利用制氢系统消纳风电弃风的制氢容量配置方法

在分析风电制氢系统结构和运行特性的基础上,提出一种利用制氢系统消纳风电弃风的制氢容量配置方法。采用区间估计方法建立风电年弃风电力统计模型,以经济收益最大为目标,运用区间优化理论确定制氢系统最优容量配置区间;通过建立多属性决策模型,确定制氢系统最优电解槽配置方案。分别以东北某30 MW风电场和100 MW风电场群为例进行对比分析,结果表明风电场群共建制氢系统的方案其经济性更为显著。进一步量化分析电解槽电耗量、H2市场价格、弃风利用率和风电机组年利用小时数等关键因素对制氢系统配置容量的影响。     

考虑制氢效率提升的风电制氢系统优化控制策略

通过分析电解制氢效率与制氢功率的关系，提出一种基于分段模糊控制电解槽阵列效率提升的策略，基于大规模风-氢耦合系统应用场景，建立考虑风电制氢效率的风电制氢系统优化调度模型，并采用人工蜂群算法求解最优制氢功率。仿真结果表明，所提出的控制策略不仅可保证电解槽的安全运行，同时能提高电解槽的制氢效率，为电解制氢系统在电力系统中的大规模应用提供理论依据。最后，在此基础上，加入电解槽阵列的模块化优化策略，使建立的分段模糊控制器能够统筹安全性、经济性、能效性，以期为氢能在电力系统中的大规模应用提供理论依据。     

新能源发电工程储能系统容量/功率优化配置

新能源风、光发电工程中配置一定容量的储能系统,可以显著提高新能源发电的消纳水平。储能系统的容量/功率的优化配置可最大程度提高储能系统利用效率和经济性,同时将新能源风电、光伏的弃电率降低到设定的目标值。提出以全生命周期内储能系统净现值最大为目标,综合考虑储能系统全生命周期内投资、运维成本、购电成本、售电收入、充放电效率、荷电状态、储能电池寿命、弃电率等多种因素的储能系统容量/功率优化配置方法,并以青海某工程1 030 MW光伏阵列和250 MW风电场的运行数据为例,计算得到该新能源风电、光伏发电工程中净现值最大的储能系统容量/功率配置,使整个储能系统获得最优的经济性。     

基于自适应功率阈值的电网辅助光伏制氢控制策略及容量优化配置北大核心CSCD

针对光伏变功率制氢无法维持在高效工作区间,造成欠经济运行的问题,文章提出一种兼顾效率和灵活性的光伏制氢控制策略及容量优化配置方法。首先以电解水制氢功率与效率模型为基础,提出基于自适应功率阈值的电网辅助光伏制氢控制策略,通过电网辅助吸收光伏多余电量或补充缺额电量,以电网年净出力为零为约束,计算出制氢设备的自适应功率阈值,确定制氢系统高效经济的运行方案,使制氢工作模式更灵活地响应光伏出力。最后建立电网辅助光伏制氢成本及收益模型,以系统净收益为目标对制氢系统进行容量优化配置。通过仿真验证,所提制氢控制策略及容量配置方法提高了光伏制氢变功率运行的产出效率,在低成本投资下,实现较高的产能收益,系统经济性显著提高。     

基于蚁狮算法的风电集群储能容量配置优化方法

随着风电渗透率提高,风电并网对电网安全稳定运行影响更加显著。风电配备储能可有效改善风电出力波动性和不确定性,增强可调度性。该文建立以风电集群联合储能系统售电收益最高为优化目标的模型,采用蚁狮算法算法进行求解,得到风电集群功率备用、储能功率和容量最优配置方案,对比蚁狮算法、遗传算法和粒子群算法优化结果,分析储能电池单位成本和寿命对优化结果影响。最后以中国东北某风电集群作为算例,验证了所提算法与模型的有效性。     

基于动态电价风光电制氢容量配置优化

为降低风光发电弃电率及提高上网风光电品质,提出加入储能单元的风光电耦合制氢系统。以能量管理算法和容量最优化算法为核心,同时考虑动态电价的影响,以单位制氢成本最小为目标,对储能单元和制氢单元容量进行优化配置。算例针对500 MW的风电场和100 MW的光伏电站,计算最优容量配置下的最小单位制氢成本,并将该成本与煤气化制氢成本比较,分析风光电制氢的可行性。最后通过敏感性分析,指出提高风光电制氢经济效益的关键因素。     

波动率优于国网标准的风电场储能容量经济优化配置

基于某风电场出力的实际数据,从不同时间尺度上分析了该风电场的功率波动特性。考虑了风电场弃风成本、储能惩罚成本、储能投资和运行成本,通过3种成本间的制约关系,构建了储能容量经济优化计算模型;采用滑动时间窗口算法并引入平抑修正系数,制定出波动率优于国网标准的期望参考功率。采用改进粒子群算法,针对某含储能风电电网进行了储能容量优化配置,求解出最优储能容量和最小经济总成本,对比了不同储能容量配置策略下的经济性,并引入了波动率评估因子对平抑效果进行了量化分析。仿真结果表明,该优化配置方案能够将风电出力波动率限制在20%以内,优于国网标准,且经济性最好,具有较好的应用前景。     

绿氢制备经济性趋势分析

氢能被认为是未来能源系统的重要组成部分,只有通过可再生能源电力制备的绿氢才是清洁的能源产品。在绿氢替代传统化石燃料制氢的过程中,经济性是重要的制约因素。在分析预测可再生能源发电成本和绿电获取成本的基础上,分别计算使用电网绿电连续制备绿氢和使用可再生能源发电间歇制氢的成本,结合氢气储运场景,研究绿氢制备经济性的发展趋势。研究结果表明,采用电网绿电配合碱性电解槽连续制备绿氢,是当前最经济可靠的绿氢制备方式。如采用专用绿电制氢,2030年前陆上风电+碱性电解槽制氢成本最低,专用光伏发电+碱性电解槽制氢将在2030年后成为经济性最好的专用绿电制氢方式,而专用光伏发电+PEM电解槽制氢的成本始终最高。采用专用陆上风电和光伏+碱性电解槽制备氢气的经济性,在2025年后将超越天然气制氢+CCS,在2040年后会逐步超越煤制氢+CCS。电力成本是驱动未来绿氢制备成本下降的主要因素,电解槽成本下降对绿氢成本下降影响较小。建议要加强先进绿电制氢技术研发,拓宽可再生能源发电终端消纳的途径;同时要加强对国际绿氢制备前沿技术的跟踪。     

基于合作博弈的风-光-电氢微网容量配置

当风电场、光伏电站、电氢混合储能系统分属不同的投资者时,微网容量配置存在微网整体运行最优与各投资者自身运行最优的矛盾,同时风、光出力的不确定性也会影响容量配置。针对上述问题,提出一种考虑风、光不确定性,基于合作博弈的风-光-电氢微网容量配置方法。首先,依据有序聚类和K-均值聚类提取出风-光-负荷典型月场景;其次综合考虑影响微网运行的因素,构建基于不同投资者的经济模型,在典型月场景下,分析完全合作博弈、部分合作博弈、非合作博弈模式下各投资者与联盟的收益关系;最后,以月净收益最高为优化目标,利用改进灰狼优化算法配置投资者装机容量,并基于shapley值分配合作联盟投资者收益。根据算例结果和关键参数灵敏度分析可知,微网在完全合作博弈模式下兼顾经济性与低碳性,且各投资者利益分配合理;电价、风光补贴价格的波动对各投资者影响不同。     

考虑风储多维运行边界的调峰资源优化配置模型

近年来,风储联合发电系统取得了一定的发展,但在网络约束下的储能系统储放范围与风电渗透率之间存在着制约的关系,导致原有调峰资源的配置方案会对储能系统的储放空间及运行效率产生一定的影响。为解决该问题,文章引入风储联合系统接入配网后的多维运行边界并将其转化为调峰资源优化配置过程中的约束条件,建立综合考虑风储容量与调峰资源经济性的优化配置模型并进行求解。仿真算例验证结果表明,文章提出的考虑风储多维运行边界下调峰优化配置模型可实现风电与储能利用最大化及调峰资源配置经济性最优。     

Optimal sizing of wind-hydrogen system considering hydrogen demand and trading modes

In order to make full use of renewable energy and improve the utilization of wind power, a new joint optimization scheme of the wind-hydrogen system coupled with transmission project is proposed in this paper, in which wind power is reasonably allocated for grid integration and for hydrogen production. Aiming at maximize the annul wind-hydrogen system benefit, the optimal sizes of wind power transmission project and hydrogen system are obtained under different hydrogen production modes, hydrogen trading modes and hydrogen demand levels. In addition, the penalty cost of wind curtailment and hydrogen supply shortage and the system environmental benefits are taken into account. Results show: during the long-term of insufficient of wind power, it is better to produce hydrogen using wind power and grid-assisted power to avoid hydrogen supply shortage; considering the future increase of hydrogen demand, the optimal supply number of hydrogen refueling stations in the wind-hydrogen system is two. Also, the low utilization of fuel cells means that the benefit from regeneration cannot offset the high cost, which leads to the abnegation of fuel cells in the wind-hydrogen system.     

Size optimization and economic analysis of a coupled wind-hydrogen system with curtailment decisions

In order to maximize the return on equity (ROE) of wind-hydrogen system investors, take full advantage of the wind power as well as smooth the wind power output of a wind farm, an optimal sizing model of a coupled wind-hydrogen system (CWHS) is established considering the requirements of wind power grid-connection technology. The fluctuating cost of wind power is calculated by an “equal-kWh following load” method and the chance-constrained programming is introduced to deal with the uncertainty generated by the wind power. The optimal capacity of each unit for a CWHS, including the wind power transmission project, electrolyser, compressor and so on, is acquired and the economic analysis is evaluated under comprehensive aspects, e.g. wind curtailment decisions, hydrogen prices, the correlations between wind power output and system load, and the fluctuation degrees of wind power generation. The simulation is established by the realistic historical data from a wind farm in Fujian, China. When the confidence level is 92%, the capacity of electrolysers increases with the increase of the hydrogen price when it is larger than the equivalent value 4.34 €/kg. In addition, the smaller the correlation between wind power output and load and the bigger the volatility index of wind power output, the less the smoothing benefit of the CWHS, where the smaller capacity of the transmission project and bigger capacities of electrolysers and compressors are required.     

基于链式分配策略的风氢耦合系统设计与控制

针对风力发电“弃风”电量耦合制氢问题,提出一种基于链式分配策略的风氢耦合系统。首先建立能表征弃风电量与质子交换膜电解槽主要特性的风氢耦合拓扑电路结构,围绕高降压比交错Buck变换器及其控制方法构建风氢耦合系统,并提出多堆质子交换膜电解槽风氢耦合系统链式功率分配策略。最后通过算例仿真验证该系统可提升弃风利用率和系统可靠性,可有效解决弃风电量水电解制氢耦合控制与功率分配问题。     

Transient electrolyser response in a renewable-regenerative energy system

In a renewable-regenerative electrolyser/fuel-cell system, the electrolyser performs the critical function of converting excess renewable input energy into hydrogen. Electrolyser operation on time scales and duty cycles that are relevant to common renewable resources (e.g., wind and solar) were probed using an experimental residential-scale system. Experimental results indicate that the electrolyser's transient characteristics have a significant impact on the efficiency of the conversion process. Two key findings are presented. First, a reduction in electrolyser hydrogen production, relative to steady-state levels, is observed due to the thermal transient and time-dependent decay in current draw. These time-dependent aspects are typically not addressed in the theoretical models proposed to date for electrolyser operation. Second, it was found that maintaining a minimum electrolyser current is critical to avoid performance decline induced by dynamic operation. The requirement for a minimum operating current (and therefore minimum power input) places constraints on the common operating methodology for renewable-regenerative systems.     

Influence of wind turbine power curve and electrolyzer operating temperature on hydrogen production in wind-hydrogen systems

Current simulation tools used to analyze, design and size wind-hydrogen hybrid systems, have several common characteristics: all use manufacturer wind turbine power curve (obtained from UNE 61400-12) and always consider electrolyzer operating in nominal conditions (not taking into account the influence of thermal inertia and operating temperature in hydrogen production). This article analyzes the influence of these parameters. To do this, a mathematical wind turbine model, that represents the manufacturer power curve to the real behaviour of the equipment in a location, and a dynamic electrolyzer model are developed and validated. Additionally, hydrogen production in a wind-hydrogen system operating in “wind-balance” mode (adjusting electricity production and demand at every time step) is analyzed. Considering the input data used, it is demonstrated that current simulation tools present significant errors in calculations. When using the manufacturer wind turbine power curve: the electric energy produced by the wind turbine, and the annual hydrogen production in a wind-hydrogen system are overestimated by 25% and 33.6%, respectively, when they are compared with simulation results using mathematical models that better represent the real behaviour of the equipments. Besides, considering electrolyzer operating temperature constant and equal to nominal, hydrogen production is overestimated by 3%, when compared with the hydrogen production using a dynamic electrolyzer model.     

Resource potential for wind-hydrogen power in Ukraine

The paper provides an assessment of the current wind energy potential in Ukraine, and discusses developmental prospects for wind-hydrogen power generation in the country. Hydrogen utilization is a highly promising option for Ukraine's energy system, environment, and business. In Ukraine, an optimal way towards clean zero-carbon energy production is through the development of the wind-hydrogen sector. In order to make it possible, the energy potential of industrial hydrogen production and use has to be studied thoroughly.Ukraine possesses huge resources for wind energy supply. At the beginning of 2020, the total installed capacity of Ukrainian wind farms was 1.17 GW. Wind power generation in Ukraine has significant advantages in comparison to the use of traditional sources such as thermal and nuclear energy.In this work, an assessment of the wind resource potential in Ukraine is made via the geographical approach suggested by the authors, and according to the «Methodical guidelines for the assessment of average annual power generation by a wind turbine based on the long-term wind speed observation data». The paper analyses the long-term dynamics of average annual wind speed at 40 Ukrainian weather stations that provide valid data. The parameter for the vertical wind profile model is calculated based on the data reanalysis for 10 m and 50 m altitudes. The capacity factor (CF) for modern wind turbine generators is determined. The CF spatial distribution for an average 3 MW wind turbine and the power generation potential for the wind power plants across the territory of Ukraine are mapped.Based on the wind energy potential assessment, the equivalent possible production of water electrolysis-derived green hydrogen is estimated. The potential average annual production of green hydrogen across the territory of Ukraine is mapped.It is concluded that Ukraine can potentially establish wind power plants with a total capacity of 688 GW on its territory. The average annual electricity production of this system is supposed to reach up to 2174 bln kWh. Thus, it can provide an average annual production of 483 billion Nm³ (43 million tons) of green hydrogen by electrolysis. The social efficiency of investments in wind-hydrogen electricity is presented.     

Stand-alone operation of an alkaline water electrolyser fed by wind and photovoltaic systems

Over the last few years, hydrogen technologies have established themselves as key enablers in the medium and long-term development of a new energy model that offers greater sustainability and independence than the present-day one. In this respect, the integration of water electrolysis with renewable energy-based systems can play an important part in the large-scale production of sustainable hydrogen. This paper reports on the complete experimental characterisation of a 1 Nm³ h⁻¹ alkaline water electrolyser located in the Public University of Navarre (UPNa). Specifically, a study was made of the electrical performance, hydrogen production rate, purity of the gases generated and energy efficiency, for a range of operating currents (40–120 A), temperatures (35–65 °C) and pressures (5–25 bar). Additionally, an experimental study was conducted on the electrolyser operation under conditions that are characteristic of a stand-alone wind power and PV-based renewable energy system, installed at the UPNa. The results obtained for the wind power and PV emulations showed that the electrolyser performed correctly, with regard to balance of plant and its principal electrochemical characteristics. Furthermore, the mean energy efficiency of the electrolyser was 77.7% for the wind power emulation, and 78.6% for the PV emulation on a day with stable irradiance, and 78.1% on a day with highly variable irradiance (day with scattered clouds).     

Simulation-based sensitivity analysis of an on-site hydrogen production unit in Hungary

This article examines the additional profit that can be achieved with the integrated operation of an on-site electrolyser, a hydrogen tank, a photovoltaic system, and a wind power plant based on Hungarian data from 2019. The results of the optimisation show that the system economically reduces the volatility of weather-dependent renewable production, so there is a promising demand-side management potential in coordination. We found that the operating profit is highest in April at EUR 19,416, 18,932 in July, and lowest at EUR 17,075 in January. The production curve of photovoltaic capacities is better matched to fuel demand, so increasing the share of solar energy results in lower balancing activity but higher profits. Increasing the size of the hydrogen storage and electrolyser, with constant hydrogen demand and prices, will cause a convergent increase in profits, however above a 10 kg storage capacity or 350 kW electrolyser capacity there is no substantial profit increase. In the case of the economically optimal asset size, there is a slight competition between the electricity market and the hydrogen distribution activity. The choice between the two activities depends on current electricity and hydrogen prices and the cost of unmet hydrogen demand.     

风氢耦合系统能量管理策略研究

针对风力机出力的波动性和并网弃风问题,采用风力机/电解槽/燃料电池/超级电容的风氢耦合发电系统及其能量管理控制策略。针对风氢耦合发电系统的12种运行模式,提出一种能量管理控制策略,确保在各个控制单元的作用下,能量协调流动于各个子单元间。能量管理控制策略不仅使风氢耦合发电系统出力可控,而且平抑了直流母线电压波动,平滑了上网功率。通过Matlab/Simulink软件进行仿真研究,验证了风氢耦合发电系统的能量管理控制策略的有效性,提高了风电消纳能力。     

Electrolysers as a load management mechanism for power systems with wind power and zero-carbon thermal power plant

For an isolated power system the deployment of a large stock of electrolysers is investigated as a means for increasing the penetrations of wind power plant and zero-carbon thermal power plant. Consideration is given to the sizing and utilization of an electrolyser stock for three electrolyser implementation cases and three operational strategies, installed capacity ranges of 20–100% for wind power and 10–35% for zero-carbon thermal power plant (as proportions of the power system’s maximum electrical demand) were investigated. Relative to wind-hydrogen alone, hydrogen yields are substantially increased especially on low-wind days. The average load placed on fossil-fuelled power plant is substantially decreased (while achieving a virtually flat load profile) and the carbon intensity of electricity can be reduced to values of <0.1 kg CO₂/kWh_e. The trade-offs between the carbon intensity of the electricity delivered, the carbon intensity of the hydrogen produced and the daily hydrogen yield are explored. For example (on the variable wind day for Strategy C with respective wind power and zero-carbon thermal power penetrations of 100% and 35%), if the carbon intensity of hydrogen is relaxed from 0 to 3 kg CO₂/kg H₂, the hydrogen yield can be increased from 435 tonnes to 1115 tonnes (which is the energy equivalent of 120% of consumer demand for electricity on that day). The findings suggest that the deployment of electrolysers on both the supply and demand-side of the power system can contribute nationally-significant amounts of zero or low-carbon hydrogen without exceeding the power system’s current maximum system demand.