【作者】 庞敏；

【导师】 龙军；

【作者基本信息】 广西大学 ， 电力系统及其自动化， 2008， 硕士

【摘要】 最近三十年来,世界各国的电力系统普遍进入大电网,高电压,大机组时代,巨量的电能需要通过长距离的高压输电线送到负荷中心,电力系统受到的压力越来越大,很多系统都运行在其稳定极限附近。与此同时,世界上一些大电网相继发生了一系列由电压失稳导致的停电事故。这些事故停电时间长,波及范围广,损失严重,引起人们对电压稳定问题的严重关注。静止同步补偿器(Static Synchronous Compensator,STATCOM)作为FACTS家族一员,具有快速灵活的无功功率控制能力,它对防止系统电压失稳具有重要的意义,在电压稳定研究中得到越来越多的重视。提供一些指标去评估STATCOM对电力系统电压稳定性影响的效果,去有效反映有STATCOM补偿的系统距离电压失稳点的距离还有多远,正是电力系统的安全运行所迫切需要的。本文从STATCOM的原理图出发,详细阐明了用微分代数DAE方程组代表的STATCOM暂态模型和用于潮流计算的静态模型。基于已阐明的STATCOM的模型,评估STATCOM安装后电压稳定的改善情况,以及STATCOM不同的安装地点对电压稳定造成的影响。文中使用了基于连续潮流法的电压稳定裕度指标VSM,电压崩溃邻近指标VCPI,灵敏度指标,基于特征结构分析法的指标,去评估STATCOM对电力系统电压稳定性影响的效果,以及有效反映有STATCOM补偿的系统距离电压失稳点的距离还有多远。本文分别用四种指标和STATCOM模型在WSCC-3机9节点测试系统上进行了大量的数值计算和分析。结果表明,在相应的负荷节点安装STATCOM后的电压稳定性的各项指标均比相应的负荷节点未安装STATCOM的相应指标有较大改善。充分证明了STATCOM对于电压稳定性提高的有效性。基于连续潮流法的电压稳定裕度指标VSM是本文提出的新指标,可以评估不同的STATCOM安装地点,不同的STATCOM容量对电压稳定的改善程度。更多还原

【Abstract】 The power systems in the world generally have got into the age with the character of great network, high voltages and large capacity generators for last 30 years. Since the reality that a number of power must be transmitted to the distant centers of load with the high voltage lines, the stress on the power systems become heavier and heavier, so that the power systems runs on the edge of stability limit. In the meantime, a series of blackout which were derived by voltage instability, happen in some great networks around the world. These accidents brought a long time blackout with the character of expanding widely and great loss, for this reason, the problem of voltage stability become the focus in the people’s eyes.As a member of FACTS family, STATCOM with the capacity of flexible absorbing or generating reactive power is significant for preventing voltage instability, so that STATCOM is paid attention to more and more in the study of voltage stability. It is necessary for the safety of power systems to assess the effect of STATCOM about voltage stability, and reflect the distance with the voltage collapse point.In this thesis, the differential algebraic equation (DAE) set were reduced to represent the transient stability model and steady state model with beginning from the principle scheme of STATCOM.On the base of STATCOM which were reduced, voltage stability index(VSM) reduced from continuation power flow, VCPI, sensitivity index, eigenvalue structure analysis were used to evaluate the effect of STATCOM about voltage stability, and reflect the distance with the voltage collapse point in the method of comparing with or without STATCOM in the bus or installing the STATCOM in the different buses.On the test case of WSCC 3 machines 9 buses, a number of calculation and analysis were performed using these four indices and STATCOM models. It is concluded that the effect of voltage stability indices were improved distinctly in the allocation with STATCOM in the buses than the allocation without STATCOM. It is proved that STATCOM can effectually improve voltage stability of power system. Voltage stability index(VSM) reduced from continuation power flow, is a new index claimed in this thesis. VSM can assess the different effect when STATCOM of different capacity installed in different buses.更多还原