Study of Design and Development of High Voltage Capacitor Charging Power Supply for Pulse TEA CO2 Laser

In this paper a power supply has been developed for capacitor-charging applications using a series resonant circuit topology, a constant on-time/variable frequency control scheme, and zero current switching techniques. The CCPS is based on a series resonant topology and uses IGTBs as switching devices. The proposed CCPS operates over a wide range of load conditions (varying from nearly short-circuit when the capacitor has no charge to nearly open-circuit when the capacitor is almost fully charged). This kind of performance can be best achieved by supplying a constant charging current: the instantaneous output power then is minimal at the charge beginning and maximum at the charge end. A high voltage capacitor charging power supply (CCPS) developed will be used to charge the primary capacitor bank (4.5µF) up to 3 - 5kV which will be further used to charge the main capacitor bank (38nF) up to 50kV (maximum). The capacitor bank will be discharged through a gaseous medium using high voltage thyratron and will be used to operate a pulsed Transversely Excited Atmosphere Carbon-dioxide (TEA CO2) laser at 200 Hz repetition rate. The main circuit structure of CCPS and a theoretical method for designing of various components of CCPS along with table top model testing has been analyzed in this paper. The results indicate that this design is feasible for use in capacitor-charging applications.