l
Via the P-factor, it is possible to define a quick reaction
to speed deviations, i.e. it is responsible for the immediate reaction of the
regulator. High values will result in a rough operation (vibrations).
l
The I-component is responsible for the accuracy of the
regulator. With the I-component, the regulator generates a continuously
increasing torque as long as the actual value deviates from the set value
(control difference). The increase rate of the torque depends on the I-portion.
The smaller the I-portion (integration time) is, the faster the torque is built
up. Values which are too low may result in instability of the control system
(vibrations).
The factory settings
are relatively "soft" so that the controller will work in the stable
range in any case. Generally, the basic factory settings are sufficient to
ensure a satisfactory travel and control bevaviour. The controller settings
must be optimized in special cases only.
Regulator structure
of the VVVF-controller:
In order to enable
optimum control of the whole travel range, several regulators are used:
Stopping regulator (Halte_P, Halte_I): Only used for
stopping the drive when the brake is opened
Speed regulator (n_P, n_I): Activated
during the travel operation. The amplification can be changed as from a
definable speed threshold (GA). The
amplification values for acceleration and deceleration can be set separately (K
START, K STOP).
Position regulator (LR): During
the deceleration operation, a position regulator is active.
Proportional
coefficient of the stillstand controller
Integration time of the
speed controller
Proportional coefficient of the stillstand controller
Integration time of
the stillstand controller
Switch-over threshold
for speed regulator amplification
Increase of starting
regulator's gain in refer to the speed regulator
Increase of stopping
regulator's gain in refer to the speed regulator
Torque pre-control
during acceleration and deceleration. Overshooting and undershooting after the
ramps can be eliminated with this parameter.
In most cases, the
default regulator settings ensure a good traveling behaviour of the system. For
this reason, these parameters should only be changed in exceptional cases.
For more details, please refer to the VVVF controller
manual.
Version 001 / Date: 07.03.2005