Research On Dimming HPS Electronic Ballast Based On Multi Communication Mode

The quality and level of lighting is a significant symbol to evaluate the degree of modernization. As green lighting engineering has been put into practice, High Pressure Sodium (HPS) lamps have attracted considerable attention because of their high luminous efficiency, long lifetime and good color render. However, electromagnetic ballasts for HPS lamp have drawbacks of low power factor, large size, poor power regulation, and analog electronic ballasts still suffer from complex structure, high cost and poor reliability. Moreover, neither of them can monitor or control each HPS lamp remotely, so can not meet the demand of modern lighting development. This dissertation mainly investigates digital, dimmable HPS lamp electronic ballast and its intelligent network management.Further theoretical analysis and experimental results are also presented. A configuration of digital electronic ballast based on microprocessor is proposed. By programming, it can implement complex functions, so that to simplify the circuit and improve the reliability.According to the electric characteristics of HPS lamp, through the analysis of LCC resonant inverter, this paper presents a multi-frequency-sweep soft-startup method, which satisfies the self adaptive startup of HPS lamp.For its nonlinear characteristic during run-up stage, a new control method for different stages of HPS lamp is proposed. During the steady state, an indirect method of average power control of the inverter is used, which simplify the design of system.Aiming at the effective use of sources, a variable frequency dimming method is realized based on the research of dimming methods of electronic ballast. Dimming experiment results of 250W HPS lamp are presented in this part. Network management of lighting system is a development trend in the future. With the help of modern communication techniques, two types of electronic ballast system with different communication modes are established, through which the control center can monitor and control the lamp remotely.