基于多电平变流器模块的直流输电系统控制  

The DC Transmission System Control Based on the Multilevel Converter Module

作　　者：刘威[1] 于飞 董霜[1] 沙志成[1] 李可军[2] LIU Wei;YU Fei;DONG Shuang;SHA Zhicheng;LI Kejun(Shandong Electric Power Engineering Consulting Institute Co.,Ltd.,Jinan 250013,Shandong,China;School of Electrical Engineering,Shandong University,Jinan 250061,Shandong,China)

机构地区：[1]山东电力工程咨询院有限公司,山东济南250013 [2]山东大学电气工程学院,山东济南250061

出　　处：《电网与清洁能源》2024年第9期47-53,共7页Power System and Clean Energy

基　　金：国家自然科学基金项目(51777116)。

摘　　要：为了保证直流输电系统在发生三相短路故障时输电电压的稳定性,有效控制输电系统的运行,该文提出了基于多电平变流器模块(modular multilevel converter,MMC)的直流输电系统运行控制方法。利用反并联二极管与并联电容来设计多电平变流器模块,获得交流等效电感,保证换流站交直流量与有功功率相同,明确换流站内功率情况;将该模块与前馈解耦补偿项相结合,运用PI获得电流内环运行控制器的输入值,实现电流解耦,增强直流电压的稳定控制,提高输电系统抗扰动性能;通过修正与控制环节获得对应参考值,以及最佳运行控制结果。通过实验表明:设计的模块既能保证输电系统在正常工作状态下平稳运行,也能在发生故障时将影响控制在安全范围内,保证电力系统输电稳定。To ensure the stability of the transmission voltage and effectively control the operation of the DC transmission system in the event of three-phase short circuit fault,this paper proposes a DC transmission system operation control method based on the multilevel converter module(MMC).The multilevel converter module is designed by using the anti parallel diode and parallel capacitor to obtain the AC equivalent inductance to ensure that the AC/DC flow of the converter station is the same as the active power,and clarify the power situation inside the converter station.The module is combined with the feedforward decoupling compensation term,and the PI is used to obtain the input value of the current inner loop operation controller to realize current decoupling,and increase the stability control of DC voltage,and improve the anti-interference of the transmission system.The corresponding reference value is obtained through the correction and control link,and the optimal operation control result is obtained.The experiment proves that the designed module can ensure the smooth operation of the power transmission system under normal working conditions,control the impact in a safe range when a fault occurs,and ensure the stability of the power transmission system.

关 键 词：系统运行控制 PI控制器 直流输电系统 有功功率 模块化多电平变流器 MMC 

分 类 号：TM721.1[电气工程—电力系统及自动化]