Integral motor pump or turbine with sensorless monitoring of axial bearing wear
US12398659B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 3, 2024 |
| Grant date | Aug 26, 2025 |
| Priority date | — |
| Expiry date | May 16, 2044 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01D25/16
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
Axial bearing wear of a directly driven, axial, integral motor pump (IMP) or integral motor turbine (IMT) is monitored without use of sensors by estimating an axial rotor-stator gap according to a known dependence of the back EMF on the impeller rotation rate and the rotor-stator gap. The back EMF can be directly measured, for example between impulses of a variable frequency drive (VFD), or inferred from measurements of voltage applied to IMP stator coils and the resulting current. The rotation rate of an IMT impeller can be determined from a modulation frequency of the EMF. The rotation rate of an IMP impeller can be inferred due to its synchronicity with the applied, amplitude modulated power. A controller can record and report rotor-stator gap estimates over time, and can halt operation of the module if the estimated rotor-stator gap falls outside of a specified range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.