垂直轴阻力差型风机的气动制动研究

风能是一种自然界取之不尽,用之不竭的的清洁能源。随着传统能源的日益消耗,以及随之而来的环境污染日趋严重,风能利用成为各个国家节能减排的工作重点之一。
风力发电技术,经过长时间的技术积累和市场应用,成为人们利用风能的最主要方式。与此同时借助风力机发热成为了继风力发电之后的又一个很有发展前景的方向。和风力发电机一样,风力发热系统同样面临在各种工况下的控制问题,而制动系统首当其冲,成为了风力机安全与可靠性问题极为重要的一环。除了在风力机的旋转主轴上安装各式各样的机械制动器,人们还 发了空气动力制动系统。而且空气动力制动系统由于其自身的使用特点,成为现代风力机制动系统中必不可少的组成部分。
本文主要研究了垂直轴阻力差型风力机在极限工况下的气动制动问题,有效的降低风力机所承受的风压,维护风力机本身的安全。借鉴水平轴风力机的变桨机构,通过变桨功能来完成功率的调节和空气动力的制动原理,在垂直轴风力t几上通过调节叶片的角度来调整风能利用率,达到制动之目的。
本文针对国内垂直轴阻力差型风机气动制动系统研究不足的问题,具体的给出了一种垂直轴阻力差型风力机可转动叶片通过安装扭转弹簧来控制和调整叶片偏转角度的方案。目的是降低叶片在极限工况下的受力面积,从而保证叶片在排解掉一部分风压后,保证叶片的结构安全。设计了满足在极限工况下,控制叶片最大偏转角度的扭转弹簧。
并且本文也将风力机与永磁涡流发热机进行了匹配实验研究,通过实验研究验证了叶片气动制动应用的可行性,为垂直轴风力机气动制动奠定了基础。
Abstract
Wind energy is a inexhaustible clean energy. With the increasing consumption ofconventional energy,environment pollution get more and more serious consequently, windenergy utilization has become one of the priorities of energy saving all aroud the world. Aftera long period of technology accumulation and market application,wind electricity has becomethe main way of wind energy utilization. At the same time, wind heating system become apromising direction . Meanwhile,wind heating system is also facing controlling problems atthe variety conditions. The braking system bear the brunt of the wind turbine safety issues.Mechanical brake can be installed on the wind turbine's rotating spindle. Aerodynamicbraking system is also developed for brake system. And because of its features, aerodynamicbraking system has become the integral part of the modern wind turbine.The main work of this thesis is to achieve a pneumatic brake for differential resistancetype of vertical axis wind turbine in the limit conditions. Reducing exposure to the windeffectively, wind turbine maintenance and safety has been promised. According to thehorizontal axis wind turbine pitch organization,the aerodynamic braking function can berealized. So the vertical axis wind turbine can also adjust the angle of the blades to completethe utilization of wind energy .
In this paper, a rotatable blade system of resistance type vertical wind turbine is given,torsion spring can achieve good control of the blade angle. The purpose is to reduce the windpressure on the blade and ensure the structural safety of the bladeat the limit condition.Torsion spring is designed to meet the limit conditions, the maximum rotating angle is undergood control . And wind turbine has been matched with permanent magnet eddy currentheating machine, experimental study to verify the feasibility of the blade aerodynamic brakingsystem. All these works have laid a good foundation for future research and applications ofwind turbine Pneumatic brake.
Keywords: Wind Energy Utilization, The Rotatable Blades, Torsion Spring, Pneumatic
Brake,Matching Problem.