电工技术学报2024，Vol.39Issue(10)：3082-3092,11.DOI:10.19595/j.cnki.1000-6753.tces.230316
输入串联输出并联型三电平双有源桥变换器功率与电压平衡控制策略
Power and Voltage Balance Control Strategy of Series Input Parallel Output Type Three-Level Dual Active Bridge Converter
摘要
Abstract
The dual active bridge(DAB)has the advantages of high voltage utilization,high power density,and bidirectional power transfer capability.In medium and high voltage-low voltage DC power grids,the input-series output-parallel(ISOP)DAB improves the voltage of the series side and realizes a large voltage conversion ratio.However,problems such as power imbalance between modules exist.This paper analyzes the module difference and power balance control for ISOP-DAB with a three-level neutral point clamped(3L-NPC)half-bridge. Firstly,this paper compares existing multi-module power balance methods,introduces their advantages and disadvantages,and analyzes the structure and principle of the ISOP-DAB system with a 3L-NPC half-bridge-H bridge.The reasons for the power imbalance of multiple modules are analyzed,focusing on the power transmission imbalance caused by different module parameters of the three-level half-bridge ISOP-DAB converter. Secondly,this paper analyzes the relationship between voltage,current,and power among ISOP-DAB modules.The factors affecting module consistency are discussed.The self-balancing ability of the system under disturbance is analyzed,as well as the difference in control stability between series and parallel sides under bidirectional power.A power balance control strategy without sampling voltage or current module is proposed based on TPS modulation,simplifying the sampling circuit and control design.The strategy provides a backup solution in case of sensor failure. Then,an estimation method for multi-module parameter differences is proposed.Its core idea is to inject forced components as disturbance and observe feature changes reflecting module differences.Combined with the power balance control strategy,the estimation method can be extended to N modules.Three modules are simulated in Matlab/Simulink.The constraints of the control parameter are studied to avoid overpowering.The variation trend of the power boundary margin is analyzed concerning the module number and power. Finally,an ISOP-DAB converter experimental platform with field programmable gate arrays(FPGA)controllers is designed to realize the voltage conversion from 220 V to 24 V.Under four disturbances of different sizes and plus and minus,the module difference estimation method is verified.In the output voltage range of 24 V and 10～435 W,the system can significantly improve the voltage balance on the series side under power balance control,and the efficiency is higher than 90%under most powers.关键词
输入串联输出并联型双有源桥(ISOP-DAB)变换器/多模块功率不平衡/参数差异估计方法/串联侧均压Key words
Input series output-paralle-dual active bridge(ISOP-DAB)converter/multi-module power imbalance/parameter difference estimation method/series side pressure equalization分类
信息技术与安全科学引用本文复制引用
李嘉进,马翔,谢宇帆,王天翔,舒泽亮..输入串联输出并联型三电平双有源桥变换器功率与电压平衡控制策略[J].电工技术学报,2024,39(10):3082-3092,11.基金项目
国家重点研发计划(2021YFB2601500)和国家自然科学基金(52077183)资助项目. （2021YFB2601500）
