Design of step-down high-power high-voltage switching power supply based on microcontroller

High-power DC high-voltage power supply is widely used in industry and military field. This paper presents a design scheme of high-power and high-voltage adjustable feedback DC power supply. The output voltage of TL494 can be adjusted from OV to 900V by using the double voltage rectification technology and the step-down chopper circuit, and by changing the internal integrated operational amplifier reference voltage of TL494. The output characteristics of this power supply are good and the voltage is stable and adjustable, the output ripple voltage is lower than 40 mV, the ripple coefficient is lower than 0.094%, the load adjustment rate is 4.26%. The model has the advantages of strong universality, wide adjustable output range and low cost.