基于改进单纯形法和凝结水节流的超超临界机组协调优化

风能、太阳等新能源的规模化并网对电网的安全稳定性造成较大影响。为提高新能源的消纳能力,电网对燃煤机组的运行灵活性、负荷快速响应能力、深度调峰能力等提出了很高的要求。采用先进的控制策略提升协调控制的品质,具有重要的现实意义。基于近年来发展起来的"凝结水节流"快速变负荷方法,采用人工神经网络建立了考虑凝结水节流特性的负荷预测模型及主汽压力预测模型。在此基础上,利用经典优化理论中的改进单纯形法,设计了协调系统智能优化控制策略,编制了实时优化程序。借助1000 MW超超临界机组仿真机开展了详细的优化控制仿真实验,结果表明文中方法可有效提高机组变工况负荷响应的快速性,减少主汽压力波动,提升协调控制品质。     

考虑储能寿命和参与调频服务的风储联合运行优化策略

储能系统与风电场联合运行,不但可跟踪风电场计划出力,还可参与电网的辅助服务。以风储联合运行的总收益最大为目标,考虑储能系统跟踪风电计划出力与参与电网二次调频服务,建立风储联合运行的优化模型。该模型重点考虑了计及不同荷电状态下的储能寿命损耗和储能参与调频时向上调频电量与向下调频电量的平衡。基于实际风电场运行数据设计算例并进行仿真分析,结果表明,考虑储能寿命损耗和储能调频电量水平,不仅可以合理衡量储能参与各项服务所带来的收益,还可以充分发挥储能的作用并提高风储联合的收益。     

Simulated annealing-based optimal wind-thermal coordination scheduling

The rise of environmental protection and the progressive exhaustion of traditional fossil energy sources have increased the interests in integrating wind energy sources into existing power systems. Development of better wind-thermal coordination algorithms is necessary to determine the optimal proportion of wind generator capacity that can be integrated into the system for operating an isolated hybrid power system reliably and efficiently. A stochastic searching technique, which utilises a simulated annealing (SA) approach combined with an efficient constrained dynamic economic dispatch (CDED) method, is developed to coordinate the wind and thermal generation scheduling in isolated power systems with large integration of wind capacity. The SA algorithm is used for the scheduling of the generating units, whereas a direct search method routine carries out the ramp rate CDED when considering wind power generation. Several technique constraints are applied to determine the maximum proportion of wind generator capacity that can be integrated into the system. A constraint satisfaction technique for generating feasible neighbouring solution is also developed to improve the SA solution process. Numerical experiments are included to understand the wind generator capacity in the operating cost analysis and to provide valuable information for both the operational and planning problems     

基于仿射可调鲁棒优化的园区综合能源系统经济调度

新能源和负荷的不确定性给综合能源系统（integrated energy system,IES）运行带来挑战。首先,基于线性形式的能源集线器模型,对园区IES进行了建模。其次,构建了基于仿射可调鲁棒优化的园区IES两阶段经济调度模型,通过该模型可求得机组的启停及基准出力,以满足不考虑可再生能源出力的能量平衡要求,并求得机组的参与因子,使得调度方案对可再生能源出力不确定集下的任意场景均可行。最后,将该模型转化为混合整数线性规划模型（mixed integer linear programming,MILP）进行求解。算例分析结果表明：通过可调鲁棒优化的经济调度方法所求得的调度方案较经典鲁棒优化有更好的经济性与鲁棒性。     

关于频率响应控制未来发展的思考

特高压输电工程逐步推进导致单一元件故障所造成功率失衡数量不断增加,可再生能源大规模接入导致常规机组容量占比持续降低,频率稳定控制攻防两端此消彼长,频率稳定问题凸显;而不断丰富的源网荷侧频率响应控制手段需要更好地协调,以充分发挥其控制效能从而提升频率稳定水平。通过频率响应控制视角下未来电网的结构与形态分析,明确了频率响应控制资源需要精细化管理与控制,指出需要开展动态视角下的频率响应运行调度和频率响应资源集中统一协调控制等理论的研究工作,为频率响应调节资源的规划、计划与调度和多类主体参与频率响应控制提供参考,从而提高系统整体频率响应能力,提升大扰动下的频率稳定抵御能力。     

考虑运行风险的含储能综合能源系统优化调度

为解决综合能源系统（integrated energy system,IES）中供需双侧不确定因素对运行调度带来的风险问题,提出了一种考虑运行风险的含储能IES优化调度模型。在目标函数中,用设备调整费用、失负荷惩罚费用和弃风弃光惩罚费用来量化系统运行风险。在约束条件中,区分了电能和热能的时间尺度差异,并计及储能的时间耦合性,建立了储能多时段耦合约束。然后提出了一种基于Benders分解的算法进行求解。最后通过算例分析了置信水平、储能功率及容量对IES运行费用及运行风险的影响。     

风电机组有功功率集散优化控制系统研究

研究了一种风电机组有功功率集散优化控制策略,并基于此提出一套风电机组有功功率集散优化控制系统开发方案,该系统架设于风电场自动发电控制（automatic generation control,AGC）系统以及风电机组机群能量管理系统（energy management system,EMS）之间,不改变AGC系统与EMS的原有架构,并且可综合考虑风机机群上网电价差异、设备稳定性、发电能力及寿命等因素,以利用上网电价较高、稳定性较好的发电设备为目的,从而实现风电机组有功功率的集散优化控制。     

基于动态自由能磁滞模型的GMM-FBG电流传感器磁滞建模与参数辨识

为解决GMM-FBG电流传感器中存在的磁滞非线性和涡流损失问题,提出了一种耦合涡流损失模型的动态自由能磁滞模型,采用非线性遗传算法对该模型进行参数辨识和优化,提高了模型在工频下对磁滞曲线的预测精度.搭建了 GMM-FBG电流传感器实验平台,利用所建的磁滞模型对传感系统进行建模补偿和实验验证.实验结果表明该模型能够较好地...     

Reliability evaluation of generating systems containing wind power and energy storage

Global environmental concerns associated with conventional energy generation have led to the rapid growth of wind energy in power systems. Many jurisdictions around the world have set high wind penetration targets in their energy generation mix. Wind speed is variable in nature, and power output from a wind farm is not readily controllable. High wind penetration can lead to high-risk levels in power system reliability and stability. In order to maintain the system stability, wind energy dispatch is usually restricted and energy storage is considered to smooth out the fluctuations and improve supply continuity. The benefits from using energy storage are highly dependent on the operating strategies associated with wind and storage in the power system. A simulation technique that can consider wind farm and energy storage operating strategies is presented. Different operating strategies are compared and the resulting benefits are evaluated. The system impacts of energy storage capacity and operating constraints, wind energy dispatch restrictions, wind penetration level and wind farm location on the reliability benefits from energy storage are illustrated.     

A Capacity Improving Scheme in Multi-RSUs Deployed V2I

The communication reliability and system capacity are two of the key performance indicators for Internet of Vehicles (IoV). Existing studies have proposed a variety of technologies to improve reliability and other performance, such as channel selection and power allocation in Vehicle-to-Infrastructure (V2I). However, these researches are mostly applied in a single roadside unit (RSU) scenario without considering inter-cell interference (ICI) of multi-RSUs. In this paper, considering the distribution characteristics of multi-RSUs deployment and corresponding ICI, we propose a reliable uplink transmission scheme to maximize the total capacity and decrease the interference of multi-RSUs (mRSU-DI) in condition of the uplink interruption performance. In the proposed mRSU-DI scheme, ICI is depressed by dynamic channel and power allocation algorithm. A heuristic algorithm based on penalty function is proposed to obtain the optimal power allocation solution of the model. In addition, we realize the scheme in both given conditions of channel state information (CSI) and channel state distribution, respectively. The results show that the proposed scheme can both improve the system capacity and guarantee the reliable transmission in both premises.     

基于持续抽检的电力物资多阶段动态采购模型及系统

针对电力物资集中采购模式中由于采购批量大、合同周期长而导致的不稳定供应问题,提出一种多阶段迭代修正式的电力物资动态采购模型,运用持续质量抽检进行供应商动态调整。首先根据经济订购批量模型确定最佳招标批次、划分标包,并设定多阶段招标模式及供应商评价指标体系;同时依托供应商绩效评价系统,获取历史抽检数据并迭代预测各供应商物资质量,通过建立标包份额动态分配模型动态修正供应商供应量。通过具体案例对模型进行了示例和验证,并对产品质量与供货量的关联性进行了敏感性分析,为采购方有效控制物资质量、供应商提高中标率提供了指导。最后,介绍了项目组开发的一个基于移动物联网的电力物资送检系统,为本文所提的评价模型提供了可行的实施环境。     

QoS-Aware and Resource-Efficient Dynamic Slicing Mechanism for Internet of Things

With the popularization of terminal devices and services in Internet of things (IoT), it will be a challenge to design a network resource allocation method meeting various QoS requirements and effectively using substrate resources. In this paper, a dynamic network slicing mechanism including virtual network (VN) mapping and VN reconfiguration is proposed to provide network slices for services. Firstly, a service priority model is defined to create queue for resource allocation. Then a slice including Virtual Network Function (VNF) placement and routing with optimal cost is generated by VN mapping. Next, considering temporal variations of service resource requirements, the size of network slice is adjusted dynamically to guarantee resource utilization in VN reconfiguration. Additionally, load balancing factors are designed to make traffic balanced. Simulation results show that dynamic slicing mechanism not only saves 22% and 31% cost than static slicing mechanism with extending shortest path (SS_ESP) and dynamic slicing mechanism with embedding single path (DS_ESP), but also maintains high service acceptance rate.     

一种在微网动态经济调度中考虑风电随机性的方法

微网作为大电网的有效补充和建设智能电网的重要实现形式在目前得到了广泛的发展.风电是微网系统中重要的组成部分,以其经济、环保等特性而备受青睐.但是风电对气象条件的依赖性较大,具有间歇性、随机性的特点,因而对于含风电的微网经济调度具有一定的挑战性.本文拟建立考虑风电随机性的微网动态经济调度模型,对风电的随机性通过场景模拟的方法来解决,场景由拉丁超立方（LHS）采样得到,并介绍了基于概率距离的场景消除技术.在该模型的基础上研究了风电随机性对微网经济调度的影响,最终采用GAMS/BARON算法求解了目标函数,通过对算例的分析验证了所提模型的合理性.     

Dynamic phasor and frequency estimator for phasor measurement units

Synchrophasors and frequency estimations play an increasingly important role in power systems. Discrete Fourier transform (DFT) may introduce errors into phasor and frequency estimations under dynamic conditions, such as power oscillation. A dynamic phasor and frequency estimator for phasor measurement units (PMUs) is proposed to improve accuracy by considering dynamic characteristics of power systems expressed as Taylor derivatives. Firstly, phasor estimations of sequence components of diffident data windows are attained via DFT. Secondly Taylor derivatives, expressed by adjacent phasors at different data windows, are employed to improve accuracy of estimations by reassigning estimations with the knowledge of dynamic characteristics. Finally, dynamic characteristics of positive sequence components are applied to estimate the fundamental frequency with less delay compared to a state-of-the-art algorithm, phasor-based synchronised frequency measurement (PSFM). To verify the performance, a set of digital dynamic tests and a power oscillation model using PSCAD/EMTDC are presented. The simulation results show that proposed algorithm can achieve highly accurate estimations of phasor and frequency over a wide range of dynamic conditions. Even though a minor increase in calculation burden is required, this technique provides accurate phasor and frequency estimations without changing the legacy structure of PMU devices. Additionally, it has been found that proposed algorithm really meets the needs of online applications.     

交流变频调速系统仿真建模及谐波特性分析

随着电力电子技术的发展,交流变频调速系统以其强大的优势逐渐取代传统的直流调速传动,其在给人们生产生活带来方便和效率的同时,也造成了电力系统谐波污染加重的问题。因此,设计了一种开环正弦脉宽调制（sinusoidal pulse width modulation,SPWM）控制的交流变频调速系统并搭建仿真模型,实现了对系统中变频器输出电压频率和幅值及电机转速的灵活控制。对系统网侧电压和电流进行了谐波特性分析,结果表明：网侧电压的波形比较理想、畸变很小,而电流波形畸变严重;且随着变频器输出频率的增加,电压波形畸变程度有所加剧,电流畸变程度有所减轻。     

弃风条件下考虑机群电价差异的风电场控制策略

基于风电存在弃风限电以及不同电价的情况,提出一种最大化风电场收益的控制策略。在风电场自动发电控制系统和不同机群能量管理系统之间搭建一套协调控制系统。该协调控制系统基于不同机群的上网电价,考虑机群最大发电能力,将发电指标合理分配给不同机群,在保证机组运行可靠、安全的前提下让电价高的机组优先发电,让电价低的机组满足最小运行负荷,从而实现收益最大化。通过计算不同机群的理论功率,最终得出实际提升的收益。     

计及先进绝热压缩空气储能多能联供特性的微型综合能源系统优化调度模型

先进绝热压缩空气储能（Advanced adiabaticcompressed air energy storage,AA-CAES）是一种清洁的大规模物理储能技术。相对于其他类型的储能技术,AA-CAES技术具有多能流联供的独特特性,这一特性使得其在微型综合能源系统中具有广阔的应用前景。考虑AA-CAES电站的多能联供特性,研究了含AA-CAES电站的微型综合能源系统优化调度策略。介绍了含AA-CAES电站的微型综合能源系统基本构成;基于AA-CAES电站的实际热力学过程,构建AA-CAES电站的冷热电多能流联合调度约束模型;在此基础上,以最小化系统运行成本为目标,建立含AA-CAES电站的微型综合能源系统优化调度模型;最后,采用天津中新生态城的数据进行模型验证。     

OFDMA系统资源优化综述

在正交频分多址(OFDMA)系统中,有效的资源分配可以充分发挥系统性能.目前的资源优化主要分为频谱效率优化与系统能效优化两个方面.频谱效率优化即在给定的总功率下,最大化系统总容量;系统根据信道状态信息,分步对子载波和功率进行分配.根据不同的业务需求,频谱效率优化又细分为仅考虑频谱效率的优化以及考虑用户公平性与复杂通信环境下的优化.系统能效优化是在保证系统总容量的同时,降低系统的总功率消耗.能效优化算法采用了分式规划、约束条件松弛与拉格朗日对偶分解等最优化理论的方法进行资源分配的优化.在加入不同约束的考虑下,能效优化算法分为保证用户公平性、回程线路容量、通信安全等不同的能效优化方案.但是,这两方面的资源优化对不完整信道信息的情况考虑较少,对于多业务的资源分配,未能针对业务多样性进行高效资源优化.另外,资源优化在跨层资源分配上仍有不足.     

Opportunistic WiMAX-GSM coexistence

In future multi-media applications dynamic access to spectral resources will play an important role. However, regulation of spectrum will only change very slowly and spectrum rights holders might not be willing to share their resources without gaining something out of it. Therefore the authors analyse the suitability of WiMAX as an overlay system on GSM where available resources will be auctioned among several competitors. The authors design a cross-layer approach to facilitate dynamic resource allocation. It is demonstrated that, with minor changes of the original WiMAX frame and a small signalling overhead which is currently unused, GSM resources can be allocated efficiently without decreasing system performance. Thus, this adapted WiMAX system used in opportunistic coexistence to GSM offers a suitable alternative to broadband service access.     

Re-defining the reactive power dispatch problem in the context of competitive electricity markets

This study proposes a novel reactive power dispatch model that takes into account both the technical and economical aspects associated with reactive power dispatch in the context of the new operating paradigms in competitive electricity markets. The main objective of the proposed model is to minimise the total amount of dollars paid by the system operator to the generators for providing the required reactive power support. The real power generation is decoupled and assumed fixed during the reactive power dispatch procedures; however, because of the effect of reactive power on real power, a re-schedule in the real power generation is allowed within given limits. The 32-bus CIGRE benchmark system is used to illustrate the proposed reactive power dispatch technique. The developed model is generic in nature and designed to be adopted by system operators in any electricity market structure, as demonstrated by its application to Ontario's grid considering its market rules for reactive power payments.