Design Of HPS Lamps Lighting Regulator Based On AC-Chopper

As a chief one of the third generation green light sources, the HPS lamps are playing a more and more important role in public lighting, which have many advantages such as high luminous efficiency, long operating life and centralized lighting effect. However, the classical HPS lamps which use electromagnetic ballast can not modify the lamp power. These devices have become unsuitable as a part of green illuminating system, which demand the elements should have the capabilities of energy conservation, intelligence and the capability of using in network. As a solution, a lighting regulator using an AC-chopper has been described.A lighting regulating method which uses an AC-chopper is presented. The characteristics of HPS lamps which use electromagnetic ballasts are analyzed. The domestic and international existing states of lighting regulated methods and AC voltage adjusting methods are compared. All these things above prove that the AC-chopper, which has the advantages such as infinitive voltage regulation, without producing low order harmonic components and without influencing power factor, is propitious to be used as an HPS lamp lighting regulator.The paper analyses the operating principle of AC-chopper and describes the working characteristics of AC-Chopper which is approved having dominances as an HPS lamp lighting regulator. Under this foundation, the formula of the main devices'parameters and design of the filter which are used in the situation with specified capabilities and performance criterions. Moreover, the design has been validated by simulation experiment.Considering the working condition of the HPS lamps, a lighting regulator system has been presented, which is made up of a MCU and other automatic modules. The regulator hardwire design has been completed in this chapter, including logic circuit, drive circuit of IGBT, over-zero detect signal and closed-loop control detect circuit, time-control module and power system. The important parameters design method and test solutions have also been given.Furthermore, the lighting regulator software strategies have been designed, such as step-down and holding voltage, lighting scene control, accident detecting and building up network.According to design method, an experiment of 250W HPS lamp has been actualized. The results of test have been given. The control accuracy using in the systems which have different load capacities, the voltage setting accuracy and working effect of the filters are verified. The ratio of fractional energy saving is calculated, when the lighting regulator works according to the time control strategy.