Q:

What determines if a system is closed loop or open loop?

A:

Quick Answer

Closed-loop and open-loop systems are two different control types. Control theory is an interdisciplinary branch of engineering and mathematics that deals with the behavior of dynamical systems with inputs. Systems in which the output quantity has no effect on the processes' input quantity are open-loop control systems. Systems in which the output quantity and negative feedback affect the processes' input quantity are closed-loop control systems.

Know More

Full Answer

Closed-loop control systems have a closed control loop, can counteract against disturbances via negative feedback and have the potential to become unstable if the controlled variable does not fade. Open-loop control systems show an open-loop action and can only counteract against disturbances for which they have been designed to counteract. Germany's Ruhr University Bochum explains this closed-loop versus open-loop control following a simple room heating system example. An open-loop control for a room heating system has an outdoor thermostat fed to a control device. When outdoor temperatures drop to a designated level, the control device triggers the heat source to warm the indoor room temperature. If a window is opened and the room temperature drops, this disturbance goes undetected at the control device because the outdoor temperature influences the indoor room temperature. If the thermostat and control device are moved inside the room, the system becomes a closed-loop control design. The indoor room temperature is measured and determined by the set-point value of the thermostat. If a window is opened, this disturbance is detected by the controller and removed. This disturbance detection and control produce a negative feedback loop.

Learn more about Electricity
Sources:

Related Questions

  • Q:

    What was the open field system?

    A:

    The open field system was a system of agriculture in which large fields were divided into strips that were farmed by individual peasants. This form of farming predominated in Europe from the middle ages until the 1800s.

    Full Answer >
    Filed Under:
  • Q:

    What is a open system in biology?

    A:

    In the biological world, an open system is one in which materials and energy are transferred between organisms and the exterior environment. In an open system, there is some type of boundary that allows energy or materials to cross over for the purpose of growth and change.

    Full Answer >
    Filed Under:
  • Q:

    What is RMS voltage?

    A:

    Root mean square voltage is a statistical measure of how much alternating current power is needed to produce a similar heating effect to an equal direct current power. Root mean square can be found by taking the square root of the average of the squares of the measure values.

    Full Answer >
    Filed Under:
  • Q:

    How does a tunnel diode work?

    A:

    A tunnel diode works by creating an area of negative resistance for electrons to penetrate the potential barrier of a semiconductor junction. The mechanism of a tunnel diode is based on the principle of quantum mechanical tunneling where a particle "tunnels" through a barrier, which it cannot otherwise cross.

    Full Answer >
    Filed Under:

Explore