【作者】 杜振华；

【导师】 马晓春；

【作者基本信息】 北京交通大学 ， 电气工程， 2012， 硕士

【摘要】 气候变化和能源供给已越来越引起人们的关注,世界范围内风力发电已成为电力系统一个重要来源。随着风力发电装机容量的不断扩大,风力发电机与局部电网之间的相互影响也越来越大,为了维持电网的稳定,电网导则要求风机必须具有故障穿越(Fault Ride Through, FRT)的能力。永磁直驱风力发电系统因省去了传动齿轮箱,抑制了噪声,降低了维护成本,系统效率和运行可靠性高等诸多优点而备受关注。本文主要研究“不可控整流+三重Boost+两重逆变”型永磁直驱风力发电系统的单机建模和故障穿越技术。阐述了风电标准对故障穿越能力的要求和风力发电机组的基本工作原理。详细分析了永磁直驱风力发电系统的结构及其控制策略,并在电力系统仿真分析软件PSCAD/EMTDC中搭建了整个系统的仿真模型。仿真的结果与理论分析相一致,验证了本文所搭建模型以及系统控制策略的正确性,为进一步研究提供了平台基础。针对并网变压器高压侧电网电压出现三相对称跌落、不对称跌落以及骤升三种故障情况,分别分析了故障时永磁直驱风力发电系统响应特性,并针对各类故障所引起的问题,给出解决方案措施,并在建立的模型中对所提方案进行了仿真验证,仿真结果验证了各方案中控制策略的有效性。在电网故障期间,各方案能够实现机组并网运行,提高永磁直驱风力发电系统故障穿越运行能力,即机组实现了故障穿越。更多还原

【Abstract】 There is growing concern about climate change and energy supply issues. Wind energy has been noted as the most rapidly growing technology in renewable power generation and wind power generation has become an important source of power systems. With the increase of wind farms installed capacity, there is growing interaction between wind power generation and local power network. In order to maintain the stability of the power grid, now grid codes require that wind farms have to fulfill demanding fault ride through (FRT). The type of direct driven permanent magnet synchronous generators (PMSG) has the capability of direct connection with no gearbox, and it has many advantages, such as:low noise, low maintenance costs, etc. The topology structure of un-controlled rectifier+three-cell interleaving parallel boost+two-cell interleaving parallel PWM inverter in the direct drive wind power and its fault ride through technology has been researched in this thesis.Fault ride through capability requirements and wind turbines basic working principle have been detailed studied. The topology structure and its control strategy of wind power has been analyzed, the whole system simulation model has been build up based on the PSCAD/EMTDC software. Simulation results are in good agreement with theoretical analysis, which verify the system model and its control strategy are correct and feasible. And it provides a platform foundation for further research.The dynamic behaviors of PMSG during symmetrical three phase voltage sags, unsymmetrical voltage sags and symmetrical three phase voltage swells have been separately analyzed. According to various types of problems that caused by grid faults, this thesis presents control strategy to solve the problems. The control strategy of solution measures have been demonstrated using PSCAD/EMTDC based simulation.The solution measures presented in this thesis is that control strategy is suitable for voltage faults transient period while grid integration. Simulation results show that the proposed control strategy is effectiveness and efficiency. As a result, the proposed method can effectively improve the direct-driven wind power system FRT capability, that is variable speed wind turbine unit with a PMSG realizes fault ride through.更多还原