The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 12, 1991
Filed:
Apr. 20, 1990
Hidetoshi Kanazawa, Fujinomiya, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
In an adjustable a.c. power supply for an air-conditioner system, comprising a first frequency converter for driving a compressor motor of a first air-conditioner, a second frequency converter for driving a compressor motor of a second air-conditioner, and a common a.c. power supply for delivering a.c. power to both frequency converters, a rectifier included in at least one frequency converter is constructed as a controllable rectifier and subjected to phase-control so that a synthetic higher harmonic current of the two frequency converters as viewed from the a.c. power supply is reduced. By conducting phase-control of plural controllable rectifiers in a manner that, e.g., one rectifier has a phase-control angle of zero degrees and the other rectifier has a phase-control angle of 30 degrees, load current from the a.c. power supply is permitted to have a waveform closer to a sine wave, i.e., a waveform in which higher harmonic components are further reduced.