Intelligent Networked (N M) Fault Tolerant Systems for Hydropower Station

智能网络化为（Ｎ＋Ｍ）容错系统实现提供了一条切实可行途径,本文提出了其实现的基本思想和基本方法,并着重讨论其体系结构和智能容错策略．在此基础上,给出了一种基于现场总线的水电站智能网络化（Ｎ＋Ｍ）容错系统的实现方法．这种实现方法具有结构简单,安装维修方便,系统投资少,可靠性高,互操作性强等独特优点,因而具有良好的应用前景．本文提出的基本思想和基本方法不但适用于水电站的调速系统,对其它工业系统也有普遍意义     

基于事件触发机制的网络化风能转换系统鲁棒容错控制

本文对存在传感器和执行器故障的变速风能转换系统,提出了一种基于事件触发通信机制的鲁棒容错控制方法.建立了具有事件触发机制的非线性风能转换系统Takagi-Sugeno模糊模型模型.通过李雅普诺夫稳定性分析理论,给出了具有事件触发机制的风能转换系统鲁棒容错控制器的参数化表达式.与现有的风能转换系统容错控制方法相比,该方案...     

面向设备的水电站辅机系统建模方法研究

针对水电站辅机系统设备多、过程复杂的特点,提出了一种面向设备的水电站辅机系统建模方法,首先将水电站的生产过程层次化并将仿真对象分解成不同层次的基本组成单元,将具有相似功能属性的基本单元抽象成元件类,基于agent原理对元件进行建模,并建立了能够主动实现功能的标准元件结构,令元件能够主动的响应外界的事件触发并实现元件之间的信息交互;最后按照仿真对象的实际构成通过元件的交互接口组合成设备,令辅机系统的动态过程以功能涌现的形式反映。该方法在龙滩水电站仿真培训系统中得到了应用,不仅完整再现了水电站辅机系统的工作原理及其在水电站安全生产中的作用,且响应和效果逼真,提高了培训效果。     

基于CATIA的水电站引水系统三维设计探讨

针对水电站引水系统常规设计方法的不足,提出了基于CATIA的水电站引水系统的三维设计方法,并以复杂调压室体型设计为例,采用CATIA建立其几何模型,利用CFD软件分析其水力特性,实现了CATIA和CFD软件的联合使用,为水电站引水系统的设计提供了一种新途径。     

基于改进Seq2Seq模型的电力智能客服系统设计方法研究

随着电力用户规模不断增长、业务量不断扩大,传统客服模式已不能满足繁重的用户业务咨询需求,在此背景下设计一种精准的客户服务模式就显得至关重要。针对这一需求,文章首先提出了一种融合注意力机制+双向长短期记忆网络+双向门控循环单元(Attention+BiLSTM+BiGRU)的序列到序列(Seq2Seq)模型;然后通过对上下文语义信息的深层时序特征提取及赋权,有效提高了模型对话性能;最后通过算例仿真,实验结果从定性和定量的角度验证了所述方法具有回答效果更佳、问题识别能力更高的特点,对在线电力智能客服系统的设计和实现具有一定的参考价值。     

智能电站SCADA系统组态软件实现技术

介绍了智能电站数据采集与监视控制(SCADA)系统组态软件实现的相关技术,通过采用面向对象的动态建模思想、复合应用思想及富客户机平台(RCP)技术,使得组态软件具有通用性、扩展性、封装性。该组态软件不仅可以应用到智能电站和智能电厂领域,而且可以应用到其他领域。     

喷油压力的智能权函数模糊控制仿真研究

柴油机燃油喷射的控制高精度、响应快速度是保证其燃油经济性、排放清洁性的基本要求,所以本文利用智能权函数的改进模糊控制方法来实现对燃油系统的快速、精确控制,并对燃油压力阶跃升高控制进行仿真.仿真结果表明,该改进模糊控制方法相对PID控制而言,具有更好的控制稳定性和时效性,是一种具有广泛应用前景的智能化控制方法.     

基于注意力机制和多传感器信息驱动模型的水轮发电机组故障预测系统

为满足水轮发电机组在大数据背景下的故障预测需求，结合注意力机制特征提取能力强的特性和多传感器信息驱动可提高模型鲁棒性的优点，提出了一种基于注意力机制和多传感器信息驱动(Bi-GRU-Attention)模型的水轮发电机组故障预测系统，并将其应用于湖南省某水电站^#8机组8月在线监测数据中。实际运行结果表明，该系统有效预测了水轮发电机组的振动趋势，实现了水轮发电机的智能预测。     

计算机网络对智能电网安全的有效保护机制分析

摘要： 传统的保护方法采用时帧分布调节方法实现智能电网网络信道交叉映射,实现过载保护和网络节点管理,容易导致智能电网计算机网络节点信道偏移,数据丢包率较高,安全性差。提出基于端到端数据融合滤波的具有容错性的计算机网络下智能电网安全保护机制。构建计算机网络下的电网节点优化分布模型,采用网格形式部署,对过载节点进行数据融合与滤波处理,提高电网节点的容错性能;采用预加重方法补偿智能电网计算机网络节点之间的系统功率衰减,实现安全保护优化。仿真结果表明,采用该算法能准确实现对智能电网中的网过载的失调节点定位,电网进行能量传输稳定性较高,抗干扰性能较好,有效实现了电网的安全保护。     

三相八开关容错逆变器驱动PMSM系统模型预测直接转矩控制

针对三相八开关容错逆变器的PMSM驱动系统,提出模型预测转矩控制(MPTC)策略,并根据驱动系统的运行模式建立数学模型。取值设计复杂性和定子电流总谐波失真(THD)值的降低可利用改进型的MPTC策略来实现,且该策略还可减少磁链以及转矩脉动。利用电流反馈特性的容错控制可有效抑制直流侧母线电容分压不均衡的问题。通过仿真结果可知,该方法不仅具有良好的动态性能、较强的抗干扰性以及鲁棒性,还能降低其开关的损耗和定子电流的总谐波失真值,从而保证系统的可靠性和稳定性。     

B/S模式下的振动远程故障诊断系统

介绍了大型汽轮发电机组振动远程故障诊断系统的设计思路、基本构成以及实现方式。应用专家系统基本原理，提出了层次分类的故障思想。采用支持与否定规则表达征兆对故障诊断所起的作用。使用数据库技术对振动数据进行有效的管理。结合Activex控件技术，开发了振动远程故障诊断系统，实现了B／Ｓ模式下的远程诊断。     

敏感设备电压暂降敏感度模糊评估方法

提出了基于模糊理论的敏感设备电压暂降敏感度评估方法。暂降期间设备从安全到故障存在一个过渡过程,提出将这一过渡过程作为模糊极限过程．用设备隶属于安全状态的隶属度进行描述。利用能量函数作为设备隶属于安全状态的隶属函数,并结合正态分布函数刻画系统扰动和设备耐受曲线的随机分布规律。系统扰动和设备耐受曲线的概率密度函数参数分别由IEEE30节点仿真数据及实际测试数据得到。仿真结果验证了所提方法的有效性和准确性。     

Operating policies for wind-pumped storage hybrid power stations in island grids

Pumped storage is today viewed as the most suitable storage technology for achieving high wind penetration levels in multi-megawatt-sized autonomous island grids, where the technical constraints introduced by the conventional generating units impose limitations on the output of wind farms. In this study, an operating policy is proposed for hybrid wind-hydro power stations (HPSs) in island grids, to increase wind penetration levels, while at the same time minimising the impact on the conventional generation system and ensuring the viability of the HPS investment. The proposed operating strategy is applied to three different autonomous island systems using a dedicated logistic model, to evaluate the effect of the HPS on the overall operation and economics of the island systems and to assess the feasibility of HPS investments.     

Resolving the impact of distributed renewable generation on directional overcurrent relay coordination: a case study

Two approaches are proposed to solve the directional overcurrent relay coordination problem associated with the installation of distributed renewable generation (DRG) in interconnected power delivery systems (IPDS), depending on the existing system protection capability (adaptive or non-adaptive). For adaptive protection systems, the first proposed approach introduces a procedure to select the optimal minimum number of relays, their locations and new settings. This procedure is restricted by the available relay setting groups. For non-adaptive protection systems, the second proposed approach implements a practice to obtain optimal minimum fault current limiter values (FCL) to limit DRG fault currents and restore relay coordination status without altering the original relay settings. An integration of the proposed two approaches is evaluated for IPDSs possessing both protection systems. Three scenarios are assessed for different numbers of DRGs, and DRG and fault locations using an optimisation model implemented in GAMS software and a developed MatLab code. The obtained results are reported and discussed.     

Wind turbine asymmetrical load reduction with pitch sensor fault compensation

Offshore wind turbines suffer from asymmetrical loading (blades, tower, etc), leading to enhanced structural fatigue. As well as asymmetrical loading different faults (pitch system faults etc.) can occur simultaneously, causing degradation of load mitigation performance. Individual pitch control (IPC) can achieve rotor asymmetric loads mitigation, but this is accompanied by an enhancement of pitch movements leading to the increased possibility of pitch system faults, which exerts negative effects on the IPC performance. The combined effects of asymmetrical blade and tower bending together with pitch sensor faults are considered as a “co‐design” problem to minimize performance deterioration and enhance wind turbine sustainability. The essential concept is to attempt to account for all the “fault effects” in the rotor and tower systems, which can weaken the load reduction performance through IPC. Pitch sensor faults are compensated by the proposed fault‐tolerant control (FTC) strategy to attenuate the fault effects acting in the control system. The work thus constitutes a combination of IPC‐based load mitigation and FTC acting at the pitch system level. A linear quadratic regulator (LQR)‐based IPC strategy for simultaneous blade and tower loading mitigation is proposed in which the robust fault estimation is achieved using an unknown input observer (UIO), considering four different pitch sensor faults. The analysis of the combined UIO‐based FTC scheme with the LQR‐based IPC is shown to verify the robustness and effectiveness of these two systems acting together and separately.     

Optimum sizing of wind-pumped-storage hybrid power stations in island systems

Pumped storage is generally viewed as the most promising technology to increase renewable energy source (RES) penetration levels in power systems and particularly in small autonomous island grids. Combined wind and pumped-storage “virtual power plants”, called hybrid power stations (HPS), constitute a realistic and feasible option to achieve high penetrations, provided that their components are properly sized. In this paper, the optimum sizing is investigated for a pumped storage HPS operating in an island system. The analysis addresses the sizing of the main HPS components (hydro turbines, pumps, wind farm, reservoirs), adopting either the investor’s perspective, where the objective is to maximize the return on the HPS investment, or a system perspective, where the optimization target is the maximization of RES penetration, along with maintaining the lowest possible generation cost in the system. Genetic Algorithms (GAs) are applied for the optimization and a real isolated island power system is used as a study case. The adopted operating policy and pricing principles, which critically affect the optimal sizing of an HPS project, are based on the existing regulatory framework for storage stations in Greek islands.     

Fault detection and diagnosis methods for green hydrogen production: A review

One of the green hydrogen projects is Zero Emission Hydrogen Turbine Center (ZEHTC), in which solar panels, PEM electrolyzer, and diaphragm compressor are used to generate power, produce hydrogen and store hydrogen at high pressure, respectively. Faults in any components of photovoltaic (PV) systems, PEM electrolyzers, and diaphragm compressors can seriously affect the efficiency, energy yield as well as security, and reliability of the entire system, if not detected and corrected quickly. In this paper, the types and causes of PV systems, PEM electrolyzer, and diaphragm compressors failures are presented, then different methods proposed in the literature for fault detection and diagnosis (FDD) of systems are reviewed and discussed. Special attention is paid to methods that can accurately detect, localize and classify possible faults occurring in a PV arrays. The advantages and limits of FDD methods in terms of feasibility, complexity, cost-effectiveness and generalization capability for large-scale integration are highlighted. Based on the reviewed papers, challenges and recommendations for future research direction are also provided. In this work different model-based approaches are investigated as well as their validation and applications. An overview of different methodologies available in the literature is proposed, which is oriented to help in developing suitable diagnostic tool for PEM electrolyzer monitoring and fault detection and isolation (FDI). Model-based methods provide fault detection and identification, are easy to implement, and could be conducted during system operation.     

燃气轮机控制系统故障树的自动建造

通过一个燃气同间接作用式定压差流量控制系统自动建树的实例,阐述了一种燃气同控制系统多态故障树的自动建造方法。该方法使用简单,可达到较好的建树效果。此种方法也可用于一般控制系统故障树的自动建造,具有通用性。     

Wavelet transform-based fault detection method for hydrogen energy-based distributed generators

Integration of hydrogen energy-based distributed generators (HEBDGs) to the main grid causes some power quality (PQ) problems. The conventional fault detection methods fail to detect some PQ disturbances, thus intelligent methods are proposed in the literature recently. This paper focuses on developing a wavelet transform (WT)-based fault detection method for HEBDG systems to detect PQ disturbances in the low-voltage grid connection. The proposed method uses the discrete WT and Daubechies wavelets of order 4 to detect the voltage swell, voltage sag, voltage interruption and transient disturbances in a HEBDG system. The performance of the WT-based method is also compared with the conventional fault detection methods, and using the time-frequency domain analysis by WT increases the stability of the proposed method. The results verify that the conventional methods are not capable of detecting some PQ disturbances properly, but the proposed WT-based method is more reliable according to the conventional methods.