SuperFlow AutoDyn, Руководство оператора

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Control Modes
11-14 AutoDyn Chassis Dynamometer Operator Manual
Suggested Adjustment Technique
Use the minimum D-Gain possible to reach an acceptable reduction in ringing. Gradually
increase D-gain to damp oscillations and reduce overshoot. With a smaller I-Gain, the
overshoot of the set point will be minimal and can possibly can be eliminated. To check the
D-Gain adjustment, set the engine speed to midrange, then set the engine speed 100 rpm
higher (or set the wheel speed 5 mph higher). Check for surging, overshoot, and ringing at the
control valve position indicator (for a water brake).
11.5.9 D-Time
Allowed Values: 0-256
Determines the number of control system cyclic loops to use to determine the D-Term
(effectively creates a cumulative error based on control system cyclic time).
Suggested Value Range
Typically a 0 or low value (less than 10) for all system types.
Increasing the value will cause the D-Term to delay its effect.
Suggested Setup Prior to Adjustment: 0
What it Does
The D-Time parameter is used to control the size of the window over which the derivative is
measured. Since increasing or decreasing the window size also adjusts the resolution and
scale of the measurement, the D-Time cannot be adjusted without also affecting the D-Gain.
11.5.10 Filter
Allowed values:
0–7
Suggested Value Range:
Usually set to zero
What it Does
This term is the filter rate applied to the feedback signal. If the feedback signal in the control
loop is noisy, set this value fairly high. However, the filter adds delay to the feedback, so it
will slow down the system response. The filter algorithm is the same as those used for the
Open and Close rate parameters. The larger the number, the more filtering and delay.
Suggested Adjustment Technique
Leave the filter at zero unless a noise problem is apparent and cannot be corrected. In that
case, start with the lowest filter value for that channel and gradually increase the filter until
the problem does not affect control stability. The step response performance may be affected.