武汉华大电力自动技术有限责任公司

<正>武汉华大电力自动技术有限责任公司座落于武汉国际企业中心,由武汉华工大电力自动技术研究所重组而成,是华中科技大学产业集团下属企业。主要产品公司开拓生产的电气类强电专业的教学实验设备如WDT-IIIC型电力系统综合自动化教学试验系统、PS-5G型电力系统微机监控试验系统、DJZ-IIIC型电气控制及继电保护综合试验台等,曾多次获得省优秀教学成果奖,并在国内100多所院校得到应用。公司生产微机励磁调节器已有近二十年历史,是最早将微机励磁     

DF8B型机车微机励磁时功率异常的处理方法

对DF8B型机车微机励磁时功率异常的原因进行了分析,从微机系统方面介绍了自负荷状态下机车功率异常的处理方法。     

基于87C196CA的双微机励磁调节器的研究与开发

励磁系统是同步发电机的重要组成部分.文章介绍了一种新型的基于87C196CA单片机的双微机励磁调节器,详细介绍了它的调节器特点和软硬件系统设计.     

非线性励磁控制器的研究

同步发电机励磁控制器是电厂中十分重要的控制设备,结合传统PID控制对非线性励磁控制方式进行有效的改进.DSP控制器与可编程逻辑器件CPLD为核心组成的微机励磁控制器,具有很好的应用前景.     

东风8B型机车励磁控制开关的改进建议

1 问题的提出1999年下半年至2000年底,我段为满足徐州至郑州间大列货物牵引的需求,先后配属28台东风8B型大功率电传动内燃机车,该型机车采用280型柴油机,装车功率可达3680kW,采用了防空转和防滑行微机控制(励磁一)和油马达(励磁二)两套恒功励磁控制,以保证柴油机在工作范围内恒功率运行.机车设有励磁控制开关供乘务员自行选用励磁方式.当选用的微机励磁系统发生故障时,则将控制手柄退回0位,然后把励磁控制开关拨至励磁二位即转换为油马达励磁方式,正常情况下应优先选用励磁一控制.     

基于非线性模型的励磁控制系统仿真研究

本文针对同步发电机的励磁控制系统,基于经典的PID方案和现代的状态反馈(SFB)方案,设计了几种新型的励磁控制方案,同时,比较了这些方案与常规的PID、PID加PSS和SFB方案对励磁控制系统的影响,所用模型为非线性。仿真结果表明,本文所提出的几种控制方案对于提高电力系统运行的品质指标、抑制系统的振荡、增加系统的鲁棒性等是有益的,并且利于用微机实现。     

DF8B型机车励磁二工况增加电阻制动功能

设计了DF8B型机车励磁二工况增加电阻制动功能的技术改造方案,励磁二电阻制动电路简单、工作可靠、微机不参与控制,大幅度降低了电阻制动故障率.     

华能澜沧江小湾电站励磁系统的设计与应用

介绍了小湾电站励磁系统中励磁变压器的设计计算方法和可控硅整流、灭磁和过压的设计以及调节器软件的各种功能,指出了小湾电站励磁系统中的创新点。总结已投运大型水轮发电机组的设计经验,对大容量水轮发电机组励磁系统的设计具有参考意义。     

电厂发电机励磁系统的节能控制模型仿真分析

摘要： 电厂发电机励磁系统具有非线性、强耦合的特点,能耗较大。提出基于模糊自适应算法的电厂发电机励磁系统节能控制模型,给出节能控制模型输入输出变量的确定过程和相应的模糊控制规则的设计步骤,把经模糊推理得到的输出模糊变量通过反模糊化过程变成精确量,设计模糊隶属度函数。采用模糊自适应算法设计电厂发电机励磁系统节能控制模型并搭建仿真环境,对存在干扰时2种模型节能控制效果和电厂发电机励磁系统出力情况分别进行了实验仿真和实验结果的比较分析。由实验分析结果可知,文中构建的模型较PID模型具有更强的抗干扰能力,能更有效地降低节能控制模型的超调量;该励磁系统模型的负荷率较低,基本能维持全天最低出力。     

水电站微机发电机转子接地保护装置的原理与设计

叙述了水电站综合自动化系统中微机发电机转子接地保护装置的基本原理、软硬件设计。本装置以高速高性能微处理机及实时多任务操作系统为基本开发手段，利用切换采样原理构成机组励磁回路一点和两点接地保护，测定转子接地故障点位置和过渡电阻的大小。     

基于反推方法的滑模自适应励磁控制

针对电力系统参数摄动和外界干扰等因素对励磁系统的影响,经过对传统模型状态变量的变换,建立了励磁控制系统模型,设计了基于backstepping方法的模糊滑模励磁控制器。该方法通过逐步构造Lyapunov函数和设计切换函数．从而得到了最终的控制规律。最后对所设计的算法进行了仿真研究,与常规PID＋PSS控制方法相比,系统在动静态响应性能上均优于PID＋PSS控制。通过仿真表明这种控制方法不仅有效而且还能达到比较满意的控制效果。     

A fuzzy logic excitation system for stability enhancement of powersystems with multi-mode oscillations

A fuzzy logic excitation system has been proposed to enhance the overall stability of power systems. The proposed excitation system has two control loops. One is the voltage control loop which achieves the automatic voltage regulator (AVR) function, and the other is the damping control loop which gives the PSS function. Simple fuzzy logic control rules are applied to both loops. The input signal to the voltage control loop is the terminal voltage, and the input signal to the damping control loop is the real power output. Simulation studies show the advantages of the fuzzy logic excitation system     

考虑发电机励磁的AC/DC系统模型与控制器设计

针对高压直流输电系统(HVDC)与发电机励磁协调控制问题,建立了HVDC和发电机励磁综合控制模型,采用微分几何变换法进行部分线性化获得了与原系统相同定性行为的线性系统.基于该线性化模型设计了控制方案并对控制器进行仿真.仿真结果表明,验证了控制器的有效性、可靠性,易于实际应用.     

EX21OOe励磁系统故障诊断与预警优化

励磁系统的运行与发电机及电力系统稳定性息息相关。EX2100e系统是目前GE公司燃气轮机的主 流励磁 系统,该系统 、输出信息少,与国产励磁系统差异较大,不利于运行维护人员及时发现 并处理故障。针对这种 ,对该系统的保护、故障报警进行了分析梳理,并实施了故障 化方案, 提升了系统 靠性。     

Excitation system protective limiters and their effect on volt/VArcontrol-design, computer modeling, and field testing

The action of excitation system protective limiters and VAr regulation are often not taken into account in planning studies, and actual units may be quite different than simulations. This may lead to incorrect predictions of actual stability limitations, or even voltage collapse phenomena. The design of the excitation system protective limiters such as over excitation limiters (OEL), under excitation limiters (UEL) and volts/hertz (V/Hz) is explained, and models presented. For system events where these controls and limiters may become active, modeling in transient stability studies is important to correctly predict volt/VAr performance. Specific models applicable to the GE EX2000 digital-based control systems are shown for reference, although the general concepts discussed here are applicable to any other excitation equipment. An important aspect of the new digital-based excitation controls is that they allow for more intelligent limiter functions and protective features not convenient with older equipment. Test procedures and results are shown to illustrate the limiter performance     

Integrated fuzzy logic generator controller for stabilityenhancement

An integrated fuzzy logic controller is proposed in this paper for the generator excitation and speed governing control. The proposed controller has three control loops: the first one is the voltage control loop which has the function of automatic voltage regulator (AVR), the second one is the damping control loop which has the function of power system stabilizer (PSS), and the last one is the speed governing control loop which has the function of governor (GOV). A simple fuzzy logic control scheme is applied to all these three loops. The control scheme is simple enough so as not to require heavy computation for the controller, therefore, its real time application is feasible. The effectiveness is demonstrated through nonlinear simulations using a one machine infinite bus system. Comparison studies are also performed to show the advantages of the proposed controller with conventional excitation and speed governing control systems     

凸极式发电机励磁与非理想STATCOM的协调控制

传统的含STATCOM的电力系统控制方法均采用STATCOM理想模型,即假定接入点的电压与电流相位差恒为90度,而在实际运行中根据不同的工况此角度可为任意值。考虑非理想STATCOM和凸极式发电机模型,首先建立了系统具有代数约束的非线性模型,分析STATCOM接人点的电压与电流相位差为任意角时控制情况的复杂性;进而利用几何反馈线性化理论并结合经典的线性二次型最优控制方法,给出了凸极式发电机励磁与STATCOM装置的协调控制设计方法;最后用一仿真算例验证了所提出方法的正确性和有效性。     

Experimental verification of fuzzy excitation control system formulti-machine power system

A fuzzy excitation control system (FECS), based on the fuzzy theorem and having the function of both AVR and PSS, was established to improve power system stability. This paper includes the results of experiments of the FECS on the AC/DC power system simulator of the CRIEPI. The FECS is compared with the conventional quick-response excitation system with optimized PSSs on a 4-machine long distance fish-bone type power system and various system configurations. The results show that the FECS increases the power transfer limit more than 20 (%) without any parameter tuning     

Stability investigation of a longitudinal power system and itsstabilization by a coordinated application of power system stabilizers

This paper presents the results of a stability investigation of a power system with longitudinal structure and its stabilization by coordinated power system stabilizers (PSSs). The effects of the existing controllers on system stability are studied. If no PSSs are present, the damping of various swing modes in the system will be very poor and low frequency oscillations present. Eigenvalue analysis shows that the undamped modes are sensitive to excitation control while speed governors have little influence on damping. In order to enhance the overall system stability through excitation control, a coordinated design procedure for power system stabilizers has been developed based on generation coherency, total coupling factor and nonlinear simulation. A PSS designed using this procedure is robust to different operating conditions and very effective for damping oscillations. Comprehensive simulation studies were conducted and results are presented     

A Self-Tuning Stabiliser for Excitation or Governor Control of Power Systems

Recently there has been increasing interest shown in utilising self-tuning control for stability enhancement of power systems. This paper proposes a new method of designing a self-tuning stabiliser for excitation or governor control for stability enhancement of power systems. In this method, a linear discrete-time model of preassumed order is used for the stabiliser design. Based on this model, a modified version of a conventional quadratic performance index is so defined that upon minimization, the resulting optimal stabiliser possesses an additional derivative term not found in the conventional stabiliser. The method also employs the recursive least squares algorithm for the purpose of estimating the model parameters every sampling interval. Based on the latest parameter estimate, the optimal stabilising signal is computed and applied to the power system under control. The proposed strategy is, therefore, self-tuning. Fig. 1 shows the block diagram of the proposed strategy for self-tuning excitation or governor control of a power system. An advantage of the derivative control term is that it possesses an anticipatory characteristic and initiates an early stabilising action. Consequently, the proposed self-tuning stabiliser is suitable for improving the damping characteristics of power systems. In fact, simulation results show that the damping characteristics of a power system, under different disturbances and over a wide range of operating conditions, can be enhanced when the proposed stabiliser is applied to the excitation or governor loop. Fig. 2 shows a set of typical nonlinear test results.