Siemens 440 operating instructions Quick commissioning routine, Motor data identification routine

Issue 10/06 6 Commissioning

The procedure to manually determine the magnetizing current and to re-calculate the equivalent circuit diagram data when the drive is operated with closed-loop vector control (P1300 = 20/21) is shown in the following.

START

Quick

commissioning

Motor data

identification

Operation under

no-load conditions

Criterium

fulfilled ?

no yes

P0320 = ...

P0340 = 1

END

Quick commissioning routine

Using the quick commissioning routine the frequency inverter is adapted to the motor and important technology parameters are set.

Motor data identification routine

Using the motor data identification routine motor equivalent circuit diagram data is determined using a measuring technique.

Determining the magnetizing current

In order to determine the magnetizing current (P0320/r0331), the motor should be accelerated up to approximately 80% of its rated speed under no-load operating conditions.

In so doing, the following conditions must be carefully maintained:

−the vector control must be activated, P1300 = 20.21

−no field weakening (r0056.8 = 0)

−flux setpoint, r1598 = 100 %

−no efficiency optimization, P1580 = 0 %

No-load operation means that the motor is operated without a load (i.e. no coupled driven machine).

Under steady-state conditions, a current r0027 is obtained that approximately corresponds to the rated magnetizing current r0331. (the current is always less than the no-load current for a pure V/f control).

Measuring and entering the magnetizing current and therefore the associated new calculation of the equivalent circuit diagram data of the motor is an iterative procedure. It must be repeated at least 2-3 times until the following criteria are fulfilled:

−The more accurate the value of the magnetizing current that was entered, the better the flux setpoint (r1598=100%) matches the flux actual value (r0084=96..104%) of the observer model.

−The output Xm adaptation (r1787) of the observer model should be as low as possible. Good values lie between 1-5%.The less that the Xh adaptation of the observer must operate, the sensitivity of the motor parameters after power failures are that much less sensitive.

NOTE

In order to display r0084 at the BOP/AOP, the LEVEL 4 parameters must be enabled using service parameter P3950=46.

Calculating P0320	0
Now, the new value can be entered in P0320 from the determined flux-
generating current component r0029 by applying the following equation.
P0320 = r0029 * 100 / P0305
Calculating the motor parameters	0

The values of the motor equivalent circuit diagram data are calculated from the entered rating plate data. In addition, the parameters of the controls are pre-set (subsequently optimized) (P0340 = 3).

MICROMASTER 440	33
Operating Instructions (Compact)