發(fā)布時間：2018-03-29 20:24

  本文選題：離子風(fēng)　切入點：電暈放電　出處：《江蘇大學(xué)》2017年碩士論文

【摘要】：近年來,隨著全球制造業(yè)對產(chǎn)品“低碳化、高效化、環(huán)保化”的日益重視,“綠色光源”LED在照明領(lǐng)域得以廣泛應(yīng)用。尤其是功率型LED的出現(xiàn),滿足了諸多照明應(yīng)用場合對光源的苛刻要求。但是,受到發(fā)光原理和自身結(jié)構(gòu)的限制,LED芯片內(nèi)部極易產(chǎn)生熱量堆積,尤其是高驅(qū)動電流下的功率型LED,工作性能及使用壽命更是受到結(jié)溫的嚴(yán)重影響,致使當(dāng)前不少場合對功率型LED的應(yīng)用都停留在實驗室研究階段,而難以實現(xiàn)產(chǎn)業(yè)化。隨著制造工藝和封裝技術(shù)的不斷推進,LED芯片內(nèi)部熱阻已得到明顯降低。因此,選擇一種高效的外部散熱方案成為改善功率型LED熱管理問題的關(guān)鍵。本研究針對傳統(tǒng)散熱方案應(yīng)用過程中的缺點,提出了一種基于電暈放電原理的離子風(fēng)散熱方案,設(shè)計加工出了一款結(jié)構(gòu)可調(diào)的離子風(fēng)散熱裝置。通過試驗探尋了離子風(fēng)發(fā)展過程中的伏安特性變化規(guī)律,并從中得出影響離子風(fēng)特性的主要因素包括電源極性、發(fā)射極與接收極的結(jié)構(gòu)、放電間距等。這些因素對離子風(fēng)發(fā)生器的起暈電壓、工作電壓的可調(diào)范圍、離子風(fēng)風(fēng)速以及功耗等諸多性能有直接影響。因此,本研究搭建了一套測試系統(tǒng),進行了離子風(fēng)發(fā)生器的散熱應(yīng)用試驗。試驗以功率型LED芯片組達到穩(wěn)定工作狀態(tài)時的引腳溫度、芯片結(jié)溫、系統(tǒng)熱阻等為控制目標(biāo),在進行散熱系統(tǒng)搭建時,根據(jù)發(fā)熱器件的結(jié)構(gòu)及發(fā)熱特點進行放電電極分布的優(yōu)化設(shè)計,探討了不同的離子風(fēng)散熱方式對功率型LED的散熱效果。研究結(jié)果表明,離子風(fēng)散熱方案可有效緩解功率型LED使用過程中結(jié)溫過高的問題,離子風(fēng)的產(chǎn)生大大提高了散熱裝置的極間換熱系數(shù),當(dāng)散熱系統(tǒng)與LED芯片在常溫下同時處于工作狀態(tài)時,芯片引腳溫度可保持在50℃以下。與自然對流狀態(tài)下相比,在離子風(fēng)的作用下,系統(tǒng)熱阻顯著減小。選擇針狀電極作為離子風(fēng)發(fā)生器的發(fā)射極,并對發(fā)射極輸入負(fù)極性高壓,可降低放電過程的起暈電壓,增大工作電壓的可調(diào)范圍,同時還能夠提高整個散熱裝置的工作穩(wěn)定性。研究針對LED芯片組所設(shè)計的“一字型”針電極陣列,是幾種針電極陣列中綜合散熱效果較好的設(shè)計方案。
[Abstract]:In recent years, with the increasing attention of the global manufacturing industry to "low carbonization, high efficiency and environmental protection", the "green light source" LED has been widely used in the field of lighting, especially the emergence of power type LED. It meets the harsh requirements of light source in many lighting applications. However, due to the principle of luminescence and the limitation of its own structure, it is easy to generate heat accumulation inside the LED chip. Especially, the performance and service life of power type LEDs under high driving current are seriously affected by junction temperature, which results in the application of power type LED in laboratory research stage. However, it is difficult to realize industrialization. With the continuous development of manufacturing technology and packaging technology, the internal thermal resistance of LED chips has been significantly reduced. Choosing an efficient external heat dissipation scheme is the key to improve the thermal management of power type LED. In this paper, a scheme of ion wind heat dissipation based on corona discharge principle is proposed to solve the shortcomings of the traditional heat dissipation scheme. A structure adjustable ion wind heat dissipation device is designed and manufactured. The variation law of volt-ampere characteristics during the development of ion wind is explored through experiments, and the main factors influencing the ion wind characteristics include the polarity of power supply, from which we can find out that the main factors affecting the ion wind characteristics include the polarity of the power supply. The structure of emitter and receiver, the distance between discharge and so on. These factors have direct influence on the corona voltage of ion wind generator, the adjustable range of working voltage, the wind speed of ion wind, power consumption and so on. In this study, a testing system was set up, and the heat dissipation test of the ion wind generator was carried out. The control targets were the pin temperature, chip junction temperature and system thermal resistance when the power LED chipset reached the stable working state. When the heat dissipation system is built, the optimum design of discharge electrode distribution is carried out according to the structure and characteristics of the heating device, and the heat dissipation effect of different ion air cooling modes on the power type LED is discussed. The scheme of ion wind heat dissipation can effectively alleviate the problem of excessive junction temperature in the use of power type LED. The generation of ion wind greatly increases the inter-polar heat transfer coefficient of the heat dissipation device. When the cooling system and the LED chip are simultaneously working at room temperature, The chip pin temperature can be kept below 50 鈩，

本文編號：1682703