Analysis of pulsed discharge characteristics of solid-state switch (IGBT) based 16 kHz repetition rate, 100 W average power copper-HBr lasers

作者：Biswal R^*; Agrawal P K; Mishra G K; Dixit S K; Nakhe S V

来源：Journal of Russian Laser Research, 2012, 33(4): 319-335.

DOI：10.1007/s10946-012-9296-5

• copper-HBr laser
• IGBT switch
• pulsed gas discharge
• electrical power deposition

We present for the first time a comprehensive analysis (both time resolved and time averaged) of the gas-discharge characteristics of a solid-state switch (IGBT) based on high average power (100 W class), high pulse repetition rate (16 kHz) copper-HBr laser under various excitation conditions. We evaluate various discharge-plasma parameters such as the electrical inductance, electrical resistance, active laser-head voltage, active electrical power, pre-pulse electron density, and axial gas temperature by numerical processing of the measured laser head voltage-current waveforms. For the first time, we evaluate fractional losses at various intermediate stages of the circuit elements as well as effective coupling for the laser excitation process during transfer of energy from the wall plug to the laser-discharge plasma. We conclude that irrespective of the capacitive storage input power (P (in)), a constant fraction of similar to 40% of P (in) is coupled into the laser-discharge plasma. With a low to moderate specific input power of 0.4-0.7 kW/a"", the tube produced 70-110 W average output power at an efficiency of a parts per thousand 3.2-2.8%, respectively. The average laser performances at various P (in) are correlated to its time-resolved and average gas-discharge parameters such as the inter-pulse electron density and axial gas temperature.

• 出版日期2012-7