Synchronous motor are more expensive but have their advantages, otherwise shy should we buy it?
Let's see your questions
1: Harmonics problem depends ok the kind of motor and it's control
2: Starting current: if you use a VFD soft start or a pony motor for start up you should have no starting...
DC motors' speed can be reduced by reducing the DC voltage. In this case you will have the same torque but you will reduce the power.
DC motors can also be controlled by changing the field current and the speed-torque-power carachteristic depends on motor design. You can reduce spedd by rising...
Ok, now I understand the problem.
I'm sorry but I've never worked with this kind of configuration, but alwasy with two converters on two motors mechanically connected so there was no electrical connection between the two converters and ther was no need for triggering.
Sorry but I cannot be...
The two converters don't need to be triggered at the same time.
I'm trying to understand your application. Most probably you are talkin' about two converters controlling two dc motors mecanically connected toegether.
One of the two converter will act as a master determining the torque sharing...
You are right
We normally use alluminium for this king of V blocks
But I also think that the blocks are in the external side of the pole coils, so the losses should be very little because the main magnectic flux path is through the stator core
If i am remembering well... you should calculate the magnetic energy of the system for each position of the mobile magnet.
The force is then the derivative:
F = dE/dx (or -dE/dx)
Where E is the magnactic energy function of the displacement x
I agree both with davidbeach and jraef.
The problem can be one of hte two mentioned
I can be the saturation of the CTs or also the not so good precision of them which cause a false ground current alarm.
Bu als can be the magnetizing current flowing in the motor at the moment you are closing the...
We need more info expecially abou your circuit
Is the motor connected directly yo the breaker or there is a transformer after the main breaker?
Is the main breaker delay correctly setted? Moto can have a starting current of 6 or more times the rated current
Try to be more detailed
Have you ever heard about the "Ward - Leonard" configuration?
Just do a google search...
We use daily this system when testing our motors. It is convenient because we can easily adjust the frequenct, start the motor at slow speed and it is also possible to change voltage settings acting on...
I saw many times that high vibration problem on washing machine was due to a bad installation.
For example, most machines need the drum dampener to be unlocked after installation and a lot of people do not read the instructions and just do not unlock it
It may seem silly but it's real
Greets
Piter
It depends from the electromechanical design.
Motor designer should calculate the torque-speed characteristics based on the pump torque-speed curve in order to have a motor capable of doing it
You can calculate the motor speed after the 0.2 seconds failure, and so you also know motor torque...
I think you should always have only 1 grounding point on a shaft train. Otherwise, whit 2 ore more points you will have groud currents flowing trough the shaft and grounding brushes
2 poles rotor are more expensive than a 4 pole, expecialli in mid-power application (from 200 to 4000kW).
Vibrations on this kind of 2 poles is a big problem, either for the balancing stability (i.e. termal bow) either for the twice line frequence component)
hi all
I spent a lot of time reading your articles
I work in a medium power electric motor and generator factory as a test dep't engineer.
I am specialized in vibration/alignment and balancing.
Some months ago I started writing a balancing software for all the tasks i normalli do during the...
