Research on Electronic Ballast for 250W High Pressure Sodium Lamp

In order to meet the need of modern Green Lighting, this article presents a electronic ballast for 250W high pressure sodium lamp to take place of the inductance ballast. The electronic ballast has higher efficient, higher power factor correction and lower total harmonic distortion. A three-stage structure circuit is proposed, including active power factor correction, constant power controlling and low frequency square wave driving circuit. This paper presents the circuit and establishes a ballast sample, 160V~265V wide voltage range input is achieved, power factor is increased to 0.99, total harmonic distortion is reduced to 9.1%. Moreover, the circuit is stable and has good electromagnetic compatibility which has passed the standard test condition.