Novel Dynamic Power Balancing Solution for Minimization Overdesigning in Military Aircraft Power System Architecture

In the existing power system architecture of military aircraft (such as F-35), electrical loads are fed from two 270V-HVDC buses. These two HVDC buses are completely isolated from each other. In existing architecture, there is no possibility of power transfer between the two buses. This inability reflects as overdesigning of the system to meet the dynamic loads and possible power quality deterioration during operation (occurring due to unequal loading of the two HVDC buses). This paper attempts to address this inability by introducing the concept of dynamic power balancing between the buses. As military aircraft design criteria are sensitive to weight and size, the introduction of the proposed feature must not add additional weight to the system. To ensure this, the authors have studied the existing architecture and have attempted to replace the two 270V to 28V Dual-Active Bridge (DAB) converter (used for charging the 28V battery) with the proposed Triple-Active Bridge (TAB) converter. This converter must be capable of achieving power balancing in addition to the conventional 28V battery charging operation. To achieve this, a modulation strategy to achieve bidirectional power flow and soft-switching is also discussed. Simulation results verifying the feasibility of the proposed converter and control are also presented.