Dynamic modelling of discharge lamps through step response

A simple method to obtain the dynamic behaviour of discharge lamps is proposed. A DC voltage source with a series resistor is used to supply the lamp at the required power level. The lamp response against an input voltage step transient is then analysed. From this analysis, the parameters of the equivalent lamp model can easily be obtained. The proposed method allows the lamp model to be obtained in a rapid manner from a single test, avoiding other time-consuming methods, e.g. lamp characterisation in the frequency domain. Experimental results for a 35 W metal halide lamp are presented.