ENERGY EFFICIENCY CALCULATION OF GAS-DISCHARGE FLASH LAMPS

Subject of Research. The paper presents a technique for simultaneous measurement of the radiation energy spectrum and the electrical parameters of a high-current pulsed arc discharge. The proposed approach provides the calculation of the energy and power parameters of the discharge and the efficiency of electric energy conversion into radiative one in different spectral ranges. Method. The energy efficiency of flash lamps was calculated by two separate methods: the measurement of gas discharge electrical parameters and detection of radiation energy spectrum. The electrical parameters were measured by assembling a circuit using a coaxial non-inductive shunt and three mixed-type voltage dividers combined with their earth terminals at one point for fall-of-potential measurement on the lamp and capacitor. The combining of earth terminals made it possible to register simultaneously the voltage drop at different points without the risk of oscilloscope failure. By the mathematical multiplication and integration, the energy and power characteristics of the circuit and the pulsed gas discharge were obtained. The radiation characteristics measurements were carried out by applying a spectrometer and calibrated photodiode radiation detector. The spectral distribution of the radiation source was obtained and radiation efficiency was specified in the chosen wavelength intervals. By calculating the radiation energy in the spectral range corresponding to the applied task and taking into account the previously obtained values of the dissipated energies in the circuit and discharge, the radiation efficiency is found in the selected wavelength ranges. Main Results. On xenon flash lamp example with 5 mm internal diameter and arc length of 120 mm, oscillograms of the current and voltage drop on the capacitor and lamp were obtained. The calculated radiation efficiency values in the spectral ranges of 200-250, 200-300 and 200-400 nm were 2.7, 9.3, and 28 %, respectively. Practical Relevance. The proposed method gives the possibility to register simultaneously the current and voltage drop on several sections of the discharge circuit and radiation characteristics, and eliminates the necessity to take into account the instability of these parameters from pulse to pulse. The calculation of the radiation efficiency in any wavelength range included in the spectral interval of the spectrometer sensitivity enables the designers of systems with flash lamps to optimize the discharge circuit based on the radiation requirements of specific applications.