建设抽水蓄能电站必要性的思考

抽水蓄能电站具有填谷调峰的优良特性。详述了调频、调相、负荷调整、旋转备用、提高电网可靠性的辅助功能以及世界和中国抽水蓄能电站的发展情况。提出我国在火电比重大和建设核电站的电网及"西电动送"受端电网,优先发展抽水蓄能电站,在水电比重较大,但调节性能差的电网,适当配置抽水蓄能电站。抽水蓄能电站一般应修建在负荷中心附近,且有天然湖泊或已建水库处。     

广东抽水蓄能电站功能发挥情况研究

全面回顾了广东抽水蓄能电站的运行历程,重点总结了广州抽水蓄能电站投运20多年来所发挥调峰、调频、调相、事故备用、黑启动等功能的情况以及惠州抽水蓄能电站近5年来的运行情况,并通过对广东电网不同发展阶段典型运行方式分析,研究了系统调度发挥抽水蓄能电站不同功能的运行规律和演变过程。文章可为改善抽水蓄能电站的调度运行管理和后续规划提供重要参考。     

抽水蓄能机组调相压水系统设计与控制策略

鉴于调相压水系统是抽水蓄能机组抽水方向运行和调相工况运行的重要设备,且对抽水蓄能机组安全稳定运行和可靠工况转换起着非常重要的作用。从硬件配置上介绍了调相压水系统的构成和各设备的功能及选型原则,结合蓄能机组典型流程梳理了调相压水系统的控制逻辑,并结合现场实际测试结果验证了流程设计的合理性和科学性,对抽水蓄能电站调相压水系统的设备选型和控制策略研究具有一定的指导意义。     

Prospect of new pumped-storage power station

In this paper, a new type of pumped-storage power station with faster response speed, wider regulation range, and better stability is proposed. The operational flexible of the traditional pumped-storage power station can be improved with variable-speed pumped-storage technology. Combined with chemical energy storage, the failure to achieve second-order response speed and the insufficient safety and reliability of pumped-storage power units could be solved. With the better solar energy and site resources, the integrated performance can be improved by an optical storage system installed in future pumped-storage stations. Through the characteristics analysis of the new type of pumped-storage power station, three types of optimal station locations are proposed, namely, the load concentration area, new energy concentration area, and ultra- high-voltage direct current receiver area. Taking the new pumped-storage power station as an example, the advantages of multi-energy cooperation and joint operation are analyzed. It can be predicted that the frequency and load regulation of the power grid will be more flexible, and the service capacity to the main power grid will be much stronger in the future.     

山东电网建设抽水蓄能电站的必要性

介绍了山东电网电源结构的特点和调峰现状,根据山东电网调峰容量预测和平衡情况,详细分析了抽水蓄能电站在山东电网的作用及经济性。分析结果表明,抽水蓄能电站可以在山东电网的电力平衡中充分发挥作用;建设抽水蓄能电站可增加调峰和备用容量,降低火电单位煤耗,还可作为电网的调频、调相、事故备用、黑启动电源,对电力市场的安全和电网经营起重要作用。因此,山东电网建设抽水蓄能电站是必要的。     

混合式抽水蓄能电站过渡过程研究

为了适应电网发展的需求,具备一定地形地质条件的常规水电站可考虑通过增装蓄能机组扩建成混合式抽水蓄能电站。针对共用引水系统的常规机组和蓄能机组实际运行特点,基于特征线法和瞬变流理论,建立了水力过渡过程计算模型,并结合工程实例模拟了混合式抽水蓄能电站可能发生的多种过渡过程工况,确定了合理的蓄能机组的关闭规律,复核了已建调压室的稳定性。结果表明,通过对新增蓄能机组导叶启闭规律的独立调控,一定程度上可维持混合式抽水蓄能电站输水发电系统的安全稳定,避免增设调节保证设施;蓄能机组导叶关闭时间延长,在降低自身蜗壳末端最大压力的同时,可抑制常规机组甩负荷后的蜗壳末端压力及最大转速上升;对于既有调保措施威胁最大的相继增负荷工况,引用流量较大的常规机组优先增负荷比引用流量较小的蓄能机组优先增负荷引起的调压室最低涌浪值更高,更有利于调压室的稳定运行。     

Influence of two systematic parameters on the geothermal heat pump system operation

In order to match the output capacity of a geothermal heat pump system (GHPS) with the actual load requirement, research has been carried out in finding the influence of two systematic parameters, the water flow rate inside the condenser and the compressor input frequency on the GHPS operation. Experiments are done on a small-scale GHPS at the water flow rate ranging from 0.054 kg/s to 0.174 kg/s and the frequency from 30 Hz to 55 Hz. The analysis of the experimental data reveals the relationships among the compressor frequency, the water flow rate and other important parameters such as coefficient of performance (COP), heat capacity and compressor power input. The conclusions in the paper can serve as some guidance to the load adjustment of GHPS.     

An automatic load shedding scheme including pumped-storage units

An automatic load shedding scheme considering the pumped-storage units at Taiwan Power Company (Taipower) is proposed in this paper. Taipower owns ten pumped-storage units which can be shed with higher priority when operated in pumping mode in order to restore the system frequency. In this way, the amount of customer load required to be shed can be significantly decreased. The system reliability and stability can also be enhanced. In the paper, a load frequency control model is developed. An automatic load shedding scheme that is adaptable to Taipower operation is thus developed. The proposed method has been validated through the utility data and compared with the utility shedding scheme. Test results solidify the feasibility and effectiveness of the proposed method for the applications     

两个系统参数对地热热泵循环的影响

为了解决地热热泵系统输出能量和用户需求能量之间的动态平衡问题，该文对系统的两个主要参数(冷凝器侧水流量和压缩机输入频率)对地热热泵循环特性的影响进行了相应的实验研究。在小型地热热泵系统上进行了变频及变水流量实验研究，频率变化范围为30Hz～55Hz，冷凝器水流量变化范围为0．054kg／s～0．174kg／s；然后，通过对实验数据的分析，发现了系统各参数，如COP值、制热量、压缩机能耗等随频率及水流量的变化规律。该文的结论可以在制定地热热泵系统能量输出的调节策略中起到一定的指导作用。     

Theoretical model for evaluation of variable frequency drive for cooling water pumps in sea water based once through condenser cooling water systems

In sea water based once through cooling water system for power plants, sea water is pumped through the condenser and the return hot water is let back to sea. The cooling water pumps (CWP) in power plants generally operate at constant speed, pumping variable quantities of water depending on the tide level in the sea. The variable flow causes variation in condenser back pressure resulting in changes in the turbine cycle heat rate. If the pump speed is controlled using a variable frequency drive (VFD) to maintain design flow irrespective of the tide level, the CWP power consumption can be reduced compared to the case with constant speed CWP. However, the turbine cycle heat rate benefit that could have accrued at tide levels above the pre defined level (for fixing the CWP head) with constant speed CWP would have to be sacrificed. This paper provides a theoretical model with a typical case study to establish viability of providing VFD for CWPs in power plants with sea water based once through condenser cooling water system.     

四川电力系统迫切需要建设抽水蓄能电站

根据四川电力系统的现状和发展，研究阐述了抽水蓄能电站对电网巨大的机动灵活性，从而带来电网最佳经济效益和社会效益，是解决系统长期存在的调峰调频，缺少备用容量、弃水调峰损失等问题的好办法，是四川电力系统安全经济运行的迫切需要。     

湿法脱硫旁路烟道流场分析

随着烟气脱硫(FGD)在我国火电机组的广泛应用,有关FGD系统对机组正常运行的影响,FGD系统以及安装FGD系统后整个电厂的安全经济运行的研究正日益提上日程。从一些电厂旁路烟道或未装挡板,或装了挡板也常开运行这一现象出发,用计算流体力学(CFD)方法分析了取消挡板前后烟道的流场特征。进行了在挡板开启/关闭的情况下,调节增压风机参数的数值实验;给出了在变负荷情况下,挡板开启的增压风机调节曲线,以达到环保、安全和经济多方面的要求;通过对温度场的考察,发现了安装温度测点的最佳位置,从温度的变化,可以反映烟气的流动情况,避免脱硫效率降低或能耗增加。     

抽水蓄能电站服务电网评价指标体系及方法

中国现行抽水蓄能电站的运营模式要求必须要对其辅助服务功能进行评价。分析了现行抽水蓄能电站辅助服务功能评价现状,建立了评价抽水蓄能电站功能作用的指标体系,并提出辅助服务的贡献率指标,量化了抽水蓄能电站在电网中的辅助服务作用,建立了抽水蓄能电站辅助服务的模糊综合评价方法。     

2010年抽水蓄能电站在华东电网合理规模探讨

根据华东电网电源现状与负荷特性预测,在比较电力系统调峰措施方案的基础上,通过电力电量平衡及调峰容量盈亏分析,论述了华东电网加快建设抽水蓄能电站的必要性;运用电源优化规划模型,对华东电网所需抽水蓄能电站的合理规模进行了分析,提出了2010年华东电网新增抽水蓄能电站装机容量占华东统调电网的合理比例,为华东地区电力系统电力规划提供了参考.     

考虑凝汽器压力的火电厂循泵出口阀启闭规律优化

当火电厂循环冷却水系统中发生水力瞬变时,凝汽器可能出现冷却水失水现象,这将导致凝汽器压力增高,从而影响汽轮机组运行的稳定性及安全性。循泵出口阀启闭规律的优化设定对凝汽器最大失水量能起到一定的控制作用。本文提出水力过渡过程计算结合凝汽器变工况计算的方法来优化设定阀门规律。经应用于300MW汽轮机组实例表明,采用该法确定的最优规律,凝汽器最小过流量从1.991m3/s增加到2.271m3/s,凝汽器最大压力从22.111kPa降低为16.911kPa。这样既能保证循环水系统的水力安全,又考虑了瞬变过程中凝汽器的动态特性,有利于汽轮机组的安全稳定运行。     

计及风电场与负荷惯性响应的电力系统惯性时间常数测量

大量风电接入导致电力系统惯量减少、频率稳定性变差。为评估电力系统频率稳定性,将电力系统的惯性划分为同步发电机、风电场和负荷提供的三种不同类别的惯性,通过摇摆方程建立目标函数,应用粒子群算法求解风电场和同步发电机惯性时间常数,为提高粒子群算法计算结果的稳定性引入绝对中位差算法,在Matlab/Simulink中搭建含有风电场和动态负荷的电力系统仿真模型。仿真计算表明,该方法能够准确测量风电场和同步发电机惯性时间常数。     

Load control of a wind-hydrogen stand-alone power system

A new generation of load controllers enable stand-alone power systems (SAPS) to use one or many standard (grid connected) wind turbines. The controllers use fuzzy logic software algorithms. The strategy is to use the control loads to balance the flow of active power in the system and hence control system frequency. The dynamic supply of reactive power by a synchronous compensator maintains the system voltage within the limits specified in EN50160. The resistive controller loads produce a certain amount of heat that is exchanged down to the end user (hot water). It was decided to investigate the implementation of a hydrogen subsystem into the SAPS that can work in parallel with the Distributed Intelligent Load Controller (DILC). The hydrogen subsystem can then function as energy storage on long-term basis and an active load controller on short-term basis.     

可变进气道发动机性能试验及分析研究

针对1台单缸电控4气门发动机进行了可变进气的改进设计,使发动机进气道的流量系数、涡流比、滚流比等流动特性,随着不同的运行工况而变化,从而达到优化发动机中低负荷性能的目的。对可变进气发动机进行的台架性能及排放试验结果表明:随着节气门开度从25%上升到75%,发动机功率提高了4.37%~2.56%,扭矩提高了4.21%~2.56%,燃油消耗率降低了4.89%~2.66%。在中低负荷时,可变进气可以优化发动机的动力和经济性能,但随着负荷的增大,改善的幅度减小。同时,可变进气可使HC、CO排放降低4%~9%,而NOx排放有所上升。     

Frequency control in micro-grid power system combined with electrolyzer system and fuzzy PI controller

The widespread use of various kinds of distributed power sources would impact the quality of the power supply within a micro-grid power system, causing many control problems. This paper focuses on the stability of micro-grid operation and discusses the control techniques of combining a micro-turbine with the fuel cell and electrolyzer hybrid system to expand the micro-grid system's ability to solve power quality issues resulting from frequency fluctuations. The paper examines the feasibility of fuel cell and electrolyzer hybrid system control, especially dynamic control of an electrolyzer system, to secure a real power balance and enhance the operational capability of load frequency control. The proposed control and monitoring system can be considered to be a means of power quality control, both to improve the frequency fluctuations caused by random power fluctuations on the generation and load sides and to relax tie-line power flow fluctuations caused by frequency fluctuations in the interconnected micro-grid power system.     

Optimization of cold-end system of thermal power plants based on entropy generation minimization

Cold-end systems are heat sinks of thermal power cycles, which have an essential effect on the overall performance of thermal power plants. To enhance the efficiency of thermal power plants, multi-pressure condensers have been applied in some large-capacity thermal power plants. However, little attention has been paid to the optimization of the cold-end system with multi-pressure condensers which have multiple parameters to be identified. Therefore, the design optimization methods of cold-end systems with single- and multi-pressure condensers are developed based on the entropy generation rate, and the genetic algorithm (GA) is used to optimize multiple parameters. Multiple parameters, including heat transfer area of multi-pressure condensers, steam distribution in condensers, and cooling water mass flow rate, are optimized while considering detailed entropy generation rate of the cold-end systems. The results show that the entropy generation rate of the multi-pressure cold-end system is less than that of the single-pressure cold-end system when the total condenser area is constant. Moreover, the economic performance can be improved with the adoption of the multi-pressure cold-end system. When compared with the single-pressure cold-end system, the excess revenues gained by using dual- and quadruple-pressure cold-end systems are 575 and 580 k$/a, respectively.