Eaton 9000X - Closed Loop Vector Control Manual Tuning (SPX9000 Only)

9000X AF Drives User Manual
MN04001004E
For more information visit: www.eaton.com 6-11
June 2009
Closed Loop Vector Control Manual Tuning (SPX9000 Only)
For some non-standard motors the auto-tune is not sufficient. Closed lop control mode is
used, when enhanced performance near zero speed and better steady stats and dynamic
speed accuracy at higher speeds are needed.
Tuning Steps
Set the motor nameplate values.
Nominal voltage of motor P1.1.6
Nominal frequency of motor P1.1.7
Nominal speed of motor P1.1.8
Nominal current of motor P1.1.9
Motor Power Factor (Cos Phi) P1.1.10
Check encoder Pulse/Revolution rate and set this value to expander menu P6.3.1.1.
Parameter is only visible if OPTA4 or OPTA5 is installed to slot C.
Set motor control mode to open loop frequency control (P1.6.1 = 0).
Run the motor unloaded at 2/3 rated speed using a frequency reference. Read the motor
current from the monitoring menu (V1.4) or use 9000X Drive for monitoring. This current is
the motor magnetizing current. This value should match a nameplate magnetizing current
value if given.
Check the expander board menu (monitoring page V6.3.2.1), that the encoder frequency is
approximately the same as the output frequency. Check also, that the direction is correct. If
the encoder frequency direction is opposite the output frequency (negative value), change
the motor phase order to encoder connection. The expander board menu also has a
parameter to invert the signal if rewiring is not an option.
Set motor control mode to closed loop (P1.6.1 = 3 or 4).
Set the motor magnetizing current P1.6.17.1 (measured in step 4).
Fine Tuning
Tune parameter P1.6.17.6 (Slip Adjust) to get the motor voltage slightly above the linear
V/f-curve when motor is loaded and slightly below when motor is generating.
Using the linear V/f-curve (P1.6.3 = 0), run the motor in frequency control mode (P1.6.1 = 0) at
about 2/3 of the motor nominal frequency and check motor voltage (V7.7).
At 40 Hz, voltage should be 40/60*460V = 307V.
Run the motor in closed loop control mode with same reference and check the motor voltage.
Adjust P1.6.17.6 (Slip Adjust) so that motor voltage is slightly above the linear
V/f-curve. If motor voltage is low, decrease the value of Slip Adjust (P1.6.17.6).