Siemens SINAMICS S120 Function Manual page 89

Structure of V/f control
n*
Ramp- -function
generator
p1318 p0314
Fig. 3-15 Structure of V/f control
Prerequisites for V/f control
1. Initial commissioning has been performed:
The parameters for V/f control have been initialized with appropriate values.
2. Initial commissioning has not been performed:
The following relevant motor data must be checked and corrected:
-- r0313
-- p0314
-- p1318
-- p1319
-- p1326
-- p1327
V/f control can now be commissioned.
Note
With synchronous motors, V/f mode is normally only stable at low speeds. Higher
speeds can induce vibrations.
Commissioning V/f control
1. Verify the preconditions for V/f control mode.
2. Set p0311 ----> rated motor speed
3. Set p1300 = 0 ----> activates the function
4. Activate the enable signals for operation
5. Specify the speed setpoint ----> evaluate the diagnostic function
© Siemens AG, 2005. All rights reserved
SINAMICS S120 Function Manual, 06/05 Edition
p1317 = 1
p1327
p1319
Motor pole pair number, actual (or calculated)
Motor pole pair number
V/f control ramp-up/ramp-down time
V/f control voltage at zero frequency
V/f control programmable characteristic frequency 4
V/f control programmable characteristic voltage 4
Operating Modes
Converter
f*
V*
p1326
Servo control
uf_struktur.vsd
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