级联式双向DC-DC变换器的传统双闭环比例-积分(PI)控制方法存在调节器参数多、整定工作量大等不足,而且受限于PI控制的内在局限性,系统的动态性能不够理想。针对级联式双向DC-DC变换器的实际控制需求,综合考虑传统双闭环PI控制和模型预测控制的各自优势,将二者有机结合,构建了一套折中优化的控制方法,即在第一级双向DC-DC变换器中采用传统双闭环PI控制,而在第二级双向DC-DC变换器中设计并实现改进的模型预测控制策略。将提出的优化控制方法与传统双闭环控制和经典模型预测控制分别进行了仿真和实验比较。结果表明,相对于传统的双闭环控制,采用提出的优化控制方法可以显著改善级联式双向DC-DC变换器的动态性能,而相对于经典的模型预测控制,该优化控制方法运算量减少了45.22%。
Conventional dual-loop proportional-integral( PI) control method for cascaded bi-directional dcdc converters has some disadvantages,such as inconvenient and difficult adjustments of PI parameters. As well,due to the inherent limit of PI regulators, the dynamic performance of the cascaded bi-directional dc-dc converters can not be optimized. To fulfill the practical control demand of cascaded bi-directional dc-dc converters,an optimized trade-off control method has been proposed in this paper, which is realized by combining the conventional dual-loop PI control and model predictive control. The conventional dual-loop PI control is employed in the first stage bi-directional dc-dc converter,and an optimized model predictive control algorithm has been developed for the second stage bi-directional dc-dc converter. The proposed optimized control method has been compared with conventional dual-loop control method and classic model predictive control method through simulations and experiments. These results show that,the dynamic performance of cascaded bidirectional dc-dc converter by using the proposed optimized control method is superior to that by using conventional dual-loop control; Furthermore,compared with classic model predictive control,the computation of the proposed optimized control method is reduced by 45. 22%.