Power supply for an inductive user, particularly a gradient coil

US4733342A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Albert Mueller · Aschaffenburg, DE
• Ingemar Neuffer · Erlangen, DE

Key dates

• Filing date: Jun 4, 1987
• Grant date: Mar 22, 1988
• Expiry date: Jun 4, 2007

Classification

• Technology area (CPC H): Electricity
• CPC primary: H02M7/483
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

Exactly defined current pulses having high edge steepness and high final value are required for the pulse-like generation of high magnetic fields in inductive users. Particularly in nuclear magnetic resonance tomography, such pulses serve the purpose of building up a topically variable magnetic field with an optimally linear field strength gradient. A power supply for generating such current pulses includes a series connection of a stepping voltage switch and a variable voltage source, whose resultant output voltage is applied to the inductive by a voltage commutator user with a suitable operational sign for the build-up or dismantling of the individual pulses. A switching and regulating circuit controls the stepping switch, the variable voltage source and the voltage commutator dependent on prescribed rated curves of the pulses, such that the pulses have a rise and decay time independent of the final value.