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Mahmood Elnasser
01/03/13 09:53
  01/03/13 10:06

Read: 661 times

Msg Score: +1
 +1 Good Answer/Helpful
#189063 - Soft starting
Responding to: Raghunathan's previous message
I dont think I can simply use a power contactor + back up fuse to start ?? Or can I ??

No you can't, you will always blow the fuse up or the power source because dc motor draws 5x the rated current at startup. You must use some sort of soft starting.
Since you don't need speed control why not build a soft starter yourself, all you need is a microcontroller to generate PWM starting from 0 PWM to 100% in 20 seconds say. And use a gate drive and IGBT. Don't forget the DC link capacitor to protect the IGBT from BEMF.
Last week I installed a commercial 350A digital dc drive for a client, it is amazing how much technology in it. The thing I liked most is the autotune feature, it measures the motor parameters like armature resistance, inductance, flux and calculates the PID parameters and stores the values in the drive.

List of 11 messages in thread
Starting a 110V DC / 10KW motor      Raghunathan      01/03/13 05:10      
   RE        Jacob Boyce      01/03/13 06:44      
      Back to basics !      Raghunathan      01/03/13 21:59      
   Soft starting        Mahmood Elnasser      01/03/13 09:53      
      Good ideas..      Raghunathan      01/03/13 22:03      
         more       Mahmood Elnasser      01/04/13 05:20      
            IGBTs and money      Erik Malund      01/04/13 07:42      
               A very practical tip. Thanks.      Raghunathan      01/04/13 09:16      
               110VDC      Mahmood Elnasser      01/04/13 11:20      
            All on the module !      Raghunathan      01/04/13 09:16      
               COMPLETE saturation      Erik Malund      01/04/13 13:27      

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