Stability Analysis of VSC MTDC Grids Connected to Multimachine AC Systems
Stability Analysis of VSC MTDC Grids Connected to Multimachine AC Systems
复制标题
DOI：
10.1109/tpwrd.2011.2165735
复制
发表时间：
2011-10-01
影响因子：
4.4
通讯作者：
Pan, Jiuping
中科院分区：
文献类型：
--
作者：
Chaudhuri, Nilanjan Ray;Majumder, Rajat;Pan, Jiuping
本文研究了多机交流系统与多端直流（MTDC）电网之间的相互作用及其对交直流联合系统整体稳定性的影响。基于电压源换流器（VSC）的MTDC电网，这是兼容的标准多机交流系统模型的通用建模框架，开发进行模态分析和瞬态仿真。一个一般的不对称双极转换器配置，包括正，负极转换器和直流电缆网络的正，负，金属回路被认为是使不同类型的故障和直流侧不平衡的研究。详细的动态表示的直流电缆与分布式π-截面模型一起使用沿着平均模型和解耦控制的换流站。在Matlab/SIMULINK中建立的平均模型与EMTDC/PSCAD中建立的详细开关模型进行了比较，验证了模型在小扰动和大扰动下的响应。例如，在一个实施例中，DC侧的故障）。进行模态分析，以确定的性质和根本原因的动态响应。多机交流系统和MTDC电网之间的相互作用检查以下故障的交流和直流侧和中断的转换器。结果表明，在某些情况下，不稳定的原因只能归因于直流侧的状态变量。转换器沿着与直流电缆网络的平均模型被证明是必不可少的，以分析组合AC-MTDC电网的稳定性和动态。
Interaction between multimachine ac systems and a multiterminal dc (MTDC) grid and the impact on the overall stability of the combined ac-MTDC system is studied in this paper. A generic modeling framework for voltage-source converter (VSC)-based MTDC grids, which is compatible with standard multimachine ac system models, is developed to carry out modal analysis and transient simulation. A general asymmetric bipole converter configuration comprising positive and negative pole converters and dc cable network with a positive, negative, and metallic return circuit is considered to enable different types of faults and dc-side unbalance studies. Detailed dynamic representation of the dc cables with distributed pi-section models is used along with the averaged model and decoupled control for the converter stations. An averaged model in Matlab/SIMULINK is validated against the detailed switched model in EMTDC/PSCAD by comparing the responses following small and large disturbances (e. g., faults on the dc side). Modal analysis is performed to identify the nature and root cause of the dynamic responses. Interaction between a multimachine ac system and an MTDC grid is examined following faults on the ac and dc sides and outage of converters. It is shown that the cause of instability in certain cases could only be attributed to the dc-side state variables. An averaged model of the converter along with the dc cable network is shown to be essential to analyze the stability and dynamics of combined ac-MTDC grids.