The ruins of GugeKingdom arefound in Ngari,atthe westernmostpoint of the Tibet Plateau. Itabuts India in the west andsouth,Kashmir in the north-west and Xinjiang in the north.Screened by mountains onthree sides,it is ...The ruins of GugeKingdom arefound in Ngari,atthe westernmostpoint of the Tibet Plateau. Itabuts India in the west andsouth,Kashmir in the north-west and Xinjiang in the north.Screened by mountains onthree sides,it is tucked awayat an elevation of 4,000meters. This is a part of theworld which is very dry.TheZhangzhung Culture existedbefore the kingdom wasfounded.展开更多
一类改进的最优转矩(optimal torque, OT)法通过扩大风力机最大功率点跟踪(maximum power point tracking, MPPT)过程中的不平衡转矩来提升转速跟踪能力,进而捕获更多风能。然而,此类方法在提高风能捕获效率的同时会造成电磁转矩的频繁...一类改进的最优转矩(optimal torque, OT)法通过扩大风力机最大功率点跟踪(maximum power point tracking, MPPT)过程中的不平衡转矩来提升转速跟踪能力,进而捕获更多风能。然而,此类方法在提高风能捕获效率的同时会造成电磁转矩的频繁波动,导致风力机传动链载荷显著提升。针对这一问题,文中研究发现在风速变化下补偿转矩引起的额外电磁转矩波动是产生上述现象的主要原因。为此,文中提出一种考虑载荷影响的风力机加速OT法,在风速变化时通过利用恒转矩过渡阶段抑制额外的电磁转矩波动,提升MPPT过程中的转速跟踪能力,从而实现在提升风力机风能捕获效率的同时尽可能避免载荷增大。最后,仿真结果验证表明,文中所提加速OT法不仅可以提升不同风况下的风能捕获效率,而且能够有效抑制传动链载荷的上升。展开更多
文摘The ruins of GugeKingdom arefound in Ngari,atthe westernmostpoint of the Tibet Plateau. Itabuts India in the west andsouth,Kashmir in the north-west and Xinjiang in the north.Screened by mountains onthree sides,it is tucked awayat an elevation of 4,000meters. This is a part of theworld which is very dry.TheZhangzhung Culture existedbefore the kingdom wasfounded.
文摘一类改进的最优转矩(optimal torque, OT)法通过扩大风力机最大功率点跟踪(maximum power point tracking, MPPT)过程中的不平衡转矩来提升转速跟踪能力,进而捕获更多风能。然而,此类方法在提高风能捕获效率的同时会造成电磁转矩的频繁波动,导致风力机传动链载荷显著提升。针对这一问题,文中研究发现在风速变化下补偿转矩引起的额外电磁转矩波动是产生上述现象的主要原因。为此,文中提出一种考虑载荷影响的风力机加速OT法,在风速变化时通过利用恒转矩过渡阶段抑制额外的电磁转矩波动,提升MPPT过程中的转速跟踪能力,从而实现在提升风力机风能捕获效率的同时尽可能避免载荷增大。最后,仿真结果验证表明,文中所提加速OT法不仅可以提升不同风况下的风能捕获效率,而且能够有效抑制传动链载荷的上升。
