berger lahr 5 phase stepper + WS5-5

Dear friends,
I have a berger lahr 5 phase stepper motor RDM 5913/50-BL
Also I have a berger lahr driver WS5-5
I drive the driver using a PLC Siemens 224 using its high speed output
When i out pulses on the PWM/BOOST input of the driver, The motor vibrates but does not move.
Do I need to add any resistance or do anyone have a clue?
I need help urgently
Thank you

What you have dear friend is resonance. Frequencies at which the motor is incapaable of producing enough torque to rotate the shaft. There are two time constants which limit the operation of stepper motors. One is mechanical and the other is electrical. The mechanical time constant produces a resonance at between 200 and 300 Hz. (steps per second). The electrical time constant limits the maximum speed to about 5 KHz.

The way around the first area of zero torque is to ramp the velocity up and then back down. What you are after is a trapezoidal velocity profile. Once you've achieved that you can experiment with more exotic concepts in the motor control menagerie.

There is no known way around the second area of zero torque that I know of.

One more thing. The frequency of the first resonance will change depending on things like friction and the inertial load on the motor shaft. So any testing you do to locate the resonance should be done under realistic load conditions.

Thank you for your reply.
I already tried a range of frequencies. I tried one pulse per second (1Hz), I unloaded the motor shaft and I checked the wiring connection, but What happens that i feel "Knocks" inside the motor but the shaft does not move.
I tried high frequencies but what happens is that i hear whistle without any moving.
Is it a problem with the driver or the biasing level of the PWM or what?
Can anyone help?

amazingahmed said:

Thank you for your reply.
I already tried a range of frequencies. I tried one pulse per second (1Hz), I unloaded the motor shaft and I checked the wiring connection, but What happens that i feel "Knocks" inside the motor but the shaft does not move.
I tried high frequencies but what happens is that i hear whistle without any moving.
Is it a problem with the driver or the biasing level of the PWM or what?
Can anyone help?

Click to expand...

1Hz. should be far away from any resonance. Are you sure the controller is compatible with a 5-phase motor? You cannot use a controller designed for 4-phase motors on a 5-phase motor. You have to work out the commutation sequence for a 5-phase motor, and you'll see how different they are. If the phases are miswired then you also will get this problem.