反激电源开关管电压尖峰的形成原理  

The Principle of the Formation of Voltage Spikes in the Flyback Power Switch

作　　者：李志雨 LI Zhiyu(Shenzhen Dade Aviation Technology Co.,Ltd.,Shenzhen 518100,China)

机构地区：[1]深圳达德航空科技有限公司,广东深圳518100

出　　处：《通信电源技术》2024年第3期115-117,共3页Telecom Power Technology

摘　　要：反激型开关电源在开关管关断时刻会出现高频率高幅值的电压尖峰,如果不加以处理不仅会加重电磁干扰,还会增加开关管的电压应力。基于此,详细论述开关管关断电压尖峰形成的原理,推导得出尖峰电压的表达式,并利用仿真软件MathCAD可计算得出尖峰电压的最大值和稳态值,为开关管选型和尖峰吸收电路的设计提供理论指导。Flyback switching power supply in the switch off moment will appear high frequency and high amplitude voltage spike,if not dealt with will not only aggravate the electromagnetic interference,but also increase the voltage stress of the switch tube.Based on this,the principle of switching off voltage spike formation is explained in detail,the expression of spike voltage is derived,and the maximum value and steady state value of spike voltage can be calculated by using the simulation software MathCAD,which provides theoretical guidance for the selection of switching tubes and the design of spike absorbing circuits.

关 键 词：电压尖峰 漏感 结电容 二阶振荡 

分 类 号：TM41[电气工程—电器]