An integrated magnetic resonance (MR) and positron emission tomography (PET) system includes an MR scanner including a magnet that defines an opening in which a subject is positioned, a set of PET detectors disposed about the opening, a plurality of data processing units each electrically connected with a respective one or more of the PET detectors of the set of PET detectors, and a plurality of power supply modules, each power supply module being operable to generate a DC power supply for different groups of one or more of the data processing units. Each power supply module is discrete from the other power supply modules.