Bedford B550-2001, Инструкция по установке и быстрому запуску

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Revision April 2008, ME13, SW V3.04
5-58
Pr. 119 Differential Time (D) Factory Setting: 0.00
Settings 0.00 to 1.00 sec Unit: 0.01sec
This parameter determines the damping effect for the PID feedback loop. If the
differential time is long, any oscillation will quickly subside. If the differential time is short,
the oscillation will subside slowly.
Pr. 120 Integration’s Upper Bound Frequency Factory Setting: 100 %
Settings 00 to 100 %
This parameter determines the integration’s upper frequency limit while operating in the
PID feedback loop. (Limit = Pr.03
×
Pr.120). During a fast Integration response, it is
possible for the frequency to surpass a reasonable point. This parameter will help limit
this frequency spike.
Pr. 121 One-Time Delay
Factory Setting: 0.0
Settings 0.0 to 2.5 sec Unit: 0.1sec
0.0 disable
PI Control: When controlled by P action only, deviations cannot be eliminated entirely.
To eliminate residual deviations, the P + I control is generally utilized. If PI is used, it
could eliminate the deviation caused by set-point changes and external interferences.
However, if the I-action is excessively powerful, it will delay the response to the variation.
The P-action could solely be used on a loading system that possesses integral
components.
PD Control: when a deviation occurs, the system immediately generates some
operational load that is greater than the single load generated by the D-action in order to
restrain the increment of the deviation. If the deviation is small, the effectiveness of the
P-action decreases as well. In some cases, control systems include integral component
loads, which are controlled by the P action only, and sometimes, if the integral component
is functioning, the whole system will be vibrating. In such cases, a PD control could be
used to lower the P-action’s vibration and to stabilize the system. In other words, this
control is good for use if the loads have no braking functions over the process.
PID Control: Uses the I-action to eliminate the deviation and the D-action to restrain the
vibration, and combine with the P action to construct the PID control. The PID control
method normally determines a control process with no deviations, high accuracy and
very stable.
B550
Series
sensorless vector frequency drive