Input parallel output parallel (IPOP) DC/DC system is widely utilized in many occasions like data center and hybrid electric vehicle (HEV). However, the efficiency characteristics of different converters usually differs from each other, and the conventional control strategy has difficult to realize efficient conversion of overall power of the system. To address this issue, Buck converter is taken as the module and whose efficiency model under current continuous conduction mode (CCM) is presented. Meantime, parameter identification method based on least square (LS) algorithm is proposed as well. In order to realize the efficiency optimization of the whole parallel system, the constraint conditions of each module are analyzed, and the current distribution calculation method based on sequential quadratic programming (SQP) algorithm for the parallel system is introduced. On this basis, a control strategy of proportional current distribution (PCD) is proposed, which not only ensures that the parallel system can always run as efficiently as possible under different loads, but also realizes the flexible switching between the current-sharing mode and current distribution mode. Finally, the simulation and experimental results prove that the proposed method can achieve 4.46% higher efficiency than conventional method within the given power range of each converter, and realize the efficiency optimization of the IPOP DC/DC system to the greatest extent.

中文翻译：

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HEV 的 IPOP DC/DC 系统效率优化


输入并行输出并行（IPOP）DC/DC系统广泛应用于数据中心和混合动力电动汽车（HEV）等多种场合。然而，不同变换器的效率特性通常各不相同，传统的控制策略难以实现系统整体功率的高效转换。为了解决这个问题，以Buck转换器为模块，提出了电流连续导通模式（CCM）下的效率模型。同时，还提出了基于最小二乘（LS）算法的参数辨识方法。为了实现整个并联系统的效率优化，分析了各模块的约束条件，提出了基于顺序二次规划（SQP）算法的并联系统电流分布计算方法。在此基础上，提出了比例电流分配（PCD）控制策略，不仅保证了并联系统在不同负载下始终能够尽可能高效地运行，而且实现了均流模式与电流模式之间的灵活切换。分配模式。最后，仿真和实验结果证明，在给定的各变换器功率范围内，所提方法比传统方法可以实现4.46%的高效率，最大程度地实现IPOP DC/DC系统的效率优化。