Power Quality Influence And Countermeasures On Building Electrical Lighting System

Building electrical lighting is closely connected with our production activities,daily life and job.Recently,with the significant raise of urbanization level,the vigorous development of construction industry and the continuous improvement of living standard in China,people have made higher demands on quality,comfort,aesthetic property and energy saving of illumination.High quality lightings can provide with comfortable lighting environment,therefore,it will naturally improve people's efficiency of study,work and production.Power quality problems in electrical lighting system directly affect the illuminating quality.To determine a better lighting environment,this paper addresses power quality influence and countermeasures on building electrical lighting system,its main content is:(1)As the basic concepts in this paper,electrical lighting system and power quality serve as the theoretical foundation in the overall research to explore the varying effects of power quality on electrical lighting system.First of all,the photometric system of electrical lighting,the influencing factors of illuminating quality,the types of lamp sources and calculated method of illuminate are introduced.Secondly,fundamental theory bases of electrical lighting system design is presented,including the power supply voltage and network of lighting system,the calculation of the lighting system load and the selection of wire,and especially the meaning of improving power factor.Finally,the causing reason and effect of each indicator of power quality is stated to provide theoretical basis of the influence and improvement of power quality in lighting system in the following study.(2)Each indicator of power quality,namely the voltage deviation,voltage fluctuation and flicker and inter-harmonics,is raised to analyze the influence and improvement of power quality in electrical lighting system based on the basic theory of electrical lighting system.Specifically,the power quality problems on lighting include illumination deviation,reduction in the service life and flicker of lamp sources.This paper starts from the cause of power quality problems as above mentioned,then points out the preventive measures of different problems.The adjustment of transformer taps can be used to weaken the voltage deviation,and reducing voltage loss in power system by lowering impedance and improving power factor can also do it.The independent circuit of power supply,the improvement of the voltage level and dynamic reactive power compensation are adopted to hold up the voltage fluctuation and flicker.As for inter-harmonics,it is controlled by passive filter and active filter devices.And the working principle and styles of reactive power compensation device,passive filter and active power filter have been studied in more detail in follow-up papers.(3)With an example of practical engineering,the design scheme of reducing the influence of power quality in lighting system is studied and analyzed.By optimizing the grid design,using the ways of reactive power compensation device and active filtering device to improve power quality in lighting system.Matlab/Simulink software has been used to analyze the design scheme of improving the power factors by using thyristor switched capacitor(TSC)and active filtering device(APF).The results show that the scheme obtains high feasibility.