Split gradient amplifier for an MRI system
US5270657A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 22, 1992 |
| Grant date | Dec 14, 1993 |
| Priority date | — |
| Expiry date | Oct 22, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/3852
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A gradient amplifier for use in magnetic resonance imaging equipment employs a low voltage DC power supply connected in series between a pair of higher voltage DC power supplies, the latter supplies serving to provide increased power for rapid gradient switching and the former supply providing correction current to produce the desired voltage output. The high voltage DC power supplies preferably comprise multiple DC units which can be combined to provide finer steps of control prior to correction by the lower voltage supply. The low voltage DC power supply preferably comprise one or more linear amplifiers connected in series, or one or more switchmode amplifiers connected in series. The DC power supplies are controlled in an open loop manner from a gradient signal that designates the desired current for the gradient coil and the amplifiers are operated in a closed loop responding to to a feedback signal from the gradient coil.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.