Besides common characteristics of wind power,there are some special characteristics in China power system,including large-scale,long distance transmission and lack of flexible regulating power sources.These special ch...Besides common characteristics of wind power,there are some special characteristics in China power system,including large-scale,long distance transmission and lack of flexible regulating power sources.These special characteristics make power dispatch more challenging in China.Many studies have been carried out and some improvements are presented including wind power monitoring and control as well as evaluation of wind power integration capabilities.As a demonstration project,the technologies are integrated into the energy management system and are implemented in the Northwest China power system.They provide effective measures for wind power dispatch in the grid.展开更多
A novel fault ride-through strategy for wind turbines,based on permanent magnet synchronous generator,has been proposed.The proposed strategy analytically formulates the reference current signals,disregarding grid fau...A novel fault ride-through strategy for wind turbines,based on permanent magnet synchronous generator,has been proposed.The proposed strategy analytically formulates the reference current signals,disregarding grid fault type and utilizes the whole system capacity to inject the reactive current required by grid codes and deliver maximum possible active power to support grid frequency and avoid generation loss.All this has been reached by taking the grid-side converter’s phase current limit into account.The strategy is compatible with different countries’grid codes and prevents pulsating active power injection,in an unbalanced grid condition.Model predictive current controller is applied to handling rapid transients.During faults,the energy storage system maintains DC-link voltage,which causes voltage fluctuations to be eliminated,significantly.A fault ride-through strategy was proposed for PMSG-based wind turbines,neglecting fault characteristics,second,reaching maximum possible grid support in faulty grid conditions,while avoiding over-current and third,considerable reduction in energy storage system size and power rating.Inspiring simulations have been carried out through MATLAB/SIMULINK to validate the feasibility and competency of the proposed fault ride-through method and efficiency of the entire control system.展开更多
风电大规模并网导致系统惯量严重降低,恶化了系统的频率稳定性。针对上述问题,该文结合非线性预测理论以及扩张状态观测理论(extended state observer,ESO)提出双馈风机参与电网频率调节的短期频率支撑方法。首先,建立与系统频率偏差和...风电大规模并网导致系统惯量严重降低,恶化了系统的频率稳定性。针对上述问题,该文结合非线性预测理论以及扩张状态观测理论(extended state observer,ESO)提出双馈风机参与电网频率调节的短期频率支撑方法。首先,建立与系统频率偏差和风机转速相关的目标状态方程,并计算不同控制目标量对应的预测阶;其次,根据非线性预测理论计算预测矩阵,对未来时刻状态跟踪误差进行预测,并求得非线性控制律;最后,引入扩张状态观测器对非线性控制律中的复杂李导数运算进行观测,减轻控制律所需的计算负担。通过MATLAB/SIMULINK搭建含风电系统进行仿真验证,结果表明,所提方法有效地改善了电网的频率响应,并且无需单独设计转速恢复环节,能够实现风机转速的自恢复。展开更多
针对直驱式永磁同步风力发电系统风速多变、非线性和强扰动的问题,提出一种基于模糊控制和线性自抗干扰控制(Linear Active Disturbance Retection Control,LADRC)的混合控制方法。首先对线性自抗扰中的扩张状态观测器(Linear Extended ...针对直驱式永磁同步风力发电系统风速多变、非线性和强扰动的问题,提出一种基于模糊控制和线性自抗干扰控制(Linear Active Disturbance Retection Control,LADRC)的混合控制方法。首先对线性自抗扰中的扩张状态观测器(Linear Extended State Observer,LESO)进行改进,提高对扰动观测的能力,同时利用模糊控制动态调整LADRC控制参数,增强系统的抗干扰能力和鲁棒性。仿真结果表明,与传统PI控制器相比,该方法能够更好地估计风速引起的转矩波动,准确跟踪额定转速,实现风能利用最大化。展开更多
陆上风电全直流系统能有效解决谐波谐振、无功传输等问题,是未来风力发电系统的发展方向,其低电压穿越(low voltage ride through,LVRT)能力是系统稳定运行的保障。文中基于系统拓扑及其运行控制策略,剖析网侧电压跌落时聚集在陆上风电...陆上风电全直流系统能有效解决谐波谐振、无功传输等问题,是未来风力发电系统的发展方向,其低电压穿越(low voltage ride through,LVRT)能力是系统稳定运行的保障。文中基于系统拓扑及其运行控制策略,剖析网侧电压跌落时聚集在陆上风电全直流发电系统直流环节的盈余功率,分析常规LVRT策略在风电全直流系统中的适用性。考虑电网对风电系统储能配置的要求,兼顾风电机组自启动特性提出利用电池储能存储低电压故障下直流母线的盈余功率实现LVRT的控制策略。在PSCAD/EMTDC仿真平台搭建陆上风电全直流发电系统模型,对所提策略进行仿真验证。结果表明,所提控制策略能够提升风电全直流发电系统的LVRT能力,促进直流母线电压的快速恢复;电池储能在故障期间吸收盈余能量,在风电机组自启动期间提供能量,提高了能量与储能的利用率。展开更多
基金supported by National Natural Science Foundation of China(No.51177019,61074100,60974036)Doctoral Fund of Ministry of Education of China(No.20090092110020)and the State Grid Corporation of China
文摘Besides common characteristics of wind power,there are some special characteristics in China power system,including large-scale,long distance transmission and lack of flexible regulating power sources.These special characteristics make power dispatch more challenging in China.Many studies have been carried out and some improvements are presented including wind power monitoring and control as well as evaluation of wind power integration capabilities.As a demonstration project,the technologies are integrated into the energy management system and are implemented in the Northwest China power system.They provide effective measures for wind power dispatch in the grid.
文摘A novel fault ride-through strategy for wind turbines,based on permanent magnet synchronous generator,has been proposed.The proposed strategy analytically formulates the reference current signals,disregarding grid fault type and utilizes the whole system capacity to inject the reactive current required by grid codes and deliver maximum possible active power to support grid frequency and avoid generation loss.All this has been reached by taking the grid-side converter’s phase current limit into account.The strategy is compatible with different countries’grid codes and prevents pulsating active power injection,in an unbalanced grid condition.Model predictive current controller is applied to handling rapid transients.During faults,the energy storage system maintains DC-link voltage,which causes voltage fluctuations to be eliminated,significantly.A fault ride-through strategy was proposed for PMSG-based wind turbines,neglecting fault characteristics,second,reaching maximum possible grid support in faulty grid conditions,while avoiding over-current and third,considerable reduction in energy storage system size and power rating.Inspiring simulations have been carried out through MATLAB/SIMULINK to validate the feasibility and competency of the proposed fault ride-through method and efficiency of the entire control system.
文摘风电大规模并网导致系统惯量严重降低,恶化了系统的频率稳定性。针对上述问题,该文结合非线性预测理论以及扩张状态观测理论(extended state observer,ESO)提出双馈风机参与电网频率调节的短期频率支撑方法。首先,建立与系统频率偏差和风机转速相关的目标状态方程,并计算不同控制目标量对应的预测阶;其次,根据非线性预测理论计算预测矩阵,对未来时刻状态跟踪误差进行预测,并求得非线性控制律;最后,引入扩张状态观测器对非线性控制律中的复杂李导数运算进行观测,减轻控制律所需的计算负担。通过MATLAB/SIMULINK搭建含风电系统进行仿真验证,结果表明,所提方法有效地改善了电网的频率响应,并且无需单独设计转速恢复环节,能够实现风机转速的自恢复。
文摘针对直驱式永磁同步风力发电系统风速多变、非线性和强扰动的问题,提出一种基于模糊控制和线性自抗干扰控制(Linear Active Disturbance Retection Control,LADRC)的混合控制方法。首先对线性自抗扰中的扩张状态观测器(Linear Extended State Observer,LESO)进行改进,提高对扰动观测的能力,同时利用模糊控制动态调整LADRC控制参数,增强系统的抗干扰能力和鲁棒性。仿真结果表明,与传统PI控制器相比,该方法能够更好地估计风速引起的转矩波动,准确跟踪额定转速,实现风能利用最大化。
文摘陆上风电全直流系统能有效解决谐波谐振、无功传输等问题,是未来风力发电系统的发展方向,其低电压穿越(low voltage ride through,LVRT)能力是系统稳定运行的保障。文中基于系统拓扑及其运行控制策略,剖析网侧电压跌落时聚集在陆上风电全直流发电系统直流环节的盈余功率,分析常规LVRT策略在风电全直流系统中的适用性。考虑电网对风电系统储能配置的要求,兼顾风电机组自启动特性提出利用电池储能存储低电压故障下直流母线的盈余功率实现LVRT的控制策略。在PSCAD/EMTDC仿真平台搭建陆上风电全直流发电系统模型,对所提策略进行仿真验证。结果表明,所提控制策略能够提升风电全直流发电系统的LVRT能力,促进直流母线电压的快速恢复;电池储能在故障期间吸收盈余能量,在风电机组自启动期间提供能量,提高了能量与储能的利用率。
