detection circuit 8, a current value detection circuit 10, an output voltage detection circuit 11 and an input voltage detection circuit 4 in which an input voltage from a bandpass filter 5 is added by an adder 6, an arithmetic and logic unit 7 controls the gate voltage value and the turn-on period of a field-effect transistor Q1 to make it oscillate at a frequency of 40 to 100kHz. An input signal of 40 to 100kHz through the bandpass filter 5 is added by the adder 6 whereby an actual input voltage waveform becomes similar to an input voltage waveform detected by the input voltage detection circuit 4 to supply a DC voltage with a ripple component reduced and at the same time to improve a power factor.

Kumazawa, Shinji
Application Number:
Publication Date:
January 28, 1997
Filing Date:
July 10, 1995
Export Citation:
Click for automatic bibliography generation   Help
International Classes:
H02J3/01; H02M1/14; H02M3/155; H02M7/12; H02M7/217; (IPC1-7): H02M7/217; H02J3/01; H02M1/14; H02M3/155
Attorney, Agent or Firm:
樺澤 襄 (外2名)