机电外文文献翻译--采用Atmel 89S51微控制器的风速风向测量系统【中文4420字】【PDF+中文WORD】

机电外文文献翻译--采用Atmel 89S51微控制器的风速风向测量系统【中文4420字】【PDF+中文WORD】,中文4420字,PDF+中文WORD,机电外文文献翻译,采用Atmel,89S51微控制器的风速风向测量系统【中文4420字】【PDF+中文WORD】,机电,外文,文献,翻译,采用,Atmel,89 【中文4420字】 采用Atmel 89S51微控制器的风速风向测量系统 Eunice Sophia K T 物理系 Sri Krishnadevaraya大学，Anantapuramu -515003，A.P.，印度 电子邮件：eunice.sophia@gmail.com Raghavendra Rao Kanchi SK大学工程与技术学院物理系主任，VLSI与嵌入式系统实验室教授， Anantapuramu - 515003，A.P.印度 电子邮件：kanchiraghavendrarao@gmail.com 摘要 - 本文介绍了围绕8051系列微控制器之一构建的简单仪器设计，用于测量瞬时风速和风向。 这个系统包括一个改进，但价廉的杯式风速计：戴维斯仪器6410感测上述两个风的参数。 处理系统的准确性在系统与风传感器接口之前被估计。 该软件采用C语言开发，数据每三秒钟在16x2液晶显示屏上显示。 然后将收集的数据绘制成圆形直方图进行分析。 所设计的系统由于其有效测量的原因而具有进一步发展和应用的潜力，这与标准读数相关。 关键词-AT89S51;风速计;LCD; 指南针点; 摩擦系数; 1、简介 即使技术日新月异，器件变得更加智能化，8051微控制器及其衍生产品仍然有望在各种应用领域找到应用。 目前的工作是关于测量两个主要的气象变量[1]，即在气象学，风资源评估研究，空中和水上航行，采矿和农业等许多应用中重要的风速和风向。 根据2011年3月的统计数据，印度仅安装了29％的风力发电总潜力，其中32％单独用于技术上[2]。 由于政府的目标是到2022年将风力发电量提高到60GW，显然印度更加专注于利用可再生能源发电用于清洁能源技术。 因此，该研究提出了可能提供潜在风资源评估的设计。 风一般是通过其标量组件进行测量和分析的; 与风向标或风向标的风速计和风向的风速。 对流层空气循环系统的年度性质，同时影响着一个地点的风速和风向[3]。 由于其线性和准确性，通常使用杯型和螺旋桨型旋转式风速计进行风速测量。 虽然所采取的测量通常是平均风资料，但瞬时风测量也很重要。 瞬时风速和方向数据有助于分析涡轮机和塔架的建造，而平均风速数据预测风力发电[4]。 由于功率与风速的立方功率成正比，因此风速测量的微小差异会大大影响发电量[5]。 所以准确的风速测量有助于计算安装风力涡轮机的良好可行性研究。 在用于将旋转速率转换为用于记录风速的适当电信号的不同机制[1]中，其中四种常用于使用直流发电机，交流发电机，电接触器和中断光束的换能器。 2、文献调查 以前与风速计和叶片接口进行风速和风向测量的工作考虑如下： Ivan Simeonov等[6]开发了一种短期天气预报嵌入式系统，其中风速传感器给出方波脉冲，每升高1公里就需要修正风速读数。 Michael Cosgrove等人[7]设计了一个超低成本的测风仪，用于风力发电的可行性调查。 在这种情况下，虽然磁簧开关在杯子的每次旋转时产生一个单一开关闭合的脉冲，但是开发了去抖动的算法。 Haci Can和Vedat M. Karsh [8]从事数据记录器的开发工作，使用基于8051的微控制器来测量风速和风向，也看到了对信号调理电路的需求。 Yahya S.H. Khraisat [9]在开发低成本的自动化系统的工作中，不断测量直流发电机类型的端口电压的天气参数，在与微控制器接口之前，需要进行信号调理。 Fouad Sh. Tahir等人[10]设计了一个基于个人电脑的数据采集系统来测量温度，风速和方向参数。即使当风速传感器为杯子的一次旋转而产生一个开关闭合周期时，在用于计算风速输出的电路中增加了DAC。 David Wekesa等[11]利用Atmel Atmega 32微控制器开发了一种自动化，低成本的风速和方向数据记录系统，该系统采用基于光电子的系统，可提供更高的每转脉冲数，即6至44 [12]。 Mehedi Al Emram等[13]也开发了基于光电子学的风速和风向测量系统。对于风速计的风杯的单次旋转产生多于一个的脉冲需要信号调节电路。 从上述考虑的工作中，产生正弦波的换能器需要额外的信号调节电路或具有去跳动电路的方波。 但是这个系统不需要信号调节，即使没有任何去跳动电路或去跳动算法或者使用DAC，传感器也很容易连接。通过使用摩擦系数从较低的高度推断风速的值来进行高度的修正。 3、硬件 A. 硬件描述 硬件主要由AT89S51单片机，风速传感器或风速计和LCD组成。 AT89S51是一款高性能的低成本微控制器。 它是一个具有4K字节在系统可编程闪存的8位微控制器。片上闪存使程序存储器可以在系统内或通过传统的非易失性存储器编程器重新编程。AT89S51的其他显着特点是：128字节的RAM，32条I / O线和2个16位定时器/计数器[14]。 所使用的风速计[15]具有对称地保持在竖直轴上的3个半球形杯。这种机械式风速计的设计在旋转过程中施加均匀的扭矩。 它是一种电气接触式的无源传感器，可以计算一段时间内的吹气量。 当磁簧开关接触到磁铁的影响时，设备不通电但发出脉冲。 簧片开关的安装使得每次旋转杯子时都会产生一次闭合。 传感器包括密封轴承，使用寿命长，能够抵御飓风的强风，虽然对起动阈值低的微风敏感。 传感器的规格说明范围和精度在风洞试验中得到验证。 杯子的材料重量轻，多功能和生态高效，其运行范围从小于1英里/小时到200英里/小时（英里）。杯子的旋转速度与吹风成正比。 与风速计相连的风向标是灵活的，响应速度快，指向风向。 叶片装有一个20k电位器。 在叶片的方向相应的电压被识别并且方向被相应地显示在LCD上。 雨刮器到终端的阻力与方位角完全一致。 方向与气象风向一致。 指向北方的叶片从0度开始，在罗盘上顺时针方向移动16点。 表一.罗盘指示 指南针指向 等级 N 348.75 – 11.25 NNE 11.25 – 33.75 NE 33.75 – 56.25 ENE 56.25 – 78.75 E 78.75 – 101.25 ESE 101.25 – 123.75 SE 123.75 – 146.25 SSE 146.25 – 168.75 S 168.75 – 191.25 SSW 191.25 – 213.75 SW 213.75 – 236.25 WSW 236.25 – 258.75 W 258.75 – 281.25 WNW 281.25 – 303.75 NW 303.75 – 326.25 NNW 326.25 – 348.75 B. 硬件设计 该设计采用传感器单元，随后是处理单元和显示单元。 图1.系统的设计 处理单元由一个ADC和AT89S51单片机以及5V电源电路组成。 显示单元有一个LCD，每3秒更新一次风速和风向信息。 通过使用来自函数发生器的与风传感器（即TTL兼容的方波）相似的输出来估算所设计的硬件的风速计算精度。 结果显示在下表中。 表二. 频率输入与显示输出的比较 给定的频率 (Hz) 计算值为2.25秒 LCD读取2.25 秒 3 6.75 7 5 11.25 11 10 22.5 23 20 45 45 30 67.5 67 40 90 89 65 146.25 145 78 175.5 174 85 191.25 190 98 220.5 219 100 225 224 106 238.5 237 上面比较的结果表明处理单元的输出与给定的频率很好地相关。 传感器发出的速度脉冲直接与微控制器连接，无需信号调节。 电路中使用的上拉电阻可确保单片机检测到的信号始终为高电平，除非传感器将其拉低。 该机制包括在2.25秒的采样周期内对脉冲进行计数，这与风速和风向测量的推荐采样平均次数1-5秒相一致[1]。 传感器输出的风向通过8位单通道ADC 0804与控制器连接。 微控制器被编程为根据ADC的值发出适当的方向。 功能电路图如下： 图2.电路框图 电路的照片如下所示。 图3.电路板上。 风速计被固定在一个2英尺的杆上，放在一个3层的建筑物上，用于露天测量。 传感器布置在空气自由流动的地方，但由于基础设施的限制，不能满足特定的要求，如固定在7英尺以上。 然而，在东北方向的一个不可避免的混凝土阻碍。 下图显示了传感器的所有侧面。 图4.放置在露天读数的风速计。 4、软件 该软件是使用KeilμVision5集成开发环境（IDE）以C语言开发的[16]。通过USB供电的传统8051存储器编程器将软件的十六进制文件加载到微控制器上。 该软件的流程图如下： 图5.风速和方向测量算法 五、结果与讨论 速度的风速测量以英尺/分钟的方向记录，液晶显示器上罗盘方向的缩写。 传感器对瞬间天气状况的反应似乎是灵活和准确的。 风向指向风向，风向很好地适应了风向的任何微小变化。 杯式风速计根据风向移动。 观察是在一天中的三个半小时内进行的。 每2分钟记录的读数平均为半个小时，并与印度斯里兰卡克里希纳德瓦拉亚大学（SKU）建立的气溶胶和大气研究实验室（AARL）实验室的声速测量读数的标准值进行比较。 10米高的标准读数和16米高的观测值列表如下： 表三. 标准和风速和方向的观测值 Hr 标准WS10m（m / s） 观测WS16m（m / s） 标准WDir 10m 观测WDir16m（指南针点） 16.5 1.5267 1.69875 68.5148 (ENE) ENE 17.0 1.8173 2.01168 76.0462 (ENE) ENE 17.5 1.8193 2.06756 92.9933 (E) E 下图显示了使用Oriana 4软件绘制的风玫瑰图： 图6. 16:00至16:30，ENE的风向平均值 图7. 16:30至17:00期间ENE的风向平均值 图8. 17:00至17:30 E期间的风向平均值 结果的几点是： ·在16小时到16小时30分钟的半小时内，大部分时间的风很大，占总数的50％，而东北偏东。 ·在16：30-17：00的时间段内，沿东 - 东北方向观测到更高的风速，从东方吹来高频风，甚至接下来的半小时。 ·由于大部分时间偏东风，西北侧的障碍物对观测影响很小，风向读数与标准读数恰好一致。 ·在16米处观测到的风速高于预期的10米处的风速。 ·死区误差从0o到5o，从355o到360o。 但后期的错误被编程淘汰了。 将10米高的风速标准值外推到观测值相关的高度16米。 为了外推，使用了Hellmann提出的幂律[17]。 方程是： v / v0 =（H / H0）α（1） 其中v是高度H处的速度，v0是高度H0处的速度（通常被称为10米高度），α是摩尔系数或Hellmann指数或风切变系数[18]。 这个系数是一个地点特定地形的函数，这个参数可以随着一天中的小时，一年的时间以及大气条件如空气密度而变化。 下面的表格[17]涉及各种景观的摩擦系数α。 表四. 不同景观的摩擦系数表 地面类型 摩擦系数（α） 湖泊，海洋和光滑的硬地 0.10 草原（地面） 0.15 高大的作物，树篱和灌木 0.20 森林茂密的土地 0.25 有一些树木和灌木的小镇 0.30 高层建筑物的城市地区 0.40 通过重写（1）计算摩擦系数α α=（ln（v）-ln（v0））/（ln（H）-ln（H0））（2） 根据2016年4月1日15时至15时15分的标准风资料，18米高的风速（v）为1.4704m / s，10米高的风速（v0）为1.39m / s。 从（2），这些值的摩擦系数是0.1。 但观测是在同一天从16Hr到17Hr 30min，当温度下降，摩擦系数增加的时候进行。 因此，接下来的两个摩擦系数即0.15和0.20被考虑用于从10m到16m的高度推断标准读数。 结果列表如下。 表五.外推的标准值和观测的风速图 S.No 时间(Hrs) WS(m/s) α=0.15 WS(m/s) α=0.20 观察 WS (m/s) 1 16.5 1.6382 1.6771 1.69875 2 17 1.9499 1.9964 2.01168 3 17.5 1.9521 1.9986 2.06756 α等于0.15和0.20的摩擦系数的外推标准风速读数与观测到的风速值强相关。 相关系数分别为0.99091和0.99089。 从图4可以看出，大部分时间的东风没有任何明显的障碍物。此外，观测到的风速值稍高一些，可以用来解释丘陵，建筑物等发生的风速加速。风会遇到阻塞[17]。 然而，电力管理对风力资料的长期观测使用相对较短。 6.结论 利用AT89S51微控制器和Davis风速仪6410开发的系统测量实时风速和风向显示的结果相当准确，这得到了当天同一时间SKU大气研究实验室的标准值的证实。所获得的强相关系数表明该系统是可靠的。 参考 [1]美国环境保护局（EPA）。 “监管建模应用气象监测指南”，2000年2月。EPA-454 / R-99-005。 [2] http://www.infraline.com/reportdetails/112/Wind-Power-Outlook-in- 印度2015.htm [3] http://green-power.com.pl/en/home/wiatr-i-jego-pomiar-w-energetyce- wiatrowej / [4] http://www.homepower.com/articles/wind-power/design- installation / understanding-wind-speed [5] http://www.wwindea.org/technology/ch01/en/1_4.html [6] I. Simeonov，H. Kilifarev，R. Llarionov，“短期天气预报嵌入式系统”，计算机系统和技术国际会议论文集（CompSysTech'06），2006年。 [7] M. Cosgrove，B. Rhodes，J. Scott，“风力发电可行性调查的超低成本测井风速仪”，研究门，2007年1月。 [8] H. Can，V. M. Karsh，“利用基于8051的微控制器进行多点风速和方向测量和数据记录”，美国科学杂志，157：2482-2488,2007。 [9] Yahya S. H. Khraisat，“在约旦设计无线气象站”，加拿大科学和教育中心，第一卷。 2012年1月5日，1日。 [10] F. S. Tahir，A. M. Salman，J. K. Mohammed，W. K. Ahmed，“风速，方向和温度测量的数据采集系统”，Journal of Engineering， 18，没有。 11，第1229-1236页，2012年11月。 [11] D.W Wekesa，J.N. Kamau，J.N. Mutuku，“用于风速和方向测量的校准数据记录仪表系统”，工程创新基础研究期刊， 1（3），第53-57页，2013年6月。 [12] S. Pindado，J. Cubas，F. Sorribes-Palmer，“风杯测风仪，风能产业的基本气象仪器。在IDR / UPM研究所进行研究“，Sensors， 2014年8月14日，第21428-21452页。 [13] http://documents.mx/documents/a-microcontroller-based-system-for- determining-instantaneous-wind-speed-and.html [14] AT89S51 Datasheet.pdf。 [15]戴维斯风速仪6410 Datasheet.pdf。 [16] http://www.keil.com/c51/pk51kit.asp F.Banuelos-Ruedas，C.A. Camacho，S. Rios-Marcuello。 “在一个地区的风能资源评估中使用的方法”。可用：www.intechopen.com [18] Firas A. Hadi，“诊断风速外推的最佳方法”，国际电气，电子和仪器工程高级研究杂志。第一卷.2015年10月 Wind Speed and Direction Measurement System Using Atmel 89S51 Microcontroller Eunice Sophia K T Department of Physics,Sri Krishnadevaraya University,Anantapuramu-515003,A.P.,India.Email: Raghavendra Rao Kanchi Professor,VLSI&Embedded System Laboratory,Department of Physics and Principal,College of Engineering and Technology,SK University,Anantapuramu 515003,A.P.,India.Email: AbstractThis paper presents a simple instrumentation design built around one of the 8051 family microcontroller to measure instantaneous wind speed and wind direction.This system includes an improved,yet an inexpensive cup anemometer:Davis Instruments 6410 to sense the above said two wind parameters.The accuracy of the processing system is estimated prior to the interfacing the system with the wind sensor.The software is developed in C language and the data is displayed on 16x2 LCD for every three seconds.The collected data is then plotted in circular histogram for analysis.The system designed has the potential to be further developed and be used for in applications for the reason of its effective measurement which correlated well with the standard readings.KeywordsAT89S51;Anemometer;LCD;Compass points;Friction coefficient;I.INTRODUCTION Even as the technology improves day by day and the devices get smarter,8051 microcontroller and its derivatives still hold the promise of being a sufficient one in finding applications in various application fields.The present work concerns the measurement of two of the primary meteorological variables 1 namely wind speed and direction which is important in many applications like meteorology,wind resource assessment studies,air and water navigation,mining and agriculture.As per the statistics on March 2011,only 29%of the total gross potential for wind power development was installed in India of which 32%alone is technically usable 2.Since the government targets for to enhance the wind power production to 60GW by 2022,its clear that India is more focused to produce electricity using renewable sources towards clean energy technology.The study therefore presents a design which could possibly provide a potential to be used in wind resource assessments.Wind is commonly measured and analyzed with its scalar components separately;wind speed with anemometer and wind direction with wind vane or weather vane.The annual nature of the system of air circulation in the troposphere,affects both the wind speed and direction at a location 3.Due to their linearity and accuracy,rotational anemometers of cup and propeller type are commonly used for wind speed measurements.Though the measurements taken are usually of mean wind data,instantaneous wind measurement is also important.Instantaneous wind speed and direction data assist in analyzing the build of the turbine and tower whereas the mean wind speed data predicts wind power generation 4.Minor differences in the wind speed measurement affects the power generation greatly since the power is proportional to the cube power of the wind speed 5.So accurate wind speed measurements helps in calculating good feasibility studies for installing wind turbines.Among the different mechanisms 1 used to convert the rate of rotations to an appropriate electrical signal for recording the wind speed,four of them are commonly used which employ transducers of type DC generator,AC generator,the electrical contact and the interrupted light beam.II.LITERATURE SURVEY Previous works relating to interfacing the cup anemometer and the vane for the wind speed and direction measurement are considered as follows:Ivan Simeonov et al 6 developed an embedded system for short-term weather forecast in which the wind speed transducer gave square wave pulses whose wind speed readings needed correction for every 1 kilometer increase in altitude.Michael Cosgrove et al 7 designed an ultra-low cost logging anemometer intended for feasibility surveys of wind power generation.In this case,although the magnetic reed switch produced one pulse for single switch closure per revolution of the cups,an algorithm for debouncing was developed.Haci Can and Vedat M.Karsh 8 work in the development of a data logger using 8051 based microcontroller to measure wind speed and direction,also saw the need for signal conditioning circuitry.Yahya S.H.Khraisat 9 in his work of developing a low-cost automated system that continuously measured weather parameters the terminal voltage from DC generator type,saw the need of signal conditioning before interfacing with the microcontroller.Fouad Sh.Tahir et al 10 designed a data acquisition system based on personal computer to measure temperature,wind speed and direction parameters.Even when the wind speed transducer produced one switch closure cycle for a single rotation of the cups,a DAC was added in the circuitry for the calculation of wind speed output.David Wekesa et al 11 developed an automated,low-cost system of wind speed and direction data logger using Atmel Atmega 32 microcontroller which used optoelectronics-based system that give higher pulse rates per revolution i.e.6 to 44 12.Mehedi Al Emram et al 13 also developed a system for measuring wind speed and direction based on optoelectronics.The production of more than one pulse for a single revolution of the wind cups of the anemometer needed signal conditioning circuitry.From the above works taken into consideration,the transducers that produce the sinusoidal wave needed an additional circuit for signal conditioning or a square wave with a de bounce circuit.But this system doesnt need signal conditioning and the sensor is easily interfaced even without any de bounce circuit or de bounce algorithm or use of a DAC.The correction in the altitude is carried out by extrapolating the values of wind speed from a lower height using friction coefficient.III.HARDWARE A.Description of the Hardware The hardware primarily consists of the AT89S51 microcontroller,wind sensor or anemometer and LCD.AT89S51 is a high performing low-cost microcontroller.It is an 8-bit microcontroller with 4K bytes of In-system programmable flash memory.The on-chip flash enables the program memory to be reprogrammed either in-system or by conventional nonvolatile memory programmer.The other salient features of AT89S51 are:128 bytes of RAM,32 I/O lines and two 16bit timers/counters 14.The anemometer 15 used has a 3 hemispherical cups symmetrically held on to the vertical shaft.This design of mechanical type anemometer exerts uniform torque during revolutions.It is a passive transducer of electrical contact type that calculates the amount of air blowing in an interval of time.The device is not powered but sends out a pulse when the reed switch makes a contact on influence of the magnet.The reed switch is mounted so that it makes a single closure per revolution of the cups.The sensor includes sealed bearings for long life and can stand up to hurricane force winds although being sensitive to a light breeze with low starting threshold.Specifications of the sensor state that the range and accuracy were verified in the wind tunnel tests.The material of the cups is of light weight,versatile and eco-efficient with its operating range from less than 1 mph to over 200 miles per hour(mph).The rate of rotation of the cups is proportional to the wind blow.The weather vane that comes attached with the anemometer is flexible and has quick response to align itself pointing to the direction in which the wind blows.The vane is fitted inside with a 20k potentiometer.The vanes direction corresponding voltage is recognized and direction is displayed accordingly on the LCD.The resistance from the wiper to the terminal is completely linear with azimuth.The directions are in accordance with the meteorological wind direction.The vane pointing north starts with 0 degrees and moves clockwise through 16 points on compass rose.TABLE I.COMPASS DIRECTIONS Compass points Degree N 348.75 11.25 NNE 11.25 33.75 NE 33.75 56.25 ENE 56.25 78.75 E 78.75 101.25 ESE 101.25 123.75 SE 123.75 146.25 SSE 146.25 168.75 S 168.75 191.25 SSW 191.25 213.75 SW 213.75 236.25 WSW 236.25 258.75 W 258.75 281.25 WNW 281.25 303.75 NW 303.75 326.25 NNW 326.25 348.75 B.Hardware design The design employs the sensor unit followed by the processing unit and the display unit.Fig.1.Design of the system The processing unit consists of an ADC and AT89S51 microcontroller along with the 5V power supply circuit.The display unit has a LCD that updates the wind speed and direction information every 3 seconds.The hardware designed was estimated for wind speed calculation accuracy by using a similar output as of the wind sensor i.e.a TTL compatible square wave,from a function generator.The results are shown in the table below.TABLE II.COMPARISON OF FREQUENCY INPUT AND DISPLAYED OUTPUT Frequency given(Hz)Calculated value for 2.25 sec LCD read for 2.25 sec 3 6.75 7 5 11.25 11 10 22.5 23 20 45 45 30 67.5 67 40 90 89 65 146.25 145 78 175.5 174 85 191.25 190 98 220.5 219 100 225 224 106 238.5 237 The results compared above shows that the output from the processing unit relates well with the frequency given.The speed pulse sent by the sensor was directly interfaced with the microcontroller without the need for signal conditioning.A pull-up resistor used in the circuit ensures the signal detected by the microcontroller is always high except when the sensor pulls it low.The mechanism includes counting the pulses in a sampling period of 2.25seconds which is in accordance with the recommended sampling averaging times of 1-5 seconds for wind speed and wind direction measurements 1.The wind direction output from the sensor is connected to the controller through ADC 0804 which is a 8-bit and single channeled.The microcontroller is programmed to send out the appropriate direction according to the value at ADC.The functional circuit diagram is as follows:Fig.2.Block diagram of the circuit The photograph of the circuit is shown below.Fig.3.Circuit on board.The anemometer was fixed to a 2 foot pole and placed atop a 3-storey building for the open air measurements.The sensor was arranged at a location where there is free flow of air but could not meet the specific requirements like fixing it above 7 feet due to infrastructural constraints.However,there was an unavoidable concrete obstruction to the northeastern side of the placement.The picture below shows all the sides of the sensor.Fig.4.Anemometer placed for open air readings.IV.SOFTWARE The software was developed in C language using Keil Vision5 Integrated Development Environment(IDE)16.The hex file of the software was loaded on to the microcontroller by USB powered conventional 8051 memory programmer.The flowchart of the software is as follows:Fig.5.Wind speed and direction measurement algorithm.V.RESULTS AND DISCUSSIONS Wind measurement of speed is recorded in mph and direction by the abbreviation of the compass direction on LCD.The sensors response to the instant weather conditions appear to be flexible and accurate.The vane heeded well to any slight change in the wind direction by pointing itself into the direction of the wind.The cup anemometer moved in accordance with the wind flow.The observations were taken for three half-an-hours during the day.The readings noted for every 2 minutes were averaged to half an hour and compared with the standard values of the sonic anemometer readings from the Aerosol and Atmospheric Research Laboratory(AARL)lab set up by ISRO at Sri Krishnadevaraya University(SKU).The standard readings at 10m height as well as the observed values at 16m height are tabulated below:TABLE III.STANDARD AND OBSERVED VALUES OF WIND SPEED AND DIRECTION Hr Standard WS10m(m/s)Observed WS16m(m/s)Standard WDir10m Observed WDir16m(Compass points)16.5 1.5267 1.69875 68.5148(ENE)ENE 17.0 1.8173 2.01168 76.0462(ENE)ENE 17.5 1.8193 2.06756 92.9933(E)E Wind Rose graphs plotted using Oriana 4 software are shown below:Fig.6.Wind direction resultant mean at ENE for 16:00 to 16:30.Fig.7.Wind direction resultant mean at ENE during 16:30 to 17:00.Start Include suitable header files Define ports Initialize LCD Set Timer 1 to count 8-bit value Start counting pulses for the sampling period and stop the counter Display the wind run on LCD Read the wind direction digital output from ADC Select the wind direction according to the analog voltage and display on LCD Do it for ever Fig.8.Wind direction resultant mean at E during 17:00 to 17:30 A few points of the results are:?Easterly wind blew for most of the time during the half an hour between 16hr to 16hr 30 min forming 50%of the total while the resultant mean is towards East-North east.?During the 16:30 to 17:00 time period,higher wind speeds were observed along East-Northeast and East direction with high frequency wind blowing from the East even for next half an hour.?The obstruction on north-western side impacted little on the observations due to easterly wind blowing for most of the time and the wind direction readings coincided exactly with that of the standard readings.?The wind speeds as observed at 16m are higher as expected with the wind speed measured at 10m.?The dead band error is present from 0o to 5o and from 355o to 360o.But the latter part of the error was eliminated by programming.The standard values of wind speed at height of 10m are extrapolated to the height of 16m at which the observed values relate.For extrapolation the power law 17 proposed by Hellmann is used.The equation is v/v0 =(H/H0)(1)Where v is the the speed at height H,v0 is the speed at height H0(frequently referred to as a 10-meter height)and is the friction coefficient or Hellmann exponent or wind shear coefficient 18.This coefficient is a function of the particular topography at a site,and this parameter can vary by the hour of the day,time of the year and with atmospheric conditions such as air density.The table 17 shown below relates the friction coefficient for a variety of landscapes.TABLE IV.FRICTION COEFFICIENT TABLE FOR DIFFERENT LANDSCAPES.Landscape type Friction coefficient()Lakes,ocean and smooth hard ground 0.10 Grasslands(ground level)0.15 Tall crops,hedges and shrubs 0.20 Heavily forested land 0.25 Small town with some trees and shrubs 0.30 City areas with high rise buildings 0.40 The friction coefficient is calculated by rewriting(1),as =(ln(v)ln(v0)/(ln(H)ln(H0)(2)According to the standard wind data from 15Hrs to 15.5Hrs on 1st April,2016 the wind speed(v)at 18m height is 1.4704m/s and at 10m height,the wind speed(v0)is 1.39m/s.From(2),the friction coefficient for these values is 0.1.But the observations were taken on the same day from 16Hr to 17Hr 30min which was toward evening when the temperature fall and the friction coefficient increase.So the next two friction coefficients i.e.0.15 and 0.20 were taken into consideration for extrapolating the standard reading from 10m to 16m height.The results are tabulated as below.TABLE V.EXTRAPOLATED STANDARD VALUES AND OBSERVED WIND SPEED READINGS S.No Time of the day(Hrs)WS(m/s)=0.15 WS(m/s)=0.20 Observed WS(m/s)1 16.5 1.6382 1.6771 1.69875 2 17 1.9499 1.9964 2.01168 3 17.5 1.9521 1.9986 2.06756 The extrapolated standard wind speed readings for both the friction coefficients of equal to 0.15 and 0.20 strongly correlated with the observed values of wind speed.The correlation coefficients are 0.99091 and 0.99089 respectively.The easterly wind blowing for most of the time did not have any apparent obstructions as can be seen from Fig.4.Moreover,a little higher observed wind speed values can be accounted for the wind speed acceleration that occurs over hills,buildings etc(when the wind encounters an obstruction)17.The power management however is relatively short for the use of long term observations of wind data.VI.CONCLUSION The system developed using AT89S51 microcontroller and Davis Anemometer 6410 to measure real-time wind speed and wind direction showed fairly accurate results which were corroborated by the standard values from the Aerosol and Atmospheric Research Laboratory at SKU,taken during the same hours on the same day.The strong correlation coefficients obtained showed that the system can be a reliable one.References 1 USA Environmental Protection Agency(EPA).“Meteorological Monitoring Guidance for Regulatory Modeling Applications”,February 2000.EPA-454/R-99-005.2 http:/ 3 http:/green-.pl/en/home/wiatr-i-jego-pomiar-w-energetyce-wiatrowej/4 http:/ 5 http:/www.wwindea.org/technology/ch01/en/1_4.html 6 I.Simeonov,H.Kilifarev,R.Llarionov,“Embedded system for short-term weather forecasting”,Proceedings of International Conference on Computer Systems and Technologies(CompSysTech06),2006.7 M.Cosgrove,B.Rhodes,J.Scott,“Ultra-low-cost Logging Anemometer for Wind Power Generation Feasibility Surveys”,Research Gate,January 2007.8 H.Can,V.M.Karsh,“Multipoint Wind 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