面向双有源桥宽增益范围的电流应力最小化策略研究

Research on Current Stress Minimization Strategy for Dual Active Bridge Wide Gain Range

针对双有源桥DAB(dual active bridge)直流变换器在变压器原副边电压不匹配时会出现电流应力急剧增大现象,提出了一种基于改进灰狼算法的最小电流应力控制策略,可以使得DAB在宽增益范围内电流应力最小。首先,在分析DAB直流变换器漏感两侧物理模型的基础上详细推导了DAB高频链数学模型,将求解电流应力转化为一个多维的含非线性约束的数学优化问题;然后,提出了一种改进灰狼算法,用于求解上述问题的全局最优解;最后,通过与3种常规控制策略的仿真对比和动态实验,验证了所提控制策略的正确性和有效性。

When the primary-and secondary-side voltages of a dual active bridge(DAB)DC-DC converter transformer do not match,the current stress therein will increase sharply.To solve this problem,a minimum current stress control strategy is proposed based on an improved grey wolf optimization(GWO)algorithm,which minimizes the current stress of the DAB in a wide gain range.First,the mathematical model of a DAB high-frequency link is deduced in detail based on analyzing the physical model on both sides of the leakage inductance of the DAB DC-DC converter.In this way,solving the current stress is transformed into a multi-dimensional nonlinear constrained mathematical optimization problem.Then,the improved GWO algorithm is proposed to find the global optimal solution of the above problems.Finally,the correctness and validity of the proposed control strategy were verified by simulations in a contrast experiment and a dynamic experiment in comparison with three conventional control strategies.