State space feedback controller in the digital domain for an MRI gradient coil power supply

US9541618B2 · kind B2 · utility

Assignee

• KONINKLIJKE PHILIPS ELECTRONICS NV · NL

Inventors

• Thomas Scheel · Stolberg, DE
• Christian Hattrup · Würselen, DE

Key dates

• Filing date: Dec 15, 2011
• Grant date: Jan 10, 2017
• Expiry date: Mar 8, 2034

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R33/3852
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A state space feedback controller operates in the digital domain for the regulation of the current supply to MRI gradient coils from a multiple-bridge PWM power amplifier. The P1-controller includes an integration part (for the integration of the difference between the demand current and the measured gradient coil current) and a subsequent P-controlled system which in turn includes a delay compensator/stabilizer and a plant. The delay compensator/stabilizer includes a multi-path feedback loop by means of which its digital output signal is fed back through delay blocks, on the one hand, and through filter units, on the other hand. The filter units model the transfer functions of a gradient coil output filter for the gradient coil voltage and the output current of the amplifier inverter units, respectively. In the plant, a filter unit, which models the gradient coil transfer function, is connected in series to a delay chain for the delay of the measurement value of the gradient coil current.