The dimming system efficiency and heat dissipation problem
Light, is the life of the TV art. The dimming system safe and reliable, it is used to shape a powerful guarantee for the objective world. Any a professional with a dimming system, its power is very big, is a single light bulb is 5 kw or even 10 kw, thousands of bulbs and a performance available. A dimming system, therefore, the total power consumption is amazing. So, the dimming system efficiency and heat dissipation is very important, it is dimming system for a long time operation and the key to keeping its reliability.
Dimming equipment has experienced four generations: the first generation of resistance type dimmer. The second to transformer type dimming device. The third generation is electromagnetic amplification shape the dimming equipment. The fourth generation is thyristor dimmer equipment. The efficiency of the minimum of the first generation, the fourth generation of highest efficiency.
If the dimming system efficiency is not high, its the consumed power is considerable. Assuming that its efficiency is 96% (seems to have been a good number), when it wants to push a 6 kW load, its power consumption is: 6 x (100% 96%) = 0.24 kW
And suppose that a move light clothes closet 60 6 kW load, at this time, it is as high as the total power consumption: 0.24 x 60 = 14.4 kW
So, it is important to improve the efficiency of the adjustable optical-intensity system. It not only reduces the rise of temperature of the clothes closet that move light (because the temperature rise and power consumption is proportional to the), but also reduce the power consumption, thereby lowering operating costs. At present, the more advanced the dimming system adopted the latest solid switch and efficient.
Its efficiency is as high as 98%, reduced due to the 100% of light made a sharp rise in current interference. (silicon controlled rectifier is by changing the conduction Angle to adjust the voltage, its conduction time is only about 1 mu s or so, the current waveform is actually a frontier is steep pulse.)
However, even if is a very efficient dimming system, the performance of cooling system and the design is very important. Even 98% efficiency, in the above, for example, its power consumption is still as high as 7.2 kW. To put such a big power consumption effectively outside of the system, maintain internal system components at a reasonable temperature environment, reasonable design of the cooling system is not allow to ignore.
At present, the world popular clothes closet on the cooling system has 3 kinds: forced air supply, convulsions and smart convulsions.
(1) the forced air supply
The cooling system is to put the fan installed in the bottom of the cabinet, to make fresh air from the bottom of the cabinet to accelerated after blowing up, to take away the heat generated by the thyristor.
This approach has the advantage of high efficiency, with a small fan can put a lot of tropical. Its drawbacks smoke into the air from the bottom on our way up flow by continual thyristor power heating, so at the top of the silicon controlled temperature is much higher than the bottom, leading to the top of the silicon controlled the reliability and life of the decline.
(2) mandatory convulsions
The design of this system is to put the suction fan installed in the top of the cabinet. Through the proper process design make fresh air into the front of the each SCR, then through convulsions and hot air into the cabinet.
This method through the precision design (fluid dynamics) and rigorous process control, can do it from top to bottom every into the air volume of SCR is roughly same, so you can make each thyristor is in an acceptable range of temperatures, to ensure the reliability of each thyristor. But this kind of design has its drawbacks as well as, is the wind resistance is bigger, need to increase suction fan power, so the noise is bigger also.
(3) intelligent convulsions
Because in the general operating situation, the dimming system rarely is full, in this way, the required air volume can be relatively reduced. Intelligent convulsions is according to this theory, by detecting the temperature inside the cabinet, and then decided to smoke air volume, under the operating environment of general fan's speed, noise is relatively lower, but when the load increases, the fan will speed up accordingly. In this way, both retain the advantages of mandatory convulsions, solved the disadvantage of high noise at the same time.
Finally it is worth mentioning that although had high light efficiency and good cooling system, but the dimming system is always a great electric power system. The phenomenon such as high temperature and the emergence of arc ignition is impossible to completely avoid. Only on the basis of high efficiency and good heat dissipation, along with the necessary heat and fire prevention measures, such as using high temperature flame retardant wire), only can be used to ensure the safety of the adjustable optical-intensity system.