摘要
为实现中低压直流互联场景中串并联直流固态变压器的高效传输和灵活调压,组合CLLLC变换器模块和Buck/Boost-CLLLC变换器模块形成新的混合型串并联双向直流固态变压器(hybrid series-parallel bi-directional DC solid state transformer, HSBDCSST),使其兼具Buck/Boost-CLLLC变换器的双向灵活调压和CLLLC变换器的双向高效传输优势。同时提出了CLLLC模块的同步方波控制和Buck/Boost-CLLLC模块的改进虚拟直流电机(improvement virtual direct current motor, IVDCM)控制。其中各CLLLC模块采用同一个固定频率占空比为50%的方波进行控制以保证高效率。而对于Buck/Boost-CLLLC模块,在传统虚拟直流电机(virtual direct current motor,VDCM)控制的基础上引入直流电机额定角速度随机械功率按比例变化的环节,构成IVDCM控制策略,实现调压并改善直流变压器的惯性阻尼特性,有效提高了系统的响应速度与动态特性。最后搭建3模块串并联系统的Matlab/Simulink仿真模型及实验平台,验证了该控制方法的有效性。
To realize high efficiency transmission and flexible voltage regulation of series-parallel DC solid state transformers in medium and low voltage DC interconnection scenarios,this paper combines the CLLLC and the Buck/Boost-CLLLC converter modules to form a new hybrid series-parallel bi-directional DC solid state transformer(HSBDCSST).It has both the bi-directional flexible voltage regulation of Buck/Boost-CLLLC converter and the bidirectional high-efficiency transmission advantage of the CLLLC converter.Synchronized square wave control of the CLLLC module and the improved virtual DC motor control(IVDCM)of the Buck/Boost-CLLLC module are also proposed,in which each CLLLC module is controlled by the same fixed frequency square wave with 50%duty cycle to ensure high efficiency.As for the Buck/Boost-CLLLC module,a link that the rated angular speed of the DC motor varies in proportion to the mechanical power is introduced on the basis of traditional VDCM control.This constitutes the IVDCM control strategy,realizes voltage regulation and improves the inertia damping characteristics of the DC transformer.This effectively improves the response speed and dynamic characteristics of the system.Finally,a Matlab/Simulink simulation model and an experimental platform of the 3-module series-parallel system are constructed to verify the effectiveness of the control method.This work is supported by the Scientific and Technological Project of Henan Province(No.232102240078).
作者
王允建
张昌杰
孙星
杨森
何世豪
郭向伟
WANG Yunjian;ZHANG Changjie;SUN Xing;YANG Sen;HE Shihao;GUO Xiangwei(School of Electrical Engineering and Automation,Henan Polytechnic University,Jiaozuo 454003,China;Henan Key Laboratory of Intelligent Detection and Control of Coal Mine Equipment,Jiaozuo 454003,China)
出处
《电力系统保护与控制》
EI
CSCD
北大核心
2024年第22期93-103,共11页
Power System Protection and Control
基金
河南省科技攻关项目资助(232102240078)。
