Relationship between electronic ballast and electric light source
Column:Company news Time:2013-05-06
According to different ballast methods used in gas discharge lamps, ballast circuits can be divided into five types: resistance ballast, inductance ballast, capacitor ballast, inductance - capacitor ballast and electronic ballast.

According to different ballast methods used in gas discharge lamps, ballast circuits can be divided into five types: resistance ballast, inductance ballast, capacitor ballast, inductance - capacitor ballast and electronic ballast. In practice, inductance ballast and electronic ballast are applied more. However, the use of inductive ballasts, at 50Hz ac power supply, has a major drawback. First of all, whenever the ac current passes zero, the lamp will produce a fire extinguishing, which will make the lamp tube produce 100Hz flashing, thus reducing the luminous efficiency of the lamp tube. At the same time, the inductive ballast works at 50Hz power frequency, which is bulky and bulky, and consumes a large amount of metal materials such as silicon steel and copper. It is difficult to dissipate heat, has low working efficiency, and has luminescence and stroboscopic phenomenon. However, the high-frequency ac electronic ballast can overcome the above shortcomings of the inductive ballast, which is an effective ballast method.

In 1978, the electronic ballast of high frequency power conversion technology was first used in general lighting fluorescent lamps. With the progress of semiconductor technology and power electronics technology, the application of electronic ballast has been very common today. High frequency ac electronic ballast technology has high luminous efficiency, no strobe, energy saving, easy to realize lighting group control, dimming control and lighting computer networking (such as Ethernet) control (such as using DALI, c-bus, CAN BUS, WLAN and Ethernet LAN technology and other related products), and has been well applied.

At the present stage of electric lighting source, using gas discharge lamp (low pressure gas discharge lamp - fluorescent lamp; It has become a trend that high voltage discharge lamp (mercury arc lamp, high pressure sodium lamp, metal halide lamp, etc.) replaces the incandescent lamp with high power consumption and low efficiency, and it is imperative that high power factor electronic ballast replaces the inductance ballast with high power consumption and low power factor.

Technical requirements for electronic ballasts

When the gas discharge lamp and the electronic ballast are working together, in order to ensure that the gas discharge lamp can be ignited normally and the performance of the lamp is not damaged, the electronic ballast must meet the following requirements:

(1) to both ends of the lamp to provide a high enough start voltage, use lamp reliable ignition. At present, most electronic ballasts generate series resonance through LC series resonance circuit, thus generating the high voltage required for lamp ignition, which is applied to both ends of the lamp to start the lamp ignition. At the same time, the lamp cathode preheating, and preheating time should not be less than 0.4s, cathode preheating voltage or current must meet the relevant requirements of the product standard.

(2) after the lamp ignition, the lamp must provide a suitable size and stable working current. If the working current of lamp is higher than its rated working current, it will affect the service life of lamp. However, if the working current of the lamp is too small, it will affect the luminous efficiency of the lamp. The output power of the electronic ballast, the voltage applied to both ends of the lamp and the actual working current provided to the lamp must match the parameters of the matched lamp.