Review on combined wind power generation and energy storage systems

储能系统由于能够实现电能的时空平移,具有响应速度快,规模化等优点,是改善风电波动性,提高其并网能力的有效手段,构建风储联合发电系统成为目前研究重点.简单介绍了风电并网对电力系统的影响及不同类型电池储能技术的发展现状,给出了部分国内外风储联合发电系统的示范工程,并分析了平滑风电功率波动,跟踪计划出力曲线和削峰填谷3种主要运行方式,重点阐述了目前风储联合发电系统控制策略和储能容量配置研究现状,对进一步开展风储联合发电系统的研究进行了展望,指出经济性仍然是制约储能技术应用的关键问题之一,提高包含储能单元的风储联合发电系统的经济性是今后的研究重点.     

Effects of power reserve control on wind turbine structural loading

As the penetration of wind energy in worldwide electrical utility grids increases, there is a growing interest in the provision of active power control (APC) services from wind turbines and power plants to aid in maintaining grid stability. Recent research has focused on the design of active power controllers for wind turbines that can provide a range of APC services including inertial, primary frequency and secondary frequency control. An important consideration for implementing these controllers in practice is assessing their impact on the lifetime of wind turbine components. In this paper, the impact on the structural loads of a wind turbine providing a power reserve is explored by performing a load suite analysis for several torque‐based control strategies. Power reserve is required for providing those APC services that require the ability of the wind turbine to supply an increase in power. To study this, we performed a load suite on a simulated model of a research turbine located at the National Wind Technology Center at the National Renewable Energy Laboratory. Analysis of the results explores the effect of the different reserve strategies on turbine loading. In addition, field‐test data from the turbine itself are presented to augment and support the findings from the simulation study results. Results indicate that all power‐reserve strategies tend to decrease extreme loads and increase pitch actuation. Fatigue loads tend to be reduced in faster winds and increased in slower winds, but are dependent on reserve‐controller design. Copyright © 2015 John Wiley & Sons, Ltd.     

Inhibition of wind power fluctuations of battery energy storage system adaptive control strategy design

为了增加电池储能系统针对大规模风电并网对电网系统的友好性,降低风电功率波动对电网的不利影响,本文提出以电池荷电状态和风电功率为反馈量,改变平抑时间常数和电池储能系统充放电目标功率为目标的平抑风电功率波动的自适应控制策略。经仿真验证,上述策略能有效避免电池的荷电状态大幅波动,延长电池使用寿命,从而减小电池储能系统的安装容量,最大限度地发挥电池储能系统的作用。     

基于混合深度学习的风电功率预测及一次调频应用

为了解决高比例不确定性风电接入电力系统带来强烈调频需求的问题,提出了基于混合深度学习模型的风电功率预测及其一次调频应用方法。首先,采用孤立森林(Isolated Forest, IF)对历史数据进行异常值处理,提高数据质量,其次,构建卷积神经网络(Convolutional Neural Network, CNN)、双向长短期记忆(Bidirectional Long Short Term Memory, BiLSTM)和注意力机制(Attention Mechanism, AM)的混合深度学习模型对风电功率进行预测。最后,依据功率预测精度配置超级电容器储能,设计储能调频控制原则,弥补风电机组自身预测误差,并协同风电机组参与电力系统一次调频。基于预测结果为4台风电发电机组2个负荷区域仿真系统配置超级电容器储能系统,利用digsilent平台进行了风预测误差和负荷波动下的一次调频仿真。结果表明：所提IF-CNN-BiLSTM-AM模型比BP和LSTM基准模型预测误差(MSE)降低了81.53%和51.44%,具有最优的预测性能;设计的风储一次调频模型与原则可有效应对风电预测误差和负荷波动...     

Empowering the electric grid: Can SMES coupled to wind turbines improve grid stability?

The transition to a low carbon energy portfolio necessitates a reduction in the demand of fossil-fuel and an increase in renewable energy generation and penetration. Wind energy in particular is ubiquitous, yet the stochastic nature of wind energy hinders its wide-spread adoption into the electric grid. Numerous techniques (improved wind forecasting, improved wind turbine design and improved power electronics) have been proposed to increase the penetration of wind energy, yet only a few have addressed the challenges of wind intermittency, grid stability and flexibility simultaneously. The problem of excess wind energy results in wind curtailment and has plagued large scale wind integration. NREL's HOMER software is used to show that a strong negative correlation exists between the cycles to failure of a storage device and the excess wind energy on the system. A 1 MJ magnesium-diboride superconducting magnetic energy storage (SMES) system is designed to alleviate momentary interruptions (lasting from a few milli-seconds to a few minutes) in wind turbines. The simulation results establish the efficacy of SMES coupled with wind turbines improve output power quality and show that a 1 MJ SMES alleviated momentary interruptions for ∼50 s in 3 MW wind turbines. These studies suggest that SMES when coupled to wind turbines could be ideal storage devices that improve wind power quality and electric grid stability.     

The energy storage system output control strategy to improve theshort term windpower forecastingaccuracy rate

目前对于储能系统应用于平抑新能源发电的波动性、移峰填谷等场景的控制策略已有文献研究,但对于风功率预测准确率影响风电场效益的机制下储能系统应用的可行性尚未见研究。本文提出了一种以减小风电场短期功率预测偏差为目标的储能系统出力控制策略,控制策略以风电场实时出力数据（秒级）为数据源,采用线性外推加以移动平均优化的方法预测下一时刻风电场出力,通过比较风电场短期功率预测值与实时预测值,计算储能系统期望出力,并根据储能系统不同SOC区间内的出力能力进行约束,输出储能系统出力指令,最后进行了仿真验证。结果表明,本文提出的储能系统出力控制策略,能够使风电场通过配置储能系统,减少短期功率预测准确度考核,对风电场的精益化运行具有指导意义。     

大规模风电对电力系统的影响和应对策略

综述了大规模风电接入电网对电力系统带来的影响。阐述了当前风力发电的特点和与风电相关的无功电压问题、暂态稳定性问题、频率问题、电能质量问题。针对不同问题总结了可行的解决方法和研究热点。论述了风力发电2个重要的研究方向：风电场综合控制技术和风电功率预测技术。     

Impact of wind power generating system integration on frequency stabilization in multi-area power system with fuzzy logic controller in deregulated environment

Among the available options for renewable energy integration in existing power system, wind power is being considered as one of the suited options for future electrical power generation. The major constraint of wind power generating system (WPGS) is that it does not provide inertial support because of power electronic converters between the grid and the WPGS to facilitate frequency stabilization. The proposed control strategy suggests a substantial contribution to system inertia in terms of short-term active power support in a two area restructured power system. The control scheme uses fuzzy logic based design and takes frequency deviation as input to provide quick active power support, which balances the drop in frequency and tie-line power during transient conditions. This paper presents a comprehensive study of the wind power impact with increasing wind power penetration on frequency stabilization in restructured power system scenario. Variation of load conditions are also analyzed in simulation studies for the same power system model with the proposed control scheme. Simulation results advocates the justification of control scheme over other schemes.     

A smooth co-ordination control for a hybrid autonomous power system (HAPS) with battery energy storage (BES)

The standalone hybrid power system constitutes a synchronous generator driven by a diesel engine, renewable energy source (wind) apart from a battery energy storage system. A coherent control strategy to regulate the voltage and frequency of the standalone grid is proposed in this paper. The system is simulated using Matlab/Simulink for preliminary validation and further tested on a laboratory prototype which involves a TMS320LF2407A DSP controller to digitally implement the control strategy. The dynamic behavior of the system is perused through the direct connection of an induction machine. The control strategy is verified for step changes in load and variation in wind power.     

飞轮储能技术研究五十年评述CSCD

本文回顾了飞轮储能技术研发50年的历程,分析了飞轮储能技术特点、应用领域以及关键技术问题。飞轮储能具有功率密度高、循环寿命长、响应迅速、能量可观性好以及环境友好的优点。当前,研制的飞轮储能系统单体能量为0.5~130 kW·h,功率为0.3~3000 kW。重点关注了飞轮用低成本高比强度新材料、高温超导磁悬浮技术。飞轮储能在电能质量调控、不间断过渡电源以及电网调频领域实现了商业化应用,在车辆混合动力领域的示范应用中实现节能20%~30%,处于产业应用的临界点。针对电网规模大功率、高能量储能需求,发展趋势是由数十千瓦时以下发展到百千瓦时,并通过阵列化组装成10~100 MW储能系统,放电时间可拓展到1 h。     

Stabilization and control of tie-line power flow of microgrid including wind generation by distributed energy storage

High penetration of wind generation in electrical microgrids causes fluctuations of tie-line power flow and significantly affects the power system operation. This can lead to severe problems, such as system frequency oscillations, and/or violations of power lines capability. With proper control, a distribution static synchronous compensator (DSTATCOM) integrated with superconducting magnetic energy storage (SMES) is able to significantly enhance the dynamic security of the power system. This paper proposes the use of a SMES system in combination with a DSTATCOM as effective distributed energy storage (DES) for stabilization and control of the tie-line power flow of microgrids incorporating wind generation. A new detailed model of the integrated DSTATCOM-SMES device is derived and a novel three-level control scheme is designed. The dynamic performance of the proposed control schemes is fully validated using MATLAB/Simulink.     

A novel sensorless current shaping control approach for SVPWM inverter with voltage disturbance rejection in a dc grid–based wind power generation system

A novel sensorless current shaping (CS) control strategy is proposed to avail better power quality (PQ) of a dc grid–based wind power generation system (WPGS) used on a poultry farm by generating an appropriate reference current for space vector pulse width modulation (SVPWM) inverter. The proposed CS strategy also offers adequate control for parallel operation of multiple generators and inverter applications, without requiring voltage and frequency synchronization. Further, to control the poultry farm–based WPGS, a two‐stage control loop is implemented such as energy flow control loop (EFCL) and harmonic control loop (HCL). The first loop is used to regulate the power flow, and the second loop is used to compensate harmonics. A mathematical current decomposition technique is suggested for an appropriate resistance emulation to realize a better power flow, higher harmonic rejection, and better inverter operation. In this planned approach for attaining constant wind speed, an electric ventilation fan in the poultry farm is used. A combined hybrid dc and ac grid approaches are suggested for facilitating variable load integration in a poultry farm–based microgrid system. Moreover, for achieving better power management during the islanded mode of operation, the battery energy storage (BES) device is integrated with the dc grid through a bidirectional converter. The proposed WPGS design and control approach has been simulated through MATLAB/Simulink software under various test conditions, to demonstrate the operational capability, to achieve better PQ, and to increase the flexibility and reliability in the microgrid operation.     

独立式风光互补发电系统中最大功率控制策略研究

独立风光互补发电系统从能量的角度来看可以分为3部分,即能量获取部分,能量存储部分以及能量消耗部分。主要介绍了能量获取所涉及的风力机最大功率运行和光伏电池最大功率跟踪这2个问题的控制策略,同时对能量存储部分所涉及的蓄电池充放电的控制策略进行了介绍,其中对充电策略的三阶段法做了比较详细的分析。最后对最大功率控制策略的研究方法作了系统的评述并对该领域今后的研究方向作了展望。     

无刷双馈风力发电机组的自抗扰功率解耦控制

对无刷双馈风力发电机组稳态运行时的功率分配关系进行了详细分析,在此基础上确定了最大风能捕获的控制策略.将自抗扰控制应用到无刷双馈电机有功功率与无功功率的解耦控制,将功率控制系统分解为有功功率子系统和无功功率子系统,从而建立了风力发电机组完整的功率控制模型.基于Matlab/Simulink的仿真结果表明无刷双馈风力发电机组自抗扰控制成功实现了有功功率与无功功率的解耦控制,不仅能够实现最大风能捕获,而且可以根据电网的实际需求调节机组无功功率的输出,验证了控制算法的有效性.     

基于最优滚动控制域的储能控制策略

针对风电场预测功率与实际功率不匹配以及风力发电不确定性问题,提出一种以补偿风电预测误差和平抑风电波动为目标的储能控制策略。该策略以先进控制理论为基础,结合储能补偿预测区间和储能平抑风电波动区间,提取考虑储能运行成本的储能最优滚动控制域。首先,针对储能补偿预测误差目标,制定储能控制策略,提取允许误差内的储能补偿区间;其次,考虑风电功率波动要求及荷电状态（SOC）约束,采用模型预测控制求解出储能滚动控制序列,确定储能平抑区间。最后,考虑储能运行成本,将补偿区间和平抑区间相结合,制定储能最优滚动控制区间,以此为基础确定储能容量。以中国新疆某风电场为例,对该文提出的储能控制策略与传统控制策略进行对比验证,验证所提策略的可行性和有效性。     

含风电的多域互联电力系统负荷频率控制方法

为确保风机参与调整系统负荷频率,建立了三区域含风力发电的互联电力系统负荷频率控制模型;同时,为抑制整个系统内部参数的变化、风能波动及负荷扰动所造成的负荷频率波动,又设计出一个分散的滑模控制器并用于仿真分析,当整个系统在进入滑动模态后,对外界的参数变化具有时不变性。仿真结果表明,所设计的滑模控制器比传统的控制器响应更快、超调量小,有效抑制了负荷频率波动,且当考虑发电机变化率约束条件时,所设计的滑模控制器仍能有效控制系统稳定。     

考虑预测误差分析的混合储能补偿优化策略

为提高风电场预测功率精度,对于风电场和混合储能构成的风储混合系统,提出基于预测信息搭建的混合储能补偿方案。首先,依据风电预测误差进行概率统计分析,提出风电功率预测误差的分层补偿策略,制定针对补偿预测误差的允许误差域及置信区间补偿域。其次,利用储能对不同误差层的预测误差给出相应的储能补偿方案,基于小波包分解将超出区域外待补偿预测误差分解,通过不平衡功率DFT分频法确定临界点作为功率型储能和能量型储能的目标分配值,对于荷电状态越限问题通过自适应模糊控制进行二次修正。最后,以新疆某风电场为例进行仿真分析,结果表明所提策略可有效减少风电功率预测误差。     

Performance of PI controller for control of active and reactive power in DFIG operating in a grid-connected variable speed wind energy conversion system

Due to several factors, wind energy becomes an essential type of electricity generation. The share of this type of energy in the network is becoming increasingly important. The objective of this work is to present the modeling and control strategy of a grid connected wind power generation scheme using a doubly fed induction generator (DFIG) driven by the rotor. This paper is to present the complete modeling and simulation of a wind turbine driven DFIG in the second mode of operating (the wind turbine pitch control is deactivated). It will introduce the vector control, which makes it possible to control independently the active and reactive power exchanged between the stator of the generator and the grid, based on vector control concept (with stator flux or voltage orientation) with classical PI controllers. Various simulation tests are conducted to observe the system behavior and evaluate the performance of the control for some optimization criteria (energy efficiency and the robustness of the control). It is also interesting to play on the quality of electric power by controlling the reactive power exchanged with the grid, which will facilitate making a local correction of power factor.     

考虑调频可靠性的风储系统多目标优化策略

针对风电强不确定性导致的电力系统频率不稳定问题,提出了考虑调频可靠性的风储系统多目标优化策略,以风电功率预测数据为基础,利用风储系统对电力系统提供频率支撑,保证电力系统频率稳定。该策略包含补偿和调频两个步骤,首先提出基于储能系统的风电预测误差补偿策略,并将风电预测误差补偿至10%以内,同时为风电场预留20%的调频容量。其次,考虑系统调频经济性,提出基于模型预测控制的风储系统参与电力系统频率控制策略,采用风电备用和储能系统进行调频。最后,将上述策略作为约束条件,采用多目标哈里斯鹰算法求解满足上述双目标的储能容量用以验证策略的有效性。仿真结果表明：本文所提调频策略能够在保障调频可靠性的基础上,降低电网频率波动,满足风电系统和电网的高效、安全运行。     

电网故障条件下风储联合系统无功自适应控制

针对电网三相对称故障条件下风电场电压不稳定的问题,文章提出了一种基于神经元的风储联合系统无功功率自适应控制策略,该策略以风储联合系统公共耦合点(Point of Common Coupling,PCC)的电压和电流为控制器的输入,采用Hebb学习算法作为自适应律,以获得准确的无功补偿。通过动态调整控制器的参数,使储能系统协调风电达到自适应输出无功功率的效果,提高系统在电网故障下的电压稳定性和风电故障穿越能力。最后,利用Matlab/Simulink仿真验证了该控制策略的有效性和正确性,与常规PI控制策略相比,文章所提出的控制策略可使风储系统迅速提供无功功率,PCC点的电压得到明显上升。