The high-current delivered by a dedicated power supply is the condicio sine qua non to obtain the strong magnetic field produced by superconducting magnets. The end goal of such power supply is to control the current, very precisely, across this distinctive kind of load. To this extent, the topology and a specific mode of operation that fit the requirements is analysed and presented in this paper. To obtain a contemporary power supply design, a design optimisation of the overall system with respect to efficiency and volume is carried out. Considering the modularity specification, the system is split into elementary building blocks and one optimally designed unit is practically implemented and verified against predictions from the design tool. In sum, this paper provides the comprehensive design process for a modern 2-quadrant high-current low-voltage DC/DC power supply.