多因子制约下的MMC-MTDC功率均衡控制策略  

MMC-MTDC Power Balance Control Strategy under Multi-factor Constraints

作　　者：蔡赟 江友华 叶尚兴 胡中鲲 CAI Yun;JIANG Youhua;YE Shangxing;HU Zhongkun(College of Electronics and Information Engineering,Shanghai University of Electric Power,Shanghai 200090;Lishui Power Supply Company,State Grid Zhejiang Electric Power Co.,Ltd.,Lishui 323000;Anqing Power Supply Company,State Grid Anhui Electric Power Co.,Ltd.,Anqing 246000)

机构地区：[1]上海电力大学电子与信息工程学院,上海200090 [2]国网浙江省电力有限公司丽水供电公司,丽水323000 [3]国网安徽省电力有限公司安庆供电公司,安庆246000

出　　处：《电气工程学报》2024年第4期204-214,共11页Journal of Electrical Engineering

基　　金：上海市自然科学基金资助项目(21ZR1424800)。

摘　　要：传统下垂控制无法保证系统受到风场功率波动后不平衡功率的准确分配和直流电压的稳定,需要对产生该问题的原因进行分析并解决。针对此现状,首先通过建立换流站的数学模型,分析风场功率波动对下垂特性的影响。然后通过多端柔性直流输电等效电路模型,分析线路阻抗对电压波动的影响,并引入功率分配权值系数以稳定直流电压。同时考虑不同风速波动场景下换流站的实时功率裕度,避免换流站满载。基于以上分析,提出一种改进的自适应下垂控制策略,能自适应修正下垂曲线系数,使得换流站在保证电压稳定的前提下将U-P特性曲线向最优功率分配逼近。最后,在PSCAD上搭建了包含风电场在内的三端MMC-MTDC系统模型,仿真结果表明改进下垂控制策略的有效性。The traditional droop control cannot ensure the accurate distribution of the unbalance power and the stability of the DC voltage after the wind field power fluctuation.The causes of this problem need to be analyzed and solved.In view of this situation,the influence of wind power fluctuation on droop characteristics is analyzed by establishing a mathematical model of the converter station.Then,through the equivalent circuit model of multi-terminal flexible DC transmission,the influence of line impedance on voltage fluctuation is analyzed,and the power distribution weight coefficient is introduced to stabilize the DC voltage.The real-time power margin of the converter station under different wind speed fluctuation scenarios is also considered to avoid full load of the converter station.Based on the above analysis,an improved adaptive droop control strategy is proposed,which can adaptively modify the droop curve coefficient,so that the converter station can approximate the U-P characteristic curve to the optimal power allocation under the premise of ensuring voltage stability.Finally,a three-terminal MMC-MTDC system model including a wind farm is built on the PSCAD,and the simulation results show the effectiveness of the improved droop control strategy.

关 键 词：多端柔性直流输电 线路电阻 功率裕度 有功功率优化分配 改进下垂控制 

分 类 号：TM464[电气工程—电器]