基于相位跳变补偿的虚拟同步发电机低电压穿越控制策略研究  

Research on Low Voltage Ride-through Control Strategy of Virtual Synchronous Generator Based on Phase Jump Compensation

作　　者：郑涛 王子鸣 邹芃蓥 ZHENG Tao;WANG Ziming;ZOU Pengying(State Key Laboratory of Alternate Electrical Power System With Renewable Energy Sources(North China Electric Power University),Changping District,Beijing 102206,China)

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学),北京市昌平区102206

出　　处：《电网技术》2023年第1期100-108,共9页Power System Technology

基　　金：国家自然科学基金联合基金项目(批准号:U2166205)。

摘　　要：虚拟同步发电机(virtual synchronous generator,VSG)作为构网型(grid-forming,GFM)逆变器控制技术之一,在提升电网的惯量、支撑电压等方面发挥巨大作用,但目前针对VSG短路故障的低电压穿越(简称“低穿”)控制策略的研究亟需进一步完善。在电力系统中,短路故障的发生与切除均会导致电网的拓扑结构随之改变,进而造成VSG并网点电压幅值与相位跳变。针对这一问题,该文分析了故障时幅值、相位跳变对常规低穿控制策略的影响,提出一种基于幅值切换与相位补偿的VSG改进低穿策略。该策略分别从幅值与相位两个角度对逆变器端口电压进行调控,能够实现低穿期间的过流抑制及功率输出的快速稳定。此外,该文针对故障恢复时同样存在并网点电压相位跳变问题,为抑制此时电压跳变对逆变器造成的过流冲击等问题,分析了VSG改进低穿策略在故障恢复期间的适用性;在此基础之上,进一步利用辅助控制实现低穿控制策略的平滑退出,恢复VSG正常控制状态。最后,利用MATLAB/Simulink仿真验证所提策略的有效性。As one of the grid-forming(GFM) inverter control technologies, the virtual synchronous generator(VSG)plays a huge role in improving the inertia and supporting the voltage of the power grid. The research on the low-voltage ride-through control strategy urgently needs further improving.In the power system, the occurrence and removal of the short-circuit faults may lead to changes in the topology of the power grid, resulting in the voltage amplitude and phase jumps at the VSG grid-connected points. Aiming at this problem, this paper analyzes the influence of the amplitude and phase jumps on the conventional low-penetration control strategies during the faults, and proposes a VSG improved low-penetration strategy based on the amplitude switching and phase compensation. This strategy regulates the inverter port voltage from two perspectives of the amplitude and the phase, which realizes the overcurrent suppression during the low breakdown period and the fast stabilization of the power output. In addition, this paper finds that there is also the problem of voltage phase jumps at the grid connection points during the fault recovery. In order to suppress the overcurrent impact of the inverter caused by the voltage jumps at this time, this paper analyzes the application of the improved VSG low-piercing strategy during the fault recovery period. On this basis, the auxiliary control is further used to realize the smooth exiting of the low penetration control strategy, restoring the normal control state of the VSG. Finally, the effectiveness of the proposed strategy is verified by using the MATLAB/Simulink simulation.

关 键 词：虚拟同步发电机 低电压穿越 相位跳变 故障限流 故障恢复 

分 类 号：TM721[电气工程—电力系统及自动化]