Method and apparatus for antisurge control of turbocompressors having surge limit lines with small slopes
US5908462A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 6, 1996 |
| Grant date | Jun 1, 1999 |
| Priority date | — |
| Expiry date | Dec 6, 2016 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04D27/0207
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A turbocompressor's Surge Limit Line, displayed in coordinates of reduced flow rate (q.sub.r) and reduced head (h.sub.r), can be difficult to characterize if the slope of the line is small; that is, nearly horizontal. And it can be especially difficult to characterize if the surge line exhibits a local maximum or minimum, or both. This is often the case with axial compressors having adjustable inlet guide vanes, and for centrifugal compressors with variable inlet guide vanes and diffuser vanes. With their prime objective being the prevention of surge-induced compressor damage and process upsets, antisurge control algorithms should compensate for variations in suction conditions by calculating both the operating point and the Surge Limit Line, utilizing specific (invariant) coordinates derived by using the notations of similitude or dimensional analysis. The result is that the surge limit is invariant (stationary) to suction conditions. This disclosure describes a new method of antisurge control for turbocompressors, which uses combinations of invariant coordinates that differ from those revealed in the prior art. Subsequently, the key to this invention is that any combination (line…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.