The Analysis of a Thyristor Inverse Parallel Type of Step-up Voltage Circuit for the Discharge Lamp Operation

In the previous paper, the authors treated “Discharge Lamp Operation by Means of a Step-up Voltage Circuit by Back to Back Thyristor Pair.” The advantages of the new lamp operating system are based on the performance characteristics of this step-up voltage circuit, which depends delicately on the constants of the circuit and the phase control angle of thyristors. The obscurity of this dependability is an obstacle to the design calculation, together with the nonlinearity of the discharge lamp's own resistance. Thus, in this paper, with a view to investigate the step-up circuit, the analysis of the discharge lamp operating circuit has been carried out, assumed that both discharge lamp and L-ballast are replaced by a lumped, linearized equivalent load, that is, R-L load. The calculated results have revealed quantitatively the whole mechanism of the lamp operating circuit and provided the characteristics about output, power factor and efficiency that are the foundamental informations to design, and then given the prospects of the practical circuit design method.