PZN-PNN-PZT压电陶瓷材料在能量收集装置中应用

发布时间：2018-04-15 04:36

本文选题：PZT + PZN　；参考：《南京航空航天大学》2015年硕士论文

【摘要】：利用自然界清洁且储量丰富的风能,结合具有高能量密度的压电材料,设计出为小型电子器件和无线传感网络节点供电的能量收集装置已经受到越来越多的关注。但是能量转换效率的低下始终制约着压电能量收集装置的广泛应用。主要原因有二:第一、压电材料作为整个压电能量收集装置的核心,本身必须满足大功率能量输出的要求,即应该具有较高的能量转换系数值d33·g33;第二、压电能量收集装置的结构对提升能量转换效率起着至关重要的作用。本论文从材料和结构两方面入手进行改进,以获得高能量转换系数的压电材料及高机电转换效率的压电能量收集装置,从而解决小型风力压电发电装置效率和输出功率低的问题。本文首先在现有的成分点0.8Pb(Zr0.5Ti0.5)O3 0.1PZN 0.1PNN的基础上,通过改变Zr:Ti含量比即0.8Pb(ZrxTi1-x)O3 0.1PZT 0.1PNN,确定实验成分点,制备陶瓷样品。通过对比陶瓷样品在这些成分点的XRD图谱,发现明显的“三方—四方”转变过程,找到相变点。在Zr:Ti=52:48及Zr:Ti=50:50得到了具有两个d33·g33值较高的成分点,对应的d33·g33值分别为20019×10-15m2/N和17500×10-15 m2/N。这样不仅找到了高能量密度的成分点,而且深化了人们对该体系材料相变特性的认识。然后,基于“共振可以产生最大的能量输出、冲击可以激发出所有频率的振动、一阶弯曲振动振幅和份额最大”等振动学基本规律,设计并成功搭建了“弹性球-冲击”的基本冲击实验平台,研究了诸参数对弹性球冲击压电振子俘能单元能量输出特性的影响规律。通过实验发现对于冲击型压电振子,铜片和陶瓷片的任一尺寸改变都会对输出电压产生一定影响;当其他尺寸一定时,铜片的厚度在一定范围内对输出的电压有重要影响。在此基础上,设计了两款利用冲击产生机械振动的旋转型压电俘能装置。其中,水平旋转式能量收集装置采用内多边形结构,通过改变压电振子的数量控制压电悬臂梁组成的内多边形的大小,通过尺寸设计就可将每次弹性球冲击的位置限制在一阶弯曲共振点附近,即有效地将冲击区域限制在压电悬臂梁的一阶弯振模态上,从而大大提高了输出功率和发电效率。垂直旋转式的旋转轴采用垂直水平面安置,叶片安装方式类似达里厄(darrieus)型风车。其优点在于全风向旋转,不用对风向,因而具有高的风能利用率;此外,弹性球在旋转隔板作用下撞击压电振子端部,形成冲击并反弹,在隔板与压电振子形成的空腔内交替作用于隔板和压电振子,解决了大风速下由于离心力产生的停转问题;而且,多自由球和多振子设置,形成机械能向电能的并行转换,有利于提高输出功率。
[Abstract]:Using clean and abundant natural wind energy and piezoelectric materials with high energy density, the design of energy collection devices for small electronic devices and wireless sensor network nodes has attracted more and more attention.However, the low efficiency of energy conversion has always restricted the wide application of piezoelectric energy collection devices.The main reasons are as follows: first, as the core of the whole piezoelectric energy collection device, the piezoelectric material itself must meet the requirements of high power energy output, that is, it should have a higher energy conversion coefficient (D33 g 33).The structure of piezoelectric energy collection device plays an important role in improving energy conversion efficiency.In this paper, material and structure are improved to obtain piezoelectric materials with high energy conversion coefficient and piezoelectric energy collection device with high electromechanical conversion efficiency.In order to solve the problem of low efficiency and output power of small wind power piezoelectric power generation device.Firstly, on the basis of 0.8Pb(Zr0.5Ti0.5)O3 / 0.1PZN 0.1PNN, an experimental composition point was determined by changing the Zr:Ti content ratio, that is, 0.8Pb(ZrxTi1-x)O3 / 0.1PZT (0.1PNN), to prepare ceramic samples.By comparing the XRD spectra of ceramic samples at these composition points, the obvious "tri-tetragonal" transition process was found and the phase transition point was found.At Zr:Ti=52:48 and Zr:Ti=50:50, two higher d33g33 components were obtained, corresponding d33g33 values were 20019 脳 10-15m2/N and 17500 脳 10-15 m2 / N, respectively.In this way, not only the component points with high energy density are found, but also the understanding of the phase transition characteristics of the system is deepened.Then, based on the fundamental laws of vibration, such as "resonance can produce maximum energy output, shock can excite vibration of all frequencies, the amplitude and share of first-order bending vibration is the largest".The basic impact experimental platform of "elastic sphere impact" was designed and successfully built. The influence of various parameters on the energy output characteristics of piezoelectric vibrator was studied.It is found that any change of the size of the copper and ceramic plates will have a certain effect on the output voltage for the shock piezoelectric vibrator, and the thickness of the copper sheet will have an important effect on the output voltage in a certain range when the other dimensions are fixed.On this basis, two rotating piezoelectric energy capture devices are designed to generate mechanical vibration by impact.Among them, the horizontal rotary energy collection device adopts the inner polygon structure. By changing the number of piezoelectric vibrators, the size of the inner polygon of the piezoelectric cantilever beam is controlled.Through the dimension design, the position of each impact of elastic sphere can be limited to the first order bending resonance point, that is, the impact area can be effectively confined to the first order bending vibration mode of piezoelectric cantilever beam, thus the output power and generation efficiency can be greatly improved.The vertical rotary shaft is installed in a vertical horizontal plane, and the blade is installed in a similar manner to the Darieu darrieus-type windmill.The advantages are that the whole wind direction is rotated and the wind direction is not used, so that the wind energy utilization rate is high; in addition, the elastic ball impinges on the end of the piezoelectric vibrator under the action of the rotating diaphragm to form an impact and bounce back.The cavity formed by the diaphragm and piezoelectric vibrator alternately acts on the diaphragm and piezoelectric vibrator, which solves the problem of stopping due to centrifugal force at high wind speed; moreover, the setting of multiple free balls and oscillators forms a parallel conversion of mechanical energy to electrical energy.It is propitious to increase the output power.
【学位授予单位】：南京航空航天大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TM282;TM619

【参考文献】