Search results
Results from the WOW.Com Content Network
The control system performance can be improved by combining the feedback (or closed-loop) control of a PID controller with feed-forward (or open-loop) control. Knowledge about the system (such as the desired acceleration and inertia) can be fed forward and combined with the PID output to improve the overall system performance.
This "cascade" system matches the form in Equation , and so the single-integrator backstepping procedure leads to the stabilizing control law in Equation . That is, if we feed back states z 1 {\displaystyle z_{1}} and x to input u 1 {\displaystyle u_{1}} according to the control law
The control is designed as a cascade control and has an external force control loop and an internal position control loop. As shown in the following figure, a corresponding infeed correction is calculated from the difference between the nominal and actual force.
For example, under certain conditions a large power grid can collapse after the failure of a single transformer. Monitoring the operation of a system, in real-time, and judicious disconnection of parts can help stop a cascade. Another common technique is to calculate a safety margin for the system by computer simulation of possible failures, to ...
A control system manages, commands, directs, or regulates the behavior of other devices or systems using control loops. It can range from a single home heating controller using a thermostat controlling a domestic boiler to large industrial control systems which are used for controlling processes or machines.
If all subsystems of the above system are ISS, then the whole cascade interconnection is also ISS. [7] [4] In contrast to cascades of ISS systems, the cascade interconnection of 0-GAS systems is in general not 0-GAS. The following example illustrates this fact. Consider a system given by
Examples are the cruise control example above, or an audio system, in which the control input is the input audio signal and the output is the sound waves from the speaker. Multiple-input multiple-output (MIMO) – These are found in more complicated systems.
A pure feed-forward system is different from a homeostatic control system, which has the function of keeping the body's internal environment 'steady' or in a 'prolonged steady state of readiness.' A homeostatic control system relies mainly on feedback (especially negative), in addition to the feedforward elements of the system.