Patent ID: 10302719

Abstract:
The present invention provides a gradient amplifier (300) for a magnetic resonance imaging system, comprising: a power amplifier (310) configured to supply a gradient coil current to a gradient coil (330); a passive filter (320) oupled to the power amplifier and configured to damp a harmonic component of the gradient coil current, wherein an oscillation current caused by oscillation of the passive filter (320) is present in the gradient coil current; and an active power filter coupled between the passive filter and the gradient coil and configured to generate a compensation current to compensate the oscillation current. Through incorporating an active power filter to compensate the oscillation current caused by the oscillation of the passive filter, the power consumption for attenuation of the oscillation current may be decreased prominently, the compensation result for the oscillation current may not be substantively affected by the variations of the gradient coil parameter, and reliability of the gradient amplifier is improved.