基于复合储能系统平抑风电场波动功率研究

由于风能的不稳定性,风电场输出功率带有波动性和间歇性,某种程度上导致风力发电并网难以及“弃风限电”等问题。依据风电输出功率波动特性,提出由先进压缩空气储能和钒液流电池组成的复合储能系统,用于平抑风电场输出功率波动。并通过模拟仿真验证了钒液流电池对风电场侧快速波动功率的补偿和平抑具有良好效果。结果表明,先进压缩空气储能系统具备大功率大容量特性的同时,适合应用在风电场并网侧调节风电场输出功率     

平抑风电功率波动的飞轮储能系统容量配置方法北大核心CSCD

为使风电场有功功率变化满足国家标准中有功功率变化限制的推荐值范围,采用飞轮储能系统平抑风电场有功功率输出。基于低通滤波方法,由飞轮储能系统响应风电场有功功率输出的高频成分,降低并网功率波动对电网一次调频的影响。通过建立不同截止频率和不同飞轮储能系统功率容量下的双层寻优模型,得到满足飞轮储能系统约束条件、风电并网有功功率变化要求和经济性指标的最优化飞轮储能系统容量。建立飞轮储能系统模型,仿真验证飞轮储能系统能够较好地响应功率指令,有效平抑风电功率波动。     

平抑风电功率波动的储能容量经济配置方法

以东北某风电场月出力实测数据为对象,通过分析该风电场的功率波动特性,提出了储能系统功率、容量配置方法。该方法以储能系统投资收益最大为目标,结合储能平滑风电出力效果,获取经济性最优的储能系统容量配置方案。结果表明,该优化配置方案在平滑风电功率的前提下,具有良好的经济效益,为风电场中配置储能系统、推进储能系统规模化应用提供了参考。     

混合储能辅助风电场平滑出力的功率配比方法研究

随着风电渗透率的增大,风电并网时对电网产生的波动也逐渐增大,采用储能系统对风电场出力进行平滑处理,可以使风电满足规定的并网要求.针对风电场出力波动成分的频率范围较宽的问题,采用混合储能系统(飞轮+电化学储能)进行不同波动频率成分平滑,提出一种运行数据驱动的混合储能容量配置方法,利用抗脉冲平均滤波法对风电场出力数据序列进...     

计及调频备用的储能平抑风电功率波动控制策略北大核心CSCD

新能源场站配置储能系统可以平抑输出功率的波动、承担新能源机组调频义务。若储能仅考虑单一平抑波动工况时可能会造成风储联合系统调频有功备用不足。因此本文提出一种考虑调频有功备用与荷电状态恢复的平抑风电功率波动策略,首先利用聚类算法提取储能平抑波动典型工况,计算储能平抑波动功率需求和剩余有功功率;其次,结合国标对风电场有功备用相关标准,利用储能调频备用与风电减载联合提供有功备用,并对储能平抑波动功率设置限幅;最后,利用模糊控制理论设计储能系统边缘区荷电状态恢复策略。基于实际风电场运行数据进行仿真分析,结果表明所提出的方法可在储能系统平抑风电波动时提供有功备用以及边缘区荷电状态恢复。     

基于超级电容储能的风电并网功率调节控制系统

风能是一种随机变化的能源,风速变化会导致风电机组输出功率的波动,对电网的电能质量产生影响,使用储能装置可以改善风电质量。通过在风电场并网的交流侧母线上并联超级电容储能单元,能实现对风电场功率的调节,减小功率的波动。文章设计了风电场并网及储能系统各部分的控制策略,在Matlab/Simulink仿真环境下创建了系统的仿真模型,验证了控制策略的正确性。仿真系统最终实现了电机侧变流器最大风能跟踪、电网侧变流器单位功率因数并网和超级电容储能单元对风电场并网功率的调节。     

风电场配套电化学储能系统的设计研究

风电场配套建设储能系统可有效平滑风电输出的有功功率的波动,使风电满足接入电网相关标准的要求,减少"弃风"现象,增加风电场业主的收益,使风电场实现暂态有功功率紧急响应和暂态电压紧急支撑的功能,从而参与电网的调峰、调频.基于风电场配套储能系统的理论研究和实际工程案例,提出了一套风电场配套电化学储能系统的电气设计方案,以期为...     

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。     

构网型储能系统与风力发电的协同控制研究

在风电场直流侧配备储能以实现虚拟同步机控制的方案需要对风电场的硬件进行改造升级,成本较高;在风电场交流侧配备储能虽成本较低,但现有的风电场与交流侧储能独立控制的方法对风电场出力波动的平抑作用有限。在不改变风电场现行控制基础上,文章提出一种风电场及其交流侧配备的构网型储能设备的虚拟同步发电机协同控制方案,可使新能源和储能联合系统呈现电压源效应并提供系统阻尼和惯量,考虑了储能容量对控制效果的限制作用,并提出了储能容量与风电场装机量的最佳配比,通过仿真实验对该方案的有效性进行了论证。结果表明：通过协同控制风电场与其交流侧配备的构网型储能出力,可以与风电场直流侧配备储能的虚拟控制实现相同的频率与电压支持效果,并有效平抑风力发电的波动性。     

含电池储能风电场的发电系统风险评估

考虑风电机组的功率特性和故障率等因素建立单个风机的停运模型,结合风速的自回归滑动平均模型和风电场尾流效应的影响建立风电场的可靠性模型;考虑电池储能的充放电约束、容量约束和故障率建立电池储能系统的可靠性模型,在此基础上,结合风电场不同调度策略建立含电池储能风电场的可靠性模型。考虑常规机组的随机故障和负荷的随机波动,基于序贯蒙特卡洛方法建立含电池储能风电场的发电系统风险评估模型,并给出评估指标。在Matlab中编写相关评估程序,通过对IEEE-RTS 79算例进行仿真,从风险管控方面给出能降低系统风险的电池储能充放电约束、电池储能电量和风电场调度策略,为风电场用电池储能系统的设计和风能调度策略的选取提供重要参考。     

Application of energy capacitor system to wind power generation

In this paper, it is reported that energy capacitor system (ECS), which combines power electronic devices and electric double‐layer capacitor, can significantly decrease voltage and power fluctuations of grid‐connected fixed‐speed wind generator. The proper selection of wind farm output power reference is still a problem for smoothing the wind farm output power. This paper proposes exponential moving average to generate the reference output power of a grid‐connected wind farm. The objective of the control system is to follow the line power reference by absorbing or providing real power to or from the ECS. Moreover, the necessary reactive power can also be supplied to keep the wind farm terminal voltage at the desired reference level. Real wind speed data were used in the simulation analyses, which validate the effectiveness of the proposed control strategy. Simulation results clearly show that our proposed ECS can be suitable for wind power application. Copyright © 2007 John Wiley & Sons, Ltd.     

采用混合储能的风电场输出平滑控制

以装备DFIG机组的风电场为例,研究分析了混合储能系统的配置方案。针对风电功率的波动,提出了一种基于频率分解的混合储能平滑控制方法。设计了相应的储能装置控制器,使得一定时间内风电机组或风电场接近恒定的功率,从而体现出常规电源的可控性。针对不同的储能配置方案进行了仿真实验,结果表明采用该方法可以使整个风电场按照调度的指令,在一定的时间范围内,保持输出功率在电力系统调度范围之内。     

计及集电线路和内部损耗的风电场模型分析比较

风电的接入会改变电网原有的潮流分布而对电网电压稳定性产生影响。潮流计算作为风电接入系统研究的基础,为得到其计算结果的准确性而建立风电场稳态模型具有重要的意义。以往的风电场系统潮流计算都是把整个风电场等效为一个风机处理,并没有详细讨论风电场内部的电网结构,潮流计算无法深入到风电场内部。在DigSILENT/PowerFactory中建立了改进的潮流计算模型,充分考虑了由双馈异步发电机组成的大型风电场的集电系统以及风电机组间电缆的功率损耗对稳态潮流计算的影响。     

Identification of vulnerable lines in power grids with wind power integration based on a weighted entropy analysis method

Vulnerable overhead electricity lines are a cause of serious risk to power distribution grids as damage can be the cause of large scale blackouts and cascading failures. With the integration of large scale wind power into generating capacity, both the topology structure and the distribution characteristics of power flow in distribution grid have undergone various changes that have increased line vulnerability. A novel approach to identify vulnerable lines based on the weighted entropy analysis method is proposed in this paper. In this approach, an assessment index, named the incremental power flow entropy, is first developed, which is used to describe influences caused by variation of the lines' capability of carrying power flow transfers on the vulnerability of the lines themselves at the same aggregation level. A second assessment index, named structural importance, describes the structural changes of a power grid that are caused by the integration of wind-generated electric power. The two assessment indices then are merged into one index by using the entropy weight analysis method, which can assess the vulnerability of the lines from the two aspects of power flow transmission and structural links. Vulnerability analysis under different situations, such as with and without the integration of the wind farm, and sharp fluctuations in wind speed at the wind farm, were carried out on an IEEE 39-bus system integrated with a 75 MW wind farm. Simulation results verified that the proposed assessment index not only can identify the vulnerable lines in a power grid with wind farm integration but also accurately reflected the vulnerability of the internal lines of the wind farm itself.     

改善风电并网电能质量的飞轮储能系统能量管理系统设计

设计了应用于改善电网电能质量场景下飞轮储能系统的双层结构能量管理系统,其中能量管理系统的上层——决策管理层利用模糊算法,考虑飞轮储能系统状态和平抑风电功率波动需求来确定飞轮储能装置的充放电功率参考值,下层——调度控制层通过双环控制背靠背双PWM变流器实现飞轮储能与电网间的功率交换。在Matlab/Simulink下仿真分析飞轮储能的运行状态和比较风电场采用飞轮储能调节有功功率前后的公共连接点(point of common coupling,PCC)处电压波动,仿真结果验证了飞轮储能系统能量管理系统的有效性,可提高储能装置的利用效率,改善电能质量。     

基于功率谱密度的风电功率特性分析

风电有功功率波动特性的分析,对指导发电和电网运行非常重要.根据内蒙古赤峰东山风电场运行的实测数据,运用功率谱密度分析的方法,对风电有功功率的波动特性进行了分析.结果表明,风电功率的功率谱密度在超过4个数量级频域范围内符合Kolmogorov谱分布理论,且装机容量的增加,对风电功率的汇聚效应具有明显的影响.     

Spatial and temporal analysis of electric wind generation intermittency and dynamics

A spatial and temporal analysis of wind power generation characteristics was conducted in order to determine the implications of intermittent wind generation dynamics on the profile of the electric loads that must be balanced by dispatchable electrical generators on the electric grid. A parametric analysis was conducted to evaluate the sensitivity of the typical magnitudes of wind power fluctuations on different timescales, power variation range, typical daily and seasonal wind profiles to wind farm size and regional distribution. A methodology to evaluate wind dynamics based on power spectral density analyses have been developed. Results indicate that increasing the size of a local wind farm significantly reduced the magnitude of wind power fluctuations on timescales faster than 12 h, with the largest reductions occurring at the fastest timescales. Additional reductions in power fluctuations can be achieved with the implementation of local and regional distribution of wind turbines in disperse high wind areas. In these cases, it was discovered that the timescale band within which the largest reductions in power fluctuations occurred was dependent on regional geographic features, and did not necessarily correspond to the fastest timescales. In addition, it was also discovered that the aggregation of wind power from different regions could produce a more uniform frequency distribution of power fluctuation reductions.     

Impact of wind power in autonomous power systems—power fluctuations—modelling and control issues

This paper describes a detailed modelling approach to study the impact of wind power fluctuations on the frequency control in a non‐interconnected system with large‐scale wind power. The approach includes models for wind speed fluctuations, wind farm technologies, conventional generation technologies, power system protection and load. Analytical models for wind farms with three different wind turbine technologies, namely Doubly Fed Induction Generator, Permanent Magnet Synchronous Generator and Active Stall Induction Generator‐based wind turbines, are included. Likewise, analytical models for diesel and steam generation plants are applied. The power grid, including speed governors, automatic voltage regulators, protection system and loads is modelled in the same platform. Results for different load and wind profile cases are being presented for the case study of the island Rhodes, in Greece. The scenarios studied correspond to reference year of study 2012. The effect of wind fluctuations in the system frequency is studied for the different load cases, and comments on the penetration limits are being made based on the results. Copyright © 2010 John Wiley & Sons, Ltd.     

Framework design of a hybrid energy system by combining wind farm with small gas turbine power plants

Owing to the stochastic characteristic of natural wind speed, the output fluctuation of wind farm has a negative impact on power grid when a large-scale wind farm is connected to a power grid. It is very difficult to overcome this impact only by wind farm itself. A novel power system called wind-gas turbine hybrid energy system was discussed, and the framework design of this hybrid energy system was presented in detail in this paper. The hybrid energy system combines wind farm with several small gas turbine power plants to form an integrated power station to provide a relatively firm output power. The small gas turbine power plant has such special advantages as fast start-up, shutdown, and quick load regulation to fit the requirement of the hybrid energy system. Therefore, the hybrid energy system uses the output from the small gas turbine power plants to compensate for the output fluctuation from the wind farm for the firm output from the whole power system. To put this hybrid energy system into practice, the framework must be designed first. The capacity of the wind farm is chosen according to the capacity and units of small gas turbine power plants, load requirement from power grid, and local wind energy resource distribution. Finally, a framework design case of hybrid energy system was suggested according to typical wind energy resource in Xinjiang Autonomous Region in China.     

Framework design of a hybrid energy system by combining wind farm with small gas turbine power plants

Owing to the stochastic characteristic of natural wind speed, the output fluctuation of wind farm has a negative impact on power grid when a large-scale wind farm is connected to a power grid. It is very difficult to overcome this impact only by wind farm itself. A novel power system called wind-gas turbine hybrid energy system was discussed, and the framework design of this hybrid energy system was presented in detail in this paper. The hybrid energy system combines wind farm with several small gas turbine power plants to form an integrated power station to provide a relatively firm output power. The small gas turbine power plant has such special advantages as fast start-up, shutdown, and quick load regulation to fit the requirement of the hybrid energy system. Therefore, the hybrid energy system uses the output from the small gas turbine power plants to compensate for the output fluctuation from the wind farm for the firm output from the whole power system. To put this hybrid energy system into practice, the framework must be designed first. The capacity of the wind farm is chosen according to the capacity and units of small gas turbine power plants, load requirement from power grid, and local wind energy resource distribution. Finally, a framework design case of hybrid energy system was suggested according to typical wind energy resource in Xinjiang Autonomous Region in China.