A low cost electronic ballast for 250 W high pressure sodium vapour lamps using the CC/CC buck converter as power factor preregulator [CC/CC read DC/DC]

In this paper, a low cost electronic ballast with power factor correction for 250 W high pressure sodium vapour lamps is presented. The electronic ballast is based on a two-stage scheme. The first stage realises the power factor correction by using a CC/CC buck converter operating in discontinuous conduction mode (DCM) and constant duty cycle meeting the standard IEC 1000 3-2 with a very low cost circuit. The second stage is based on a resonant full-bridge LCC series-parallel inverter with resonant current mode control and optimum commutations. This current mode control minimises the losses in the switches and the return of power to the input power supply.