Development Of Bidirectional DC/DC Converter Based On Integreted Magnitic For UPS

High-power DC-DC converter applications with controllable bidirectional energy flow features are more needed in the field of common power supply system like industrial UPS, communication systems, distribution networks and so on. In this paper bidirectional power DC / DC converter design are focused which is applied in industrial UPS Battery part. Also the control strategy for parlllel modules flow and integreted magnetic components are discussed in depth.Based on industrial UPS battery link design requirments, half-bridge cascade structure is adopted in this project to avoid conflicts between voltage and energy flow direction. In order to achieve functional swing forward and backward BUCK-BOOST mode and controllable bidirectional energy flow. With the application of the multiple principle, in multi-branch structure the converter power rating and power density are improved and the equipment size reduced effectively.Within the multiplexed parallel structure, hard saturation IM inductors are designed. The indutcors which are proposed in this paper for high-power DC-DC converter designed in equal turn ratio to overcome the disadvantages of design derating by mutual inductance. While further satisfy the system voltage and current ripple, dynamic response, transient characteristics are further satisfied. Simulation results show that for the coupled inductor in cascade structure, the under conditions of constant power load regulation is good and current ripple meet the design requirements. Beside, the converter power loss and temperature rise as other issues have been estimated. The reasonableness of the bidirectional converter design are verified through comparison between theoretically calculated and measured efficiency data.Based on Inter modular design, parallel flow problem on high-power converter modules in this paper are focused. Namely discrete coupled inductor current average flow problems are discussed. Through PID regulator with optimized quadratic directed by changing parameters, designed Immunity and rapid response modulator for the first unit are designed, double dual-loop feedback for the later stage. For constant power load, flow control strategy without ownship are picked. Average current flow control are designed to low the affection to minimum for the latter stage. Stable output under all flow conditions for a multi-branch parallel between modules are ensured. Gap between cut through frequency bands haved avoided the impact between the double loop. Through simulation coupled inductors and parallel current theoretical are proved.Finally, experiments on 80 kW UPS prototype to verify the actual modules with coupled inductor design and flow effects.