Research And Design Of Digital Ballasts For High Pressure Sodium Lamps

In the gross national product of our country,the electric light source plays an important role.As the most representative of the third technological revolution in light source products,high power gas discharge lamp,high-pressure sodium lamp in which plays a huge role in the traffic field.With the development and popularization of lighting,high pressure sodium lamp is increasing in the growth of market,developing high-quality power supply and digital control has already represented the general trend,which is a hot technology in the field of power.This paper aimed at the design of high power high voltage sodium lamp electronic ballast for high pressure sodium lamp,the PHILPS SON series of 600W lighting,mainly used in highway lighting.This paper introduces the digital electronic ballast for high pressure sodium lamp to the application in the design process of academic theory,which is the design of the selected suitable plan.Specific theories include power factor correction(PFC)technology,high frequency inverter technology,ignition technology,acoustic resonance suppression technology and sampling technology,making the gas discharge lamp to achieve constant current control and the ballast with protective function.The most important digital control core device is using DSP 2812 as the main control chip.City power throughs the L6562 chip which is the core device of the active power factor correction circuit and provides the 400V to the bus.400V DC voltage throughs DSP 2812 chip used as the half bridge inverter circuit of PWM controller and puts high frequency AC voltage,supplying AC voltage for high voltage sodium lamp.The integrated circuit scheme based on IR2110 chip as the core drives the half bridge power switch.The series parallel LCC resonant circuit is used to start the ignition mode,and the current and the AD converter are realized by using the current Holzer sensor to realize the constant current control.Frequency modulation control of output PWM solves the problem of acoustic resonance.Finally through the test,the performace of the whole system meets the design objectives,achieving normal and stable operation of the high-pressure sodium lamp,which lays a good foundation for the next research and development production.