Siemens SINAMICS G120XA, Руководство по эксплуатации

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Note
In the field weakening range, it must be expected that the control dynamic performance is somewhat restricted due to
the limited possibilities of controlling/adjusting the voltage. This can be improved by increasing the voltage reserve.
Increasing the reserve reduces the steady-state maximum output voltage (r0071).
p1578[0...n] Flux reduction flux decrease time constant / Flux red dec T
Access level: 3 Calculated: CALC_MOD_CON Data type: FloatingPoint32
Can be changed: T, U Scaling: - Dynamic index: DDS, p0180
Unit group: - Unit selection: - Function diagram: 6791
Min:
20 [ms] Max:
5000 [ms] Factory setting:
200 [ms]
Description: The following applies for a synchronous reluctance motor:
Sets the time constant for reducing the flux setpoint for a load-dependent optimum flux characteristic.
Dependency: See also: p1579
Note
To avoid remagnetization processes for load-dependent flux characteristics and for fast load changes, the time
constant to reduce the flux setpoint must be set to an appropriately high value.
As a consequence, it is preset with a multiple of the time constant used for the flux build up.
p1579[0...n] Flux reduction flux build-up time constant / Flux red incr T
Access level: 3 Calculated: CALC_MOD_CON Data type: FloatingPoint32
Can be changed: T, U Scaling: - Dynamic index: DDS, p0180
Unit group: - Unit selection: - Function diagram: 6791
Min:
0 [ms] Max:
5000 [ms] Factory setting:
4 [ms]
Description: The following applies for a synchronous reluctance motor:
Sets the time constant for establishing the flux setpoint for a load-dependent optimum flux characteristic.
Dependency: See also: p1578
Note
To quickly establish the flux for torque changes, an appropriately short time constant for the flux build-up must be
selected.
It is preset with the inverse value of the rated motor frequency (p0310).
p1580[0...n] Efficiency optimization / Efficiency opt.
Access level: 3 Calculated:
CALC_MOD_LIM_REF
Data type: FloatingPoint32
Can be changed: T, U Scaling: - Dynamic index: DDS, p0180
Unit group: - Unit selection: - Function diagram: 6722
Min:
0 [%] Max:
100 [%] Factory setting:
0 [%]
Description: Sets the efficiency optimization.
When optimizing the efficiency, the flux setpoint of the closed-loop control is adapted as a function of the load.
For p1580 = 100 %, under no-load operating conditions, the flux setpoint is reduced to 50 % of the rated motor flux.
Note
It only makes sense to activate this function if the dynamic response requirements of the speed controller are low.
In order to avoid oscillations, if required, the speed controller parameters should be adapted (increase Tn, reduce Kp).
Further, the smoothing time of the flux setpoint filter (p1582) should be increased.
Parameters
7.3 Parameters
SINAMICS G120XA converter
530
Operating Instructions, 03/2019, FW V1.0, A5E44751205B AB