交直流配电网柔性多状态开关电压自适应控制策略  

Adaptive Voltage Control Strategy for Soft Normally Open Point in AC/DC Distribution Network

作　　者：窦晓波[1] 皇甫霄文 全相军[1] 胡秦然 肖小龙 吴在军[1] DOU Xiaobo;HUANGFU Xiaowen;QUAN Xiangjun;HU Qinran;XIAO Xiaolong;WU Zaijun(School of Electrical Engineering,Southeast University,Nanjing 210096,China;Jiangsu Power Testing Research Institute Co.Ltd.,Nanjing 211103,China)

机构地区：[1]东南大学电气工程学院,江苏省南京市210096 [2]江苏省电力试验研究院有限公司,江苏省南京市211103

出　　处：《电力系统自动化》2021年第8期68-76,共9页Automation of Electric Power Systems

基　　金：国家重点研发计划资助项目(2018YFB0904700);国家自然科学基金资助项目(51777031)。

摘　　要：交直流配电网中受端弱交流配电网电压调节能力较弱,需要直流配电网提供功率支撑,而直流配电网受到自身和交流配电网的双重影响,导致直流电压偏差较大且低惯性特征更加明显。对此,文中引入柔性多状态开关(SNOP),并提出一种交直流电压自适应控制策略。首先,分析交流电网电压扰动对直流电压动态响应和惯性调节过程的影响机理,通过设计电压前馈控制方法有效抑制了扰动作用。其次,针对弱交流配电网调节能力不足的问题,设计自适应功率补偿控制方法,使得SNOP能够根据工作点处电压变化量自适应地补偿功率缺额,同时分析了该功率需求对于直流电压偏差的影响;在此基础上针对直流系统,综合考虑直流电压偏差与电压变化率设计了改进的自适应虚拟惯性控制方法,并分析主要控制参数变化对直流系统稳定性的影响,提升了直流系统惯性。最后,在MATLAB/Simulink中搭建交直流混合配电网仿真模型,验证了控制策略的有效性。In AC/DC hybrid distribution networks,the DC distribution network needs to provide power support due to the weak voltage regulation capability of AC weak distribution network at receving end.The DC distribution network is both affected by itself and the AC distribution network,resulting in large deviation of DC voltage and low inertia characteristics more obvious.In light of this,a DC adaptive voltage control strategy considering soft normally open points(SNOPs)is proposed in this paper.Firstly,the influence principle of voltage disturbance in the AC power grid on the dynamic response and inertia regulation process of DC voltage is analyzed,and the disturbance can be effectively suppressed by designing the voltage feedforward control method.Then,aiming at the problem of insufficient regulation capacity of weak AC distribution networks,an adaptive power compensation control method is introduced,which makes SNOP adaptively compensate power shortage according to the voltage variation at the operation point.Meanwhile,the influence of the power demand on the DC voltage deviation is analyzed.On this basis,for the DC system,an improved adaptive virtual inertia control method is devised by comprehensively considering the DC voltage deviation and the voltage change rate,and the influence of main control parameters on the DC system stability is also discussed,which improves the inertia of the DC system.Finally,a simulation model of AC/DC hybrid distribution network is built in MATLAB/Simulink,and the validity of the control strategy is verified.

关 键 词：柔性多状态开关 交直流混合配电网 电压自适应控制 电压扰动 虚拟惯性控制 功率补偿 

分 类 号：TM721.3[电气工程—电力系统及自动化]