Light, is the life of the TV art. The safety and reliability of the system is to use light to create a strong guarantee for the objective world. Any professional use of the dimming system, its power is great, a single bulb is 5kW or 10kW, while a show can be used on a thousand lights. Thus, the total power consumption of an adjustable optical system is amazing. Therefore, the efficiency and heat dissipation of the system is very important, which is the key to maintain the reliability of the system.
Dimming equipment has experienced four generations: the first generation of resistance type light regulator. The second generation is a transformer type dimming equipment. The third generation is an electromagnetic amplifier type dimming equipment. The fourth generation is a controllable silicon dimming equipment. The efficiency of the first generation is the lowest, and the efficiency of the fourth generation is the highest.
If the efficiency of the optical system is not high, the power consumption of the system is considerable. Assuming its efficiency is 96% (it seems to be a very good number), when it wants to drive a 6kW load, its own power consumption is already:
6 x (100%96%) =0.24kW
And if a dimmer cabinet load, 60 6kW at this time, the total power consumption is as high as it:
60 x 0.24 = 14.4kW
So it is very important to improve the efficiency of the system. It not only reduces the dimmer cabinet temperature (because of temperature rise and power consumption is proportional to), but also reduce the power consumption, so as to reduce the operation cost. At present, the more advanced light adjusting system uses the latest solid switch and high efficiency.
Choke, its high efficiency is more than 98%, greatly reduced due to interference of non dimming to 100% current rises sharply caused. (SCR is adjusted by changing the conduction angle to adjust the voltage, its conduction time is about 1 s or so, the current waveform is actually a very steep edge of the pulse.
However, even a very efficient dimming system, the performance and design of the cooling system is still very important. Even if the efficiency of 98%, in the case of the above, its own power consumption is still as high as 7.2kW. To put such a large power consumption effectively outside the system to maintain the system of internal components in a reasonable temperature environment, the reasonable design of the cooling system can not be ignored.
At present, the world of popular cabinet cooling system has 3 kinds: forced draught, forced draught and intelligent ventilation.
(1) forced air supply
The cooling system is the blower installed in the bottom of the cabinet, so that fresh air blowing from the bottom of the cabinet after entering the accelerated to, and carry away the heat produced by the controllable silicon.
The advantage of this approach is of high efficiency, with a small fan can put a lot of tropical go. Its disadvantage is that the cold air pumped into the air from the bottom to the top of the flow of the power of the continuous flow of power heating, so the top of the silicon temperature is much higher than the bottom, resulting in the top of the reliability and life of the controllable silicon.
(2) forced draft
The design of this system is that the exhaust fan is installed on the top of the cabinet. Through the appropriate technology design, the fresh air from the front of a controllable silicon into and then through an exhaust the hot air row to the outside of the cabinet.
This method can be controlled by precise design (fluid dynamics) and rigorous process, which can be achieved from the top to the bottom of each controllable silicon into the air flow is approximately the same, so that each SCR can be operated in an acceptable temperature range, ensuring the reliability of each controllable silicon. However, this design also has shortcomings, is the need to drag larger, increasing the power of the exhaust fan, so the noise is larger.
(3) intelligent ventilation
Because under normal operating conditions, dimming system will rarely be full, so, the amount of ventilation required can be reduced. Intelligent ventilation is according to this theory, by detecting the temperature in the cabinet rise, then decided to ventilation, in general operating environment wind machine only needs the low speed operation, noise is relatively lower, but when the load increases, fan will correspondingly acceleration. So, not only retains the advantages of forced ventilation, also solves the disadvantages of high noise.
Finally, it is worth mentioning that, although there is a high dimming efficiency and good cooling system, but the dimming system is always a great power system. The high temperature and the arc ignition phenomenon can not be completely avoided. Only on the basis of high efficiency and good heat dissipation, coupled with the need for high temperature and fire prevention measures (such as the use of high temperature flame retardant wire), it can ensure the safety of the whole dimming system.