Design and Cost Analysis of a Dual Motor Controller for Marine Cooling Systems

As the marine industry shifts toward electric propulsion systems, there is increasing demand for efficient, silent, and cost-effective thermal management solutions. This thesis addresses the design and cost optimization of a dual motor controller for seawater pumps used in Xshore’s marine cooling systems. The goal is to replace two independent motor driver PCBs with a single unit capable of controlling both pumps simultaneously, thereby reducing cost, volume, and complexity. The proposed solution was designed and simulated using PSpice for TI, with performance compared against the existing single-motor solution. A simplified model of a brushed DC motor and PWM-based driver circuit was used. Cost analysis was performed by soliciting quotes from several manufacturers in Sweden and China. Results indicate that a dual-motor controller can reduce per-boat PCB cost by up to 85% compared to the current setup, depending on the supplier. While simulations validate the basic functionality of the proposed design, simplifications—such as omitted feedback and fault-handling logic—highlight the need for further development before commercialization. Overall, switching suppliers offers immediate savings, while further optimization through a dual-motor design presents long-term benefits with some added complexity.