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KEB COMBIVERT F4-F
12
Name: Basis
11.05.99
Chapter
Section
Page
Date
©
KEB Antriebstechnik, 1999
All Rights reserved
Functional Description
Motor Data and Controller Adjustment
KP flux (CS.19)
KI flux (CS.20)
Magnetizing current
limit (CS.21)
In the base speed range the maximum torque is mainly limited by the hardware current
limits of the inverter. For a stable operation the control requires voltage reserves in
order to balance currents at any time, therefore the torque that can be reached in the
higher speed range is limited by the output voltage. The limit characteristic is adjusted
correctly when a voltage reserve of approx. 5…10 % of the rated voltage is available
at every operating point.
In this parameter the speed is adjusted at which the field weakening operation starts.
In this parameter the field weakening characteristic is adjusted. The value of 1 means
that the flow is lowered after an 1/n function.
With the parameters dr.20, dr.21 the flow characteristic can be adapted to the motor.
Corner speed field weakening
(dr.19)
Field weakening curve (dr.20)
Flux adaption factor (dr.21)
1
2
dr. 20 = 1
dr. 20 < 1
dr. 20 >1
Fig. 6.5.15 Flux lowering
The flux controller is designed as PI-controller. The factors are adjusted with CS.19
and CS.20, CS.21 contains the limitation. With the setting KP flow (CS.19) = 0 the
controller is deactivated. For most applications it is not necessary to activate the flow
controller. Only in the case of short acceleration times and setpoint speed values
within the field weakening range the drive performance can be optimized by activating
the flow controller. Sensible starting values for the parameterizing are: CS.19 = 100 /
CS.20 = 20 / CS.21 = Rated motor current
Change to max. voltage control when the motor parameter adaption is active
(CS.22 = 1). The voltage in the field weakening range is limited then to 100%. In this
case useful starting values for the parameterization are: CS.19 = 2000 / CS.20 = 256
/ CS.21 = rated motor current.
Flux
Flux adaption
(dr.21)
Gain factor
field weakening
(dr.20)
Actual speed (ru.01) + slip
Corner speed field weakening
(dr.19)
6.5.15 Flux Lowering
Calculation
6.5.16 Flux Control/Max.
Voltage Control