為提高太陽能的利用率,以ATmega8單片機為控制核心,設計了一套光電跟蹤與視日運動軌跡跟蹤互補控制的雙軸太陽跟蹤器。該跟蹤器在晴天時,利用光敏電阻采集光強判斷太陽位置,控制步進電機實現光電跟蹤;在陰天時,采集時鐘器件PCF8583的時間信息,計算當前太陽位置來實現視日運動軌跡跟蹤。實驗表明:該太陽跟蹤器能在不同天氣狀況下對太陽進行較準確地跟蹤,能量接收效率提高了30%,達到充分利用太陽能的目的。 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.
上傳時間: 2013-10-15
上傳用戶:urgdil
介紹一種采用單片機技術和基站器件EM4095的手持式低頻RFID讀卡器方案。首先對整個系統框架進行說明,然后介紹主要功能模塊的設計,給出了各模塊的原理圖。重點描述了基站器件EM4095的性能參數和功能原理,最后描述了該系統的主程序流程圖。 Abstract: In this paper,a handheld RFID reader based on MCU and EM4095 is introduced.At first,the configuration of this system is explained.Then the design of main modules and schematic documents are particularly presented.The parameters and principle of the chip EM4095 are introduced in detail. At last,the main software flow is given
上傳時間: 2013-10-18
上傳用戶:windypsm
為了解決磁放大器性能測試過程中,需要對其供給不同數值恒定電流的問題,設計了一種基于DAC7512和單片機的數控恒流源系統。該系統采用AT89C51作為主控器件,將計算機發送的電流控制字命令轉換為D/A轉換器控制字,通過模擬SPI通信接口,寫D/A控制字到DAC7512,從而控制其輸出相應數字電壓值,經差動縮放電路、電壓/電路變換電路和功率驅動電路,最后輸出恒定電流。實驗結果表明,恒流源輸出電流調節范圍為-45~+45 mA、精度為±0.1 mA,分辨率達0.024 4 mA,具有應用靈活,外圍電路簡單,可靠性高的特點。該數控直流恒流源也可為相關產品的測試系統研發提供參考。 Abstract: In order to solve the need to supply different values constant current for the magnetic amplifier in testing process, numerical control constant current source system was designed based on DAC7512 chip and microcontroller technology. The system used the AT89C51 as the main chip, which can convert the current control word from computer into to D/A control words. And the system wrote D/A control word into the DAC7512 chip to control the output voltage value by the SPI communication interface, which can output corresponding constant current figures by scaling circuit, the V/I converter and power drive circuit. Experimental results show that the current source output current adjustment range is -45~+45mA, accuracy is ± 0.1mA, and resolution ratio is 0.024 4mA
上傳時間: 2014-12-27
上傳用戶:invtnewer
針對目前采用的熱敏電阻測量方法,提出了采用單總線數字式溫度傳感器DS18B20和單片機組成的新型溫度測量儀。介紹DS18B20的結構和工作原理,以及單總線工作原理,給出了由Mega8單片機和DS18B20構成的單總線溫度測量儀的硬件電路及軟件流程圖。經試驗基于單總線器件DS18B20的溫度測量儀,具有測量準確、測溫范圍寬、體積小、控制方便等優點。 Abstract: This paper brings forward a new temperature meter composed of 1-Wire temperature sensor DS18B20 and MCU which has advantage of the thermistor. In the article, the DS18B20's structure and controlling principles are introduced and hardware circuit and software diagram of the temperature meter are given.After been tested,the temperature meter has the advantages of accurate measurement, wide temperature range, small volume and convenient controlling.
上傳時間: 2013-10-31
上傳用戶:hzy5825468
摘要:設計并制作了一種基于溫度梯度驅動的液滴傳輸芯片,以實現對微液滴傳輸的精確控制.介紹了驅動原理和工藝流程,分析了仿真和實驗結果.該芯片利用溫度梯度下液滴表面形成的表面張力梯度來傳輸液滴,采用玻璃作為襯底,Ti為電阻加熱器,Au為電極,PECVD氧化硅為介質層,碳氟聚合物為疏水層,實現了器件制作.芯片采用開放式結構,制作工藝簡單,操作方便.測試結果表明,驅動功率為0.38W時,去離子水和硅油的傳輸速率分別達到0.1mm燉s和1mm燉s.關鍵詞:微液滴;溫度梯度;表面張力梯度;電阻加熱器;開放式結構
上傳時間: 2013-10-29
上傳用戶:ukuk
摘要:介紹了以AT89C51單片機為控制中樞,利用EXB841專用驅動及保護器件對功率模塊絕緣柵雙極晶體管(IGBT)進行驅動與保護的變頻器設計方法。介紹了EXB841在應用中的一些原則性事項,闡述了AT89C51單片機產生正弦脈寬調制(SPWM)脈沖的算法及編程方法,描述了異步電動機在變壓變頻(VVVF)調速時的近似機械特性及變頻調速方式下的主要對策以及帶有反饋信號的輸出控制方式的實現,最后給出了變頻調速控制下的實際數據。關鍵詞:IGBT;驅動;逆變;變壓變頻
上傳時間: 2013-11-07
上傳用戶:kristycreasy
宏晶STC90C58AD系列單片機器件手冊
上傳時間: 2013-10-15
上傳用戶:ZZJ886
STC8051系列單片機器件手冊
上傳時間: 2014-12-27
上傳用戶:shen_dafa
STC12C5410AD系列單片機器件手冊
上傳時間: 2013-11-11
上傳用戶:stewart·
STC12C5628AD系列單片機器件手冊
上傳時間: 2013-11-19
上傳用戶:linlin