The purpose of this study is to design a touchable and regulated high-voltage power supply with high power factor to address the problem of dielectric barrier discharge (DBD) power supplies, which are prone to load mismatch due to internal confinement.
A power factor correction DC regulator circuit is designed based on the L6562 chip, an insulated gate bipolar transistor (IGBT) driver circuit based on STM32 chip to generate two pulse width modulation signals. The signals are isolated by 6N137 chip and amplied by totem pole circuit to drive the IGBT. The over-current and over-temperature protection circuit consist of comparator circuit and RC delay response circuit. The power supply uses the STM32 to sample the current andv temperature feedback voltage, then judge whether to turn off the signals according to the size of voltage.
Over a wide voltage input range from 85 to 265 V, the measured factor of the power supply is up to 0.96. The frequency changes from 5.5 to 25 kHz. The duty cycle changes from 0% to 40%. And the shutdown response time changes from 5µs to 10µs. When the output power is up to 250 W, the power efficiency is 90%.
Compared with the traditional one with low power factor, cumbersome operation and complex control, a touchable and regulated power supply is developed with high power factor and reliable protection circuit. The parameters of frequency and duty cycle are adjustable on a touch screen. The operations are more convenient, accurate and intuitive which enables the power to quickly match different DBD loads.
