SuperFlow AutoDyn, Руководство оператора

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Selective Control
SuperFlow Technologies Group 11-5
normal phenomenon. The control parameters can be adjusted for faster or slower system response
and more or less overshoot.
A throttle controller can also be used in speed control mode. The throttle is then modulated to
reach the desired dynamometer speed independently of the dynamometer load applied. This test
mode can be used to simulate cruise control operation.
Torque Control Mode
This is the most common throttle control mode used during automated tests. The throttle actuator
is controlled by the system to maintain a specific dynamometer torque (the set point). The throttle
position modulates so the torque produced by the engine matches the set point. This typically
results in torque control to better than
± 1 lb • ft (N-m) of the set point.
A typical application for a combination of throttle controlling torque and load controlling speed is
the mapping of an engine. By stepping through the torque range for each speed point, the
complete engine map can be covered in the shortest possible time.
WARNING: Always turn the dynamometer load control on (in speed mode) before you
switch the throttle to torque mode. If no load is applied by the dynamometer, the throttle
controller will immediately open the throttle fully in an attempt to achieve the desired
torque. This will result in an immediate engine overspeed condition.
The load (servo valve) controller can also be used in torque control mode. The dynamometer load
then modulates to reach the desired torque independently of the throttle position. This test mode
is used to apply a constant torque to accessory belts or chain drives.
Other Control Modes
Additional control modes may have been defined for systems used in special applications. It is
also possible for dyno operators to define their own control modes. Examples are:
• Horsepower
• Throttle position
• Manifold (boost) pressure
• Engine speed (for engine dynamometers)
11.3 Selective Control
When system power is switched on, it defaults to the manual control mode (also called position
control mode). The operator can then select servo control mode for either controller in any
available control mode.
In each control mode, it is possible to modify the control output signal using the handheld
controller. The ranges for each control mode of the encoder can also be changed to suit the user's
needs.