摘要
针对高压直流输电系统中发生不对称故障情况下,模块化多电平储能换流器(MMC-BESS)的荷电状态(SOC)均衡过程较长、资源配置不均、易发生过调制等影响系统安全运行的问题,提出了一种不平衡网压下模块化多电平储能换流器的新型荷电状态均衡控制策略,该方法针对于相间、上下桥臂间及子模块间提出两种不同的均衡控制策略。首先通过将桥臂输出能量作为反馈量调节相单元与上下桥臂的输出功率,调控桥臂环流中的直流分量和基频分量达到相间和桥臂间的SOC快速均衡;其次,对子模块间的SOC均衡比例增益添加限制,再通过判决函数进行判别。最后,通过验证表明,提出的控制策略与工程中常规的直接SOC均衡控制策略相比拥有更好的控制性能和响应速度。
In the case of asymmetric faults in high voltage direct current(HVDC)transmission system,modular multilevel converter-battery energy storage system(MMC-BESS)has a longer state of charge(SOC)balancing process,uneven allocation of resources,easy to occur over modulation and other security problems,a new SOC equalization control strategy for MMC-BESS under unbalanced network pressure was presented.Two different equalization control strategies were proposed for interphase,upper and lower bridge arms and submodules.Firstly,by using the output energy of the bridge arm as the feedback quantity to adjust the output power of the phase unit and the upper and lower bridge arms,the DC component and the fundamental frequency component in the bridge arm circulation were regulated to reach the SOC rapid equilibrium between the phases and the bridge arms.Secondly,restriction was added to the proportional gain of SOC balance between submodules,and then the judgment function was used.Finally,the experimental shows that the proposed control strategy has better control performance and response speed than the conventional direct SOC equalization control strategy in engineering.
作者
贺坤
王灿
张坎
陈凯平
朱汉钦
符志宇
徐雷
HE Kun;WANG Can;ZHANG Kan;CHEN Kaiping;ZHU Hanqin;FU Zhiyu;XU Lei(Hunan Changgao High Voltage Switchgear Co.,Ltd.,Changsha 410200,Hunan,China;College of Electrical and Information Engineering,Changsha University of Science&Technology,Changsha 410114,Hunan,China)
出处
《电气传动》
2022年第23期45-52,共8页
Electric Drive
基金
国家自然科学基金资助项目(51977014)
长沙市重大专项(kh2003007)。
关键词
模块化多电平储能换流器
荷电状态
不对称故障
循环电流
modular multilevel energy storage converter
state of charge(SOC)
asymmetric fault
circulating current