Patent · US Expired

Neutral forming circuit

US4922400A · kind A · utility

51Cited by
6References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 3, 1989
Grant dateMay 1, 1990
Priority date
Expiry dateAug 3, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02B70/10
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

Prior neutral forming circuits for use in developing a neutral voltage for loads coupled to an inverter have been unduly large and heavy or have required that the inverter be operated by a half bridge control which causes less easily filtered harmonics to be produced in the inverter output. In order to overcome these problems, a neutral forming circuit includes first and second impedances coupled together at a junction to form a series combination which is coupled across a pair of DC link conductors coupled to an inverter input and a third impedance coupled between the junction and a neutral terminal at which the neutral voltage is formed, the first through third impedances forming a resonant circuit having a resonant frequency substantially equal to the output frequency of the inverter.

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