虚拟同步机电流受限暂态电压支撑机理与改进故障穿越控制研究
Current-constrained Transient Voltage Response Analysis and an Improved Fault-ride Through Control of the Virtual Synchronous Generator
张宇 1张琛 1蔡旭 1余勇铮 2梁李柳元2
作者信息
- 1. 电力传输与功率变换控制教育部重点实验室(上海交通大学电气工程系),上海市 闵行区 200240
- 2. 宁德时代新能源科技股份有限公司,福建省 宁德市 352100
- 折叠
摘要
针对虚拟同步机在电网低、过电压故障下所面临的无功电压支撑不足、特性差等问题,建立考虑电流限幅特性的虚拟同步机等效电路模型,并基于拓扑同伦原理,给出不同无功电压控制在等效电路相量图上的几何表征方法.利用该方法,揭示几种常见无功电压控制下的虚拟同步机电流受限暂态电压支撑机理,并由此提出一种改进的故障穿越控制策略,有效改善电网低电压、过电压故障下的暂态电压控制能力和支撑特性,进而缓解故障期间的暂态功角稳定问题.基于PSCAD/EMTDC仿真对所提机理和故障穿越控制方法进行详细验证,最后,在3 机 9节点系统中对其在近、远区电网故障下的支撑特性进行仿真验证.
Abstract
To address the problems of insufficient reactive voltage support and poor characteristics faced by virtual synchronous generator(VSG)under low/over-voltage faults,this paper proposes an equivalent circuit model of virtual synchronous machines considering the current limitation,and the geometric characterization method regarding several reactive power and voltage controls on the phase diagram of the equivalent circuit is given based on the topological homotopy method.By leveraging the proposed method,the current-constrained transient voltage supporting mechanism of the VSG under several common Q/U controls is revealed,and an improved fault ride-through(FRT)control method is proposed,which effectively improves the transient voltage supporting performance of the VSG under low/over-voltage faults of the grid as well as the power angle stability during the fault ride-through process.The mechanism revealed in this paper and the proposed FRT control method are verified via PSCAD/EMTDC simulation.Finally,the performance of the proposed FRT control method is also verified in a three-machine-nine-bus system subjected to short circuit faults occurring in both near and far zones.
关键词
并网变换器/构网型控制/故障穿越/电流限幅/电压支撑控制/暂态同步稳定性Key words
voltage source converter/grid-forming control/fault ride through/current limitation/voltage supporting control/transient synchronization stability引用本文复制引用
基金项目
国家自然科学基金项目(52207215)
宁德时代科技项目(CT-RCCCGESA01)
出版年
2024
国家科技期刊平台
NSTL
万方数据