System Frequency Support Through Multi-Terminal DC (MTDC) Grids
System Frequency Support Through Multi-Terminal DC (MTDC) Grids
复制标题
DOI：
10.1109/pesmg.2013.6672383
复制
发表时间：
2013-02
影响因子：
6.6
通讯作者：
N. Chaudhuri;R. Majumder;B. Chaudhuri
中科院分区：
文献类型：
--
作者：
N. Chaudhuri;R. Majumder;B. Chaudhuri
控制多端直流（MTDC）电网中的换流站为周围的交流系统提供频率支持是本文的主题。每个转换器的标准自主功率共享控制回路被修改为具有频率下垂控制回路。目标是最小化与标称AC系统频率的偏差，并在MTDC电网的换流站之间分担频率支持的负担。频率支持的有效性证明通过非线性仿真的测试系统，由三个隔离的交流系统通过MTDC电网与四个换流站互连。建立了多机交流-多机直流组合系统的平均模型，并对该系统进行了模态分析。模态分析用于表征和证实频率下垂控制存在下的时域行为。已经确定，如果系统特征值对控制参数（例如，下垂系数）通过模态分析被先验地考虑。
Control of the converter stations in a multi-terminal DC (MTDC) grid to provide frequency support for the surrounding AC systems is the subject matter of this paper. The standard autonomous power sharing control loop for each converter is modified with a frequency droop control loop. The objective is to minimize the deviation from nominal AC system frequency and share the burden of frequency support among the converter stations of the MTDC grid. The effectiveness of the frequency support is demonstrated through nonlinear simulation of a test system consisting of three isolated AC systems interconnected through an MTDC grid with four converter stations. An averaged model of the MTDC grids is developed to carry out modal analysis of combined multi-machine AC-MTDC systems. Modal analysis is used to characterize and substantiate the time domain behavior in presence of frequency droop control. It is established that appropriate droop control loop for the MTDC grid converters could be effective in reducing the deviation from nominal AC system frequency provided the sensitivity of the system eigen-values to changes in control parameters (e.g., droop coefficients) is accounted for a priori through modal analysis.