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101.
新疆作为重要的送端电网,频率稳定问题尤为突出,对推动"疆电外送"能源战略造成重大影响,送端电网特别是弱系统送端电网频率稳定问题值得深入研究。首先从理论上分析了反调现象产生的机理以及反调对解列区域电网的影响,提出了发电机负荷突变开始时刻屏蔽干扰抑制功率反调策略,并搭建了仿真模型,最后以新疆区域电网解列为例,仿真验证了施加抑制策略后的效果,所论述的抑制措施在调速系统参数整定中值得借鉴。  相似文献   
102.
电流互感器在电力行业中被广泛应用于电流的测量,也有部分场合用来给监测装置供电,但很少电流互感器既用来测量电流值,又当作电源来使用。基于自具电源的智能无线温度传感器采用开合式结构设计,首次将电流互感器既当作电源用,又用来测量线路的电流值。此外传感器还带有无线通信、测温、带电指示、故障指示和故障录波等功能。  相似文献   
103.
针对如何在"三集五大"体系下建设电网运行支撑系统。并且做到节约投资,提高效益,更好地为大运行服务开展应用实践和技术研究。在介绍调度自动化系统和配电网自动化系统现状的基础上,分析两套系统的相同点和主要区别,阐述调配一体自动化系统建设的必要性、可行性。针对具体的运行支撑系统的结构进行对比分析,给出建设调配一体自动化系统的方法。实践证明调配一体自动化系统应用是可行的,最后描述了调配一体自动化系统应用案例的实际效果。  相似文献   
104.
研究了电网频率变化对水轮发电机组气隙磁场过饱和、发电机中性点接地装置、阻尼绕组温升及铁心损耗的影响。提出限制发电机运行方式、接地方式等应对策略,保证水轮发电机组能在频率不稳定的电网中可靠运行,为海外工程水轮发电机组选型及运行提供参考。  相似文献   
105.
Wireless communication applications for smart grids are a novel trend in renewable energy solutions. However, the problem of interference in the channel must be considered. The GPRS/EGPRS standards could be used to transmit the reference signals to the wind power system. A Direct Torque Control technique for a DFIG was proposed to testing the reactive power and the electromagnetic torque step changes according to the grid conditions using the wireless references signals. A Fuzzy-tuned PI controller was included to optimize the calculation of its proportional and the integral gains. Simulations were done in Matlab/Simulink to evaluate the behavior of the control technique via GPRS-CS1, EGPRS-MCS1 and EGPRS-MCS5 standards. The total harmonic distortion for the stator currents injected to the grid is also evaluated.  相似文献   
106.
智能电网元件引入配电网和市场系统,对电网需求侧管理提出了新的挑战和机遇。智能电网国家实验室LAB+i已经拥有必要的基础设施进行智能电网的案例研究,其中包括电力需求侧管理。介绍了哥伦比亚国立大学的应用案例,在LAB+i平台实施基于3种需求响应技术的自动化管理系统,能够为校区每个建筑找到最佳负荷曲线。  相似文献   
107.
A study of the Australian National Electricity Market shows that using battery storage in the Australian national electricity grid reduces CO2 emissions by providing further flexibility for the operation of conventional generators and also by decreasing the amount of unused renewable energy. Interestingly, energy storage is more efficient at reducing carbon emissions in the context of higher carbon and/or fuel prices. In addition to reducing emissions, battery storage can decrease the cost of delivered energy.  相似文献   
108.
Boosting the concept of smart cities for implementing an intelligent management of traffic congestion while reducing cybersecurity concerns will not only be more efficient for reducing traffic congestion but also more resilient to cyber incidents. In this paper we proposed a framework that can act as a generalized firewall and work interactively with several critical infrastructures in a smart city to protect the respective operations from a variety of cyber threats. The objective is to develop several steps for a comprehensive traffic management framework in smart cities that facilitates the cooperation among drivers and between drivers and the traffic management authority. The transformative nature of the proposed study supports its applications to a variety of networked critical infrastructures, including electricity, gas, water, rails, and telecommunications, as they intend to respond effectively to a wide range of weather- or human-related disruptions. The contributions of this paper include: Improving the traffic management performance in urban transportation systems, assessing and mitigating the cybersecurity risk in urban traffic management, and facilitating efficient and cyber-secure traffic management in metropolitan areas; Developing and testing an interactive simulation platform for evaluating the traffic management performance under various traffic conditions; Validating and demonstrating the applications in a practical urban transportation system; Disseminating the proposed study results to a wide range of concerned audiences via user-group meetings, detailed education forums, and a close collaboration with the local traffic management authority.  相似文献   
109.
Game theory has provided a practical tool to model players' strategic behavior in electricity markets, particularly as the world moves towards a more competitive market. A game theoretic approach can be used to find the clearing electricity price in a retail electricity market with a high penetration of small and mid-size renewable suppliers.  相似文献   
110.
This paper presents a novel approach to deal with the regulation of the dc-link capacitor voltages and ac-side currents in a grid-connected five-level diode-clamped converter. Due to the controllability problems of this topology, guaranteeing a solid current control and, mainly, a correct dc-link voltage sharing, represents a complex technical challenge. With the purpose of coping with it, an averaged model that describes the system dynamics at both sides of the converter is presented, assuming that a modulation strategy is integrated in the system to generate the switching sequence. In order to derive the proposed model, no restriction concerning the use of only the three nearest vectors to the desired voltage reference is taken into account. Then, several changes of variables are carried out in the model equations to obtain control input decoupling for control purposes, while reducing the complexity of the model as well. Finally, the voltage and current controllers are designed separately using different control inputs in a straightforward way. Neither auxiliary hardware nor complicated mathematical calculations are required to achieve the control objectives. The effectiveness and good performance of the system under the proposed control approach are validated by simulation results, suggesting that the five-level diode-clamped converter can be a solid solution as an interfacing system connected to the utility grid for, e.g., industrial drives or renewable energy applications.  相似文献   
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