Active Thermal Management Method for Output-Parallel DAB DC–DC Converters Under Parameter Mismatches and Asymmetrical Modulation
Active Thermal Management Method for Output-Parallel DAB DC–DC Converters Under Parameter Mismatches and Asymmetrical Modulation
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DOI：
10.1109/tpel.2023.3266287
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发表时间：
2023-07
影响因子：
6.7
通讯作者：
Jinhao Shen;Jian Zhang;Xiaoyan Huang;Lin Qiu;Youtong Fang
中科院分区：
文献类型：
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作者：
Jinhao Shen;Jian Zhang;Xiaoyan Huang;Lin Qiu;Youtong Fang
在输出并联双有源桥变换器中，非对称相移调制（PSM）和参数失配会导致变换器的热不平衡，从而导致器件过早老化和失效。为了抑制热不平衡，提出了一种由改进的PSM和基于可靠性的功率分配器（PD）组成的主动热管理。首先，建立了基于双移相控制的损耗模型，分析了功率损耗，并估算了结温。其次，研究了非对称PSM下热分布不均衡的原因，并在调制过程中采用调制周期代替开关周期，进行了针对性的改进。第三，在估计温度的基础上，将IGBT温度与其失效率联系起来，建立了基于可靠性的PD模型，并得到了最优功率分配系数，以消除参数失配的负面影响。采用主动式热管理方法，可使转换器的热分布变得均衡，并提高转换器的可靠性。此外，所提出的方法不会对电性能带来不良影响。最后，通过仿真实例和样机实验验证了理论分析和结论。
In output-parallel dual active-bridge (OP-DAB) converters, the asymmetrical phase-shift modulation (PSM) and the mismatched parameters will result in the thermal imbalance, which leads to premature aging and failure. To suppress the thermal imbalance, an active thermal management consisted of an improved PSM and a reliability-based power divider (PD) is proposed. First, a losses model based on double-phase-shift control is established to analyze the power losses and estimate the junction temperature. Second, the reason for the unbalanced thermal distribution under the asymmetrical PSM is studied, and a modulation cycle instead of the switching cycle is adopted in the modulation process to make targeted improvements. Third, based on the estimated temperatures, the reliability-based PD is established by linking IGBT temperature and its failure rate, and the optimal power distribution coefficient is obtained to deal with the negative effect of the mismatched parameters. With the proposed active thermal management method, the thermal distribution becomes balanced and the converter reliability is increased. Besides, the proposed method does not bring a bad effect on the electrical performance. Finally, all theoretical analyses and conclusions are verified based on a simulation example and a prototypic experiment.