Magnetic resonance imaging apparatus

A magnetic resonance imaging apparatus, comprising:

• a gradient magnetic field power supply including an amplifier configured to amplify an input signal based on information of a gradient magnetic field waveform and output the amplified input signal to a gradient coil, a power supply device configured to supply power to the amplifier, and a capacitor bank configured to supply power, together with the power supply device, to the amplifier;
• a voltmeter configured to measure a voltage of the capacitor bank;
• storage circuitry to store a plurality of parameters of a circuitry model that is equivalent to the gradient coil, the parameters including a resistance value corresponding to a resistance element in the circuitry model, a mutual inductance corresponding to two coils that interact magnetically in the circuitry model, and a self-inductance in the coil itself in the circuitry model;
• and
• processing circuitry configured to calculate frequency characteristics of an impedance of the gradient coil, based on a voltage variation of the capacitor bank measured by the voltmeter, adjust the parameters in the circuitry model, based on the calculated frequency characteristics of the impedance, and control imaging in accordance with the calculated frequency characteristics.