可控串补晶闸管失控引起的振荡现象机理研究

根据可控串补的时域稳态特性,分析了可控串补在感性调节模式下的两种具体情况,定义了可控串补的正常感性调节模式和深度感性调节模式,分别研究了这两种模式下的振荡现象,指出这些振荡是由于晶闸管失控而产生,并推导了可控串补发生振荡的临界条件。根据不同需求提出了几种电抗值选择原则,对TCSC的规划设计有一定的指导意义。     

Mitigation of the impact of transformer inrush current on voltage sag by TCSC

Thyristor Controlled Series Capacitor (TCSC) as a dynamic system, besides its capability in increasing power transfer in transmission lines, can be used to enhance different power system issues. In this paper, the effect of TCSC on voltage sag following transformer inrush current is investigated. It is shown that excessive transient inrush current occurring during transformer energizing can be mitigated by TCSC. Hence, voltage sag as one of the key components of the power quality is alleviated for the sensitive loads that are connected to the same bus which the power transformer is energized from. During a fault, TCSC can improve the voltage sag by limiting the current and help to keep the voltage as high as possible. Moreover, the inrush currents and the associated voltage sags that usually occur after clearing heavy single- or multistage faults are mitigated by the presence of TCSC. The model used for simulating inrush current is based on the characteristics of the major hysteresis loop out of which the internal trajectories are defined using the translation principal and a linear compensation to generate closed loops. An arctangent relation between the flux and the exciting current is defined. The expression parameters are deduced by curve fitting empirical data defining the major loop or the single-valued saturation characteristic.     

TCSC在次同步谐振中的借阻尼现象

采用了基于时域仿真的复转矩系数法研究电力系统的电气阻尼特性。在IEEE次同步谐振第一标准模型的基础上,分别将其25%,50%,100%容量的固定串补替换为TCSC后进行仿真分析。分析结果表明,在串补度相同的情况下,系统总阻尼近似守恒,TCSC基本不提供正阻尼,但TCSC由于其高度非线性,使系统不同频率间发生了能量交互,从而增加了某些频率的阻尼,同时也降低了另外一些频率处的阻尼,出现了借阻尼现象。讨论了借阻尼现象对SSR的正反两方面影响,并利用仿真实验验证了TCSC抑制和引起SSR的可能性。该现象的发现对T     

基于不同控制策略的微网仿真

考虑微网系统建设成本和运行的灵活性、可靠性,对微网建设初期的接线方案进行了选择.研究了2种微源控制方法,基于微源的不同控制原理建立了微网系统仿真模型,针对计划孤网和非计划孤网中的下垂控制和混合控制进行了仿真分析.仿真结果验证了微网计划孤网的稳定性和孤网控制方法的有效性.任何控制方式下微网再并网时,均需对各微源出力进行重新调整,才能保证微网运行模式的平滑过渡.     

Impact of FACTS devices on exercising market power in deregulated electricity market

In power system studies, congestion in transmission lines and utilization of flexible alternating current transmission system (FACTS) devices are closely associated. These devices are very important due to their role in power delivery system enhancement. It is to be noted that the generation companies can exercise their market power which depends on the line flows, line constraints, generators’ location and its share to the individual loads. This issue cannot be overlooked as it creates monopoliness which is against the deregulated market policy. The objective of this paper is to study the impact of market power when FACTS devices like thyristor controlled switching capacitor (TCSC) and thyristor controlled phase angle regulator (TCPAR) are used under steady state operation. The market power is determined using nodal must-run share (NMRS) index for the standard IEEE 14-bus system with and without the above FACTS devices and the results obtained are compared. All the above simulations are conducted in a MATLAB 7.9-R2009b environment.     

TCSC的最优配置

TCSC的投运能够有效地提高电力系统暂态稳定性,由于TCSC价格昂贵,安装数量受到限制。文中以特征分析法、相关因子和TCSC的H∞控制器作为工具．以系统稳定和H∞指标作为最优配置目标来实现TCSC的最优配置。在扩展的Anderson试验电力系统模型中进行仿真,结果表明此方法可以提高多机电力系统暂态稳定性。     

基于TLS-ESPRIT算法的附加励磁阻尼控制抑制次同步振荡

基于TLS-ESPRIT算法进行次同步振荡研究,将发电机机械阻尼系数取为0,以时域仿真的角速度偏差信号构成的数据矩阵为基础,用TLS-ESPRIT算法高精度地辨识出次同步振荡中各模态的频率及其对应的衰减系数,并与现场测得的模态阻尼相比较,判断次同步振荡的稳定性.该方法在难以获得弹簧-质量块模型阻尼系数的情况下依然可以判断次同步振荡稳定性,并且适用于多机系统分析.进一步提出了基于TLS-ESPRIT算法的附加励磁阻尼控制(SEDC)设计策略,以IEEE第二标准模型SYS-2为研究对象,设计了SEDC的具体参数.仿真结果表明,所设计的SEDC能有效抑制次同步振荡.     

基于本地测量信号的TCSC抑制次同步振荡附加控制

越来越多的柔性交流输电系统（FACTS）装置应用于电网,成为可能的次同步振荡激发源,严重的次同步振荡将直接导致大型汽轮发电机组转子轴系的严重破坏,危及电力系统的安全运行。为了有效抑制次同步振荡,文中设计了基于测量阻抗提升系数（本地测量信号）的可控串联补偿（TCSC）控制次同步振荡方法,并通过建立包含火电机组的TCSC系...     

数模混合式实时仿真装置中含多质量块轴系的发电机模型及其在工程研究中的应用

介绍了数模混合式实时仿真装置中多质量块轴系发电机模型的构成及其在伊冯可控串补工程中的应用。为了抑制或消除次同步谐振 (SSR) ,中国电科院 TCSC课题组提出了一种新的微调控制方法——电压增量控制 ,其基本原理是在SSR条件下保持电容电压增量水平接近稳态波形 ,使大部分SSR电流仅能通过晶闸管控制的电感支路。此时 ,串联电容补偿装置 (TCSC)呈电感特性 ,因此抑制次同步谐振是该方法的固有特性。通过接入 TCSC物理模拟控制器所进行的试验研究 ,验证了该方法在理论上是正确的 ,应用此策略的TCSC控制器可以有效地抑制或消除次同步谐振。     

可控串补用于暂态稳定控制的模拟试验研究

介绍了“东北伊敏－冯屯５００ＫＶ可控串补研究”项目的“控制规律及系统暂态稳定ＴＮＡ试验”。根据系统分析组提出的各种控制策略,利用实际控制器和串联电容补偿装置物理模型,在暂态网络仿真系统上进行了暂态稳定控制的物理模拟试验研究,对各种控制算法进行了相应的分析和比较。