Hydraulic systems with variable speed drives
US10822772B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 2, 2018 |
| Grant date | Nov 3, 2020 |
| Priority date | — |
| Expiry date | Dec 21, 2038 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B2211/88
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
Provided are hydraulic systems comprising variable speed drives coupled to hydraulic pumps and methods of operating such systems. The drive speed is controlled based on the position of a hydraulic servo-control valve in order to reduce the flow through a bypass line. Specifically, the drive speed may be decreased as the valve is opening and sending a greater portion of the hydraulic fluid into the bypass line. This approach allows to reducing losses in the bypass line thereby increasing the overall efficiency of the hydraulic system. The position of the hydraulic servo-control valve may be determined using a position sensor or a flow sensor. Alternatively, the position may be estimated by increasing the drive speed and monitoring the pressure change in the hydraulic actuator. The differential pressure-speed ratio obtained during this speed increase is compared to a calibration set of values corresponding to different valve positions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.