含UPFC电力系统潮流优化及预防控制研究

发布时间：2019-04-24 12:02

【摘要】：统一潮流控制器(UPFC)作为一种功能强大的FACTS器件,具有多种控制模式,能够对线路潮流、阻抗和母线电压进行灵活的调节与控制,近些年得到了广泛的关注。然而,当UPFC被设置在不合理的控制模式和控制目标时,UPFC的控制作用将可能给系统的静态安全带来隐患。因此,为了充分发挥UPFC的控制作用,挖掘现有电网输电潜力,提高系统的静态安全性,实现系统经济安全运行,需要对含UPFC的电力系统的潮流优化和静态安全预防控制进行研究。本文针对以上问题展开了如下相关研究:(1)研究了 UPFC的选址和含UPFC电力系统的潮流优化问题。由于UPFC的安装位置直接影响着UPFC潮流调节能力,本文首先基于的UPFC直流潮流功率注入模型,提出了一种简便有效的UPFC选址方法,并在IEEE30测试系统中确定了 UPFC的安装位置。然后,以提高系统运行经济性为目标,建立含UPFC的潮流优化模型,采用粒子群算法求解,并比较了 UPFC安装前后系统网络损耗情况。计算表明,优化后的系统网络损耗和运行费用得到明显降低,同时UPFC对降低系统网损具有一定的帮助。(2)提出了一种考虑UPFC控制模式的潮流计算方法,并基于该方法分析了 UPFC的控制模式对系统的静态安全性的影响。UPFC具有定功率控制、相角调节控制、电压调节控制和阻抗补偿控制四种常见的控制模式,通过分析以上控制模式的控制特性,建立了 UPFC各个控制模式下的潮流计算方法。在此基础上,通过计算UPFC采用各种控制模式下系统发生N-1故障时的潮流分布,分析了 UPFC控制模式对系统静态安全的影响。计算结果表明UPFC的控制模式对系统潮流具有较大影响,选择合适的控制模式,将对系统的静态安全性提高具有一定的帮助。(3)提出了一种考虑UPFC控制模式的UPFC静态安全预防控制方法,并进一步在含UPFC系统潮流优化中考虑静态安全预防控制,综合优化系统的经济性和静态安全性。为了提高系统的静态安全性,以正常状态下系统过载情况、N-1后系统过载情况以及系统静态安全裕度三级评价指标构成最后的目标函数,在UPFC运行参数的优化模型中增加加N-1静态安全约束和UPFC控制模式的选择,形成UPFC静态安全预防控制方法;然后,将电力系统的潮流优化与N-1预防控制相结合,构造综合反映系统的经济性和安全性目标函数,并考虑N-1静态安全约束以及UPFC控制模式的选择,建立优化模型,计算表明优化后的系统参数、UPFC控制参数以及控制模式,能够有效的改善系统的经济性和静态安全水平。
[Abstract]:As a powerful FACTS device, the unified power flow controller (UPFC) has many control modes. It can adjust and control line power flow, impedance and bus voltage flexibly, and has been paid more and more attention in recent years. However, when UPFC is set in unreasonable control mode and control target, the control effect of UPFC may bring hidden trouble to the static security of the system. Therefore, in order to give full play to the control role of UPFC, tap the transmission potential of the existing power grid, improve the static security of the system, and realize the economic and safe operation of the system, It is necessary to study the power flow optimization and static security prevention and control of power system with UPFC. The main contents of this paper are as follows: (1) the location of UPFC and power flow optimization of power system with UPFC are studied. Because the installation position of UPFC directly affects the ability of UPFC power flow regulation, this paper presents a simple and effective UPFC location method based on the UPFC DC power flow power injection model, and determines the installation location of UPFC in the IEEE30 test system. Then, in order to improve the economic performance of the system, a power flow optimization model with UPFC is established and solved by particle swarm optimization (PSO) algorithm, and the network losses of the system before and after installation of UPFC are compared. The calculation shows that the network loss and operation cost of the optimized system are obviously reduced, and the UPFC is helpful to reduce the network loss of the system. (2) A power flow calculation method considering the UPFC control mode is proposed. Based on this method, the influence of the control mode of UPFC on the static security of the system is analyzed. It has four common control modes: constant power control, phase angle control, voltage regulation control and impedance compensation control. By analyzing the control characteristics of the above control modes, the power flow calculation methods under each control mode of UPFC are established. On the basis of this, the influence of UPFC control mode on the static security of the system is analyzed by calculating the power flow distribution of the system under various control modes. The calculation results show that the control mode of UPFC has a great influence on the power flow of the system, and the appropriate control mode is selected. It will be helpful to improve the static security of the system. (3) A UPFC static safety prevention and control method considering UPFC control mode is proposed, and the static safety preventive control is further considered in the power flow optimization of the system with UPFC. Comprehensive optimization of the economy and static security of the system. In order to improve the static security of the system, the final objective function is composed of the overload condition of the system under the normal state, the overload condition of the system after N ~ (1) and the three-level evaluation index of the static safety margin of the system. The static security control method of UPFC is formed by adding the static security constraint and the selection of UPFC control mode in the optimization model of UPFC operation parameters. Then, combining the power flow optimization with the prevention and control of the power system, the optimization model is established, which reflects the economic and security objective functions of the system, and considers the static security constraints of the power system and the choice of the UPFC control mode. The calculation shows that the optimized system parameters, UPFC control parameters and control mode can effectively improve the economy and static safety level of the system.
【学位授予单位】：东南大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM744

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