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Functions
7.6 Motor control
Inverter with CU240B-2 and CU240E-2 Control Units
Operating Instructions, 07/2010, FW 4.3.2, A5E02299792B AA
173
Table 7- 14 Optimizing the starting characteristics for a linear characteristic
Parameter Description
P1310
Permanent voltage boost (factory setting 50 %)
The voltage boost is effective from standstill up to the rated speed.
It is at its highest at zero speed and reduces continuously as the speed increases.
Value of voltage boost at zero speed in V:
1.732 × rated motor current (p0305) × stator resistance (r0395) × p1310 / 100 %.
P1311
Voltage boost on acceleration
The voltage boost on acceleration is independent of speed and occurs when the
setpoint is increased. It disappears as soon as the setpoint is reached.
Value in V: 1.732 × rated motor current (p0305) × stator resistance (r0395) x p1311 /
100 %
P1312
Voltage boost at start up
The voltage boost during start-up results in an additional voltage boost during power-
up, but only for the first time the motor accelerates after having been switched on.
Value in V: 1.732 × rated motor current (p0305) × stator resistance (r0395) x p1312 /
100 %
You will find more information about this function in the parameter list and in function
diagram 6300 of the List Manual.
7.6.2
Vector control
7.6.2.1
Properties of vector control
Using a motor model, the vector control calculates the load and the motor slip. As a result of
this calculation, the inverter controls its output voltage and frequency so that the motor
speed follows the setpoint, independent of the motor load.
Vector control is possible without directly measuring the motor speed. This closed-loop
control is also known as sensorless vector control.
7.6.2.2
Commissioning vector control
Vector control only functions error-free if, during the basic commissioning, the motor data
were correctly parameterized and a motor data identification was performed with the motor in
the cold state.
You can find the basic commissioning in the following sections:
● Commissioning with the BOP-2 (Page 68)
● Commissioning with STARTER (Page 73)