Patent · US Expired

Power control unit

US5880578A · kind A · utility

23Cited by
7References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 10, 1997
Grant dateMar 9, 1999
Priority date
Expiry dateSep 10, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05B39/02
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

In a power control unit for controlling a power supply to a load connected to an AC power source by switching on half cycles, following three modes are carried out in the order of presented: a first control mode for continuously supplying a power which is composed of a plurality of half cycle switching waveforms of a first polarity to said load; a second control mode for continuously supplying a power which is composed of a plurality of half cycle switching waveforms of a second polarity to said load, said second polarity being different from said first polarity; and a third control mode for supplying a power of a half cycle of said first polarity and a power of a half cycle of said second polarity to said load in turn. This arrangement can attain an effect that both the harmonic noises and the flickers caused by a rush current are reduced.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.