Servo Motor

Not much to go on with. Like a name plate? What servo motor is it? Is it even an induction type motor for AC?

More information is needed.

It has been a while since I used a servo motor but I thought that they were two wire commutated DC motors when described by two words. Often a built in hall sensor circuitry would control the commutation if brushless operation is desired.

By the very name a servomotor requires feedback, an induction motor does not. Thus an induction motor can be part of a servomotor system but a commutated DC motor can be part of a servomotor, too.

If feedback or encoder is separate from the motor, perhaps the motor can be used as and induction motor if not a dc motor type.

Is this not a stepping motor? You can make step motors run on AC with an additional capacitor.

Can you tell us what is written on the face plate?

brgds

Snel

I want to see how one wires a five phase stepping motor directly with three phase AC power.

We just do not know enough information and the OP is now mute.

some 2-phase steppers (probably not the ones with 5 wires) will turn on one phase AC with a capacitor as a "running" cap. Eppur si muove, it turns, not very useful perhaps.

This OP is probably sleeping, too.

brgds

Snel

If it is a 3PH servomotor and its rated voltage meets your supply lines, yes you can. you'll have it running at a single sepeed though.

In the past I did a test with a 0.75 kW 6 pole Siemens servo motor. The rotor of this servomotor was equipped with permanent magnets. The stator had a 3 phase winding connected in wye.

As power supply a 3 phase variable transformer (variac) was used.

When I slowly increased the voltage, the stator current also gradely increased, but the motor would not turn only shake. Because I didn't want to harm the rotor magnets, I stopped the test at a safe current.

Probably because of the permanent magnets, at the moment the rotor is starting to turn around, the stator is working as a generator. The generated voltage will be opposed to the supply voltage.

Two power sources working against each other ? Someone has a better explanation?

You describe the known effect of Back EMF. Back EMF is what changes the current phase angle.

It sounds more like your gradual raising of voltage did not overcome stiction and rotor inertia.