【作者】 周金辉；

【导师】 余贻鑫；

【作者基本信息】 天津大学 ， 电力系统及其自动化， 2012， 博士

【摘要】 在我国开发利用风能等可再生能源,不仅有利于优化能源结构、保护环境,而且还会提高我国能源供应的多样性和安全性,是我国实现电力可持续发展的必然选择。按照国家“建设大基地、融入大电网”的风电发展战略,目前我国风电已进入大规模基地式集中开发阶段。然而,由于风电本身所固有的特殊性,给电力系统的规划和运行带来了很大的挑战,为此,本文对于大规模风电并网后的电力系统规划(即电力规划)问题进行了研究。首先,提出了大规模风电接入后的输电网综合扩展规划方法。该法考虑了风电出力的波动性对输电网有功潮流与无功潮流的影响,实现有功规划与无功规划的整体优化。为应对问题求解计算上的复杂性,提出了启发式的优化算法。先将原问题分解为两个子问题:网络设备投资决策与方案的控制成本评估,然后经由原问题的规划目标进行总体协调。在此基础上,算法充分挖掘目标函数与问题本身的特性,优化过程物理意义清晰,易于理解,明显地提高了计算速度,能在工程可接受的计算时间内获得较优的规划方案。其次,立足于全社会成本视角,构建了含大规模风电的电力规划方案价值评估框架与评估方法。考虑到风电出力的波动性,在计及静态和动态安全约束的经济调度模型基础上,结合机组组合优化模型与校正性控制模型,实现了系统运行过程的详细模拟。最终获得全年每小时的燃料、环境和网损成本,再结合电源的容量成本、电网成本及系统的可靠性成本,从而实现了规划方案的全社会成本评估。最后,通过示例验证了在评估含大规模风电的电力规划方案时,详细模拟系统运行的重要意义和所提方法的有效性。最后,针对常规(不含风电)输电网规划,在目标函数中引入静态安全风险费用,将其与网络设备(线路与无功补偿装置)投资的年值费用、年运行费用综合衡量,计及预想事故的发生概率和交流潮流约束,建立了计及静态安全风险的输电网短期综合扩展规划的数学模型,进行优化规划,所得方案可以实现投资与风险之间的最佳平衡。在静态安全风险评估中,采用基于有功静态安全域和电压灵敏度循环迭代的方法解决了基于交流潮流模型进行负荷削减优化的难题。模型通过两阶段的寻优算法进行求解,该法不仅降低了原问题的求解难度,而且最终可获得若干数目的满意解。更多还原

【Abstract】 The development and utilization of renewable energy sources such as wind energy in China, this is very helpful not only to optimize energy structure and improve environment, but also to enhance our energy supply diversity and security. So that is a nesessary choice for sustainable development of electric power industry in China. According to the national strategy on wind power development“building large bases, integration into bulk power grid”, the wind power base development in China is initiated at present. However, due to inhenrent characteristics of wind power output, that brings great challgenes to powet system planning and operation. Based on this, power planning when large-scale wind power is integrated into the power system is studied in the dissertation.Firstly, the integrated expansion planning approach for transmission network with large-scale wind power is proposed. The impacts of variability for wind power ouput on active power flows and reactive power flows for transmission network are considered in the approach, and the whole optimization of active planning and reactive planning could be realized. To cope with the computing complexity, the heuristic optimization algorithm is presented. At first, the original problem is divided into two sub-problems: investment decisions of power network equipments and the cost evaluation for remedial controls of an alternative. Then comprehensive coordination between the sub-problems is achived by planning objective. Based on this, the characteristics of planning objective and the problem itself are analyzed, and then the optimization strategy is designed. The proposed algorithm is easy to understand and the physical meaning is clear, moreover it could reduce computation burden significantly, and is able to get superior planning alternatives in the acceptable time for engineering practice.Secondly, the framework of evaluation for power system planning with large-scale wind farms is established from the perspective of the total social cost. Aiming at the framework, the improved value evaluation method is proposed. Considering the variability of wind power is considered, daily-ahead (or week-ahead) unit commitment model, steady state and dynamic secutiy constrains based economic dispatch model and remedial control model are included in the simulation process. The raised method implements detailed simulation for system operation process. Hence the hourly fuel, environmental and network loss cost in the year for the given planning alternative could be calculated. These costs are to be combined with generation capacity cost, power network cost and system reliability cost, so that the total social cost of the alternative can be determined. Finally the importance of detailed operation simulation and the effectiveness of the method are verified by means of case studied.Finally, for conventional transmission expansion planning (without wind power), the mathematical model for the short term integrated expansion planning of real and reactive power for transmission network was formulated, and the sum of cost of the lines, reactive power compensation, operation cost and risk cost were considered as an objective function, the probability of contingency and AC power flow constraint were included in the model. The best alternative obtained by solving the planning model could reach the balance between investment and risk. For purpose of achieving the static security risk assessment based on the AC model, the two-stage approach for load curtailments based on active power steady-state security region and voltage sensitivity iteratively was proposed. To deal with the computing complexity of solving the model presented, the two-step optimization algorithm was provided, which not only could reduce the difficulty of the problem, but also some satisfactory solutions could be identified to support planners in decision making.更多还原