Discussion on the Influence of Driving Electric Power Frequency of Electric Light Source on Light Source Quality

Qingdao ASIC design studio Huabeier microelectronics high-frequency source business unit

Abstract: This paper briefly analyzes the influence of different driving modes of electric light source and different driving electric power frequencies on the technical quality and lighting quality of electric light source and the technical mechanism. The technical countermeasures for improving the technical quality and lighting quality of electric light source are put forward.

Keywords: electric light source inductive ballast electronic ballast drive power source drive electric power frequency stroboscopic effect light effect light source life

Gas discharge electric light source, the frequency of driving electric power is the decisive factor of the technical quality and lighting quality of electric light source. Therefore, understanding and mastering the relationship between the electric power frequency of the electric light source and the technical quality and illumination quality of the electric light source has practical guiding significance for the scientific production and correct selection of the electric light source.

I. Classification of electric light sources : Electric light sources are divided into two categories: thermal radiation and gas emission. In the 21st century, a new type of electric light source for semiconductor solid-state lighting, represented by LED light-emitting tubes, has been developed. The heat radiation illuminating electric light source comprises an incandescent lamp and a iodine tungsten lamp. The gas discharge illuminating electric light source comprises: a straight tube type fluorescent lamp, a mercury lamp, a sodium lamp, a metal halide lamp, an energy saving lamp, and a high-power energy-saving lamp for industrial and commercial use which has been successfully developed in recent years.

2. Driving mode of gas discharge electric light source : The gas discharge illuminating electric light source is mainly composed of a ballast (drive power source) and a discharge illuminant. The discharge illuminator is driven by a ballast, and the ballast is a driving power source of the gas discharge electric source. The driving electric power frequency and driving mode of the driving power source are determined by the type of the ballast and its technical performance.
At present, ballasts (driving power sources) that drive the light source of the electric light source are divided into two types: inductive and electronic. Under the premise that the electric light source is selected, different ballasts are used as the driving power source, and the technical quality and lighting quality of the electric light source are completely different.

three. The influence and mechanism of inductive ballasts (ie inductively driven power sources):
The inductive ballast has no AC current-AC (AC-DC-AC) frequency conversion function, and directly applies 50Hz power frequency AC power to the discharge illuminator to drive the electric light source to emit light. Therefore, inductively driven electric light sources have two inherent technical disadvantages:
- Yes, the electric power applied to the discharge illuminator fluctuates sinusoidally at a frequency of 50 Hz × 2 = 100 Hz. The illuminant produces the emitted light, which also fluctuates sinusoidally at a frequency of 50 Hz × 2 = 100 Hz. The fluctuation depth of the luminous flux is as high as 65%, which produces a serious stroboscopic effect, and its harmfulness is considered to be the danger of the stroboscopic effect of the electric light source and the improvement countermeasures.
Second, the electric power applied to the discharge illuminant is 50 Hz power frequency alternating current, the driving electric power frequency is low, the energy obtained by the gas electrons in the discharge illuminating body is small, the electronic transition energy level is low, and the impact speed is low. The number of ions ionized by the gas is small, the concentration of the electron ions is low, the luminous efficiency of the electric light source is low, and the power consumption is large.
Therefore, in order to eliminate the stroboscopic effect and improve the luminous efficiency, since the 1980s, people in the lighting industry are working hard to develop high-frequency electric light sources driven by high-frequency electric power.

four. The influence and mechanism of electronic ballasts (ie electronically driven power sources):
The realization of the high-frequency electric light source is to use an electronic ballast. Electronic ballast with AC-DC-AC (AC-DC-AC) frequency conversion function. It is not directly applied to the discharge illuminant by the power frequency alternating current, and the electric light source is driven to emit light. Instead, the 50Hz power frequency alternating current is first turned into a stable direct current, and then the frequency converter is turned into a high frequency alternating current (40Khz or more), and then applied to the discharge light body to drive the electric light source to emit light.
The electronic ballast changes the frequency, that is, the frequency of the driving electric power. The impact on the technical quality and lighting quality of electric light sources is mainly reflected in the following three aspects.
One is to eliminate the harmful effects of stroboscopic effects. The stroboscopic effect of the electric light source is formed because the frequency of the driving electric power applied to the discharge illuminator is too low and the luminous flux fluctuates. Further, stroboscopic hazards are formed. If the fluctuation depth of the luminous flux can be reduced to less than 5%, the stroboscopic effect and the hazard can be eliminated. At this stage, its technical measures are: to increase the frequency of driving electric power applied to the discharge light emitter of the electric light source. That is, the AC-DC-AC conversion frequency of the electronic ballast is increased.
Specifically, the three-color high-frequency high-power industrial special energy-saving lamp, the discharge illuminator is a three-primary fluorescent tube. After scientific calculation and experimental verification, the conversion frequency of the electronic ballast should be above 40KHz (thousands of weeks) to ensure that the luminous flux of the fluorescent tube fluctuates below 5%. At the same time, the CE certification of the European Lighting Association also stipulates that the frequency of the electronic ballast should be above 40KHz.
According to the principle of the electronic ballast, the AC-DC-AC conversion frequency of the ballast is increased. It will greatly increase the technical difficulty. It is difficult for companies without professional development capabilities to increase the conversion frequency to over 40KHz.
At present, some energy-saving lamp manufacturers that do not have the ability to develop professional technologies have adopted the method of copying PCB boards (ie, copying technology) to produce high-power energy-saving lamps. The electronic ballast has a switching frequency below 20 kHz (thousands of weeks), and some even below 15 kHz (thousands of weeks). The luminous flux fluctuation of energy-saving lamps is still between 25-40%, and the stroboscopic effect is still serious. This should be paid special attention when purchasing energy-saving lamps.
The second is to improve the light efficiency of the electric light source. The gas discharge illuminating electric light source, the illuminating body of the discharge illuminator, igniting and illuminating, is essentially gas electron ionization. The frequency of the electronic ballast changing frequency, that is, the frequency of the driving electric power, has a great influence on the electron ionization of the electric light source. The driving electric power frequency is high, and the gas electrons in the discharge illuminating body obtain more energy and the electronic transition level is high. The gas electron impact velocity is high, the energy is large, the gas electron ionization speed is fast, the electron ion concentration in the luminescence body is high, and the discharge illuminant has high luminous efficiency.
Specifically, the three-color high-frequency high-power industrial special energy-saving lamp, the discharge illuminator is a three-primary fluorescent tube. Through scientific calculation and experimental verification, the electronic ballast conversion frequency is in the range of 40KHz - 100KHz (thousands of weeks), and the luminous efficiency of the three primary color fluorescent tubes is approximately proportional to the frequency. That is, the higher the frequency of the electronic ballast conversion, the higher the luminous efficiency of the fluorescent tube.
At present, high-frequency and high-power industrial-specific energy-saving lamp manufacturers with scientific research and development capabilities are striving to improve the AC-DC-AC conversion frequency of electronic ballasts to improve the luminous efficiency of electric light sources. Eliminate the harmful effects of the stroboscopic effect of the electric light source. To achieve high quality, high energy efficiency, high brightness, no stroboscopic, long life and excellent quality objectives, improve product competitiveness and brand competitiveness.
The author of this article used energy-saving lamps purchased from the market (the conversion frequency test was around 17KHz), and compared with the high-frequency and high-power industrial special energy-saving lamps produced by our department (the conversion frequency is around 50KHz). Under the same input electric power conditions, the luminous efficiency difference is large.
By returning to the user and field test of our high-frequency and high-power industrial special energy-saving lamps, we use the high-frequency and high-power industrial special energy-saving lamps produced by our department to replace the high-pressure mercury lamps. Replace the 250W mercury lamp illumination with a high-frequency energy-saving lamp with an actual input power of 60W. The on-site illumination is brighter than the 250W mercury lamp, and the color rendering is improved by 4 times, without the stroboscopic effect. The power substitution ratio is 1:5 or above (taking into account that the high-voltage mercury lamp inductance ballast consumes 20% of the lamp power), saving more than 80%, and the investment recovery period is within two months.
When replacing the straight tube fluorescent lamp with the high frequency and high power industrial special energy saving lamp produced by our department, the high frequency energy saving lamp with the actual input power rate of 3OW is used instead of the straight tube fluorescent lamp of the group 4OW * 2=8OW. The field illumination ratio - group 4OW * 2 = 8O W straight tube fluorescent light is also bright, the color rendering is improved by 2 times, no stroboscopic effect harmful. The power substitution ratio is 1:3 or above (considering the power consumption of the straight tube fluorescent ballast ballast accounts for 20% of the lamp power), saving more than 70%, and the investment recovery period is within three months.
The third is to improve the life of the electric light source. The gas discharge illuminating electric light source, the illuminating body of the discharge illuminator, igniting and illuminating, is essentially gas electron ionization. The frequency of the electronic ballast changing frequency, that is, the frequency of the driving electric power, has a great influence on the electron ionization of the electric light source. The driving electric power frequency is high, and the gas electrons in the discharge illuminating body obtain more energy and the electronic transition level is high. The gas electron impact velocity is high, the energy is large, the gas electron ionization speed is fast, and the electron ion concentration in the luminescence body is high.
The higher the driving electric power frequency, the faster the gas electron ionization speed, and the higher the energy level obtained by the ions. At the time of Qihui, the discharge illuminator ignites quickly, and the filament cathode is sputtered small. Each time the lamp is turned on, it can be ignited once (on and off). After ignition of Qihui, the concentration of electron ions in the illuminator is high, the loss of the discharge illuminator is reduced, the temperature of the discharge illuminator is low, and the light of the discharge illuminator is slow. The technical performance of the ignition illuminating and discharge illuminating of the discharge illuminant is improved, so that the igniting life of the discharge illuminant is higher than the original design life, and the effective ignition time of the discharge illuminant is greatly prolonged.
The author of this article used a straight tube fluorescent tube with both ends blackened and filament burned out (the inductor ballast could not be illuminated), and the high frequency (5OKHz) electronic ballast experiment produced by our department was used. If you succeed, you can ignite the light normally.

Fives. in conclusion:
For gas discharge electric light sources, different drive power sources and different drive electrical power frequencies. It has a decisive influence on the technical quality and lighting quality of electric light sources. The driving electric power frequency is high, the electric light source technology is excellent in quality, the lighting quality is high, the driving electric power frequency is low, the electric light source technical quality is inferior, and the lighting quality is poor.
At this stage, comprehensive consideration is given to factors such as the performance price ratio of electric light sources, lighting quality standards, and lighting operating costs. Widely promote the application of high-frequency all-electronic ballasts and high-frequency and high-power industrial-specific energy-saving lamps, which can build an efficient, energy-saving, bright and comfortable green lighting environment in the whole society.

Han Yurong 0532 8760830 1360 630 6833