The parameters of the resistance model are obtained through various experiments under different lamp power in this study. Polynomial fitting curves are obtained for these parameters to get the values under some certain lamp power. Then simulations in PSIM are conducted by using the calculated values to verify the reliability and accuracy of the method adopted. Good agreement is obtained between the experimental results and simulation results. Finally, In order to improve the lifetime of the lamp and increase the UV irradiance at 253.7nm, the double capacitor topology is proposed and studied.