Design of High Voltage DC Power Supply for Negative Ion Air Purifier

At present, the negative ion air purifier is the mainstream of improving indoor air quality. The most critical part is the negative ion generator, and the core component of the negative ion generator is the high voltage DC power supply, which determines the quality and efficiency of the purifier to a large extent. To this end, this paper designs a 500 W low-power high-voltage DC power supply, under the mains input, through EMI filtering and rectification to form about 310 V DC, and then through the use of new field resistance technology, high-performance IGBT-FGH40N60SMD switching tube composed of half bridge circuit and output rectification to increase the voltage to −5 kV. The design introduces a new generation of high performance DSPIC33EP64GS504 as a controller, after feedback and four rules PID regulation, output pulse width adjustable PWM signal, and then drive IGBT switching tube, voltage, current double closed-loop control successfully. The power supply is controllable and adjustable, the hardware topology is relatively simple, the voltage accuracy is high, the ripple is low, the efficiency is up to 92.2%, can well meet the demand of negative ion air purifier, and has a positive significance to promote the development of technology in the field of high voltage DC power supply.