电力电子变压器的双有源全桥DC-DC变换器模型预测控制及其功率均衡方法
Model Predictive Control and Power Balance Scheme of Dual-active-bridge DC-DC Converters in Power Electronic Transformer
-
摘要: 该文以电力电子变压器中的输出端并联双有源（dual active bridge,DAB）全桥DC-DC变换器为研究对象,针对其动态响应慢及传输功率不均衡问题,提出一种模型预测控制策略及其功率均衡方法。同时,为了增强控制算法的灵活性,借鉴于直接电流控制的思想,提出无负载电流传感器的模型预测控制策略。最后,搭建以TMS320F28335+FPGA6SLX45为核心控制器三单元输出并联DAB的实验样机,对所提出的模型预测控制及其功率均衡方法和传统闭环电压制以及负载电流前馈控制进行对比实验验证。实验结果表明:该方法不仅可实现各个DAB模块的传输功率均衡,同时可显著地提高变换器对于输入电压突变和负载突变时的动态特性。此外,当负载电流传感器损坏或缺省时,变换器仍然可以保持良好的动态特性并实现传输功率均衡。Abstract: This paper focused on the output parallel dual active bridge（DAB） DC-DC converters in power electronic transformer（PET）. Aiming at the problem of terrible dynamic characteristics and unbalanced transmission power, a model predictive control（MPC） strategy with power balance method was proposed. Meanwhile, in order to enhance the flexibility of the control scheme, the model predictive control without load current sensor was proposed in view of the idea of direct current control. Finally, three control schemes consisting of traditional voltage closed-loop control（TVCL）, load current feed-forward control（LCFC） and proposed MPC schemes were compared in a scale-down three cells experimental platform by using TMS320 F28335+FPGA6 SLX45 as core controller. Experimental results show that the proposed MPC scheme can not only realize the equalization of the transmission power of each DAB module, but also significantly improve the dynamic response of the DAB converter when the input voltage or the load steps down and up. In addition, when the load current sensor is broken or missed, the perfect dynamic response and the balanced transmission power can still be achieved.
下载:
