风-光-火-蓄联合系统两阶段优化调度

由于间歇性能源出力具有不确定性,该文利用抽水蓄能容量大、响应速度快的优势,建立风-光-火-蓄两阶段动态调度模型。长时间尺度以总成本最低为目标,综合考量系统运行成本、SO₂、NO_X、PM排放量、弃风弃光量惩罚,来优化可控电源出力。短时间尺度以长时间尺度为基准,基于模型预测控制原理滚动求解出力增量,使抽蓄机组有功出力偏差最小,以增强调度的平滑性。最后根据东北某地区抽蓄机组实际数据及改进的IEEE-30节点系统仿真验证了该文所提模型的有效性,以此来降低系统的污染物排放水平,提升系统对风电、光伏的消纳能力。     

Counter-Rotating Type Pump-Turbine Unit Stabilizing Momentarily Fluctuating Power from Renewable Energy Resources

It is difficult for renewable energy resources to provide constant power with excellent quality for the grid system. This serial research proposes a power stabilization system with a pumped storage to guarantee power quality and capacity, while the outputs from the energy resources are at unstable and/or fluctuating conditions. The power stabilization system with a counter-rotating type pump-turbine unit was prepared and operated at the pumping and the turbine modes. The unit composed of the tandem impellers/runners connected to the inner and the outer armatures of the unique motor/generator. The experiments have verified that this type pump-turbine unit is reasonably effective to stabilize momentarily/instantaneously the fluctuating power from the renewable energy resources.     

Flexible HVDC Transformer for Next Generation Renewable Energy Industry

The growing demand on non-fossil fuel energy has escalated the desire for mega-scale renewable energy power generation, which can no longer be satisfied solely by relying on onshore renewable energy power plants. Outcomes from a recent project funded by the Sixth European Union Framework Programme （FP6）, Project ＂Upwind＂ concluded that larger offshore wind turbines （i.e., 〉 10 MW） are feasible and cost effective. It will be beneficial for such future large scale renewable energy power generators （i.e., large offshore turbines） and plant （i.e., large offshore wind farms） to have a dedicated high efficiency, robust, flexible and low cost power collection, transmission and distribution technology. Proposed in this paper is a compact and effective hybrid HVDC （high voltage direct current） transformer that allows realisation of a highly robust and financially rewarding next generation multi-terminal HVDC system for future offshore renewable energy power plant. This concept, potentially, allows the elimination or minimisation of the need for a centralised local offshore HVDC platform or substation in each wind farm, solar farm, or tidal farm. This paper discusses the study outcome of the proposed hybrid HVDC transformer and the application of a multi-terminal HVDC system in the renewable energy industry, compared to the existing HVAC and VSC （voltage source converters） type HVDC systems.     

风电场中抽水蓄能电站的优化配置

为解决电力系统接入风电容量超过一定比例后引起的调峰及弃风问题,改善风电场功率输出特性,可采用与风电场配套建设抽水蓄能电站的模式。在建立风电场及抽水蓄能电站运行模型的基础上,以风电—抽水蓄能电站经济效益为目标,采用一种新的自适应遗传算法对风电—抽水蓄能电站的最佳容量配比进行求解。通过对一实际算例的仿真,表明配置适当容量的抽水蓄能电站可提高风电场的综合效益。     

资源分散型水力蓄能UPS/UBS集成电源

论述了国际通信电源及新型分布式电源设备的发展概况,介绍了美国Kahua农场可再生能源储存及试验设备场中的风力提水蓄能电站和水力蓄能UPS电源,并建立了资源分散型水力蓄能UPS／UBS集成电源的简单化设计概念。其运行经验表明：水力蓄能UPS／UBS电源对提高可再生能源供电系统的通信电源的可靠性具有重要意义。     

基于关闭煤矿沉陷区—地下硐室群的抽水蓄能电站构建与利用

关闭煤矿具有建造高水头抽水蓄能电站的天然拓扑结构,利用关闭煤矿建设抽水蓄能电站是储能方式的新探索,也是关闭煤矿资源利用的新方式。以常规抽水蓄能电站主要工程结构为蓝本,结合淮南矿区关闭的潘一矿工程地质条件,提出了淮南矿区沉陷区—地下硐室群抽水蓄能电站的构建模型。该模型主要由关闭煤矿采煤沉陷区(上水库)、地下硐室群(下水库)、煤矿主井中布置的压力管道(引水)、地下厂房组成。根据动能计算,淮南矿区关闭煤矿UPHS电站适宜建设小型抽水蓄能电站,装机规模约50MW,满足附近光伏电站调峰需求,废弃煤矿UPHS电站和光伏电站之间的“水光互补”可行。研究成果对于促进清洁能源发展具有重要意义。     

偏差电量考核下风光储混合发电商的市场均衡博弈研究

为了更直观地分析风光储混合发电商对市场均衡博弈结果和市场力的影响,在偏差电量考核衡量风光储混合发电出力随机波动性的基础上,综合考虑各发电商的出力限制和储能系统的运行约束,建立以风光储混合发电商和传统发电商收益最大化为目标的市场均衡博弈模型,调用CPLEX软件求解利用非线性互补函数处理得到的混合整数规划模型,并对比分析了风光储混合发电商作为价格接受者和影响者参与电力市场竞争对均衡博弈电价和投标出力的影响。结果表明,风光储混合发电商参与电力市场竞争可抑制传统发电商的市场力,对电价有显著的"削峰填谷"作用;当风光储混合发电商作为价格影响者时,对电价的影响会减弱,但其收益有所增加。     

Advanced Reactive Power Control at Individual Residences to Smooth Energy Loss Fluctuation for a Clustered Grid-Interconnected PV System

Reactive power control can control voltage within the proper range from the power network side or from the distribution generation （PV （photovoltaic）） side. Reactive power control from the power network side is simpler because little controlled object apparatus, such as STATCOM, is required. However, it is difficult to optimize the individual voltages of residential consumers because few data have been obtained by the power network side as compared with the power generation side. Energy loss at each residence with PV is different due to the difference in the grid-interconnection condition, such as distribution line impedance when the same operating voltage is set at all residences. Therefore, in this paper, the authors propose an advanced reactive power control method for residential PV systems in order to optimally control the voltage at individual residences so as to minimize energy loss fluctuation. The effectiveness of the proposed reactive power control is demonstrated by numerical simulation.     

Examination for Experimental Verification of Improvement of Power Quality in Distribution System by PCS

In the future, the power quality will decrease by the introduction of a lot of renewable energy sources. The topic of this research is a new method of operation of PCS （power conditioning systems） in the future distribution system. The purpose of this research is development of PCS with a function of improvement of the distribution system. Therefore, the authors propose a method of the power quality improvement of the distribution system by PCS. In addition, the authors construct the control logic to use in PCS The control logic suggests adding harmonic restraint function to conventional control. These were verified by simulation and an experiment. As the results, we confirmed that basic operation of PCS being carried out, harmonics were restrained, and power quality had improved.     

电力系统中抽水蓄能电站调峰作用的研究

探讨核电、风电等清洁能源大规模接入电网后带来的电力系统调峰问题,研究抽水蓄能电站的调峰作用。通过对2020年全国各区域电网电源结构、负荷特性、调峰能力等数据预期进行综合分析,计算出核电、风电机组接入电网后应参与调峰的容量,得出需配套建设抽蓄电站的比例。为今后电力系统的规划建设提供理论依据。     

Contribution of pumped hydro storage to integration of wind power in Kenya: An optimal control approach

This paper investigates the benefit of optimally integrating wind power in Kenya with pumped hydro storage. The approach includes development of an optimal control strategy to deploy paired wind and pumped hydro storage resources, for the Lake Turkana Wind Power project. The stochastic model, which maximizes expected revenue over the planning horizon, is developed taking into the consideration the structure and running of the Kenya electricity market. The 300 MW Lake Turkana Wind Power wind farm is simulated using wind speed data from Marsabit, which is in close proximity to the Lake Turkana region. From the simulation of the wind farm, we find that the daily pattern exhibited by the wind speeds, does not match the average daily load pattern. Pumped hydro storage reduces the systems total power output shortage by 46%. This approach to operation could alleviate the significant economic burden of the take-or-pay purchase agreement that led to the removal of financial backing of the project by the World Bank. The use of pumped hydro storage in conjunction with the wind farm is also found to increase the expected daily revenue of the wind farm by over ten thousand dollars.     

国外抽水蓄能电站发展概况及相关启示

日本是全球抽水蓄能电站装机容量最大、装机比例最高的国家,韩国、西班牙、法国、德国、意大利等国家的抽水蓄能电站装机比例也均接近或者超过5％。日本的抽水蓄能电站已逐步发展成为电力系统的管理工具,韩国将其用于满足调峰填谷、事故备用、提高电网运行效益,西班牙利用抽水蓄能电站独有的填谷功能进一步促进风电的发展．德国消纳大量风电的主要措施之一就是配置较高比例的抽水蓄能电站。抽水蓄能电站的规模配置主要与地区经济发达程度、区域负荷特性、电源结构、互联系统调峰支援能力等有关,建设条件、建设成本和系统其他调峰手段的经济性也会影响到抽水蓄能电站的建设规模。我国正步人抽水蓄能电站快速发展期,应将其纳入电力中长期发展规划．按照区域电网进行统一配置,并将抽水蓄能电站提供的各项功能纳入系统辅助服务补偿范畴。     

Performance analysis of various hybrid renewable energy systems using battery,hydrogen, and pumped hydro‐based storage units

The aim of this research is to analyze the techno‐economic performance of hybrid renewable energy system (HRES) using batteries, pumped hydro‐based, and hydrogen‐based storage units at Sharurah, Saudi Arabia. The simulations and optimization process are carried out for nine HRES scenarios to determine the optimum sizes of components for each scenario. The optimal sizing of components for each HRES scenario is determined based on the net present cost (NPC) optimization criterion. All of the nine optimized HRES scenarios are then evaluated based on NPC, levelized cost of energy, payback period, CO₂ emissions, excess electricity, and renewable energy fraction. The simulation results show that the photovoltaic (PV)‐diesel‐battery scenario is economically the most viable system with the NPC of US$2.70 million and levelized cost of energy of US$0.178/kWh. Conversely, PV‐diesel‐fuel cell system is proved to be economically the least feasible system. Moreover, the wind‐diesel‐fuel cell is the most economical scenario in the hydrogen‐based storage category. PV‐wind‐diesel‐pumped hydro scenario has the highest renewable energy fraction of 89.8%. PV‐wind‐diesel‐pumped hydro scenario is the most environment‐friendly system, with an 89% reduction in CO₂ emissions compared with the base‐case diesel only scenario. Overall, the systems with battery and pumped hydro storage options have shown better techno‐economic performance compared with the systems with hydrogen‐based storage.     

基于改进模型预测控制的“大机小网”下火电-光伏-抽水蓄能优化调度

光伏大规模接入加剧了"大机小网"电网的结构性问题,导致传统单断面优化调度难以实现最优运行。提出了一种基于改进模型预测控制(MPC)的多时间尺度火电-光伏-抽水蓄能联合优化调度模型。即对于日前优化调度,在系统运行成本中引入了光伏未消纳量和火电污染物排放量形成多目标函数;对于日内滚动优化,以跟踪日前计划值为目标,考虑了光伏出力极限场景调节能力约束与抽水蓄能机组启停速率约束,并采用自适应调节预测时域与控制时域的MPC方法改进了传统MPC。海南省某区域电网的实际运行验证了该综合模型的有效性。     

风电-抽水蓄能联合运行系统的模拟研究

构建了一个含风电—抽水蓄能联合运行系统的小型模拟电网,并对其拟定了一个风电—抽水蓄能联合运行方案;然后在最大化利用风电的目标下,建立了该方案的经济运行计算分析模型,经对该联合运行系统与普通风电系统的比较计算分析,验证了本模拟方案和计算模型的正确性;同时证明风电—抽水蓄能联合运行系统是最大化开发利用风能资源的有效途径,具有可观的经济效益和社会效益。     

Defect Detection in Raw Si Substrates Using Transmission Polarimetry

Inline characterization for fabrication of silicon wafer PV （photovoltaic） devices may be used to optimize device efficiencies, reduce their performance variance, and their cost of production. In this article, the frozen in strain from a variety of extended defects in silicon is shown to effect the polarization of light transmitted through a silicon substrate due to the photo-elastic effect. Transmission polarimetry on pre-fabricated silicon substrates may be used for identification of extended defects in the materials using a polarization analysis instrument. Instrumentation is proposed for detection of defects in raw silicon wafers for applications like raw silicon wafer sorting, scanning silicon bricks, and inline inspection prior to solar cell metallization. Such analysis may assist with gettering of silicon solar cells, may be implemented in the sorting and rejection procedures in PV device fabrication, and in general shows advantages for detection of defects in silicon wafer solar cell materials and devices.     

Analysis of the Clean Development Mechanism Considering the Environmental Co-benefits of Reducing Air Pollutants in China

An electricity generation planning model of the six major Chinese power grids was developed based on the General Algebraic Modeling System to evaluate and analyze the CDM （clean development mechanism）, including consideration of the environmental co-benefits of reductions in air pollutants （SO~, NO~ and particulate matter） achieved by advanced electricity generation technologies incorporating CCS （carbon capture and storage）. An objective function was developed that included revenue from sales of electric power, total system cost, the cost of CO2 transport and storage, and emissions reduction co-benefits for SOx, NO~, and particulate matter. The objective function was minimized using an optimization model. We also developed a method for evaluating and analyzing the potential for transferring advanced power generation technologies into the Chinese power system through the CDM. We found that： （1） thermal power generation is predominant in the Chinese electricity system and will remain so for a long time; （2） advanced thermal plants are being installed as a result of the CDM, which contribute to decreasing emissions of CO2 and other air pollutants; and （3） CCS projects have significant potential to reduce substantial and sustained CO2 emissions from the Chinese power and industrial sectors.     

基于风电消纳的多类型储能系统联合经济调度

为使电力系统尽可能提高风电接纳能力,建立了基于风电消纳的实时失调成本模型,考虑到安全性、环保性,分别构建了基于风电-火电调度总成本模型和基于风电-火电-联合储能系统调度总成本模型,并采用HS-PSO混合算法求解调度总成本模型。算例仿真结果表明,抽水蓄能电站、蓄电池和超级电容器混合储能系统在增加经济效益、提高风电接纳能力方面优势明显;同时验证了储能系统容量与弃风率的关系,为含风电并网运行的系统经济调度提供了依据。     

Analysis of Short Circuit Faults in a System Fed by Wind Turbine

Short circuit and ground failures that are quite common in power transmission lines are investigated. These failures are designed considering a system that is supplied by this wind system, and analyses are interpreted. In the study, a system is set up and it is fed by the wind turbine. Furthermore, the mathematical model of wind turbine and generator is prepared and the results obtained from the simulation are evaluated. The short circuit and ground fault analyzes were performed separately for each of the three phases. ATP （alternative transient program）-EMTP （electromagnetic transients program） program is used in the analysis and the results obtained were found to be quite compatible.     

Simulation Analysis for Massive Deployment of Variable Renewables Employing an Optimal Power Generation Mix Model

This paper develops a high time-resolution optimal power generation mix model in its time resolution of 10 minutes on 365 days by linear programming technique. The model allows us to analyse the massive deployment of photovoltaic system and wind power generation in power system explicitly considering those short-term output variation. PV （photovoltaic） and wind output are estimated, employing meteorological database. Simulation results reveal that variable fluctuation derived from a high penetration level of those renewables is controlled by quick load following operation of natural gas combined cycle power plant, pumped-storage hydro power, stationary NAS （sodium and sulfur） battery and the output suppression control of PV and wind. It additionally turns out that the operational configuration of those technologies for the renewable variability differs significantly depending on those renewable output variations in each season and solving the seasonal electricity imbalance as well as the daily imbalance is important if variable renewables are massively deployed.