【作者】 李军徽；

【导师】 穆钢； 严干贵；

【作者基本信息】 华北电力大学 ， 电力系统及其自动化， 2012， 博士

【摘要】 开发利用大规模再生能源为解决世界性的能源危机与环境污染问题开辟了新途径,对改善能源结构并保证国民经济可持续发展具有重要的战略意义。凤能是目前最具大规模商业化开发潜能的非水能可再生资源,风力发电联网运行是实现风能大规模开发利用的有效途径。但是,风电功率具有的波动性和间歇性对其接入电网带来了显著不利影响,使得大规模风电接入电网的能力受到限制。因此,在保证既有电网安全稳定运行的前提下,如何多接纳风电成为亟需解决的问题。储能系统可以适时吸收释放功率,为平抑风电功率波动、提高风电接入电网的能力提供了有效的手段。目前储能系统成本昂贵,其充放电控制方式可显著影响其使用寿命,所以开展储能系统运行控制策略、容量配置和经济性评价方面的研究工作,具有重要的理论和应用价值。本文首先分析了直驱永磁风电机组的主电路和控制系统的数学模型,构建了包含电池单元、双向斩波电路和并网逆变器的储能系统,根据系统需求设计了主电路参数,采用反馈线性化理论设计了并网变流器的功率解耦控制器,提高了系统运行效率和功率控制效果。分析了单台风电机组-风电场输出功率的波动特性,从时域和频域两个角度对其历史数据进行了统计分析,揭示了风电功率波动特征,为确定风电场储能系统的安装位置、吞吐功率和容量需求以及爬坡率要求奠定了基础。为降低风电功率的随机波动性对电网造成的不利影响,采用了低通滤波算法平滑并网风电场输出有功功率的风储联合运行控制策略。通过对比分析单独采用电池或超级电容器为储能单元的方案的利弊,提出了采用电池-超级电容器混合储能的方案,研究了两者的配比关系及其对平抑效果的影响。最后对比分析了上述三种方案的经济特性。设计了电网低谷时段风电接纳容量算法,提出了在储能系统低谷时刻提高电网接纳风电容量的方法,分析了储能系统的经济效益。综合考虑储能系统的投资成本与经济效益,以储能系统的综合效益最大为目标,提出了一种用于松弛电网调峰能力,提高风电接纳规模的储能系统容量优化配置方法。最后,利用电磁暂态仿真软件PSCAD/EMTDC开发了风储联合运行仿真平台,基于该平台验证了本文提出的并网变流器控制策略的有效性。开发了风储联合运行模拟物理平台,验证了本文提出的风储联合运行控制策略的合理性。更多还原

【Abstract】 The development and utilization of renewable energy has opened new ways to solve the problems of world energy crisis and environmental pollution. Thus, they are strategically important to help upgrade energy structure and ensure sustainable economic development of China. Among non-hydro renewable energy sources, wind energy currently has the greatest potential for large-scale commercial developing. The networking operation of wind power can be an effective way for large-scale development and utilization of wind energy. The characteristics of fluctuation and intermittence of wind power have exerted adverse impacts on the grid and restricted the capacity of wind power integrated into the grid. Therefore, how to accept more wind power while ensuring the safe and stable operation of the existing power grid is a critical problem yet to be solved.The energy storage system can absorb and release power timely. The energy storage system may effectively stabilize the fluctuations of wind power and improve the capacity of wind power integrated into the grid. At present, the cost of energy storage system is quite expensive, and the charge and discharge control mode significantly affects its life. Thus, research on the operation control strategy of energy storage system, capacity allocation and economic evaluation can be substantial both in theories and applications.In this dissertation, the mathematical models of the main circuit and the control system of a direct driving wind permanent magnet generator was analyzed at first. An energy storage system which includes battery units, two-way chopped circuits and grid inverter was constructed. Parameters of the main circuit were determined according to the system’s requirements. To improve the efficiency of the system and the performance of the power control, a power decoupling controller of grid-connected inverter was designed by using the feedback linearization approach.The waveform characteristics of steady power output from a single typhoon electric unit to wind farm were analyzed. To reveal the fluctuating characteristic of wind power, the statistical analysis of its historical data in the time domain and frequency domain was carried out. These analyses have laid foundations for deciding the installation locations of energy storage system and the demands of maximum power, capacity, and climbing rate in a wind farm.To reduce the adverse effects caused by the random fluctuating of wind power, the operating control strategy based on low pass filtering which can smooth wind farm output active power is applied. Through analyzing the advantages and disadvantages of using batteries and super capacitor individually for energy storage, a scheme of hybrid energy storage composed of batteries and super capacitors was presented, and the ratio relations between these batteries and super capacitors and their effects on attenuation were studied. The economic characteristics of these three schemes were compared and analyzed.An algorithm of wind power integration during low load time was presented. An method of using energy storage system to increase the wind power integration during low load time was proposed as well. The economic benefits of energy storage system was investigated. Considering the investment cost and economic benefits of energy storage system, an optimal energy storage capacity allocation method to maximize economic benefits of energy storage systemwas proposed to relax peak load regulation ability and increase wind power integration.A numerical simulation platform for combined operating of wind power-energy storage system was developed based on the electromagnetic transient simulation software PSCAD/EMTDC. The effectiveness of the grid-connected converter control strategy was verified on this platform. A physical simulation platform for combined operating of wind power-energy storage system was also established. The rationality of the combined operating control strategy of wind power-energy storage system was verified on this platform.更多还原