基于Sigma-Delta AD采样的双向有源桥变换器中变压器的直流偏置抑制  

DC Bias Suppression of Transformer in Dual Active Bridge Converter Based on Sigma-Delta AD Sampling

作　　者：欧朱建 袁建华 姚文熙[2] 王庭康 OU Zhujian;YUAN Jianhua;YAO Wenxi;WANG Tingkang(State Grid Nantong Power Supply Company,State Grid Jiangsu Electric Power Co.,Ltd.,Nantong 226006,China;College of Electrical Engineering,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]国网江苏省电力有限公司南通供电分公司,江苏南通226006 [2]浙江大学电气工程学院,浙江杭州310027

出　　处：《电机与控制应用》2023年第10期17-23,38,共8页Electric machines & control application

基　　金：国网江苏省电力有限公司重点科技项目(J2022019)。

摘　　要：双有源桥(DAB)变换器兼具高效和高功率密度,且其能量可双向流动,从而得到广泛应用。DAB变换器易因电路参数、驱动信号不对称等因素造成磁不平衡,进而影响电路正常稳定工作。因此,设计了一种变压器绕组的直流偏置电流检测控制策略。该策略通过采样电阻和delta-sigma(Δ-Σ)调制将电流转换为1位数据流,采样电阻放置在H桥直流端,可分别获得绕组正半周和负半周中电流平均值,相减可得绕组电流直流分量。同时,设计了一种DAB的直流电流抑制方法,通过设计控制器以实现微调任一桥臂的占空比来调节H桥输出电压的直流分量。最后,通过Matlab仿真验证了直流偏置电流检测与控制策略的有效性。Dual active bridge(DAB)converters has been widely used because of its high efficiency,high power density and bidirectional energy flow.DAB converters are prone to cause magnetic imbalance due to factors such as circuit parameters and asymmetric driving signals,which would affect the normal and stable operation of the circuit.Therefore,a DC bias detection and control strategy for transformer windings is proposed.This strategy uses the sampling resistance andΔ-Σmodulation,which can convert the current into a 1-bit high-speed data stream,and a sampling resistor is placed at the H-bridge DC end.From this,the average value in the positive and negative half cycles of winding current can be obtained,and the DC component of winding current can be obtained by subtracting it.At the same time,a DC suppression method for DAB is designed,which adjusts the DC component of the Hbridge output voltage by designing a controller to tune the duty cycle of any bridge arm.Finally,the effectiveness of DC bias current detection and control strategies has been verified through Matlab simulation.

关 键 词：SIGMA-DELTA调制 双有源桥 双向变换器 直流偏置 三移相 

分 类 号：TM46[电气工程—电器]