What is the classification and principle of switching power supply?
People's switching power supply technology field is the side of the development of related power electronic devices, the side of the development of switching inverter technology, the two promote each other to promote the switching power supply each year to more than double-digit growth rate in the direction of light, small, thin, low-noise, high-reliability, anti-jamming development. Switching power supply can be divided into two categories of AC / DC and DC / DC, DC / DC converter has now achieved modularity, and design technology and production processes at home and abroad have matured and standardised, and has been recognised by users, but the modularity of the AC / DC, because of its own characteristics make the process of modularity, encountered in the modular process, a more complex technology and manufacturing process issues. The following are two types of switching power supply structure and characteristics are described.
DC/DC converter
DC/DC conversion is to convert a fixed DC voltage into a variable DC voltage, also known as DC chopper. Chopper works in two ways, one is the pulse width modulation Ts unchanged, change the ton (universal), the second is the frequency modulation, the ton unchanged, change the Ts (easy to produce interference).
Simply put, the working principle of switching power supply is.
1. AC power input rectified and filtered into DC; 2.
2. Through the high-frequency PWM (Pulse Width Modulation) signal control switching tube, the DC added to the primary switching transformer.
3. Switching transformer secondary induction of high-frequency voltage, rectified and filtered to supply the load.
4. The output part is fed back to the control circuit through a certain circuit to control the PWM duty cycle to achieve the purpose of stable output.
