Design of digital Control High-voltage DC Power Supply

In order to detect electro-osmosis flow conveniently, a digital small-power high-voltage DC (HDC) power supply based on DSP is introduced which is fully controllable and fast response. The structure of the main circuit is Buck converter which is controlled by the voltage PWM control technology. A voltage feedback closed loop is used in the circuit, in which the digital optical fiber is used for isolation and transmission. Addition to data collection, the DSP controller calculates the duty cycle, which is based on the feedback signal, so that the output voltage can be real-timely traced and monitored. Consequently, the principle of whole system including control circuit and main circuit is described. Finally, the feasibility of the proposed approach is verified on a simulink model with 220V input and 4000V/1mA output. The results show that the HDC system meets the need of automatically detect electroosmosis experiment and gives full play to the convenience of digital power and control.