SIMOTICS

how torque is controlled in Vector Control mode

Thread Starter: Import-User-1   Started: 4/18/2012 1:14 PM   Replies: 3

  4/18/2012, 1:14 PM

Import-User-1 Joined 8/10/2005 Last visit: 6/19/2013 Posts: 3063 Rating:  (17)

(0)  Mothilal wrote: hi Vithani     I have one fundamental doubt in drives... In vector control , how do you independently control the torque producing current and flux producing current in an INDUCTION MOTOR?    ' If you give the supply voltage  to the motor winding, the motor draws a required current depending on winding impedance. Then how do you control the current independantly? Both active and reactive current are flowing in the same winding ( due to the PWM inverter supply voltage)..  Vector control is only for operating the motor at setpoint torque value? or It operates the motor at specified setpoint speed and specified setpoint torque? (i.e for example 2 Nm at 150 rpm and 2 Nm at 500 Rpm)   In VC drives, How do u adjust the motor input voltage and frquency  to control the reactive and active current independently?   Please clarify my doubt if u have any idea... Thanks Regards

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  4/18/2012, 1:16 PM

Import-User-2 Joined 8/10/2005 Last visit: 6/6/2013 Posts: 1471 Rating:  (21)	(0)  Vithani wrote: Please refer following Link  Electric motors, generators & controls engineering Forum at Eng-Tips I hope this will make you clear
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  4/19/2012, 6:25 AM

Mothilal Joined 11/30/2011 Last visit: 3/12/2013 Posts: 164 Rating:  (21)

(0)  one more answer: This explanation is given by PISCEAN 2010: " in case of sensor less vector control drives during tuning, drive calculates the no load current or magnetization current of motor. Generally this is known as no load current. When motor is loaded, drive measures the actual current drawn by motor. If the drive is configured as torque set point it will try to keep current constant. (As drive know the magnetization current, rest thing is it simply tries to keep other i.e. load current constant) If the measured current starts dropping it just busts & keeps the load current constant. This is how sensor less VC drives works.Hope I am able to clarify your doubts" Regards Mothilal ***ALL IS WELL***

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  4/19/2012, 1:19 PM

Vithani Joined 7/8/2009 Last visit: 6/20/2013 Posts: 1180 Rating:  (327)	(1)  Import-User-2 wrote: Vithani wrote: Please refer following Link  Electric motors, generators & controls engineering Forum at Eng-Tips I hope this will make you clear Corrected Link is http://www.eng-tips.com/faqs.cfm?fid=1062 Please have a look on that Its very nice explanation on VC Regards Devesh Vithani I dont Like people driving Fast, thats the reason I overtake them ;)
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