Patent · US Active

Variable frequency drive apparatuses, systems, and methods and controls for same

US9816742B2 · kind B2 · utility

2Cited by
10References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 13, 2014
Grant dateNov 14, 2017
Priority date
Expiry dateDec 1, 2035

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF25B2500/26
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

Detection of reverse rotation or operation of a refrigerant compressor is provided. In one aspect, a detection technique includes starting the compressor and determining the compressor is rotating in a reverse direction if a dome temperature of the compressor fails to exceed a first predetermined threshold at or before expiration of a first predetermined period of time following starting, the refrigerant pressure at a refrigerant inlet of the compressor remains constant for a second predetermined period of time following starting, and/or the frequency of pressure oscillations of the refrigerant at the refrigerant inlet exceeds a second predetermined threshold. Another technique for determining the compressor is rotating in the reverse direction involves analyzing a waveform associated with motor current, motor torque, or refrigerant pressure. Further embodiments, forms, features, and aspects shall become apparent from the description and drawings.

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