TL494开关电源毕业设计.doc

2011 沈阳理工大学XX上传
摘要
随着开关电源在计算机、通信、航空航天、仪器仪表及家用电器等方面的广泛应用, 人们对其需求量日益增长, 并且对电源的效率、体积、重量及可靠性等方面提出了更高的要求。开关电源以其效率高、体积小、重量轻等优势在很多方面逐步取代了效率低、又笨又重的线性电源。电力电子技术的发展,特别是大功率器件IGBT和MOSFET的迅速发展,将开关电源的工作频率提高到相当高的水平,使其具有高稳定性和高性价比等特性。开关电源技术的主要用途之一是为信息产业服务。信息技术的发展对电源技术又提出了更高的要求,从而促进了开关电源技术的发展。开关电源的高频变换电路形式很多, 常用的变换电路有推挽、全桥、半桥、单端正激和单端反激等形式。其中, 在半桥式变换器电路中, 变压器初级在整个周期中都流过电流, 磁芯利用得更加充分。本文介绍了一款基于PWM技术的半桥式开关稳压电源。给出了高频变压器、PWM控制及驱动电路的详细设计方法及设计思路,并用该方法设计了一台输出电压可自由调节的开关稳压电源。
关键词: PWM;半桥电路;开关电源
ABSTRACT
With the switch power source extensive use in the field puter , communicate by letter , aeronautics and astronautics , instrument appearance and domestic appliances etc., people increases by gradually to whose need amounts, have brought forward higher request to aspect such as power source efficiency , bulkfactor, and reliability. The switch power source is small with it's efficiency height , volume , weight makes light of to wait for advantage to have substituted the inefficient , both stupid and serious linearity power source in many aspects step by step. The electric power electronic technology development, specially high ponent IGBT and the MOSFET rapid development, enhancesthe switching power supply operating frequency to the quite high level, enable it to have the high stability and Gao paresand so on the characteristic. One of switching power supply technologymain uses is serves for the information industries. The information technology development also set a higher request to the power source technology, thus promoted the switching power supply technology power source high frequency alternation circuit form many, forms such as alternation circuit mon use having the push-pull , entire bridge , the bridge , only upright exciting and single end exciting partly on the contrary. Among them , be hit by in half bridge types converter circuit, the transformer is elementary in entire period all. This text introduce a half bridge switching mode power supply (SMPS) based on t