Experimental Study On The Light Flicker Effect Of LED Caused By The Voltage Containing Inter-harmonics

There is a lot of inter-harmonics in the power grid with the development of various non-linear load, in particular the frequency device. When the inter-harmonics in the power grid exceeds a certain limit. It will lead to voltage fluctuation and flicker phenomenon which will seriously affect the visual comfort and work efficiency. For incandescent and compact fluorescent lamps, there already have some research with the Flicker phenomenon with the inter-harmonics. But at the present, the LED is more and more popular, but little research about it has been done. The research of LED light source flicker effect under the inter-harmonic has important theoretical and practical value for inter-compatible with the standard complement harmonics.In this paper, we will base on the existing IEC flicker meter decomposition model. The decomposition model can import the flux wave from experiments directly to calculate the Pst. The flicker meter decomposition model also can calculate different light sources fluctuations flicker with different types of voltage. Referring the existing experimental methods of fluorescent Flicker under inter-harmonics, design and improvement the experimental environment,build the experimental platform. Use the IEC flicker meter decomposition model to get the experimental study. It obtains the LED light flicker Pst at different frequencies and harmonic content. And according this we draw the LED light source flicker limit curve.The paper also analyze on inter-harmonic restrictions curves, analyze the characteristics of the LED light flux fluctuations under single Inter-harmonics, LED flicker mechanism, the relation between LED flicker limit and voltage fluctuation, the relation between LED flicker intensity and peak voltage fluctuation, etc. It comprehensive explains the proposed of LED light source flicker phenomenon under a single inter-harmonic conditions. However, in real life, the pair of inter-harmonics is more common, in order to make the LED light source flicker study under inter-harmonics conditions more comprehensive practical. At the present experimental conditions, we preliminary study and make the LED light flicker limit curve under the pair of inter-harmonic, then analyze the LED light source flicker characteristics under pairs of inter-harmonics.Finally, the paper combine the results of existing research, contrast the three common lamp(incandescent, fluorescent, LED) light flicker limit curve and flicker characteristic, compared the flicker limit curve and flicker characteristic with different power, different temperature and the different drive LED light. This paper analyzed the similarities and difference. It says warm temperature, low power, and the LED with constant current driver is not prone to flicker.