新能源发电并网变流器故障穿越能力的多时间尺度评估方法研究

项目名称： 新能源发电并网变流器故障穿越能力的多时间尺度评估方法研究

项目编号： No.51507118

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 电工技术

项目作者： 黄萌

作者单位： 武汉大学

项目金额： 21万元

中文摘要： 在新能源并网发电系统的应用中，电力电子并网变流器对电网故障和扰动敏感，其运行行为影响并网导则中故障穿越要求的实现，现有变流器设计中通常未考虑其对故障冲击过程的耐受程度。为此，本申请面向并网变流器在故障和扰动下的运行问题，研究并网变流器安全分析和评估方法。首先，项目分析并网变流器在电网故障和扰动下动态响应的机理，识别变流器运行的多时间尺度非线性特征，揭示变流器安全性特征。其次，建立并网变流器时间尺度分解下的微分-代数方程组，基于非线性分岔分析提出在关键参数空间中的变流器运行安全域。最后，提出运行安全域变化的惩罚因子，采用奇异摄动模型方法，评估变流器的故障穿越能力。本申请将完善并网变流器非线性运行特性的研究，从变流器自身耐受冲击能力出发建立实用化的变流器设计评估体系，为新能源发电安全稳定并网发电提供技术支撑。

中文关键词： 并网变流器；非线性动力学；电网故障；多时间尺度；评估方法

英文摘要： In new energy power generation system, power electronic grid-connected converters are sensitive to grid faults and disturbance, but present power converter design is usually not considering the fault ride-through capability of the converter and the behavior during the transient. Therefore, this proposal is facing the problem of the complex behavior of grid-connected converters during the fault and disturbance, researching the evaluation method for it. Firstly, the multi-time-scale transient response of grid-connected converters due to the fault and disturbance will be analyzed, the security of the converters is described. Then, the differential algebraic equation model of the converter system will be derived by multi-time-scale decomposing. The constraints of the model will be given in critical parameter space by nonlinear bifurcation analysis. Finally, the penalty factor will be derived to evaluate the fault ride-through capability by singular perturbation method. This research will enrich the nonlinear dynamic research of grid-connected converters and establish a practical evaluating method for grid-connected converter fault ride-through capability. This will give strong support for the security of new energy power generation system.

英文关键词： Grid-Connected Converter;Nonlinear Dynamics;Grid Fault;Multi-Time-Scale;Evaluation Method