High-bandwidth high-power gradient driver for magnetic resonance imaging with digital control

Gradient coils for magnetic resonance imaging (MRI) require large currents (> 500 A) for the gradient field strength, as well as high voltage (> 1600 V) for fast slew rates. Additionally, extremely high fidelity, reproducing the command signal, is critical for image quality. A new driver topology recently proposed can provide the high power and operate at high switching frequency allowing high bandwidth control. The paper presents additional improvements to the new driver architecture, and more importantly, describes the digital control design and implementation, crucial to achieve the required performance level. The power stage and control have been build and tested with the experimental results showing that the performance achieved with the new digital control capability, more than fulfills the system requirements

[1]  G. Stanley,et al.  Precision DC-to-AC power conversion by optimization of the output current waveform-the half-bridge revisited , 1997, PESC97. Record 28th Annual IEEE Power Electronics Specialists Conference. Formerly Power Conditioning Specialists Conference 1970-71. Power Processing and Electronic Specialists Conference 1972.

[2]  J. Sabate,et al.  High-power high-fidelity switching amplifier driving gradient coils for MRI systems , 2004, 2004 IEEE 35th Annual Power Electronics Specialists Conference (IEEE Cat. No.04CH37551).

[3]  R.S. Burwen.  Kilowatts on order (power amplifiers) , 1993, IEEE Spectrum.

[4]  Mutsuo Nakaoka,et al.  Power conversion PWM amplifier with two paralleled four quadrant chopper for MRI gradient coil magnetic field current tracking implementation , 1999, 30th Annual IEEE Power Electronics Specialists Conference. Record. (Cat. No.99CH36321).

[5]  R. L. Steigerwald,et al.  High-power, high-performance switching amplifier for driving magnetic resonance imaging gradient coils , 2000, 2000 IEEE 31st Annual Power Electronics Specialists Conference. Conference Proceedings (Cat. No.00CH37018).

[6]  O. M. Mueller,et al.  A high-frequency 4-switch GTO speed-up inverter for the generation of fast-changing MRI gradient fields , 1993, Proceedings Eighth Annual Applied Power Electronics Conference and Exposition,.

[7]  P.B. Roemer,et al.  A GTO speed-up inverter for fast-scan magnetic resonance imaging , 1992, [Proceedings] APEC '92 Seventh Annual Applied Power Electronics Conference and Exposition.

[8]  J. Sabate,et al.  Ripple cancellation filter for magnetic resonance imaging gradient amplifiers , 2004, Nineteenth Annual IEEE Applied Power Electronics Conference and Exposition, 2004. APEC '04..

[9]  Michael Joseph Schutten,et al.  Resonant power supply for magnetic resonance imaging gradient drivers , 2003, IEEE 34th Annual Conference on Power Electronics Specialist, 2003. PESC '03..

[10]  Mutsuo Nakaoka,et al.  High-frequency ZVS PWM power amplifier for magnetic-field current tracking control scheme and its design considerations , 1995, Proceedings of 1995 International Conference on Power Electronics and Drive Systems. PEDS 95.

[11]  J. Sabate,et al.  Parallel operation of switching amplifiers driving magnetic resonance imaging gradient coils , 2004, The 4th International Power Electronics and Motion Control Conference, 2004. IPEMC 2004..

[12]  William Frederick Wirth,et al.  5270657 Split gradient amplifier for an MRI system , 1994 .

[13]  Mutsuo Nakaoka,et al.  Analysis on a PWM power conversion amplifier with IGBT macro model to generate gradient magnetic fields in MRI systems , 1999, Proceedings of the IEEE 1999 International Conference on Power Electronics and Drive Systems. PEDS'99 (Cat. No.99TH8475).