SuperFlow AutoDyn, Руководство оператора

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Overview
SuperFlow Technologies Group 11-3
11.1 Overview
This chapter defines the adjustable control parameters in WinDyn and provides suggestions for
tuning the control parameters to provide the best combination for stable, accurate tracking and
good step response to set point change.
Because the optimal set of control parameters may vary with engine types or vehicle types, it is
useful for the operator to have a good general understanding of how to quickly and effectively
tune the control parameters. However, keep in mind that no “auto-tuning” function is built into
the software. The best way to tune is through sustained trial and error methods.
The SuperFlow chassis dynamometer systems use digital Proportional, Integral, and Derivative
(PID) control parameters to provide electrical control signals to the eddy current absorber or AC
motor. Default parameters are provided with the system to handle the majority of vehicle
applications. You may adjust these parameters as necessary to adapt to a specific application.
Contact SuperFlow Customer Service for assistance.
11.2 Control Modes
A control mode refers to the output signal the system is controlling to. This could be the position
of a load control valve or throttle actuator, or it could be measured dynamometer speed or torque.
Even calculated values such as engine power can be used as a control mode.
The System Configuration Editor defines control modes. Up to five control modes are available for
each controller. Up to four controllers are currently supported by the system—two primary and
two secondary. Only the primary controllers are closed-loop controlled. However, any two of the
four controllers can be selected as primary. When activating both primary controllers
simultaneously, each must be assigned a different control mode (e.g., both throttle and load
cannot control to dynamometer speed at the same time).
Typical combinations are:
• Throttle controlling torque and Dyno (servo valve) controlling speed
• Throttle controlling speed and Dyno (servo valve) controlling torque
In control theory, the following terms are commonly used:
•
Set point:
The value of the desired control through a channel to, for example, engine speed
•
Feedback signal:
The actual measured value of that channel
•
Error:
The difference between the set point and the feedback signal
The two general types of control modes are
manual
and
servo
. The control system software was
designed to provide seamless mode switching. This means it is possible to switch from manual to
servo control mode or from one servo control mode to another while the engine is running. The
system will automatically determine the set point of the new control mode during the transition to
avoid abrupt changes in load or throttle position. This is a very effective way to troubleshoot a
control mode problem versus a water (or eddy current) system problem.