为提高太阳能的利用率，以ATmega8单片机为控制核心，设计了一套光电跟踪与视日运动轨迹跟踪互补控制的双轴太阳跟踪器。该跟踪器在晴天时，利用光敏电阻采集光强判断太阳位置,控制步进电机实现光电跟踪；在阴天时，采集时钟器件PCF8583的时间信息,计算当前太阳位置来实现视日运动轨迹跟踪。实验表明：该太阳跟踪器能在不同天气状况下对太阳进行较准确地跟踪，能量接收效率提高了30%，达到充分利用太阳能的目的。 Abstract: To improve the utilization rate of solar energy，a kind of solar tracking controller which effectively combined the sun angle tracking and photo electric tracking based on ATmega8is designed.In the sunny days，the solar tracking con-troller determines the sun's position by using photosensitive resistances to collect light intensity and control stepper motors to achieve photo electric tracking，n cloudy days，it collects clock chip PCF8583time information to calculate the current position of the sun and achieve the sun angle tracking.Experimental results show the solar tracking controller accurately tracks the sun in different weather conditions，improves received energy efficiency by30%and reaches the purpose of full use of solar energy.
上传时间： 2013-10-15
上传用户：urgdil
针对材料试验机等设备中要求测量或控制材料拉伸或压缩的位移，一般采用光电轴角编码器检测位置信号，输出正交编码脉冲信号。若采用其他方法检测位置信号，必然导致电路设计复杂，可靠性降低。因此，提出一种基于LS7266R1的电子式万能材料试验机设计方案。给出了试验机中的控制器工作原理，LS7266R1与单片机的接口硬件设计，以及主程序软件流程图。巧妙地把力量传感器，位移传感器等机械运动状态的压力或拉力以及位置坐标，变成了电压信号和电脉冲数字信号，供A/D测量和LS7266R1计数，从而实现了独立完成材料试验控制或通过PC机串口命令完成材料试验控制。 Abstract: Aiming at the requirement that the displacement of the tension and compression always be tested and controlled in the equipement such as material testing machine. The position signal was tested by photoelectric axial angle coder. Therefore， the paper proposes the design of electronic universal testing machine design based on LS7266R1. If the position signal detected by other methods， will inevitably lead to the circuit design complexity， reliability decreased. The work theory of the controller， the hardware interface design between LS7266R1 and single chip， and the flow chart of main program， are presented in this paper. The signal of the compression or tension power and displacement at working， which tested by power sensor and displacement sensor especially， is changed into electric voltage and electric pulse numerical signals. And these signals can be tested by A/D and counted by LS7266R1. Finally the test of the material properties can be controlled by itself， or controlled by the COM command of PC.
上传时间： 2013-11-01
上传用户：yl1140vista
介绍了电力操作电源与智能电池巡检系统的特点，给出了一种基于超低功耗单片机MSP430 F149针对中小型变电站自动化运行的专用设备的基本设计原理及实现方法，最后给出了详细硬件构成和软件实现。该系统能满足中小型变电站安全、可靠、自动运行的要求，并通过与上位机的串行通信实现变电站的远程管理和控制。 Abstract: The characters of the intelligent battery data logging system of the electric operation power are introduced.The basic design principle and the implemented methods of the special equipment which only designed for the middle or small transformer substation based on MSP430F149 are prescribed. Finally, the hardware block diagram and the software flow chart are also given. The function that the system finally needs to realize can basically meet with the middle or small transformer substation’s satisfy, reliably,and automatic running.And it can also realize the transformer substation long-distance management and control by serial communicating with the host computer.
上传时间： 2013-11-24
上传用户：黄华强
为解决输油管道温度压力参数实时监测的问题，设计了以C8051F930单片机作为控制核心的超低功耗输油管道温度压力远程监测系统。现场仪表使用高精度电桥采集数据，通过433 MHz短距离无线通信网络与远程终端RTU进行通信，RTU通过GPRS网络与PC上位机进行远程数据传输，在上位机中实现数据存储和图形化界面显示，从而实现输油管道温度压力参数的实时监测和异常报警。经实验证明，该系统的12位数据采集精度满足设计要求，漏码率小于1%，正常工作时间超过5个月，能实时有效地监测输油管道的温度压力参数，节省大量人工成本，有效预防管道参数异常造成的经济损失和环境污染。 Abstract: In order to solve the problems on real-time monitoring of pipeline temperature and pressure parameters， the ultra-low power remote pipeline temperature and pressure monitoring system was designed by using the single chip processor C8051F930 as the control core. The high-precision electric bridge was used in field instruments for data collection， the 433MHz short-range wireless communication network was used to make communication between field instrument and RTU， the GPRS was used by the RTU to transmit data to the PC host computer， and the data was stored and displayed in the PC host computer， so the real-time monitoring and exception alerts of pipeline temperature and pressure parameters were achieved. The experiment proves that the system of which error rate is less than 1% over five months working with the 12-bit data acquisition accuracy can effectively monitor the pipeline temperature and pressure parameters in real time， it saves a lot of labor costs and effectively prevents environmental pollution and economic losses caused by abnormal channel parameters.
上传时间： 2013-11-06
上传用户：cuibaigao
基于PIC单片机的脉冲电源:设计了一种金属凝固过程用脉冲电源。该电源采用PIC16F877作为主控芯片，实现对窄脉冲电流幅值的检测，以及时电流脉冲幅值根据模糊PID算法进行闲环控制。使用结果表明：该电源的输出脉冲波形良好，电流幅值稳定，满足合金材料凝固过程的工艺要求且运行稳定可靠。关键词：脉冲电源；PIC16F877单片机；模糊PID；闲环控制 Abstract：A kind of pulse power supply was designed which uses in the metal solidification process ．．I11is power supply used PIC16F877 to take the master control chip reali on to the narrow pulse electric current peak-to-peak value examination，carried on the closed-loop control to the electric current pulse peak-to-peak value basis fuzzy PID algorithm．The use result indicated ，this power supply output se profile is good，and the electric current peak-to-p~k value is stable，It satisfies the alloy material solidification process the technological requirement and movement stable reliable，Key words：p se po wer supply；PIC16F877single-chip microcontroller；f r PID；closed-loop control
上传时间： 2013-10-26
上传用户：xcy122677
Calculation of the Differential Impedance of Tracks on FR4 substrates There is a discrepancy between calculated and measured values of impedance for differential transmission lineson FR4. This is especially noticeable in the case of surface microstrip configurations. The anomaly is shown tobe due to the nature of the substrate material. This needs to be considered as a layered structure of epoxy resinand glass fibre. Calculations, using Boundary Element field methods, show that the distribution of the electricfield within this layered structure determines the apparent dielectric constant and therefore affects theimpedance. Thus FR4 cannot be considered to be uniform dielectric when calculating differential impedance.
上传时间： 2013-10-18
上传用户：masochism
This a very simple Yee algorithm 3D FDTD code in C implementing the free space form of Maxwell s equations on a Cartesian grid. There are no internal materials or geometry. The code as delivered simulates an idealized rectangular waveguide by treating the interior of the mesh as free space/air and enforcing PEC (Perfect electric Conductor) conditions on the faces of the mesh.
标签： implementing algorithm Maxwell simple
上传时间： 2015-05-14
上传用户：水中浮云
he LPC932 can be used to create a Pulse Width Modulated PWM signal. That s an analog signal, with only 2 discrete levels, for example 0V and 5V and a constant period. The current value of this signal at a certain poiTnt of time is proportional to its Duty Cycle. That s the High Time during one period divided by the period. It can also be calculated as the average value during a particular period. That means after low pass filtering, (e.g. RC circuit) the signal becomes analog, with an actual value controlled by the microcontroller. The PWM functionality enables the LPC932 to control for example the speed of DC motors or the brightness of electric lighting.
标签： signal Modulated analog create
上传时间： 2015-05-14
上传用户：CHINA526
water temperature control system uses the Single Chip Microcomputer to carry on temperature real-time gathering and controling. DS18B20, digitized temperature sensor, provides the temperature signal by "a main line". In -10～+85℃ the scope, DS18B20’s inherent measuring accuracy is 0.5 ℃. The water temperature real-time control system uses the electricity nichrome wire carring on temperature increiseament and operates the electric fan to realize the temperature decrease control. The system has the higher measuring accuracy and the control precision, it also can complete the elevation of temperature and the temperature decrease control.
标签： temperature Microcomputer real-tim control
上传时间： 2015-12-10
上传用户：nairui21
This submission includes the presentation and model files that were used in delivering a webinar on 12-15-05 that covered the topic of modeling Hybrid electric Vehicles. Hybrid electric vehicles (HEVs) have proven they can substantially improve fuel economy and reduce emissions. Because HEVs combine an electric drive with the internal combustion engine (ICE) in the powertrain, the vehicle?s kinetic energy can be captured during braking and transformed into electrical energy in the battery. The dual power source also means that the ICE can be reduced in size and can operate at its most efficient speeds.
标签： presentation submission delivering includes
上传时间： 2015-12-23
上传用户：zl5712176
