电工技术学报2024，Vol.39Issue(20)：6488-6501,14.DOI:10.19595/j.cnki.1000-6753.tces.231541
基于电路分解模型的三有源桥电流有效值优化控制策略
Optimal Control Strategy for Triple Active Bridge Current RMS Based on Circuit Decomposition Model
摘要
Abstract
As an effective solution for renewable energy,electric vehicles,and energy storage flexible access to the DC grid,the triple active bridge DC-DC converter(TAB)has widespread adoption in the DC grid.The main research of TAB involves topology improvement,decoupling control strategy,modeling methodology,and soft-switching characteristics.However,the rms value of the inductor current,as an important indicator affecting the efficiency of TAB,has few optimization studies.Therefore,this paper focuses on the rms value optimization for inductor current in TAB. As the most basic control strategy of TAB,the SPS control strategy is simple and easy to implement.However,it has many shortcomings,such as few control degrees of freedom,low flexibility,increased loss,and reduced operating efficiency of the TAB.PS-PWM control strategy is usually used to optimize these objectives,but the mathematical model under PS-PWM control is complex.This paper proposes a TAB inductor current rms optimization control strategy based on the circuit decomposition model.Firstly,the operating principle of TAB under PS-PWM is analyzed,and the circuit decomposition model under PS-PWM is established.Then,the unified expressions for the power and the rms value of the inductor current at each port under different operating modes are derived.The optimized mathematical model for summing the rms value squares of the inductor current at each port of the TAB is constructed,and a genetic algorithm is applied to reduce the inductor current rms value by the optimal shift ratio.Simulation and experimental results show that the proposed analysis method and control strategy can reduce the complexity and computational difficulty of the model.The rms value of inductance current at each port is effectively reduced,and the system efficiency is improved. The following conclusions can be drawn.(1)The on-state loss of the TAB is proportional to the square of the rms value of the inductor current.The sum of rms value squares of the inductor currents is primarily related to the voltage matching ratios k21 and k31,the phase shift angle between the ports,and the duty ratio of the switching tubes.These factors provide the theoretical basis for constructing the decomposition model of the TAB circuit.(2)The circuit decomposition model based on PS-PWM control can simplify the TAB circuit analysis.The complexity and computational difficulty of optimizing the mathematical model can be reduced by introducing a genetic algorithm.(3)When the voltage matching ratio k21＞1,the sum of rms value squares of the TAB inductor current can be effectively reduced,and the power transfer efficiency of the TAB can be improved by the proposed GAOS control strategy.关键词
三有源桥/电流有效值/遗传算法/移相加脉宽调制/DC-DC变换器Key words
Three active bridges/current rms/genetic algorithm/phase shifting plus pulse width modulation/DC-DC converter分类
动力与电气工程引用本文复制引用
兰征,王雪丽,余雪萍,邹彬,刘贝..基于电路分解模型的三有源桥电流有效值优化控制策略[J].电工技术学报,2024,39(20):6488-6501,14.基金项目
国家自然科学基金项目(51807058)、湖南省教育厅优秀青年项目(22B0603)和湖南省自然科学基金项目(2021JJ50059)资助. （51807058）
