Theoretical Comparative Energy Efficiency Analysis of Dual Axis Solar Tracking Systems

This paper developed a theoretical model substantially based on the principle that only the normal component of solar radiation is actually converted into electrical energy. This theoretical model helped to predict minimum and maximum daily energy gain (compared to static PV system tilted with certain angle) when using dual axis PV solar tracking systems, at any given location on earth without prior experimental data. Based on equations derived from model, minimum and maximum energy gain is computed and summarized in tables of minimum and maximum. Furthermore, the model equations could be used to set up future experimental studies related to the matter.

Theoretical and Experimental Quantification of Solar Radiation through a Tracking System

This work deals with the estimation of solar radiation through a solar tracker aimed at evaluating the effect of solar tracking on the solar deposit in Burkina Faso. Using a two-axis solar tracking system, we experimentally measured solar radiation at our Joseph KI-ZERBO University site and compared it with that obtained by a numerical simulation run using Fortran programming software based on a mathematical model by Brichambaut. The results obtained from the mathematical and experimental studies show that, with a solar tracker, on a clear-sky day, solar irradiation is between 800 W·m−2 and 1000 W·m−2 between about 8 a.m. and 4 p.m., i.e. a duration of 8 hours of insolation. Analysis of the numerical and experimental results shows very good quantitative and qualitative agreement, with an average relative error of 18%.

Three-degree-of-freedom Parallel Manipulator to Track the Sun for Concentrated Solar Power Systems

In concentrated solar power（CSP） generating stations, incident solar energy is reflected from a large number of mirrors or heliostats to a faraway receiver. In typical CSP installations, the mirror needs to be moved about two axes independently using two actuators in series with the mirror effectively mounted at a single point. A three degree-of-freedom parallel manipulator, namely the 3-RPS parallel manipulator, is proposed to track the sun. The proposed 3-RPS parallel manipulator supports the load of the mirror, structure and wind loading at three points resulting in less deflection, and thus a much larger mirror can be moved with the required tracking accuracy and without increasing the weight of the support structure. The kinematics equations to determine motion of the actuated prismatic joints in the 3-RPS parallel manipulator such that the sun＇s rays are reflected on to a stationary receiver are developed. Using finite element analysis, it is shown that for same sized mirror, wind loading and maximum deflection requirement, the weight of the support structure is between 15% and 60% less with the 3-RPS parallel manipulator when compared to azimuth-elevation or the target-aligned configurations.

A Sun Tracking System Design for a Large Dish Solar Concentrator

Energy crisis promotes the development of renewable energy, especially the solar energy. Sun tracking system proposed in this paper is such a device for efficiency improvement. This closed loop tracking system with two axis sun tracking method is controlled by a programmable logic controller (PLC) and is used for a large dish solar collector. A combination tracking mode combined active and passive tracking methods used in the design make the tracker efficient whatever the circumstances. Two stepper motors and two reduction boxes move the device towards the sun with chain transmission. Besides sun tracking, the system also has functions of overheat monitoring, wind speed monitoring and measurement of illumination.

Ka频段车载遥感站天线伺服控制系统设计

针对Ka频段7.3 m车载遥感站天线高精度标校、窄波束跟踪等应用需求,提出一种多数据源融合的跟踪控制方法。该方法采用双GPS/北斗定北和太阳标校相结合的角度校准方法,提高了天线捕获概率,解决了车载站天线难捕获以及车载站转场后伺服高精度角度标校的问题;综合利用天线系统中的接收机跟踪误差数据、程序跟踪点位数据、外部引导角度数据和天线实时角度测量数据,通过自适应加权最小二乘方法进行数据融合跟踪,提高了车载站天线伺服控制系统跟踪精度和跟踪性能。测试结果表明,组合标校方法实现天线外场角度标校精度优于0.02°;多源融合跟踪与单一数据源跟踪相比,伺服控制系统跟踪误差减小了30%以上,跟踪精度优于1/15个波束宽度。验证了组合标校和多源融合跟踪方法的有效性,可用于指导大口径高频段遥感接收天线伺服控制系统设计。

基于4级放坡光电传感器的太阳跟踪系统设计

为提高太阳能利用装置的采光效率,设计了一种4级放坡四棱台光电传感器,分析了其跟踪范围和跟踪精度,并以此为基础设计了太阳跟踪系统的硬件部分和软件部分。试验结果表明:光电传感器粗跟踪装置的跟踪范围远远超过了一年当中方位角、高度角变化范围最大的夏季,能够满足对太阳在高度角和方位角大范围跟踪的需要。通过对软件流程的设计,采用5 min修正一次角度的循环方式,能够满足精跟踪装置跟踪精度的需求。通过光照强度对比试验,验证了太阳跟踪系统在粗、精两级跟踪模式下,太阳能利用装置的采光效率相比休眠模式采光效率提高了57.02%。该设计为太阳跟踪系统光电传感器跟踪范围的扩大和跟踪精度的提高提供了参考。

入射偏角对非跟踪复合抛物面聚光器性能影响

为了降低复合抛物面聚光器对跟踪精度的要求,提高其在集热过程中的光热转化能力,探究入射偏角对新型复合抛物面聚光器非跟踪工况时光热性能的影响机制。理论分析该聚光器在集热过程中的能量转化关系,并利用光学仿真软件TracePro研究入射偏角对聚光器光学性能的影响规律;在此基础上搭建非跟踪复合抛物面聚光器性能测试试验台,在实际天气条件下测试分析聚光器光热性能随径向入射偏角的变化规律。结果表明:当光线正入射时,聚光器的光线接收率与聚光效率分别为100%和83.42%;当径向入射偏角α为16°时,该聚光器的光线接收率与聚光效率分别为53.00%和44.82%;当轴向入射偏角β为30°时,光线接收率与聚光效率分别为88.74%和74.42%;在空气流速为3.7 m/s时,聚光器的最高出口温度与瞬时集热量分别为31.3℃和782.8 W,分别比聚光器接收上偏10°和下偏10°入射辐射时提高了3.7、6.1℃和131.0、217.9 W;该聚光器接收正入射辐射时的平均光热转化效率为77.45%,比接收上偏10°和下偏10°入射辐射的平均光热转化效率高42.14%和52.97%。

基于物联网远程监控的太阳能定向跟踪系统设计

设计了一种基于物联网远程监控的太阳能定向跟踪系统,分别对太阳能定向跟踪系统本体和远程监控系统进行了设计与开发,采用离线和实时控制两种方式,通过监控数据计算当前的太阳高度角和方位角,调整光伏板的倾角,从而提高太阳能光伏板的发电率。对该装置设备层的太阳能定向跟踪系统本体采用框架式结构设计,并通过模糊PID算法对跟踪装置电机进行调控;对应用层的远程监控系统采用B/S架构设计,使用MQTT协议与云平台进行数据交互,用户可直接通过浏览器访问监控系统,实现太阳能定向跟踪系统的远程状态检测、实时控制、数据管理等功能。经测试,用户能通过该监控系统控制和监控太阳能定向跟踪系统的运行,满足太阳能定向跟踪系统远程监控的要求,系统具有较高的实用性。

一种适用于监控系统中弱光条件的光伏逐日系统

太阳能是当前具有代表性的绿色能源之一,固定式光伏支架由于安装方向固定,光伏面板无法始终朝向太阳,而光伏逐日系统的监控系统对于跟踪其性能和确保高效运行至关重要。因此,该文提出一种基于监控系统中可适用于弱光条件下的光伏逐日系统,采用信捷XC3 PLC承担其主要程序控制任务,利用光敏传感器收集各个方向的光强差值,通过程序计算出最佳光照角度,进而驱动电机调整为最佳照射角度,将云量和天气预报数据集成到监测系统中,以预测阳光变化并相应地辅助逐日系统运行。大幅提高光电转化率。

基于凸轮控制的太阳能循迹小车

设计了一种基于凸轮控制的太阳能循迹小车。介绍了小车的机械结构和传动机构,分析了循迹原理,并给出了稳压电路和充电电路。对太阳能循迹小车进行试验测试,确认小车运行良好,能够实现特定轨迹的行驶。

多模式风光火储系统多目标优化调度

风光发电具有波动性和随机性,大规模并入电网影响电力系统的稳定性、安全性。建立考虑火电机组深度调峰和电储能寿命折损成本的风光火储能源系统模型,提出负荷跟踪、功率平滑两种出力模式。以风光火储各子系统出力为决策变量,建立了一种以风光火储能源系统运行成本最低、新能源消纳最多、环保性最好为目标的优化调度模型。通过NSGA-Ⅱ算法分别求解两种模式的调度模型,得到帕累托解集,最后基于AHP决策方法确定最优调度方案,实现能源系统出力跟踪负荷、能源系统功率平滑的功能,降低风光发电并入电网带来的冲击。仿真计算结果表明两种模式下的调度策略可以提高风光火储能源系统的经济性,增强新能源消纳能力,减少污染性气体排放,验证了优化调度模型的有效性。

New Linkage with Linear Actuator for Tracking PV Systems with Large Angular Stroke

This paper focuses on the development of an optimized photovoltaic tracking system involving low-cost, relative simple mechanisms, with linear actuators able to insure strokes comparable with those resulted when using gear rotary actuators. Starting with a rhombus linkage, with a linear actuator on the diagonal used for the elevation motion till 90°, a new performance solution is generated. This new linkage allows large angular strokes by using an asymmetric rhombus and an eccentrically positioned linear actuator. The paper can be divided in three main parts. Firstly the kinematical modeling of the new linkage is addressed, which permits the establishing of the linkage dimensions according to two adjustable parameters （k2, k5）. Using the resulted correlations, in the second part the linkage synthesis algorithm is developed; the steps followed in this algorithm are presented in a numerical application considering a tracked PV platform, where the azimuthal vertical movement is obtained with the new proposed rhomboidal linkage. In the last part of the paper an analysis is done with the aim of determining the PV platform tracking efficiency （which represents the ratio between the received and the available beam solar energy） using the new linkage, in the meteorological conditions of Brasov, Romania implementation site.

Complete Solution of Sun Tracking for Heliostat

A general solution of sun tracking for an arbitrarily oriented heliostat towards an arbitrarily located target on the earth is published. With the most general form of solar tracking formulae, it is seen that the used azimuthelevation, spinning-elevation tracking formulae etc. are the special cases of it. The possibilities of utilizing the general solution and its significance in solar energy engineering are discussed.

基于STM32F103C8T6光电跟踪的多功能太阳能光伏花

为充分利用新能源并解决景区照明能耗高、观赏性低、光源固定等问题,设计一种基于STM32F103C8T6光电跟踪的多功能太阳能光伏花。采用光电跟踪法收集尽可能多的太阳能并将其转换为电能储存在锂蓄电池中,以为装饰灯和其他模块供电。同时,设计了L298N电机驱动模块,控制受光模块与小车以反方向转向运动,解决由小车方向导致太阳能电池板同向运动的问题。用户可通过蓝牙控制光伏花的开花、闭花和移动。在相同环境下分别测试了视日轨迹跟踪和光电跟踪对太阳能的吸收效率,结果表明光电跟踪法在成本控制和对太阳能的吸收效率上表现更优。利用光电跟踪法可充分利用太阳能,不易受突发天气影响。

光伏跟踪电机的分数阶自抗扰控制方法

针对光伏跟踪系统运行时负载端产生高频振荡以及在运行过程中遇到的极端天气等不可控因素导致的系统失调、鲁棒性降低等问题,根据光伏跟踪系统中负载反馈模型实现速度控制,设计了一种改进型分数阶自抗扰控制器。该控制器采用函数优化后的分数阶跟踪微分器和线性组合的分数阶扩张状态观测器来抑制高频振荡,加快负载端速度响应并提高系统抗干扰能力。实验结果表明,改进后的分数阶自抗扰控制器使得抑制了负载端39.60%的高频振荡,系统稳态时间缩短了20.83%,转速波动减少了36.97%,有效改善了系统控制性能,提高了系统鲁棒性。

多元智能园林培育系统的研究与应用

为了更好地提升园林培育的智能化程度,实现了一款创新的多元智能园林培育系统,旨在为不同习性的植物量身定制生长条件。系统通过多样化的传感器技术融合,精准调控培育环境,如土壤湿度监测、光照调节和太阳能追踪,为植物提供最适宜的生长环境。方案研究和实现了条件决策的数据分析算法,能够智能分析植物需求并自动化调整培育条件,不仅显著提升了植物的生长效率,也为园林培育行业的智能化发展开辟了新的思路。

Photovoltaic Sensor for the Solar Battery Guidance on the Sun Based on GeS:Sb Layered Crystals

Photovoltaic tracking sensor monitoring the position of the sun in the sky was developed on the basis of GeS:Sb layered crystals. The operating principle of this sensor is based on the phenomenon of photovoltaic effect in GeS:Sb crystals;the magnitude and sign of generated photo-emf depend on the position of the light probe relative to the ohmic contacts, deposited on (001) surface of the crystal.

基于Fourier拟合的光伏跟踪系统设计

[目的]为提高光伏支架的发电效率,以基于Fourier拟合算法的视日运动轨迹光伏跟踪器为研究设计对象。[方法]借助MATLAB分析了传统视日运动轨迹算法的跟踪精度情况,更进一步地在此基础上提出了精度更优的8阶傅里叶拟合视日运动轨迹跟踪算法,并结合GNSS定位技术,得出太阳实时运行轨迹。系统设计以STM32单片机作为微处理器,采用6轴加速度传感器,通过重力矢量在其轴上的投影确定光伏跟踪支架的实时倾斜度,以此二者建立跟踪支架三维运行模型,通过分析太阳光线在支架上的余弦效应即可得到电机需要运行的动作角。同时为解决晨昏时刻光伏组件间的阴影遮挡问题,系统增加逆跟踪算法。并考虑到大规模机组的应用,提出主从电机同步控制策略。[结果]傅-2里叶拟合算法拥有更高的跟踪精度,精度可达到10数量级,高于传统算法一个数量级。同时采用逆跟踪技术可节约24.3%光伏阵列用地面积,大幅提高了土地利用率。[结论]本研究采用更为精准的视日运动轨迹跟踪模型,较好地解决了太阳辐射利用的余弦效应,提升了电站的发电效率,实现了安全高效绿色能源体系的建设,促进了我国“双碳”目标的推进与达成。

分水闸门采用直流供电系统的设计研究

水利输水工程中采用风光互补直流供电的闸门测控系统已在国内诸多输水工程项目中开展了试验性应用,系统采用直流直驱方式进行闸阀门监控,系统配备视频监控、水情、水力监测、信息化传输等功能的系统化输水测控方案已得到较为成熟的应用,并具备推广应用条件,系统的新能源供电和直流直驱闸门测控方案可有效解决水利工程存在的市电供应成本高、安全环保成本大、管理维护困难等突出问题,为有效推进水利信息化建设提供了基础保障,对智慧水利建设提供了技术支撑,为分析风光互补供电的直流闸门测控系统特征,在工程实际项目中进行针对性地系统设备选型,通过实际系统工程建设、试验运行,表明风光互补供电的闸门测控系统可实现稳定运行要求,在特定环境和设计配置使用条件下有必要进行针对性设计选型。

基于Boost电路的光伏系统MPPT变工况分析

近年来,太阳能因其卓越的环保特性、可再生能源的特质以及可持续发展的重要性,成为了能源领域备受关注的研究和实践焦点。然而,太阳能的高效利用受多种气象因素的影响,包括温度、光照强度和天气变化等。这些因素对太阳能系统的性能和能源产出构成了重大挑战。研究了一种提高太阳能利用率的方法,即通过调节Boost电路的占空比来调节太阳能电池板的输出电压,实现对太阳能电池板的变工况最大功率点追踪,从而应对温度、光照强度等天气条件的变化。