SuperFlow AutoDyn, Руководство оператора

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Control Mode Parameters
SuperFlow Technologies Group 11-13
11.5.7 I-Time
Allowed Values:
0–256
Determines the number of control system cyclic loops to use to determine the I-Term.
Suggested Value Range
Typically a 0 or low value (less than 10) for all system types.
Increasing the value will cause the I-Term to delay its effect.
Suggested Setup Prior to Adjustment: 0
What it Does
The I-Time parameter determines the time base within which the error integrates. It is used to
define the rate in which the integrator is processed. This time determines how often the integrator
is operated during the controller update. For example, a setting of 5 would cause the integrator to
be updated every 5th time. This parameter is used to slow down the integrator. The wider this
time base, the slower the system response will be, making the system more stable but also
increasing overcompensation of the error. On systems with lots of system inertia (= slower
response) such as chassis dynamometer, the integrator should work within a fairly narrow time
band.
11.5.8 D-Gain
D
term
= ((Error
Current
– Error
A_While_Ago
) * D
gain_value
)
Allowed values:
Any floating point value
Suggested Value Range
• 4 to 20 for engine dynos controlling to engine speed
• 0.025 to 5000 for a CycleDyn controlling to vehicle speed
• 0 to 5000 for an AutoDyn controlling to vehicle speed
Suggested Setup Prior to Adjustment
• Engine Dyno controlling to engine speed D-Gain = 1
• Chassis Dyno controlling vehicle speed D-Gain = 5000
• Chassis Dyno controlling roll torque D-Gain = 0.01
What it Does
The D-Gain helps stabilize the control channel to the set point. It helps reduce the ringing,
oscillations and instability associated with high P-Gain and high I-Gain. The D-Gain is
proportional to the rate of change of the engine rpm or wheel speed. The D-Gain determines
to what extent error rate of change influences control to the dyno or to the throttle. If the D-
Gain is too low, the control system will have excessive overshoot and will surge for a long
time before settling down. If D-Gain is too high, the system will take too long to reach the set
point and may be oversensitive to changing speed, thus making the system unstable.