Post History
Is it possible to drive a PMSM motor - here I am referring to an AC motor with permanent magnets(stator wounded, rotor with PM) - in a way that there is no externally mounted rotor position sensor(...
#3: Post edited
by
2kind
·
2021-09-22T20:14:44Z (about 3 years ago)
Is it possible to drive a PMSM motor - here I am referring to an AC motor with permanent magnets(stator wounded, rotor with PM) - in a way that there is no externally mounted rotor position sensor(no hall, encoder, or resolver) using the variable frequency method as one would typically drive an AC induction machine(stator wounded, rotor squirrel-cage)?- The load that the PMSM motor would drive is a fan(yes, I know the torque-rpm curve of it is nonlinear rather than linear) so there is no stall-torque issue.
- If the presented scenario is possible, then the questions are:
- - Is the efficiency lower in this scenario in comparison with the one when there is a rotor position sensor(hall, encoder or resolver)?
- - How could you control the torque?
- - How could you control the RPM?
- Is it possible to drive a PMSM motor - here I am referring to an AC motor with permanent magnets(stator wounded, rotor with PM) - in a way that there is no externally mounted rotor position sensor(no hall, encoder, or resolver) using the scalar VFD method(V/f (Volts per frequency)) as one would typically drive an AC induction machine(stator wounded, rotor squirrel-cage)?
- The load that the PMSM motor would drive is a fan(yes, I know the torque-rpm curve of it is nonlinear rather than linear) so there is no stall-torque issue.
- If the presented scenario is possible, then the questions are:
- - Is the efficiency lower in this scenario in comparison with the one when there is a rotor position sensor(hall, encoder or resolver)?
- - How could you control the torque?
- - How could you control the RPM?
#2: Post edited
by
2kind
·
2021-09-22T20:12:04Z (about 3 years ago)
added detailed explanation
What are the drawbacks of driving the PMSM machine using VFD method? Let’s assume that torque vs. rpm of the load is linear.Is the efficiency in that case lower and if so, why exactly?
- Is it possible to drive a PMSM motor - here I am referring to an AC motor with permanent magnets(stator wounded, rotor with PM) - in a way that there is no externally mounted rotor position sensor(no hall, encoder, or resolver) using the variable frequency method as one would typically drive an AC induction machine(stator wounded, rotor squirrel-cage)?
- The load that the PMSM motor would drive is a fan(yes, I know the torque-rpm curve of it is nonlinear rather than linear) so there is no stall-torque issue.
- If the presented scenario is possible, then the questions are:
- - Is the efficiency lower in this scenario in comparison with the one when there is a rotor position sensor(hall, encoder or resolver)?
- - How could you control the torque?
- - How could you control the RPM?
#1: Initial revision
by
2kind
·
2021-09-21T19:35:44Z (about 3 years ago)
Driving PMSM machine as an AC induction machine
What are the drawbacks of driving the PMSM machine using VFD method? Let’s assume that torque vs. rpm of the load is linear. Is the efficiency in that case lower and if so, why exactly?