
speed control for laminate trimmer induction motor
#1
Guest_ed_*
Posted 31 July 2002 - 06:50 PM
#2
Posted 31 July 2002 - 07:28 PM
Welcome to the forum.
Your post suggests that you have an induction motor operating at 30,000RPM. This sounds a little fast!! If it is an induction motor directly connected to the supply, then I would expect that the speed is 3000 (2 pole motor).
Reducing the voltage applied to the motor will eventually cause it to slow down, but unless it is a high slip motor, it would cause the motor to fail. An induction motor is a pseudosynchronous device, that is it wants to operate at the frequency of the supply. Reducing the voltage will reduce the torque and eventually it will stall and operate at the speed where the torque developed by the motor equals the torque required by the load.
If you used a high slip motor and reduced the voltage, the actual speed would vary both with load and voltage. Half voltage and no load would result in full speed operation.
I expect that you will want to have good control over the speed, and in this case you would need to control the frequency aplied to the motor. Unfortunately, to control the speed of an induction motor, you need to use a poly phase induction motor (i.e. a three phase motor) and an inverter. It is not very practical to control the speed of a single phase motor due to the start requirements.
Another option is to use a DC motor and controller, but I would expect that the three phase option would be cheaper.
Best regards,
Mark Empson | administrator
Skype Contact = markempson | phone +64 274 363 067
LMPForum | Power Factor | L M Photonics Ltd | Empson family | Advanced Motor Control Ltd | Pressure Transducers | Smart Relay | GSM Control | Mark Empson Website | AuCom | Soft Starters
#3
Posted 31 July 2002 - 11:22 PM
If not, the motor may be a permanent magnet servo motor. Again, if this is the case there will be an amplifier connected to the motor.
#4
Posted 31 July 2002 - 11:32 PM
Good points. In those scenarios, the speed cannot be changed by simply altering the voltage. I guess we need more information to comment further!
;p;
Mark Empson | administrator
Skype Contact = markempson | phone +64 274 363 067
LMPForum | Power Factor | L M Photonics Ltd | Empson family | Advanced Motor Control Ltd | Pressure Transducers | Smart Relay | GSM Control | Mark Empson Website | AuCom | Soft Starters
#5
Posted 08 August 2002 - 05:40 AM
It looks like it's a simple series machine, so it can operate at high speeds. Operating series machines at lower voltages is possible but speed will depend largely on the load on the shaft.

#6
Posted 01 October 2002 - 03:01 PM
what is a series machine?
#7
Posted 01 October 2002 - 09:54 PM
Welcome to the forum
A series machine generally refers to a DC machine where the armature and field windings are connected in series. The other DC machine configuration is the shunt machine where the armature and field windings are connected in parallel.
Universal machines are brush motors that will run on A.C. but are not synchronous. These can also be series machines.
Best regards, ;d;
Mark Empson | administrator
Skype Contact = markempson | phone +64 274 363 067
LMPForum | Power Factor | L M Photonics Ltd | Empson family | Advanced Motor Control Ltd | Pressure Transducers | Smart Relay | GSM Control | Mark Empson Website | AuCom | Soft Starters
#8
Posted 03 October 2002 - 12:23 AM
#9
Guest__*
Posted 15 March 2005 - 12:29 PM
0 user(s) are reading this topic
0 members, 0 guests, 0 anonymous users