计及实时交通特征的电动公交车备用率与充电桩联合优化

为了提高电动公交车及充电站总投资和运营的经济性,需综合考虑公交车和充电桩的购置成本以及充电成本。以道路特征、实时交通特征、环境温度为主要影响因素,计算电动公交车的行驶时间和能耗;在满足公交车运营基本需求和保证车内温度的前提下,以日公交车购置成本、日充电桩建造成本、日充电成本之和最小为目标进行优化,建立电动公交车备用率与充电桩的联合优化模型,并采用改进的离散型自适应粒子群优化算法进行计算,得到公交车和充电桩的最优购置方案以及各季节和全年的日均投资及运营成本。以某公交线路上电动公交车年内多种运营条件为算例,验证所建优化模型的正确性。

浅谈如何提高锅炉油枪备用率

锅炉燃烧不稳或启、停炉过程中备用的油枪不能正常投入，引起锅炉灭火或拖延机组的启、停时间，通过分析近几年来油枪不能正常投入使用的原因，采用相应的对策，提高了锅炉油枪的备用率。

考虑大规模光伏接入的机组检修中等备用率法的改进

发电机组检修计划是一个带多约束条件的多目标优化问题,通常有2类:可靠性目标函数以及经济费用目标函数。目前采用最广泛的目标函数是等备用法、等备用率法以及等风险度法等可靠性目标函数。随着大规模光伏电站接入电力系统,传统的机组检修规划方法越来越显现其局限性,在考虑大规模光伏接入电力系统的基础上,对传统的等备用率法进行改进,建立了改进等备用率法。采用该方法进行机组检修规划,不仅运算速度快,检修规划更加的合理,也更加适应大容量光伏接入的系统。

“双碳”目标下抽水蓄能提升系统保供能力的技术经济性研究

本工作通过时序仿真模拟,对抽水蓄能在典型省级电网中的保供技术经济性进行量化分析。首先,根据典型省级电网未来电力规划数据,计算得出该省级电网2025年与2030年全年电力系统运行情况,结果表明系统在全年部分时段处于供电紧平衡状态,系统备用率不足10%,充裕性和安全性面临巨大挑战。其次,选取抽水蓄能与火电机组两种灵活性调节电源,对比分析新增两种调节电源下系统供电可靠性改善情况和两种方案的量化经济性,结果表明,以2030年该省级电网模拟结果为例,配置1200万千瓦抽水蓄能和火电机组均能够将该省级电网系统全年备用率提升10%以上,解决系统备用率不足问题,提升系统保供能力。考虑系统碳排放变化所产生的环境成本,抽水蓄能改善系统供电水平的年度综合成本低于同等水平下的火电机组,同时能够对新能源消纳水平的促进和碳排放水平的降低起到积极作用。最后,比较分析了抽水蓄能与锂离子电池储能对于提升系统供电可靠性的综合经济性,结果表明抽水蓄能对于改善系统供电可靠性和充裕性等方面的综合经济性优势显著。

电力系统备用容量模型

发电设备合理备用容量和备用率问题是电力系统中的一个特殊问题。本文在等效持续负荷曲线概念的基础上,利用曲线拟合的思想,得出了负荷与时间的函数关系式,进一步求得合理备用容量和备用率。

计及备用容量及考虑禁止区间的含风-蓄电力系统经济调度

风电出力具有随机性和反调峰性,接入电网后会对其稳定运行产生负面影响。抽水蓄能电站能够依据负荷需求储存多余风能或释放电能,平抑风电出力波动,减少弃风量。由于火电厂组件的物理限制,发电机在其运行区间的某些范围内会使轴承振动放大。因此应该在含风-蓄系统的电力系统经济调度模型中,设置火电机组出力的禁止区间。通过最小日负荷率和备用容量率对给定的负荷等级进行划分,确定抽水蓄能电站的运行状态;建立解决风-蓄系统接入含禁止区间电力系统的经济调度问题的0-1混合整数非线性规划模型,该模型中设置含有禁止区间的备用容量约束,采用matlab编写BNB20函数对6火电机组、1风场和1抽水蓄电站系统进行仿真,研究禁止区间和备用容量对经济调度的影响,仿真结果证明了该方法行之有效。

发电机组检修计划的模拟植物生长算法

建立了以系统在一个检修周期内各周的净备用率与整个检修周期的平均净备用率之差绝对值之和最小为目标的发电机组检修计划优化模型,并同时保证各周的净备用率不低于允许的最小值。通过采用全部待检修机组检修启动时段的组合为决策变量,给出了基于模拟植物生长算法的求解方法。针对各种约束条件的不同特点,分别给出了相应的处理方法。最后用算例对模型及算法进行了验证,得到了比采用现有的等备用率模型及启发式算法更优的发电机组检修计划,显示了所提出方法的正确性和有效性。

西气东输管道压气站设置

压气站的设置在大型输气管道中是非常关键的技术。介绍了压气站的机组备用形式、不同压比的输送方案比选、影响压气站设置的因素等。通过四种压气站输送方案的经济对比 ,确定了压气站的数量设置和机组的选择范围。对压气站适应“照付不议”

水火电机组年度检修计划安排的实用优化模型

为减少机组检修计划安排的工作量,提高发电系统的可靠性水平,提出了以系统最小备用率最大及机组检修计划调整事项最少为目标的机组检修计划优化模型。所提模型为能够采用CPLEX等商业软件求解的、数学上为线性混合整数优化模型。仿真结果表明,采用该模型有助于保障适度的备用率水平、减少检修计划事项的调整数量及调度中心与发电厂的协调工作量,且计算速度能够满足实际工程应用要求。

矿山法海底交通隧道废水排水系统调研与思考

随着我国矿山法施工的海底交通隧道(简称海底隧道)的增加,其废水排水系统也愈来愈显得重要。为了使该系统更加安全、可靠、经济,笔者在认真研读青岛胶州湾海底隧道、厦门翔安海底隧道相关资料基础上,进行了现场调研。在此基础上,对其设计思路及运营现状进行了对比与分析,包括海底隧道废水量确定、废水泵流量及台数的确定,海底隧道对废水泵选型、安装方式、水泵管材材质要求,扬水管数量确定以及对废水泵提升方案讨论,海底隧道供水管爆管理念、爆管控制技术及废水池大小的确定等内容;最后,从如何提高废水排水系统的性价比角度,提出看法和思考。

大发热量电气设备室暖通设计

变频器、SVG控制柜以及励磁柜等电气设备间空间较小且散热量较大,设备柜体温度过高,易引起高温报警,甚至导致设备故障率高。文章介绍了此类设备间的暖通设计方法,并对每种方法的优缺点进行分析。由于电气设备的重要性,需在节约设备投资的同时,增加房间的空调备用率。

腈纶装置变压器最佳运行工况分析

腈纶装置设计中选择变压器的主要依据为变压器的负荷率、效率，功率因数及备用率。通过对变压器负荷率与效率关系的定量分析，提出变压器负荷率与效率的最佳关系，并阐述了实际生产过程中变压器增容时应考虑的相关因素。

少人值守水厂疫情防控期间人员配置及应急管理

对于少人值守水厂疫情防控期间最低人员配置及应急管理的主要影响因素,疫情期间首先应做好水厂安全运行管理措施,保障封闭运行期间最少人员配置的同时,水厂生产能力不降低,生产设备正常稳定运行,安全优质供水。这就要水厂安全运行管理过程中,要加强各方面的管理,采取有效的措施解决各种问题,不断加强设备的技术研究,不断创新改进完善,从而进一步促进水厂高效能的安全运作和水厂科学技术现代化发展。基于此本文分析了影响少人值守水厂疫情防控期间最低人员配置及应急管理的主要因素及建议。

景电工程泵站多台出水液控蝶阀的集中控制及其自动化改进

总结了景电工程泵站出水液控蝶阀与机组的联动以及泵站自动化控制的研制、改造成果,针对单台液控蝶阀在实际运行中存在的一些问题,根据景电工程泵站自动化控制的需要,结合工程设备特性及实际,将机组的出水液控蝶阀由单台各自独立控制改进为多台集中控制,并在此基础上又进行了改进和完善,从而更进一步满足了泵站自动化控制的要求。

Energy Efficient Power Allocation for Relay-Aided D2D Communications in 5G Networks

As one of the key technologies for the fifth generation(5G) wireless networks,device-to-device(D2D) communications allow user equipment(UE) in close proximity to communicate with each other directly.Forwarded by a relay,the relay-aided D2D(RA-D2D) communications can not only be applied to communications in much longer distance but also achieve a high quality of service(Qo S) .In this paper,we first propose a two-layer system model allowing RA-D2 D links to underlay traditional cellular uplinks.Then we maximize the energy efficiency of the RA-D2 D link while satisfying the minimum data-rate of the cellular link.The optimal transmit power at both D2 D transmitter and D2 D relay sides is obtained by transforming the nonlinear fractional programming into a nonlinear parameter programming.Simulation results show that our proposed power allocation method is more energy efficient than the existing works,and the proposed RA-D2 D scheme outperformed direct D2 D scheme when the distance between two D2 D users is longer.

Preparation of solid medium for use in separation with gas-solid fluidized beds

The highly-efficient dry separation technique using a gas-solid fluidized bed is very beneficial for increasing coal grade and optimizing the utilization of coal resources.The size distribution of the solid medium(e.g.,magnetite powder) used in this technique is one of key factors that influences fluidization and separation performance.It is,therefore,urgent to prepare medium in a way that operates at low cost and high efficiency.Grinding experiments were performed using a planetary ball mill equipped with a frequency converter.The effect of fed mass,rotation frequency of the mill,grinding time and the ball-size ratio on grinding performance was investigated.The grinding parameters were optimized by numerical calculations using Artificial Neural Network(ANN) in Matlab.A regression equation for predicting the yield of the desired product(i.e.,0.3～0.15 mm magnetite powder) is proposed.The maximum yield of 0.3～0.15 mm particles was 47.24%.This lays a foundation for the industrial-scale production of the solid medium required for separation with a magnetite-powder fluidized bed.

Coordination of multiple grid-connected inverters for harmonic compensation

For multiple grid-connected inverters with active filter function,it makes sense to regulate every unit to output maximum active power from photovoltaic arrays,as well as eliminate the harmonic due to the non-linear loads connected to the electric networks.Naturally,a centralized control coordination strategy was proposed for the purpose of high facility utilization,good harmonic compensation ability and unwanted overcompensation condition.Based on a vector decoupling control scheme and generalized instantaneous reactive power theory,the solution was to allocate the harmonic eliminating task for every inverter according to the instantaneous power margin of each.The grid current always keeps sinusoidal in spite of non-linear load change and output active power change for any inverter.The simulation results validate the efficacy of the proposed coordination strategy.

Utilization of Data Communication according to the IEC61850 Standard for Nuclear Power Plant Electrical Equipment Testing

This paper deals with an integration of directly measured electrical parameters with data acquired by data communication from protections and terminals into an advanced monitoring system. Based on the periodic test, the authors of this paper present the possibility of an extended evaluation and more accurate analysis of transient and failure events. For periodical testing, as implemented during the commissioning of power plants in the Czech Republic, a monitoring system of electrical equipment has been used, to record the courses of important electrical parameters and thus, proving the proper functioning of complex technological systems in various operation modes. Data from monitoring system were used to prove the successful results of the test or as a base data for further analysis of failures. The monitoring system has proved itself as a very useful device also when recording unexpected failure events, the cause of which was very quickly and accurately detected by the follow-up analysis. Initially, only the voltage and current data from measuring transformers, analogue transducers and contact relays were used as input data for the monitoring system. After the implementation of new digital protection technology and controlling terminals with inner data recorder, the data from digital devices could be also utilized for the monitoring system.

Application of swarm intelligence algorithm on PFSP

With today＇s global economic downturn and the increasingly fierce market competition, manufacturing enterprises must guarantee the efficient operation of production system, in order to get ahead in the competition, scheduling reasonable flow shop production systems can improve productivity and equipment utilization rate, reduce production costs. So the production system of flow shop scheduling problem has become one of the core problems ofmanufactaring enterprises the use of more and more.