Open Loop and Closed Loop Control System.pptx
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There are two main types of control systems: open-loop and closed-loop. Open-loop systems operate independently of feedback from the output, while closed-loop systems use feedback to automatically adjust the input based on the output. Some key differences are that open-loop systems are simpler and cheaper but less accurate, while closed-loop systems are more complex and costly but provide greater accuracy through feedback correction of errors. Examples of each type are given such as electric hand dryers for open-loop and automatic irons for closed-loop.
Open Loop and Closed Loop Control System.pptx
- 1. OPEN LOOP AND CLOSED LOOP SYSTEM
- 2. What is a Control System? A control system is defined as a system of devices that manages, commands, directs, or regulates the behavior of other devices or systems to achieve a desired result. A control system achieves this through control loops, which are a process designed to maintain a process variable at a desired set point.
- 3. Types of Control Systems There are various types of control systems, but all of them are created to control outputs. The system used for controlling the position, velocity, acceleration, temperature, pressure, voltage, and current, etc. are examples of control systems. There are mainly two types of control systems: 1.Open Loop Control System 2.Closed Loop Control System
- 4. Open Loop Control System A control system in which the control action is totally independent of the output of the system then it is called an open-loop control system. A manual control system is also an open-loop control system.
- 5. Practical Examples of Open Loop Control Systems Electric Hand Drier – Hot air (output) comes out as long as you keep your hand under the machine, irrespective of how much your hand is dried. Automatic Washing Machine – This machine runs according to the pre-set time irrespective of washing is completed or not. Bread Toaster – This machine runs as per adjusted time irrespective of toasting is completed or not. Automatic Tea/Coffee Maker – These machines also function for pre-adjusted time only. Timer Based Clothes Drier – This machine dries wet clothes for pre-adjusted time, it does not matter how much the clothes are dried. Light Switch – Lamps glow whenever the light switch is on irrespective of light is required or not. Volume on Stereo System – Volume is adjusted manually irrespective of output volume level.
- 6. Advantages of Open Loop Control Systems Simple in construction and design. Economical. Easy to maintain. Generally stable. Convenient to use as output is difficult to measure.
- 7. Disadvantages of Open Loop Control System Disadvantages of open-loop control systems include: • They are inaccurate. • They are unreliable. • Any change in output cannot be corrected automatically
- 8. Closed Loop Control System Control systems in which the output has an effect on the input quantity in such a manner that the input quantity will adjust itself based on the output generated is called a closed-loop control system.
- 9. Practical Examples of Closed Loop Control System Automatic Electric Iron Servo Voltage Stabilizer Water Level Controller Missile Launched and Auto Tracked by Radar An Air Conditioner Cooling System in Car
- 10. Advantages of Closed Loop Control System • Closed loop control systems are more accurate even in the presence of non- linearity. • Highly accurate as any error arising is corrected due to the presence of a feedback signal. • The bandwidth range is large. • Facilitates automation. • The sensitivity of the system may be made small to make the system more stable. • This system is less affected by noise.
- 11. Disadvantages of Closed Loop Control System • They are costlier. • They are complicated to design. • Required more maintenance. • Feedback leads to an oscillatory response. • Overall gain is reduced due to the presence of feedback. • Stability is the major problem and more care is needed to design a stable closed loop system.