Control System Flashcards
consists of subsystems and processes assembled for the purpose
of obtaining a desired output with desired performance, given a specified input
control system
Two major measures of performance of Control System
Transient Response
Steady-state Error
If transient response is too fast, passenger
________ is sacrificed; if too slow, passenger
______ is sacrificed
- comfort
- Patience
Passenger safety and convenience would
be sacrificed if the elevator did not level
properly. What major measure of performance of control system is described?
Steady-state Error
we can
move large equipment with precision that
would otherwise be impossible, with?
Control System
Advantages of Control System
*Power Amplification
*Remote Control
*Convenience of input form
*Compensation for distrubance
converts the form of the input to that used by the controller.
Input Transducer
drives a process or a plant.
Contoller
The input is sometimes
called the
Reference
output can be
called the ___
Controlled Variable
are shown added to the controller and process outputs via summing junctions, which
yield the algebraic sum of their input signals using
associated signs
Disturbances
Input reference > Input Transducer> Controller> Summing Junction (D1)> Process/plant > Summing Junction (D2) > Output/Controlled Variable
Open-loop System
Input reference > Input Transducer> Controller> Summing Junction (D1)> Process/plant > Summing Junction (D2) > Output/Controlled Variable > Output Transducer/sensor > input summing junction > controller
Closed-loop System
System that cannot compensate for any disturbances
Open-loop System
Measures the output
response and converts it into the form used by the
controller.
output transducer, or sensor
Output temperature can be converted to a
voltage by
Thermistor
input position can be converted to a
voltage by
potentiometer or variable resistor
the return path from the output to the
summing junction.
feedback
path
output
signal is subtracted from the input signal
actuating signal
that is,
the transducer amplifies its input by 1
Unity Gain
the
actuating signal’s value is equal to the actual
difference between the input and the output.
Under this condition, the actuating signal is
called
error
compensates for
disturbances by measuring the output response,
feeding that measurement back through a feedback
path, and comparing that response to the input at
the summing junction
Closed-loop System
True or False?
Closed-loop systems, then, have the obvious
advantage of greater accuracy than open-loop
systems.
True
True or False?
Transient response and steady-state error can be
controlled more conveniently and with greater
flexibility in closed-loop systems
True
