In this paper, we present the design of a custom multiphase motor drive platform. The system integrates power electronics, sensor interface, and control modules together to facilitate research on multiphase motors. The design consists of a 12-phase inverter with isolated inline phase current sensing and isolated DC bus voltage sensing. An FPGA-based controller is used for implementing the control algorithms. The operation of the system is verified by connecting it to a bearingless motor prototype and the consequential performance improvements are highlighted.