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professional dimmer question

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talexop

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igbt in dimmer

Dear ALL,
I have some questions to ask you concerning the dimmers. I am thinking of re-designing a dimmer module of ours. In this dimmer we used triacs for Forward phase control. I wish to change the dimmer technology to a newer one like IGBT’s but to tell you the truth we are a little bit concerned about the high temperatures of the IGBT’s.

I know that the triacs dispose around 1W per 1A of heat. What about IGBT’s?
Would you be kind enough to provide us with documents for IGBT’s dimmer schematics?
What about sine-wave dimmers?
Is this kind of dimming achieved with IGBT’s?
Can we find any resources for sine-wave dimmers?
Which is the best method for dimming ?
triacs?
SCRs?
Quadracs?
Can we dim with alternistor triacs?



Well thank you in advance.


Sorry for all the questions ..

Best Regards,
Thanos
 

Davood Amerion

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professional dimmer

I think IGBT (or any type of transistor) not sutible for AC mains voltage.
on the other hand SCR and triac are excellent to work with AC voltage.
 

talexop

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igbt sinewave dimmer

I disagree with you. IGBT's have a lot of advantages over triacs especially to EMI. But the main problem is the heat they produce!!! Because the dimmer case is not very big and I want two dimmer modules in one box the HEAT is very important to me..

Thanks for your answer..
 

btbass

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igbt bridge dimmer

I do not think heat will be a problem, IGBT's can be more efficient than triacs. I work with high voltage motor drives (450volts, 15 Amps) and IGBT's are the device of choice. There are some very good powerful devices available at reasonable cost with high switching speeds. Used as a switch, dissipation is low. Check IR for small metal devices with large heatsink contact area. A reverse phase dimmer can easily be implemented reducing the need for large filter chokes. A better solution is to use PWM control at a frequency of ~20KHz. Comparitivly slow for IGBT devices so low switching losses. A sine wave can be generated by the PWM module if required. One simple topology is to use a bridge rectifier on the AC line with the IGBT across the DC connections. Modern devices also have positive thermal characteristics for simple paralleling. These babies are what control Fork lift Trucks and Welding machines!
 

    talexop

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