Denmark – Scanners – Gradient Power Amplifier System

DTU needs to purchase 2 separate amplifiers with power supply units, each suited for driving a uniaxial head insert gradient coil (60-70 micro-Henry) for animal and human magnetic resonance imaging (MRI), particularly for strongly accelerated hydrogen and hyperpolarized carbon-13 MRI. We aim for 3D mapping of brain metabolites with a time resolution of around a second for calculation of metabolic rates. To compensate for the low gyromagnetic ratio of carbon-13, for a 10 kHz sinusoidal gradient, the amplifiers must sustain peak voltages >1000 V and peak currents >260 A (at 20 kHz: >1000 V and >130 A). Arbitrary waveforms up to 20 kHz must be suited for normal high-performance MRI. The maximum duty cycle needs to be high (preferably 100% at 10 kHz) during the lifetime of the carbon MRI signal, i.e., 2 minutes. At least one of the amplifiers needs to be designed, built and equipped with safety measures so it can be approved for clinical use, even though CE labelling is not a requirement. Market research has shown that the only supplier of suitable gradient amplifiers that can fulfill the requirements above is IECO. Therefore, DTU intends to issue a purchase order to the company.