多电飞机双向直流变换器的电流应力优化策略

双向直流变换器在多电飞机电源系统中有着重要的应用,为提高双有源桥双向直流变换器效率,提出一种基于双重移相模态组合控制的优化控制策略。为降低变换器电流应力,提高变换器效率,在推导不同模态下变换器电感电流、传输功率及电流有效值数学表达式的基础上,利用拉格朗日方程求取在不同模态、不同电压调节比下使得电感峰值电流最小的移相比函数。通过仿真对比研究双重移相模态组合优化控制及单移相、拓展移相控制、双重移相单模态1控制方式下的电感峰值电流及电流有效值。对比分析表明,双重移相模态组合优化控制不仅减小了系统电流应力,而且降低了变换器电流有效值,在提高系统效率方面更具优势。

Current Stress Optimization Strategy for Bidirectional DC-DC Converter of Multi-electric Aircraft

The bidirectional DC-DC converter has an important application in multi-electric aircraft power system.In order to improve the efficiency of dual active bridge bidirectional DC-DC converter,an optimal control strategy based on dual phase shift mode combination control was proposed.In order to reduce the current stress of the converter and improve the efficiency of the converter,based on the mathematical expressions of the inductor current,transmission power and current RMS of the converter under different modes,Lagrange equation was used to obtain the phase shift function which minimizes the peak inductance current under different modes and different voltage regulation ratios.The peak current and current RMS value of the inductor under dual phase shift mode combination optimization control,single phase shift control,extended phase shift control and single mode one control mode of dual phase shift were compared by simulation.The comparative analysis shows that the dual phase shift mode combination optimization control not only reduces the system current stress,but also reduces the converter current RMS,which has more advantageous in improving system efficiency.