基于零序无功电流柔性调控的配电网覆冰线路不停电在线融冰方法  

Online Ice-melting Method Based on Flexible Regulation of Zero-sequence Reactive Current for Ice-covered Lines in Distribution Networks Without Power Outages

作　　者：张彬隆 郑泽胤 郭谋发[1,2] ZHANG Binlong;ZHENG Zeyin;GUO Moufa(College of Electrical Engineering and Automation,Fuzhou University,Fuzhou 350108,Fujian Province,China;Fujian Province University Engineering Research Center of Smart Distribution Grid Equipment(Fuzhou University),Fuzhou 350108,Fujian Province,China)

机构地区：[1]福州大学电气工程与自动化学院,福建省福州市350108 [2]智能配电网装备福建省高校工程研究中心(福州大学),福建省福州市350108

出　　处：《电网技术》2024年第2期913-922,共10页Power System Technology

基　　金：福建省自然科学基金计划项目(2023J05106)。

摘　　要：提出采用两台级联H桥变流器(cascadedH-bridge converter,CHBC)柔性调控配电网零序无功电流,实现覆冰线路不停电在线融冰。两台CHBC分别串接在覆冰线路首端和末端的接地变压器。通过末端CHBC在绝缘允许范围内调控配电网零序电压,产生的零序对地电容电流作为融冰电流流过三相覆冰导线,实现较单相接地短路电流融冰更佳的效果。通过首端CHBC调控配电网对地电容电流,实现融冰电流大小的任意调节。所提方法无需做单相接地短路,能够精准调控融冰电流,实现三相线路同时融冰。CHBC与配电网仅存在无功交互,节省了直流稳压电源容量,且功率交互之和为零,不影响配电网正常供电电压,全网负荷无需停电。仿真和实验结果验证了所提方法及控制方案的可行性和有效性。Two cascaded H-bridge converters(CHBC)are proposed to regulate the zero-sequence reactive current of distribution networks flexibly to realize the online ice-melting of ice-covered lines without power outages.The two CHBCs are connected in series to the grounding transformer at the head and end of the ice-covered lines.The zero-sequence voltage of the distribution networks is regulated by the end CHBC within the permissible range of insulation,and the resulting zero-sequence capacitive current to ground flows through the three-phase ice-covered conductors as ice-melting current,which realizes a better effect than the single-phase short-circuit current ice-melting.By regulating the capacitance current to the ground of the distribution networks through the head CHBC,the size of the ice-melting current can be adjusted arbitrarily.The proposed method does not require a single-phase grounding short circuit and can simultaneously accurately regulate the ice-melting current to melt ice in three-phase lines.CHBCs only have reactive interaction with the distribution networks,saving the capacity of DC sources,and the sum of power interactions is zero,which does not affect the normal supply voltage of the distribution networks,and there is no need for power outages for the entire network loads.The simulation and experimental results verify the feasibility and effectiveness of the proposed method and control scheme.

关 键 词：配电网 三相覆冰线路 级联H桥变流器 零序无功电流 柔性调控 不停电在线融冰 

分 类 号：TM721[电气工程—电力系统及自动化]