Start PMSM uncontrolled

Question

Dear PLECS Team

I want to start my PMSM machine with the following voltage (Vab_startUp -> alpha-beta coordinate system) uncontrolled. The motor start can be divided into three steps:

1. constant phase current (t = 0...1.08).

• The rotor should align itself.

2. V/f ramp (t = 1.08.... 2.08)

• The motor should accelerate to a constant speed.

3. V and f are constant (t = 2.08... 5)

• The motor should keep its speed constant.

As can be seen in the simulation, my motor does not move.
Why is that so?

In the attachment you will find the following:
- Schematic (.pdf)
- Scope (.pdf)

I would be very happy if you can help me. If you need the original PLECS Modell, let me know.

Best regards
Raphael

Answer 1

The schematic shows the machine's rotor is directly connected to the rotational reference frame, essentially fixing the rotor position to zero degrees.  If you remove the connection the motor should spin.

Comments

Now it works thanks a lot. Now I know what the Rotational Reference means.