贵州电网AGC安全约束控制策略的研究与实现

随着“西电东送”、“黔电送粤”战略的实施,贵州电网进入了一个飞速发展的时期。外送电和省内负荷增加,发电出力、负荷分布的不均衡,以及电网建设的相对滞后,造成了电网部分断面在某些运行方式下接近或超过安全约束的情况,给电网运行带来了一定风险,利用发电厂AGC来帮助调度员进行潮流的合理控制,对保证电网的安全、稳定、优质运行十分必要。从控制策略、控制算法、数据结构和人机界面等方面讨论了AGC对网架断面潮流控制的实际问题,提出了兼顾ACE的具体控制策略(包括预防控制策略和校正控制策略)和实现方案,并通过实例对方案进行了验证。     

多控制区协调自动发电控制的研究与实现

为了解决电源送出问题,提出一种多控制区协调自动发电控制(AGC)模型。结合该模型,对AGC的行为与电网潮流之间的作用关系进行分析,给出了相应的控制策略及控制算法。主控制区的控制目标为频率和联络线偏差控制,子控制区的控制目标为其稳定断面潮流贴近控制要求。子控制区也可参与主控制区的控制,实现与主控制区的协调控制。在云南省调AGC的实际工程应用表明,该方法可以有效地将子控制区稳定断面有功功率控制在允许范围内,保证电力系统的安全稳定运行。     

The advanced set-up and control system for Dofasco's tandem coldmill

The new coupled pickle line and cold mill (CPCM) has been processing steel since December 1991 at Dofasco Inc. in Hamilton, Ontario, Canada. This mill rolls both sheet and tin plate. The work rolls for the last stand are often textured by grit blasting to roll “matte” finished strip. A new computer-targeted control system was developed for the roll speeds and gaps, specifically for matte rolling. The new set-up system uses Stone's model, which is more appropriate for the limited reductions evident with the rougher rolls. Conventional automatic gauge control (AGC) systems using thickness measurements after the last stand are limited in performance by the effect of long transport delays. These limitations are particularly critical during mill acceleration and deceleration. The use of a thickness gauge before the stand with matte rolls allows the development of AGC systems using shorter control loops for final gauge control. The AGC system uses a Smith predictor for transport lag, (phase shift), and compensation. The combination of the shorter AGC loop and the Smith predictor allows higher gains to be used in the control system. This set-up and control system has contributed to Dofasco's position as a market leader in thickness performance     

Automatic generation control of power system using a novel quasi-oppositional harmony search algorithm

The present work approaches a novel quasi-oppositional harmony search (QOHS) algorithm, as an optimization technique, for its optimum performance in the subject area of automatic generation control (AGC) of power system. The proposed QOHS algorithm is applied with an aim to converge rapidly towards the optimal solution(s) that houses both the characters of two guesses, i.e. opposite-point and quasi-opposite point. The area of concern of this study is to discuss the multi-objective problems of an interconnected power system for the benefits of AGC. The proposed QOHS algorithm is, individually, applied to single-area, precede to two-area considering the non-linearity effects of governor dead band and generation rate constraint and, finally, extended to four-area power system showing the consequences of multiple load disturbances. A case of robustness and stability analysis are also investigated for the studied two-area power system model. The control strategy, for the dynamic power system model, is based on area control error. The simplicity of the structure and acceptability responses of the well-known proportional–integral–derivative controller enforces to implement as a controller in this work. The comparative evaluation of the proposed QOHS algorithm is carried out by the way of comparing the dynamic performances of the studied power system model with those offered by other algorithms reported in the recent state-of-the-art literature. The simulation works, presented in the paper, reveal that the proposed QOHS algorithm may be effectively utilized for the purpose of AGC study of power system having varying degrees of complexities and non-linearities. Moreover, the proposed QOHS based control strategy adopted in this work provides a robust and stable speed control mechanism.     

并行前馈给水控制策略及其在1000MW机组应用

火电机组辅机故障减负荷(RUNBACK,简称RB)的成功对保证机组稳定可靠运行意义重大。针对1 000 MW超超临界机组发生RB工况时的锅炉给水控制进行分析,提出了采用动态并行前馈的锅炉给水流量调节控制策略,给出前馈信号在给水泵投入台数发生变化时的无扰处理以及RB过程给水流量调节加速的方法。在海门电厂实际试验结果表明,所提出的控制策略能实现稳定、准确的给水控制。     

Application of a new automatic gauge control system for the tandemcold mill

In July 2000, a new automatic gauge control (AGC) system was successfully installed at the Kakogawa Works, Kobe Steel, Ltd., Hyogo, Japan. The new AGC system consists of two functions: multivariable AGC based on mass flow thickness; and roll eccentricity control. The multivariable AGC is designed using inverse linear quadratic theory, a type of optimal control theory, and controls both thickness and tension. Repetitive control theory is applied to roll eccentricity control as roll eccentricity is a periodic disturbance related to the rotational angle of the rolls. The new AGC system has contributed to improved thickness accuracy and stable rolling. In this paper, details of the new AGC system are described and the application results are shown     

球磨机新型控制策略研究与应用

球磨机制粉系统是电厂除锅炉燃烧系统外的又一重要调节系统。该系统具有多变量强耦合、非线性严重以及生产工况变化大等特性,采用常规控制策略很难奏效。在对球磨机动态特性分析的基础上,提出了一种新型控制策略。该控制策略采用软测量技术获取磨负荷信息,通过协调器实现对球磨机的磨负荷和出口温度的有效控制。通过控制热、冷风量的比值实现对球磨机入口负压的控制。控制器均采用模糊PID控制算法,以确保动态响应和稳态精度。实际运行效果表明,该控制策略具有简单、可靠、实用等特点。     

多种群蚁群优化算法在大型水电站自动发电控制机组优化组合中的应用

为求解大型水电站自动发电控制(automatic generation control,AGC)机组优化组合问题,提出一种多种群蚁群优化算法.同时,综合考虑水量、电量平衡,水库、机组运行限制等多重安全生产约束条件,提出了一种流量—水头—出力的循环迭代策略确定时段动态水头,并引入基于机组启停优先顺序表的系统备用容量修补技...     

风电并网下计及机组特性的AGC动态优化控制策略研究

风电的大量接入产生复杂的互联电网运行特性,这需要电网AGC能及时响应能源与负荷的快速、大范围的变化,并根据AGC机组的动态特性发布有效指令,既能进行多时段连续的协调控制,又能保证电网运行的经济性。为此,论文建立了考虑AGC机组动态特性,又考虑风电快速、大范围波动情况下的AGC动态优化控制策略模型。该模型权衡动态优化过程中经济性和指标性的比重,兼顾CPS评价标准,综合发布多时段连续的协调指令。该控制策略模型是一个多约束,大规模,多时段的复杂优化问题,因此采用PSO算法求解运算,结合运行的实际特征,对越限的粒子进行有效处理。通过对某区域AGC策略计算,验证了本控制策略无论是AGC调节费用,还是电网频率或CPS指标等均优于传统的控制策略。     

风力发电机的恒功率控制

针对大型风力发电机组因反馈信号滞后引起的输出功率波动进行研究。在研究了传统转速反馈PI控制和基于测量风速前馈控制的基础上,提出了基于有效风速估计的前馈与功率反馈PI结合的变桨控制策略,通过牛顿-拉夫逊算法进行有效风速估计,根据有效风速估计值给出合适的前馈桨距角,实现动态前馈补偿。基于Fast软件平台开发的外部控制器,对恒功率控制提出的控制策略与传统的控制策略进行仿真比较。仿真结果表明：相对传统的控制策略,提出的前馈控制使风力发电机组能够保持稳定的电功率输出。     

Active compensation of roll eccentricity in rolling mills

This paper is concerned with the active compensation of the roll-eccentricity-induced periodic disturbances in the strip exit thickness of hot and cold rolling mills. The roll eccentricity may be caused by different reasons, e.g., inexact roll grinding or nonuniform thermal expansion of the rolls. The increasing demands on the thickness tolerances require new methods for the active compensation of the contribution of the roll eccentricity to the final thickness deviation. The presented method is based on the factorization approach over the set of stable transfer functions in combination with an adaptive least-mean-squares algorithm derived from the projection theorem. Here, the authors take advantage of the fact that the eccentricity-caused disturbance is periodic with a frequency proportional to the measured angular velocity of the rolls. Furthermore, it turns out that the presented concept fits the conventional control circuit of automatic gauge control in an optimal way. Simulation results for a cold rolling mill and measurement results for a hot strip mill demonstrate the feasibility and the excellent performance of the design     

伴随AGC机组控制过程的潮流模型与算法

针对自动发电控制(automatic generation control,AGC过程中难以把握潮流状态的问题,在安全经济调度确定的AGC机组的基点、参与因子,以及超短期负荷预报提供节点分配因子和功率因数变化规律的基础上,结合动态潮流电热耦合潮流等概念,利用实时区域控制偏差(area controerror,ACE)信号,建立了伴随AGC机组控制过程的潮流模型和算法。实际算例对所提模型和算法进行了验证,结果表明,在跟踪AGC控制过程中计算潮流非常重要,这对于跟踪输电线路温度变化,监视系统安全性能等都是有益的。     

经济AGC控制装置在机网协调技术中应用

提出自动发电控制(AGC)的平滑控制和"负荷断点"问题,并给出解决该问题的实际应用方案.在发电机组AGC运行模式的基础上,通过"经济AGC控制装置",根据入炉煤的发热量变化.建立煤的发热值数学模型.自动计算出需要启动或停止磨煤机的"负荷断点"位置.其主要控制方法为:某台机组在按照AGC指令升降负荷中遇到"负荷断点"时.可以把AGC的指令改控另一台机组.从而既保证了AGC负荷的连续性.又避免了磨煤机的启/停控制.     

基于PSO算法的多变量PID型神经元网络在球磨机控制上应用

为提高多变量、非线性和强耦合系统的动态特性和解耦能力,基于PID控制的简单结构和良好性能优势以及神经元网络的自调节和自适应的特长,设计了具有PID结构的多变量自适应的PID型神经元网络控制器。给出了这种控制系统的结构和算式,其为一种3层前向神经网络,其隐层单元分别为比例(P)、积分(I)和微分单元(D),各层神经元个数、连接方式、连接权值的初值是按PID控制规律确定的。神经元网络参数采用了粒子群优化(PSO)学习算法,并给出了相关算式。分析了球磨机制粉控制系统的特点,并应用提出的控制方法对其进行了仿真研究,比较了文中控制方法与传统的PID控制方法的控制效果。仿真结果表明了所提方法具有较好的控制品质、良好的自适应解耦能力和自学习功能。     

改善电厂调频性能的储能策略研究和容量配置

具有快速充放电特性的储能技术,作为一种新的调频方式已逐步进入多国的辅助服务市场,参与到传统机组的自动发电控制(AGC)中。基于华北地区的辅助服务补偿政策,提出了改善电厂调频性能的储能充放电策略和容量配置方法。首先,根据政策中AGC考核指标Kp值的定义,提出调节速率、调节精度、响应时间3项指标的计算方法,并制定出提升调节性能、降低响应时间的储能充放电策略。同时,为了延长储能的使用寿命,制定了电池荷电状态的越限回归策略。在分析储能各项成本和收益的基础上,建立了以净收益最大为目标函数的储能经济性模型。最后,通过具体算例,对使用该策略前后机组的AGC性能进行对比分析并采用差分进化算法计算出了机组配置储能的最优容量。结果表明,使用储能策略可以显著提升机组的Kp值,带来明显的调频收益。     

Hamilton‐based adaptive robust control for the speed and tension system of reversible cold strip rolling mill

The adaptive robust control problem for the speed and tension system of reversible cold strip rolling mill is studied based on the Hamilton theory in this paper. First, the dissipative Hamilton model of the rolling mill system's speed and tension outside loop is built through pre‐feedback control, and then, dissipative Hamilton controllers are designed by utilizing the interconnection and damping assignment and the energy shaping method. Second, in order to realize tensiometer‐free control and adaptive robust control for the perturbation parameters and load disturbance, full‐order state observers and adaptive robust controllers are designed for the rolling mill system's speed and tension outside loop by using the “extended system + feedback” method. Third, robust controllers for the rolling mill system's current inside loop are designed based on the cascade control thought, so as to realize the tracking control for the speed and tension of reversible cold strip rolling mill. Theoretical analyses show that the resulting closed‐loop system is stable. Finally, simulation research is carried out on the speed and tension system of a 1422‐mm reversible cold strip rolling mill, and simulation results verify the validity of the proposed control strategy in comparison with the decentralized overlapping control strategy.     

互联电网CPS下AGC控制参数的优化

提出了一种在互联电网控制性能标准(CPS)下现有自动发电控制(AGC)系统的控制参数优化方法.根据电网真实或假设的系统频率、负荷等运行数据,建立了基于现代内点理论的互联电网CPS下的AGC策略模型,进行求解,以优化结果反推出影响CPS指标和AGC系统性能、调节次数的比例系数、积分系数、CPS分量系数等关键参数,并进行仿真计算,结果表明该方法减少了AGC机组的下令次数,大幅度提高了CPS指标,保证了电网频率质量和安全运行,为调度、自动化专业优化调整AGC主站端的控制参数提供了理论依据和数学工具.该成果已用于广西电网.     

储能调频系统控制策略与投资收益评估研究

本文以华北区域AGC补偿机制为基础,提出了电储能系统响应电网AGC指令的优化控制模型,模型以最大化电储能系统AGC运行的净收益为目标,考虑了电储能系统寿命损耗成本以及AGC补偿收益,并应用粒子群(PSO)算法求解最大化收益的控制策略。在算例分析中,基于电网实际下发的AGC指令,应用本文模型对锂离子电池储能系统的控制策略进行时序仿真,即首先对每个AGC指令周期优化储能系统的控制策略,然后计算电储能调频服务在整个仿真周期净收益,最后对储能调频系统的投资经济性进行评估。     

基于串级PI-(1+PD)算法的含飞轮储能互联电网AGC控制器设计

针对传统控制器存在的响应速度较慢、超调较大及鲁棒性较差等问题,提出一种基于串级PI-(1+PD)算法的含飞轮储能互联电网AGC控制器设计方法。首先,建立含飞轮储能的两区域互联电网AGC系统模型,模拟飞轮储能联合火电机组参与AGC的过程。然后,设计一种基于串级PI-(1+PD)算法的AGC控制器。外环采用PI控制,内环采用带滤波系数的(1+PD)控制。在保证系统稳态性能的前提下,提高动态响应速度和抗扰能力,并通过粒子群算法的迭代寻优获得最优的控制器参数。最后,基于Matlab/Simulink进行算例仿真分析。结果表明：与传统PID控制和PI-PD控制相比,所提方法不仅具有更快的响应速度与更小的超调量,而且增强了系统抵御内部参数摄动的鲁棒性。     

电网AGC与AVC协调控制方法

电力系统有功功率与无功功率耦合日益紧密,自动发电控制(AGC)与自动电压控制(AVC)相互解耦的模式会影响电网的运行控制效果。基于AGC与AVC不同的控制周期,在时间尺度上建立了分钟层和秒层两级衔接的AGC与AVC协调控制模式,提出了控制方法。在分钟层级上,建立有功功率与无功功率联合的最优潮流模型,提出AGC与AVC的联合优化控制方法;在秒层级上,完善AGC与AVC各自的控制策略,提出AGC与AVC的协调校正控制方法。通过算例验证表明,所提方法在满足AGC与AVC各自控制目标的同时,实现了电网的经济运行,抑制了AGC与AVC的相互影响,促进了AGC与AVC的相互支撑。