Research on Regulation Method of Energy Storage System Based on Multi-Stage Robust Optimization

To address the scheduling problem involving energy storage systems and uncertain energy,we propose a method based on multi-stage robust optimization.This approach aims to regulate the energy storage system by using a multi-stage robust optimal control method,which helps overcome the limitations of traditional methods in terms of time scale.The goal is to effectively utilize the energy storage power station system to address issues caused by unpredictable variations in environmental energy and fluctuating load throughout the day.To achieve this,a mathematical model is constructed to represent uncertain energy sources such as photovoltaic and wind power.The generalized Benders Decomposition method is then employed to solve the multi-stage objective optimization problem.By decomposing the problem into a series of sub-objectives,the system scale is effectively reduced,and the algorithm’s convergence ability is improved.Compared with other algorithms,the multi-stage robust optimization model has better economy and convergence ability and can be used to guide the power dispatching of uncertain energy and energy storage systems.

Sizing of Energy Storage Systems for Output Smoothing of Renewable Energy Systems

光伏、风力发电等可再生能源（renewable energysources，RESs）具有随机性、间歇性等特点。为了抑制RESs输出波动对电网的不利影响，提出了用于平滑RESs发电系统功率输出的储能系统（energy storage system，ESS）容量优化确定方法。利用离散傅里叶变换（discrete Fouriertransform，DFT）对RESs输出功率进行频谱分析，基于频谱分析结果，考虑ESS充放电效率、荷电状态（stateofcharge，soc）及RESs发电系统目标功率输出波动率的约束，确定所需ESS最小容量。采用美国华盛顿州实际观测风速数据及日本东北电力公司风电场接入电网20rnin有功功率波动规范（最大波动率为10％），在一风力发电系统中对该方法进行了验证。算例结果表明采用该方法能够以较小的容量将风机输出最大波动率由61．7％降到9．9％。

Analysis on Output Power for Multi-direction Piezoelectric Vibration Energy Harvester

To predict the performance of multi-direction piezoelectric vibration energy harvester,an equation for calculating its output power is obtained based on elastic mechanics theory and piezoelectricity theory.Experiments are performed to verify theoretical analysis.When the excitation direction is along Y direction,a maximal output power about 0.139 mW can be harvested at a resistive load of 65kΩ and an excitation frequency of 136 Hz.Theoretical analysis agrees well with experimental results.Furthermore,the performance of multi-direction vibration energy harvester is experimentally tested.The results show that the multi-direction vibration energy harvester can harvest perfect energy as the excitation direction changes in XY plane,YZ plane,XZ plane and body diagonal plane of the harvester.

Dynamic design of a nonlinear energy sink with NiTiNOL-steel wire ropes based on nonlinear output frequency response functions

A novel vibration isolation device called the nonlinear energy sink(NES)with NiTiNOL-steel wire ropes(NiTi-ST)is applied to a whole-spacecraft system.The NiTi-ST is used to describe the damping of the NES,which is coupled with the modified Bouc-Wen model of hysteresis.The NES with NiTi-ST vibration reduction principle uses the irreversibility of targeted energy transfer(TET)to concentrate the energy locally on the nonlinear oscillator,and then dissipates it through damping in the NES with NiTi-ST.The generalized vibration transmissibility,obtained by the root mean square treatment of the harmonic response of the nonlinear output frequency response functions(NOFRFs),is first used as the evaluation index to analyze the whole-spacecraft system in the future.An optimization analysis of the impact of system responses is performed using different parameters of NES with NiTi-ST based on the transmissibility of NOFRFs.Finally,the effects of vibration suppression by varying the parameters of NiTi-ST are analyzed from the perspective of energy absorption.The results indicate that NES with NiTi-ST can reduce excessive vibration of the whole-spacecraft system,without changing its natural frequency.Moreover,the NES with NiTi-ST can be directly used in practical engineering applications.

The Influences of Energy Price Variation on the Prices of Other Industries: A Study Based on Input-Output Price Model

Energy has laid material foundation for human society during its development. Meanwhile, any change of price in the energy industry may influence social production and people’s life at all levels via an input-output mechanism under which the change related to energy is surely transmitted to other industries. The price change thus incurred in all industries may adversely affect the realization of macroeconomic objective-maintaining prices at a stable level. It is, therefore, needed to conduct an empirical research related to the impact of price change in energy industry on that in other industries. According to the data coming from “China’s 2015 Input-Output Extension Table (42 Departments)” and four hypothetical basis, this article focuses on four energy sectors and analyzes how deeply the price change of them, by use of input-output model, affects that of other industrial products under five conditions where each of their price rises by 10% individually or simultaneously, and why such an influence occurs. The results show that the price rising of the energies in question leads to an upward growth in the prices of other industrial products, especially when their prices go up simultaneously. Besides, the price increase in the four energy sectors doesn’t influence other industries in an accumulation form but actually leads to a rollback in some of other industries. It is recommended to adopt diversified pricing strategies for different energy products, thus maximizing the value of each specific energy, and meanwhile achieving the goals of energy consumption reduction and price equilibrium.

Assessing Asian Economies Renewable Energy Consumption Efficiency Using DEA with Undesirable Output

Along with vast non-fossil potential and significant expertise,there is a question of whether Asian nations are attaining efficient consumption and exploitation of renewable resources.From this perspective,the paper aims to evaluate the efficiency of 14 potential Asia countries in renewable energy consumption during the six-year periods(2014-2019).In analyzing the performance of the renewable energy sector,the data envelopment analysis(DEA)with an undesirable output model approach has been widely utilized to measure the efficiency of peer units compared with the best practice frontier.We consider four inputs and two outputs to a DEA-based efficiency model.Labor force,total energy consumption,share of renewable energy,and total renewable energy capacity are inputs.The outputs consist of CO_(2)emissions as an undesirable output and gross domestic product as a desirable output.The results show that United Arab Emirates,Saudi Arabia,Japan,and South Korea consistently outperform in the evaluation,achieving perfect efficiency scores during the research period.Uzbekistan is found to have the lowest average efficiency of renewable energy utilization.

Energy Giant Expands Gas Output to Meet Growing Demand for Cleaner Fuel

China National Petroleum Corporation(CNPC),Asia’s biggest oil and gas producer,will increase its investment in natural gas exploration and production,pipeline construction and gas sales in the coming decade,betting big on the country’s thirst for the clean fuel.The stateowned company,which currently allocates 70

Improved Blind Multiuser Detection Algorithm Based on Minimum Output Energy

Based on minimum output energy,an improved blind multiuser detection algorithm is proposed by the use of Hopfield neural network.Compared with traditional algorithms,the proposed algorithm does not need the circuit for constraints.The resources are greatly saved and the complexity is reduced as well.The simulation results show that the performance of the improved algorithm is similar to that of the optimal multiuser detection algorithm which is not suitable for the mobile station.Compared with the traditional gradient blind multiuser detection algorithm,the convergence speed of the improved algorithm is quickened.

Robust Input-Output Energy Decoupling for Uncertain Singular Systems

This paper addresses the robust input-output energy decoupling problem for uncertain singular systems in which all parameter matrices except E exist as time-varying uncertainties. By means of linear matrix inequalities (LMIs), sufficient conditions are derived for the existence of linear state feedback and input transformation control laws, such that the resulting closed-loop uncertain singular system is generalized quadratically stable and the energy of every input controls mainly the energy of a corresponding output, and influences the energy of other outputs as weakly as possible. Keywords Uncertain singular systems - generalized quadratical stability - input-output energy decoupling - linear matrix inequality (LMI) Xin-Zhuang Dong graduated from the Institute of Information Engineering of People’s Liberation Army, China, in 1994. She received the M. S. degree from the Institute of Electronic Technology of People’s Liberation Army, in 1998 and the Ph.D. degree from Northeastern University, China, in 2004. She is currently a post-doctoral fellow at the Key Laboratory of Systems and Control, CAS.Her research interests include singular and nonlinear systems, especially the control of singular systems such as H ∞ control, passive control and dissipative control. Qing-Ling Zhang received the Ph.D. degree from Northeastern University, China, in 1995. He is currently a professor with the Institute of Systems Science, Northeastern University. His research interests include singular systems, fuzzy systems, decentralized control, and H 2/H ∞ control.

新能源发电系统控制技术研究

随着经济社会发展,人们用电需求在不断增长,需要将有限的电能资源进行合理利用,找寻新的发电技术和途径,新能源电力技术及控制技术需要得到新的发展。在发电、输电、配电及用电环节中,电力机制发挥着极为重要的作用,能够组建起电能生产与消费的一体化环节。可以运用发电装置将自然界中的可再生能源转变成为电能,用户可以通过输电系统获得电能,给日常生活提供能量供应。传统发电方式难以大规模存储电能,需要控制电能输出方式。新能源发电与传统发电方式存在较大的差异性,新能源的发电输出功率是可控的。该文主要叙述新能源电力系统运行的基本特点,并说明电力系统的主要控制技术及控制策略,为后续新能源电力工程的顺利发展奠定强有力基础。

考虑风光不确定性的综合能源系统容量-成本两阶段规划优化研究

针对综合能源系统规划面临可再生能源波动性强、出力不确定性等问题,文章提出了一种考虑风光不确定性的综合能源系统容量-成本两阶段规划优化方法。首先,运用拉丁超立方抽样生成基础风、光场景集,并基于改进的k-means算法进行场景削减;其次,以运行成本最低、碳减排最优、污染物减排最优构建多目标优化模型;最后,提出系统容量-成本两阶段规划优化求解策略,并选取南方某商业园区进行规划仿真。仿真结果表明,文章所构建的综合能源系统两阶段规划模型能够在保证系统经济性的同时兼顾环保性,并满足用户多种用能需求。

基于能量模型的临界导通模式Boost变换器软开关方法

在变换器高频化发展的趋势中,功率器件的软开关实现对变换效率的影响更加突出。无辅助电路的临界导通工作模式下,Boost变换器主开关管在特定增益下无法实现软开关。为此,该文提出一种能量模型及相应的软开关实现方法。首先,建立死区前后储能元件能量变化的数学模型。然后,结合死区起止时刻的能量平衡方程,研究软开关无法实现的电路机理。在此基础上,考虑开关管输出电容非线性特征,提出软开关实现方法,避免了复杂谐振过程的时域精确建模,提高软开关实现的准确性。最后,搭建500W实验样机进行实验,结果表明,相较于对谐振过程建模的传统时域模型,所提方法将实际开通电压降低47%,使峰值变换效率提升0.4%,进而验证了其有效性。

面向火电运行灵活性的钢球磨煤机制粉系统控制优化研究

针对双进双出钢球磨煤机制粉系统变出力过程风粉温度波动幅度大、瞬时磨煤出力偏差大等问题,提出考虑热一次风风温前馈和变出力过程料位差压设定值优化的控制策略。以BBD4360型钢球磨煤机为对象开展机理建模和瞬态扰动试验研究,建立并验证钢球磨煤机内料位差压、出口风粉温度等关键参数计算模型。基于磨煤机动态模型研究获得原有及优化后的控制策略对磨煤机出口风粉温度、磨煤出力和制粉单耗的影响规律。研究结果表明:在制粉系统变出力过程中,优化后的控制策略可降低磨煤机出口风粉温度偏差2℃以上,制粉系统磨煤出力累积偏差降低50%以上,制粉单耗降低5%以上,综合提升了制粉系统的关键参数控制效果。钢球磨煤机制粉系统优化控制策略有利于缓解机组调峰过程中由于燃料量供给偏差引起的气温、气压偏差大等问题,保障了燃煤发电机组的运行灵活性和高效性。

计及氢能高效利用和热电灵活输出的综合能源系统源荷灵活运行策略

为进一步发挥氢能高效利用优势,构建绿色低碳能源系统,提出一种计及氢能高效利用和热电联产灵活输出的综合能源系统源荷灵活运行策略。首先,对源侧供能模型进行两方面改进:一是引入含风电制氢、燃气混氢、多能用氢和储氢的氢能利用模型,并考虑到电解水和甲烷化反应过程中的热量散失情况,引入热量回收装置,构建计及热量回收的氢能高效利用模型;二是针对常规热电联产灵活性不足的问题,构建含电锅炉和有机朗肯循环的热电灵活输出模型,以解耦常规热电联产“以热定电”和“以电定热”限制。其次,在荷侧引入含可转移、可削减和可平移的电、热柔性负荷,以缓解电、热负荷峰谷差,并与源侧相结合,形成源荷灵活运行模型。最后,综合考虑阶梯型碳交易成本、设备运行维护成本、弃风成本以及购能成本,建立综合能源系统源荷灵活优化运行模型。采用CPLEX求解器对所提综合能源系统源荷灵活运行模型进行求解,并设置不同场景进行对比。结果表明,相比常规氢能利用模型,考虑所提计及热量回收的氢能高效利用模型时,系统的总成本、碳排放量分别降低了1.92%、4.22%,并且引入热电联产改进模型后,其总成本、碳排放量可进一步降低4.08%、7.32%,实现系统低碳、经济和灵活运行。

基于SWIPT的无小区大规模MIMO-NOMA系统能量效率研究

无小区大规模多输入多输出(Multiple-Input Multiple-Output,MIMO)与非正交多址接入(Non-Orthogonal Multiple Access,NOMA)都是未来6G的使能技术。无线携能通信(Simultaneous Wireless Information and Power Transfer,SWIPT)技术在进行信息解码的同时收集能量,与无小区大规模MIMO-NOMA优势互补。文中基于SWIPT研究无小区大规模MIMO-NOMA系统中的能量效率问题,通过联合优化功率分配系数和SWIPT的时隙切换(Time Switching,TS)系数,提高系统的能量效率。为了最大化能量效率,采用布谷鸟算法设计功率分配系数。考虑一种特殊情况,将所有终端的TS系数设置相同,进而推导了最佳TS系数的封闭表达式。仿真结果表明,相较于几种已有方案,文中提出的优化方案可以显著提升系统的能量效率。

水电高占比下风电接入对系统稳定性影响

随着绿色清洁高效能源基地的构建,以水电为主体的水风互补成为我国西南能源开发的重要特征。为研究在典型水电系统中接入风电对系统稳定性带来的影响,首先,针对水风互补系统以转矩分析法分析了风电接入对系统频率和功角稳定性的影响,并通过算例和Prony分析验证了风速与风电渗透率对系统稳定性的影响。结果表明,风电的接入在一定程度上可以削弱传统水电系统的超低频振荡,而风电接入互联送端系统会导致区域等值惯量的下降,进而使系统区域间低频振荡风险加剧。其次,考虑风电的接入会诱发区域间低频振荡,在风电系统中引入风电的附加综合虚拟惯性与阻尼控制。算例与Prony分析验证了该控制策略能有效提高系统稳定性。最后,在区域间大规模风电接入场景下,利用改进的鲸鱼算法对风电的附加控制器参数进行了优化;结果表明,参数的整定有效提高了系统的频率以及功角稳定性。

基于光谱合束的双波长输出Nd:YAG固体激光器

报道了一种基于光谱合束的Nd:YAG固体激光器双波长光源。系统由两个固体Nd:YAG脉冲激光器通过光谱合束组合而成,两个固体Nd:YAG脉冲激光器可独立工作,有利于输出脉冲的波长调谐、功率调节和相对延迟调整。通过光栅的色散特性以及输出镜的共同外腔反馈将各个激光器锁定在不同波长,从而实现合束,获得的激光源中心波长锁定在1 061.5 nm和1 064.6 nm,两谱线中心间距为3.1 nm,组合光束的输出能量为173 mJ,组合光束的光束质量因子M2为2.8×2.2;两个Nd:YAG激光器独立工作的输出能量分别为94 mJ和92 mJ,在合束方向上的光束质量因子M2分别为2.7和2.1,在非合束方向上的光束质量因子M2分别为2.2和1.9;组合光束的输出能量为两个Nd:YAG激光器能量总和的93%,组合光束的光束质量因子与单个Nd:YAG激光束的光束质量因子M2基本相同。该双波长激光源满足波长间隔小、输出功率大小相近、同光轴等要求,在太赫兹波产生、测速激光雷达以及医疗仪器等应用领域具有重要作用。

新能源极端出力特性及典型电力电量平衡场景研究

随着新能源发电占比的增加,电力系统的电力电量平衡呈现不确定性强、电力过剩/短缺交替出现等特征,给电力系统的供电可靠性带来了严重的影响。基于新能源出力实际运行特性和未来电源发展趋势,研究了含水电的新型电力系统的典型电源结构场景,并以此为基础,建立了电力电量平衡量化分析模型。通过算例结果量化了未来新能源发展场景下的典型电力电量平衡场景及系统灵活调节能力的需求,分析了新能源极端低/高出力对电力平衡的影响。研究可为我国新型电力系统构建提供决策参考。

基于磁性液体的磁浮式振动俘能器系统建模与输出性能分析

针对现有振动俘能器输出功率低、工作频带范围小等问题,提出了一种基于磁性液体的非线性磁浮式振动俘能器新型结构。提出新型俘能器的结构形式,分析其工作原理,建立磁偶极子非线性力学模型,对比仿真结果与试验数据,验证其准确性;分析磁性液体的二阶浮力和黏性阻尼,建立其数学模型,运用多尺度变换方法求解俘能器动力学方程的近似解,进而获得输出性能响应模型;分析三类系统结构参数和激励加速度变化对俘能器输出性能的影响,对比了有无磁性液体时俘能器的输出性能。结果表明:磁铁间距、悬浮磁铁与磁性液体的总质量和激励加速度能有效地改变俘能器的工作频率范围和输出功率幅值,而阻尼比主要影响输出功率幅值。新型俘能器输出电压峰峰值和输出功率峰值分别达到426.88 mV和0.56 mW,增加磁性液体后输出电压和功率分别提升了22.67%和75%,对比其它低频振动俘能器,具有较优的输出功率特性。新型磁浮式俘能器的结构形式与建立的动力学模型能为拓宽此类俘能器工作频带范围和增强输出功率性能提供新的解决思路,具有良好的参考价值。