Antlion optimizer-ANFIS load frequency control for multi-interconnected plants comprising photovoltaic and wind turbine

This paper proposes optimal load frequency control (LFC) designed by Adaptive Neuro Fuzzy Inference System (ANFIS) trained via antlion optimizer (ALO) for multi-interconnected system comprising renewable energy sources (RESs). Two systems are modeled and investigated; the first one has two plants of grid connected photovoltaic (PV) system with maximum power point tracker (MPPT) and thermal plant while the second comprises four plants of thermal, wind turbine and grid connected PV systems. ALO is employed to get the optimal gains of Proportional–Integral (PI) controller such that the integral time absolute error (ITAE) of frequency and tie line power deviations is minimized. The input and output of the optimized PI controller are used to train the ANFIS-LFC with Gaussian surface membership functions. Different load disturbances are studied and the results are compared with other reported approaches. The obtained results confirmed the accuracy and reliability of the proposed approach in designing LFC for multi-interconnected power systems.     

万安核电站年最大风速的统计与天气分析

使用1970~2009年吉安、永新、万安、遂川和泰和五站气象资料,对核电站区域年最大风速及产生最大风速的天气系统,采用统计学方法和个例分析方法进行研究,结果表明:90年代前,万安核电站区域年最大风速在15m/s左右,90年代后,降至12m/s左右;各站自有记录以来,年最大风速表现呈缓慢降低的趋势,且从90年代后这种趋势更加明显.40a的208次最大风速样本统计表明,区域内影响天气可分为强对流天气大风(48.1%)、冷空气大风(21.2%)、热带气旋及台前环流大风(16.8)和其他大风(13.9)4种类型.年最大风速主要出现在春季和夏季,依次由强对流天气、冷空气、热带气旋及台前和其他天气系统影响所致.     

Event triggered state estimation techniques for power systems with integrated variable energy resources

For many decades, state estimation (SE) has been a critical technology for energy management systems utilized by power system operators. Over time, it has become a mature technology that provides an accurate representation of system state under fairly stable and well understood system operation. The integration of variable energy resources (VERs) such as wind and solar generation, however, introduces new fast frequency dynamics and uncertainties into the system. Furthermore, such renewable energy is often integrated into the distribution system thus requiring real-time monitoring all the way to the periphery of the power grid topology and not just the (central) transmission system. The conventional solution is two fold: solve the SE problem (1) at a faster rate in accordance with the newly added VER dynamics and (2) for the entire power grid topology including the transmission and distribution systems. Such an approach results in exponentially growing problem sets which need to be solver at faster rates. This work seeks to address these two simultaneous requirements and builds upon two recent SE methods which incorporate event-triggering such that the state estimator is only called in the case of considerable novelty in the evolution of the system state. The first method incorporates only event-triggering while the second adds the concept of tracking. Both SE methods are demonstrated on the standard IEEE 14-bus system and the results are observed for a specific bus for two difference scenarios: (1) a spike in the wind power injection and (2) ramp events with higher variability. Relative to traditional state estimation, the numerical case studies showed that the proposed methods can result in computational time reductions of 90%. These results were supported by a theoretical discussion of the computational complexity of three SE techniques. The work concludes that the proposed SE techniques demonstrate practical improvements to the computational complexity of classical state estimation. In such a way, state estimation can continue to support the necessary control actions to mitigate the imbalances resulting from the uncertainties in renewables.     

飞轮电池对风光互补发电系统电压波动的改善研究

在风光互补发电系统独立运行时,由于风速和光照强度的随机变化,风光发电单元的输出功率也会随之变化。负载功率也具有可变性,使得系统功率难以保持平衡,从而引起系统电压波动,影响电能质量。针对这一问题,该文将飞轮电池并联在系统的交流母线上,根据风光发电单元的输出功率和负载消耗功率的差值,采用双环控制策略控制飞轮电池的输出功率,实现系统功率平衡,达到抑制电压波动和改善电能质量的目的。最后对风光输出功率大于负载功率和风光输出功率小于负载功率这两种功率不平衡的情况进行了仿真分析,结果表明飞轮电池可以快速平衡系统的瞬时功率,稳定电压,满足电能质量的要求。     

极端天气下电网故障预警及风险评估模型

为分析台风、暴雨等极端天气对电网正常运行造成的影响并做出风险评估以作应对,提出了极端天气下电网故障预警及风险评估模型。分析了在极大风以及雷电天气影响下电网可靠性能以及风险评估,针对极端气象环境对电力系统的影响进行了分析,建立了极端天气条件下的电网故障评估模型,提出了电网韧性指标,利用 Credal 集合对可靠性评估进行分析,其中应用人工神经网络进行潮流计算。最后通过仿真分析论证了所提方法的有效性。     

TCR型SVC在风电并网领域中的应用

介绍了风力发电机组的并网技术,并分析了风电并网后给电网电能质量带来的不利影响;针对风电并网后对整个电网电能质量的不利影响,本文提出通过使用静止型动态无功补偿装置（SVC）来改善风电场的电压稳定性,降低电压波动和闪变,提高功率因数。为了说明SVC在稳定风电场电压和提高风电系统运行性能方面的作用,通过某风电系统中安装的SVC为例进行仿真说明。实际应用效果表明,SVC极大地改善了风电场运行性能,保证风电场并网电能质量符合国家标准。     

基于液压传导的风力发电系统研究

提出一种新型的液压传导储能风力发电系统模型。该模型采用液压系统传导储能,有效改善风电波动性,降低风机的制造维护成本,并实现功率及电压控制。通过液压传导将发电机及相关控制系统降至地面,能够降低一定的风机制造成本。通过对该模型的分析和实验,证明该新型系统能适用于中小型风力发电系统并且可以有效克服现有风力发电系统的一些缺陷。液压储能实现异时发电并改善风电的波动性,而通过调节液压系统来进行稳压,则无需电力稳压系统。     

液压储能在风力发电储能中的应用

风力发电系统为实现系统稳定和持续供电,必须配备合适的储能装置.因此提出以下设想:将风能首先转化为液压能,并以液压蓄能器作为储能装置.不但可以实现系统的稳定和持续供电,还可以将发电机等设备降至地面,大大节约塔架的建造成本和风机的维护费用,并实现通过液压调速回路稳定电压.在上述设想的基础上,设计了一套实验模型,针对液压储能的系统效率和稳压效果进行仿真分析,结果表明:液压系统效率为72.9%,发电电压波动幅度小于0.83%,效率和稳压效果都能满足要求.     

Fractional order fuzzy control of hybrid power system with renewable generation using chaotic PSO

This paper investigates the operation of a hybrid power system through a novel fuzzy control scheme. The hybrid power system employs various autonomous generation systems like wind turbine, solar photovoltaic, diesel engine, fuel-cell, aqua electrolyzer etc. Other energy storage devices like the battery, flywheel and ultra-capacitor are also present in the network. A novel fractional order (FO) fuzzy control scheme is employed and its parameters are tuned with a particle swarm optimization (PSO) algorithm augmented with two chaotic maps for achieving an improved performance. This FO fuzzy controller shows better performance over the classical PID, and the integer order fuzzy PID controller in both linear and nonlinear operating regimes. The FO fuzzy controller also shows stronger robustness properties against system parameter variation and rate constraint nonlinearity, than that with the other controller structures. The robustness is a highly desirable property in such a scenario since many components of the hybrid power system may be switched on/off or may run at lower/higher power output, at different time instants.     

基于再生能源的极地漫游机器人研究及现场试验

研制应用于南极地区进行科考,基于再生能源的极地漫游者机器人系统。根据南极地区特有的地形、地面条件、温度、风速等自然条件对机器人系统结构、驱动、控制和能源系统进行分析与设计。为满足在南极冰盖地区持续漫游的需要选择时间分布更为均衡的风能作为机器人能源方案,选择更适合该机器人结构的垂直轴风力发电机系统。为提高机器人能源使用效率而选择轮式驱动结构和轮内电动机方案。设计差动式连杆与可调式摆腿结构,提高其通过能力和平稳性。并赴南极中山科考站进行现场测试,结果表明该机器人对中山站站区附近不同地面条件的适应力较好,对障碍的通过能力满足要求,再生能源系统可为机器人提供稳定的能源供给。但现场试验也暴露出机器人转向模式、能源捕获效率和控制模式上与环境特点不匹配的问题,需要通过进一步研究和试验进行改进。     

小功率电动汽车用SR电机驱动与CAN通信系统设计

设计了一种低压小功率电动汽车用开关磁阻电机驱动系统,论述了基于IR2110的MOS-FET驱动电路的设计,采用89C51单片机与SJA1000CAN控制节点为核心,设计了基于CAN总线的电动机数据采集传输系统,简化了电动汽车线束.     

基于数据挖掘的风力发电设备在线故障诊断平台

为保证风电场大型风力发电机组安全、可靠、经济和优化运行,提出了一个基于数据挖掘技术的风力发电机组在线状态监测与故障诊断系统。并介绍了该系统的硬件、软件体系结构、网络技术及特点,给出应用实例说明其实用性和有效性。     

直激式压电风能捕获器的性能分析与实验

提出一种由压电梁及其端部附加质量构成的直激式压电风能捕获器。在考虑了压电振子静平衡变形的基础上,根据涡激振动理论建立了柔性压电振子的自激振动理论模型并进行了仿真分析,获得了压电梁厚度比、附加质量及风速对其发电性能的影响规律。结果表明,存在最佳的压电梁厚度比使输出电压、电能及功率最大,电压/电能/功率所对应的最佳厚度比分别为0.5/0.65/0.65。其它参数确定时,存在最佳风速/附加质量使输出电压最大,且最佳风速随附加质量增加而降低、最佳质量随风速增加而降低。制作了风能捕获器样机并进行了试验测试,风速为4.8/7.2/10m/s时,对应的最佳附加质量及最大电压分别为15/11/7g和1.9/3.94/6.18V;风速为10m/s时,10g附加质量下的输出电压为0/20g附加质量下的4.1/1.2倍。结果证明根据实际风速范围确定合理的附加质量可提高发电能力。     

柔性直流输电在中国电网中的应用前景

柔性直流输电是一种新型直流输电技术,它采用IGBT作为开关器件,以电压源换流站为核心。相对于传统的直流输电以及交流输电,柔性直流输电具有更广阔的应用前景。本文主要介绍了柔性直流输电的基本原理、技术特点和应用领域,综述了柔性直流输电的国内外发展与应用现状,并结合我国新能源及电网的发展特点,探讨了柔性直流输电在新能源并网,构建城市供配电网,孤岛供电,构建智能电网等领域的应用前景,提出了推广应用柔性直流输电的建议。     

Adaptive filter design based on the LMS algorithm for delay elimination in TCR/FC compensators

Thyristor controlled reactor with fixed capacitor (TCR/FC) compensators have the capability of compensating reactive power and improving power quality phenomena. Delay in the response of such compensators degrades their performance. In this paper, a new method based on adaptive filters (AF) is proposed in order to eliminate delay and increase the response of the TCR compensator. The algorithm designed for the adaptive filters is performed based on the least mean square (LMS) algorithm. In this design, instead of fixed capacitors, band-pass LC filters are used. To evaluate the filter, a TCR/FC compensator was used for nonlinear and time varying loads of electric arc furnaces (EAFs). These loads caused occurrence of power quality phenomena in the supplying system, such as voltage fluctuation and flicker, odd and even harmonics and unbalancing in voltage and current. The above design was implemented in a realistic system model of a steel complex. The simulation results show that applying the proposed control in the TCR/FC compensator efficiently eliminated delay in the response and improved the performance of the compensator in the power system.     

风光互补供电系统在自动气象站中的应用

利用四会观测站的年均日照时数和平均风速等资料,用太阳直接辐射量和风能计算公式,求得四会市年有效太阳辐射量和风能储量分别为984.9 kWh/m2和9.1 kWh（Φ2.2 m风轮）,结合观测站和乡镇中尺度区域自动站设备的耗电情况,计算出用普通风光互补供电系统可供给本站气象仪器设备使用88天、乡镇区域气象站全年不间断使用.该发电系统既可为气象部门节省能源开支,同时也符合构建现代资源节约型和环保友好型社会的发展要求.     

变速恒频风力发电技术综述

风力发电正在以前所未有的速度发展,变速恒频风力发电是一门新技术。简要介绍了风力发电机的组成和分类。通过和恒速恒频风力发电机进行比较,分析了变速恒频风力发电技术的优点。比较了几种适适用于变速恒频风力发电的发电机组,对各自的原理进行了比较详细的阐述。最后展望了风力发电的前景。     

Combining two techniques to develop a novel islanding detection method for distributed generation units

Renewable energy is a fast-growing sector given that it does not cause the pollution produced by nuclear and fossil generation systems. The use of renewable energy for distributed generation (DG) is important worldwide not only because it increases profits but also because integrating it into utility systems ensures power supply at points of consumption even when a DG system is disconnected from the main system. Researchers continue to exert efforts in improving islanding detection methods because current detection approaches remain unsatisfactory. Accordingly, this paper presents two new islanding detection methods that are suited for single and multiple DG units. The methods are based on the rate of change in active and reactive power, frequency, and voltage angle. They are tested on single and multiple DG systems with wind turbines and simulated using the Power World Simulator software. The simulation results show that the methods effectively reduce the time spent on islanding detection and efficiently decrease non-detection zones. To verify the accuracy and speed of the proposed methods, the results are compared with those achieved by different islanding detection approaches.     

电压跌落时双馈电机电磁暂态过程仿真与分析

双馈风力发电机（ DFIG）因其具有优良的发电运行性能,在目前的风力发电中得到了广泛地应用。为了研究其不同数学模型在电压跌落故障时的暂态特性,该文以MATLAB／SIMULINK为仿真平台,分别建立了DFIG完整的五阶数学模型及忽略定子磁链暂态变化的三阶模型,在此基础上搭建了相应的风电系统仿真模型,并对风电系统在相同电压跌落幅度时的电磁暂态过程进行了仿真研究。仿真结果表明,DFIG的五阶数学模型在电压跌落时的暂态响应更为清晰和细致,能更精确地表征其在电压跌落时的暂态响应过程。     

变速恒频双馈风力发电机组的逆系统控制研究

为解决矢量控制方法在双馈风力发电机组中存在的对电机参数比较敏感和在扰动下控制不稳定等问题,将逆系统技术应用到双馈感应发电机(DFIG)的控制中.根据输入/输出状态方程得到了逆系统解析表达式,建立了双馈风力发电逆系统闭环控制.在计算机仿真软件Matlab上对该控制系统在电压跌落时和变速恒频时进行了仿真,仿真结果表明逆系统...