Research On Electronic Ballast For 400W High Pressure Sodium Lamp

High Pressure Sodium Lamps (HPS) are notable for their high luminous efficacy, good color rendering and long life. But the traditional ferromagnetic ballast for HPS lamps due to lower power factor, high igniting current, lower efficiency, and large size, cannot satisfy the requirements for green energy. So it is time to design the electronic ballast to replace the core-coil ballast. A new method of planning electronic ballast is put forward to La this paper. Theoretical analysis and experimental results are given for the proposed electronic ballast.The operation characteristics and the limitations under high condition of HPS lamps are described. According to these , a new low frequency invert circuit is designed based on current-track in this paper.Analyzing the igniting method of LC resonance and considering the control of the inverted main circuit, this paper designs an igniting circuit with transformer coupling controlled by logic. The advantage of the above circuit is that it does not need any separation, moreover the other parts hi the circuit does not damaged by the thousands of volts during the igniting.What more, this paper presents the theory of the power factor correction, and design the appropriated circuit with the chip of PFC-UC3854A/B.