PRODUCTS

Common Bus Supply Comparison

1. Diode Bridge——non regenerative  common DC bus system


With diode bridge as supply front end, this is the lowest cost front end solution. But poor power factor & harmonic's.



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2. DC791P——non regenerative  common DC bus system


While a 2Q drive as supply front end, this is the middle cost front end solution, this system can provide the supply voltage & pre-charge. But does not provide good power factor and creates harmonic distortion.


 


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3. DC790P——regenerative  common DC bus system


3-Phase 4Q DC Drive, simple & reliable and medium cost & provides line regeneration but requires a step-up transformer, but poor power factor and harmonics. 


 


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4. Active Front End(AFE)——regenerative  common DC bus system


ACTIVE FRONT END (AFE) AC800, reliable and provides 1.0 power factor and zero harmonic's. Provides line regeneration. Higer cost but will pay back to end customer on power cost savings. 

 



AC Drives have two major issues:


1.  Difficulty handling Regenerative Loads

2.  Creation of Harmonics back to AC Power Line


ETD AFE Drives solve both problems!



AC Drives and Regeneration 



How AC Drives Cause Harmonic Distortion



Harmonic Control Methods (single drive)




Regen AC Drives - for Clean Power

  • Input current comparison



  • Harmonic order comparison





The “True Unity Power Factor” Drive


The ETD 4Q AC Drive ensures that input current is always in phase with voltage, regardless of motor speed and load.


UNITY P.F. = 



  • No PF correction needed!


  • No PF utility penalties!



INPUT CURRENT COMPARISON



Applications for Regenerative AC Drives


• Ski Lifts and Cable Cars
• Decanter Centrifuges - wastewater
• Batch Centrifuges

    - Sugar
    - Chemical
    - Pharmaceutical

• Test Stands

    - Chassis Dynamometers

• Stamping Presses
• Windmills & Windfarms
• Pumping
• Paper Mills
• Hoists & Cranes