Which is the best motor type for this application?
Which is the best motor type for this application?
(OP)
Hello,
I need to build a test instrumentation for a customer and I would like to ask your feedback regarding the best motor type to be used.
The system will be made like this:

The goal is to actuate a torque profile in a way that the force acted on the rope by the device is opposed.
The requirements are:
1- The control needs to be with torque set point (I need to create a torque profile)
2- The torque required ON THE MOTOR is from 1Nm to 4 Nm and I can not decrease it adapting the mechanical transmission
3- The motor will actuate this torque very often with 0 speed
4- The power supply will be 230 VAC 1-phase and, if required, I can use a Vac-Vdc converter
5- The cost of the equiment must be as low as possible
If I didn’t have any cost costraints my choice would be AC brushless motor + servo drive and by this solution I could satisfy all the requirements but, unfortunately, it is absolutely too expensive for the customer.
So I am searching for cheaper solution. I searched for DC motors and AC motors but I don’t have a lot of experience with this kind of motors and I ask your help.
Can you please give me your feedback about it?
Please write me if something is not clear and thanks in advance!
Thanks!:)
I need to build a test instrumentation for a customer and I would like to ask your feedback regarding the best motor type to be used.
The system will be made like this:

The goal is to actuate a torque profile in a way that the force acted on the rope by the device is opposed.
The requirements are:
1- The control needs to be with torque set point (I need to create a torque profile)
2- The torque required ON THE MOTOR is from 1Nm to 4 Nm and I can not decrease it adapting the mechanical transmission
3- The motor will actuate this torque very often with 0 speed
4- The power supply will be 230 VAC 1-phase and, if required, I can use a Vac-Vdc converter
5- The cost of the equiment must be as low as possible
If I didn’t have any cost costraints my choice would be AC brushless motor + servo drive and by this solution I could satisfy all the requirements but, unfortunately, it is absolutely too expensive for the customer.
So I am searching for cheaper solution. I searched for DC motors and AC motors but I don’t have a lot of experience with this kind of motors and I ask your help.
Can you please give me your feedback about it?
Please write me if something is not clear and thanks in advance!
Thanks!:)





RE: Which is the best motor type for this application?
Walt
RE: Which is the best motor type for this application?
I searched about winch and hoist but it seems that is not possible to define torque profile (not fixed torque) or to change (by software algorythm) the desired torque while the test is in progress..do you know if it is possible with these devices?
Thanks
RE: Which is the best motor type for this application?
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Which is the best motor type for this application?
RE: Which is the best motor type for this application?
RE: Which is the best motor type for this application?
RE: Which is the best motor type for this application?
RE: Which is the best motor type for this application?
Cheaper ways to control force are weights, levers, springs, pneumatics or hydraulics.
RE: Which is the best motor type for this application?
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Which is the best motor type for this application?
RE: Which is the best motor type for this application?
RE: Which is the best motor type for this application?
"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington
RE: Which is the best motor type for this application?
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Which is the best motor type for this application?
thanks to everyone for the reply.
Customer would like to avoid the usage of pneumatic air and now the possible solutions are:
1- VFD with flux control: I agree with jraef and I think that this solution is feasible but not extremely cheap
2- Servo Motor: from my point of view (except for the price) this would be the best solution and I could really use torque profiles with closed loop (with the torque on the motor shaft).
3- DC Motor: I never used one but probably this solution would be the cheapest.
In all these solutions the problem said by Compositepro remains and the way to decrease it would be to find a way to decrease the gear ratio or to find a smart mechanical transmission.
I have two more questions: speaking about the DC motor torque control. In your experience, the performance of the torque control are similar to the servo ones? And, moreover, considering that the motor will often actuate the torque at zero speed, will it damage the motor on the long run?
Thanks!
RE: Which is the best motor type for this application?
Depends. Most servo motors can run motionless continuously without frying. When you reach certain power levels and sizes that breaks down and they start limiting you to duty cycles.
Keith Cress
kcress - http://www.flaminsystems.com