A New CW CO2 Laser with Precise Output and Minimal Fluctuation by Adopting a High-frequency LCC Resonant Converter

Lee, Dong-Gil;Park, Seong-Wook;Yang, Yong-Su;Kim, Hee-Je;Xu, Guo-Cheng

  • Received : 2011.03.13
  • Accepted : 2011.09.18
  • Published : 2011.11.01


The current study proposes the design of a hybrid series-parallel resonant converter (SPRC) and a three-stage Cockcroft-Walton voltage multiplier for precisely adjusting the power generated by a continuous wave (CW) $CO_2$ laser. The design of a hybrid SPRC, called LCC resonant converter, is described, and the fundamental approximation of a high-voltage and high-frequency (HVHF) transformer with a resonant tank is discussed. The results of the current study show that the voltage drop and ripple of a three-stage Cockcroft-Walton voltage multiplier depend on frequency. The power generated by a CW $CO_2$ laser can be precisely adjusted by a variable-frequency controller using a DSP (TMS320F2812) microprocessor. The proposed LCC converter could be used to obtain a maximum laser output power of 23 W. Moreover, it could precisely adjust the laser output power within 4.3 to 23 W at an operating frequency range of 187.5 to 370 kHz. The maximum efficiency of the $CO_2$ laser system is approximately 16.5%, and the minimum ripple of output voltage is about 1.62%.


LCC resonant converter;HVHF;Cockcroft-Walton


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