Phase-shifted Pulse Width Modulation (PWM) technique is implementable in stacked and parallel configuration of the H-bridge gradient amplifiers. However, in the gradient array systems where one stage amplifier is sufficient to drive each element, phase-shifted PWM is not feasible. In this work, similar technique is implemented by utilization of the coupling between the elements of the array and finding the optimized phases for each channel in order to have minimum current ripples. This method is tested for different gradient fields and high ripple reduction percentages achieved both in simulations and experiments.
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