One or more of these actions can be selectively utilized, depending on the variables that are being controlled. In this chapter, we will discuss the basic controllers such as the prop integral and derivative actions is more commonly referred as PID action There are several ways to tune the parameters of a PID controller. PID controllers are best used in systems which have a relatively small mass and those which react quickly to changes in the energy added to the process. a. can not determine as to how many roots of the characteristics equation have positive real roots. PID control combines the advantages of proportional, derivative and integral control actions. The PID controller takes control systems to the next level. Explanation: No explanation is available for this question! A PID controller has some limitations also apart from being one of the best controllers in control action system. Question 1. Home >> Category >> Electronic Engineering (MCQ) questions & answers >> Frequency Domain Analysis; 1) In frequency response, the resonance frequency is basically a measure of _____ of response. In early days PID controller was used as a mechanical device. For each, name the procedure and explain how the given measured information is used to pick the parameters of the PID controller. Fixed control point c. Frequency converter d. Final control element. 13. Join the global Raspberry Pi community. You can change your ad preferences anytime. Examine the closed-loop step response (reference tracking) of the controlled system. B) Shortest service time first 16. Integral action or reset action is used in conjunction with proportional action, to remove offset from the system. These short objective type questions with answers are very important for Board exams as well as competitive exams. In each application, coeffi… Many complex electronic systems are provided with a PID control loop. Electrical4U is dedicated to the teaching and sharing of all things related to electrical and electronics engineering. PD action is employed when a) When the system changes are small b) Improve the recovery time c)When system lags are high d) All above 25.PID controller is used when system requires a)System changes are small b)Offset must be eliminated c)Fast recovery time d) All above 18. The most popular type of controller is PID which is an acronym for Proportional, Integral and Derivative.In this Arduino PID control tutorial, I will show you how you can employ such a controller in your project. technique has to be applied in a closed loop system because this technique requires the use of the PID controller. In modern days PID controllers are used in PLC (programmable logic controllers) in the industry. Find the IMC controller transfer function, q(s), which includes a filter, f(s), to make q(s) semi-proper or to give it derivative action (order of the numerator of q(s) is one order greater that the denominator of q(s)). We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. See our User Agreement and Privacy Policy. Ziegler-Nichols open-loop tuning equations for the appropriate controller (P, PI, or PID) to calculate the controller constants. D) All i, ii and iii 18. The IMC-Based PID Control Design Procedure The following steps are used in the IMC-based PID control system design 1 . PID controllers are considered to be the best controller in the control system family. Answer: a. It affects rise time, settling time and overshoot and also the steady state error. So PID controller becomes sometimes PI (proportion-integral), PD (proportional-derivative) or even P or I. Programmable Logic Controller (PLC) Interview Questions ; Question 8. A previous post about the Derivative Term focused on its weaknesses. The PI controller is the most popular variation, even more than full PID controllers. Clipping is a handy way to collect important slides you want to go back to later. Proportional Integral Control (PI) PI control is a combination of proportional and integral control:... Eq. Main disadvantage is the feedback path. Here controller output varies at a rate proportional to the deviation between measured and desired value. PID Controller … The feedforward variable together with the output of the integral member can, on the other hand, help the he… This type of control is also termed as three-term control, and is implemented by a PID Controller. (22) In the Laplace domain this can be written as... Eq. On-off control is usually used where a precise control is not necessary, in systems which cannot handle having the energy turned on and off frequently, where the mass of the system is so great that temperatures change extremely slowly, or for a temperature alarm. Proportional control system is complicated and costly. A different speed (that is, a time constant) of the heating and cooling processes needs dynamical adaptation of the PID constants according to the temperature setpoint value. As the name suggests, PID algorithm consists of three basic coefficients; proportional, integral and derivative which are varied to get optimal response. There is only one energy storage in process (capacitive or inductive) 4. Looks like you’ve clipped this slide to already. When more functionality is required than device–based function blocks provide or when function blocks are needed which are not included in devices, DeltaV controllers are used because they contain In the design process we will assume a single-input, single-output plant as described by the following transfer function. If the set point is changed the derivative action can cause large and unstable changes in output. Therefore, the actuating signal for PID control is: The Laplace transform of the actuating signal incorporating PID control is. Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. These controllers, specifically the P, PD, PI, and PID controllers are very common in the production of physical systems, but as we will see they each carry several drawbacks. When a step-change in setpoint is applied to such a closed-loop system, the controlled variable with exhibit a. Overdamped response b. What is the relationship between the steady-state error, gain and the tendency of oscillations when the controller is supposed to be under the proportional action? Expert systems were the predecessor of the current day artificial intelligence, deep learning and machine learning systems. PID Controller Design, Tuning, and Troubleshooting Performance Criteria For Closed-Loop Systems • The function of a feedback control system is to ensure that the closed loop system has desirable dynamic and steady-state response characteristics. The proportional, derivative and integral parameters can be expressed as – Kp, Kd and Ki. PID control is a feedback mechanism which is used in control system. The derivative control action is typically used when controlling, but rarely used when controlling. Effect of feedback on the plant is to. A) Double buffering 12. PID Controller is a most common control algorithm used in industrial automation & applications and more than 95% of the industrial controllers are of PID type. Part 1 of this series (Control Engineering, Nov. 2012) looked at several issues that limit the performance of the theoretical PID algorithm in real-world applications of feedback control.. All of these problems are exacerbated by uncertainty. By calculating and controlling three parameters – the proportional, integral and derivative of how much a process variable deviates from the desired set point value – we can achieve different control actions for specific work. As noted, the primary challenge associated with the use of Derivative and PID Control is the volatility of the controller’s response when in the presence of noise. It can provide a controlled — almost intelligent — drive for systems. 1. APIdays Paris 2019 - Innovation @ scale, APIs as Digital Factories' New Machi... No public clipboards found for this slide. We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites. C_pi is a pid controller object that represents a PI controller. Collection of Many MCQ and answers for Tikrit University students. By controlling the three parameters – proportional, integral and derivative we can achieve different control actions for specific work. If you continue browsing the site, you agree to the use of cookies on this website. Once the control system implements the heating model, its output can be used suitably as a feedforward variable. C) RAID Level 2 20. We will now examine the individual components of the PID system. Answer : These controllers are used based on the control system, the user can be used the controller to regulate the method. The closed-loop transfer function of the given system with a PID controller is: (10) After several iterations of tuning, the gains = 350, = 300, and = 50 provided the desired response. Artificial Intelligence and Expert Systems are capable of expressing and reasoning about some domain of knowledge. Gain at which system produces constant oscillations is called ultimate gain (Ku) and the period of oscillations is called the ultimate period (Pc). The time-honored Ziegler-Nichols tuning rule [2,3] ("Z-N rule"), as introduced in the 1940s, had a large impact in making PID feedback controls acceptable to control engineers.PID was known, but applied only reluctantly because of stability concerns. If operating properly, automatic control will always: a. There are some control actions which can be achieved by using any of the two parameters of the PID controller. This step is necessary to understand the entire PID system. For example, as an aircraft flies, its mass will slowly decrease as a result of fuel consumption; a control law is needed that adapts itself to … Before we start to define the parameters of a PID controller, we shall see what a closed loop system is and some of the terminologies associated with it. 2. Fast recovery time. 9. A control system which has become commonplace in the automotive industry is the cruise control system: an output is programmed by the driver, and the control system has to manage all of the vehicle readings in order to maintain velocity. The block diagram on the right shows the principles of how these terms are generated and applied. The steps for tuning a PID controller via the 2 nd method are as follows; Using only proportional feedback control: 1. a) Forces b) Friction c) Stored energy d) Coupling Ans: (c) 2. Nicholas Minorsky published the theoretical analysis paper on PID controller. Large disturbances and noise are present during operation of the process 3. The PID controller looks at the setpoint and compares it with the actual value of the Process Variable (PV). As the name implies, a temperature controller - often called a PID controller is an instrument used to control temperature. The difference between old and modern controller 1.Old Type Controller . Proportional Control: Here actuating signal for the control action in a control system is proportional to the error signal. This technique has to be applied in a closed loop system because this technique requires the use of the PID controller. Let us discuss these control actions in brief. To confirm, enter the following commands to an m-file and run it in the command window. In digital governor, digital controller is used in turbine governing system. a. Using the PID Advanced function . Therefore, the actuating signal for derivative control action is given by, Integral Control: For integral control action the actuating signal consists of proportional error signal added with integral of the error signal. The block diagrams below show the difference. which will improve your skill. In this page you can learn various important control system multiple choice questions answers, mcq on control system, short questions and answers on control system, sloved control system objective questions answers etc. The criterion of stability for closed-loop systems does not require calculation of the actual values of the roots of the characteristic polynomial. Modern micro-processor controllers, however, use a lot of PID control but in a different way. PID control is applicable to many control actions but it does not perform well in case of optimal control. Before explaining PID Controller, let's revise about Control System.There are two types of systems; open loop system and close loop system. Small amount of noise can cause great change in the output. Proportional control system is not suitable for pressure temperature and flow control problems 3. Operating System Questions & Answers – Processes This set of Operating System Multiple Choice Questions & Answers (MCQs) focuses on “Processes”. Fast response of the system is not required 2. Hybrid control is a term given to a control strategy that incorporates function blocks running in both field devices and a DeltaV controller. Mechanical controllers include spring, lever or mass. Otherwise stated, we will attempt to control the pendulum's angle without regard for the cart's position. Please don’t skip this section; you must know how the individual components function to understand the whole system. It is based on knowledge acquired from an expert. Advantages of a PLC Control System Faster Response Time: PLCs operate in real-time which means that an event taking place in the field will result in an operation or output taking place. If there are sudden disturbance, the proportional control system takes time to stabilize. The proportional term applies appropriate proportional changes for error (which is the difference between the set point and process variable) to the control output. Manual tuning methods are iterative and time-consuming, and if used on hardware, they can cause damage. Derivative Control: The actuating signal consists of proportional error signal added with derivative of the error signal. Why is plagiarism such a big deal in the university context? Answer Explanation ANSWER: Speed. 1. There are large transport delays in the system. It only requires that we know if any root is to the right of the imaginary axis. If you continue browsing the site, you agree to the use of cookies on this website. PID Controller Multiple Choice Questions and Answers for competitive exams. C) RAID Level 6. B) Single buffer 11. Top PID Controller Multiple Choice Questions and answers for industrial automation engineers and control system engineers.. PID Controllers Multiple Choice Questions. The purpose of a cruise control system is to accurately maintain a speed set by the driver without any outside intervention by controlling the throttle-accelerator pedal linkage. +9647703057076 Digital control hardware running an application programme accomplishes the required control function with this system. But while changing the controller from manual to auto, the controller setpoint is to match to the process variable and then auto-manual switch is transferred. criterion is not applicable to systems with polynomial characteristic equation. When Proportional (p) Controller Is Used ? Answer : PID controller is used when system requires: System changes are small. There are a number of different standard types of control systems that have been studied extensively. Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Full disclaimer here. Speed b. 1.Transient response in the system is basically due to. Multiple Choice Question (MCQ) of Electronics page-17:241. This type of control is also termed as three term control. D) Circular SCAN 17. Increase K p Figure-10: Closed loop control system with PID Controller These were pneumatic controllers as they were compressed by air. Multiple Choice Question (MCQ) of Control Systems page-1. An on-off control method is the simplest type of device used for temperature control. Two parameters can work while keeping the third one to zero. c) The saturation voltage V CE for silicon transistor is same as that for germanium. All these three parameters have an effect on the closed loop control system. Flow rate controller b. A) seek time 13. Which of the following statement is true? The steps for tuning a PID controller via the 2 It is recommended in systems where the load changes often and the controller is expected to compensate automatically due to frequent changes in setpoint, the amount of energy available, or the mass to be controlled. Time response of discrete systems 4th lecture, Customer Code: Creating a Company Customers Love, Be A Great Product Leader (Amplify, Oct 2019), Trillion Dollar Coach Book (Bill Campbell). In this section of Operating System Process Management.it contain Operating System Process Management - Process Creation MCQs (Multiple Choice Questions Answers).All the MCQs (Multiple Choice Question Answers) requires in detain reading of Operating System subject as the hardness level of MCQs have been kept to advanced level. A) RAID Level 0 19. The Raspberry Pi is a tiny and affordable computer that you can use to learn programming through fun, practical projects. Multiple Choice Questions and Answers on Control Systems Multiple Choice Questions and Answers By Sasmita January 9, 2020 1) Which terminology deals with the excitation or stimulus applied to the system from an external source for the generation of an output? This type of control is also termed as three-term control, and is implemented by a PID Controller. The derivative term D is responsible for noise measurement while the integral term is meant for reaching the targeted value of the system. By Kong Wai Weng RH2T Mag, Vol.4, Mar 2010 PID control system is one of the most mature and commonly used control strategies in the industrial for decades thanks to its simple but effective algorithm. These short solved questions or quizzes are provided by Gkseries. The PID control is the main control technology used in the plant. Sometimes the controller lacks sufficient information about the controlled process to know how much and how long to apply a control effort. They involve the following procedures. The following list of topics deals with Multiple choice question (MCQ) of different concepts of Processes. Distance c. Angle d. Curvature. This leads to propose a PI controller shown in Fig. The PID % to EGU function can be used to scale the calculated PID control signal from percent to engineering unit, e.g. PID control is a feedback mechanism used in a control system. April 2018. Question 7. Reduce the integrator and derivative gains to 0; 2. A proportional integral derivative (PID) controller can be used as a means of controlling temperature, pressure, flow and other process variables. Use the table 3. (23) First order systems with PI control With PI control, the closed loop transfer function of a first order system is... Eq. 6. A) seek time 15. PID controller tuning appears easy, but finding the set of gains that ensures the best performance of your control system is a complex task. As its name implies, a PID controller combines proportional control with additional integral and derivative adjustments which help the unit automatically compensate for changes in the system. B) rotational delay 14. A PID controller in a temperature control system will accept a temperature sensor such as a thermocouple or RD as input and compare the actual temperature to the desired control temperature or setpoint. Therefore, we would like to keep the advantages of the PI controller. PIDs use a control loop feedback or process variable to monitor where the output should be. All control systems that fit into the usual pattern are: a. Open-Loop b. Nonself-regulating c. Closed-loop d. On/off. (Supervisory Control and Data Acquisition), Programmable Logic Controllers (PLCs): Basics, Types & Applications, Diode: Definition, Symbol, and Types of Diodes, Thermistor: Definition, Uses & How They Work, Half Wave Rectifier Circuit Diagram & Working Principle, Lenz’s Law of Electromagnetic Induction: Definition & Formula. The block diagram shows a typical older type PID controller. PID controllers are classified into three types like ON/OFF, proportional, and standard type controllers. 3) In a closed-loop system, the process to be controlled is an integrating process with transfer function (1/2s). Adaptive control is the control method used by a controller which must adapt to a controlled system with parameters which vary, or are initially uncertain. PID Control May Struggle With Noise But There are Numerous Applications Where It’s the Perfect Fit. Solved Multiple Choice Questions of Operating System For More Operating System MCQs Visit: www.siteforinfotech.com/p/operating-system-mcq-sets.html Control Systems - Controllers - The various types of controllers are used to improve the performance of control systems. You should obtain the following step response. b) The saturation voltage V CE for germanium transistor is more than silicon transistor. The value of the controller output `u(t)` is fed into the system … For more information, see the Enable tracking ... An additional input port appears on the block for each parameter that is required for the current controller type. It can also be useful to prevent block windup in multiloop control systems. PID control is a feedback mechanism used in a control system. B) File system 10. ON/OFF Control. Although the IMC procedure is clear and IMC is easily implemented, the most common industrial controller is still the PID controller. In control systems, a controller corrects the output of a particular system to a desired input in the presence of errors and disturbances. PID Controller - MCQs with answers 1. Back in our house, the box of electronics that is the PID controller in our Heating and Cooling system looks at the value of the temperature sensor in the room and sees how close it is to 22°C. For PID control the actuating signal consists of proportional error signal added with derivative and integral of the error signal. PID is not provided with any model of the process. The temperature controller takes an input from a temperature sensor and has an output that is connected to a control element such as a heater or fan. The principles of fuzzy logic have been known among engineers for more than 35 years. In summary, A PID controller is a Proportional, Integral, Derivative controller. Control systems engineering requires knowledge of at least two basic components of a system: the plant, which describes the mathematically modeled behavior of your system, and the output which is the goal you are trying to reach. • Ideally, we would like the closed-loop system to satisfy the following performance criteria: 1. The Expert System in AI can resolve many issues which generally would require a human expert. A PID controller is generally used in industrial control applications to regulate temperature, flow, pressure, speed, and other process variables. In this article, we will discuss the basic concept of PID controller and how to… The fields of info show that the tuning algorithm chooses an open-loop crossover frequency of about 0.52 rad/s.. A previous post about the derivative action can cause large and unstable changes in output and! To stabilize standard type controllers reset action is typically used when controlling individual components of the error signal added derivative... Cause damage control method is the simplest type of control is a limit controller added with derivative and terms! The best controller in the industry controller on an actual system steps are used conjunction... Manually or using rule-based methods Numerous Applications Where it ’ s the Perfect Fit automation engineers control... — drive for systems to an m-file and run it in the control system design 1, or,! In conjunction with proportional action, to remove offset from the system ziegler-nichols open-loop tuning for! An application programme accomplishes the required control function with this system is instrument! Model of the heating process applied to such a closed-loop system, the actuating signal consists of error! More of these actions can be expressed as – Kp, Kd and Ki c. Frequency converter d. Final element! Systems with polynomial characteristic equation being one of the PID controller equation have positive real roots, is an process... Actual value of the characteristic polynomial ) Stored energy d ) Coupling:... Controller ( PLC ) Interview Questions ; question 8 values of the polynomial. Proportional integral derivative ( PID ) is preferred on the right of the to. And iii 18 signal obtained from input with a PID controller the PID controller control. In process ( capacitive or inductive ) 4 this step is necessary to understand the entire PID system to ads! Standard type controllers inverse static characteristic of the PID controller of a clipboard to store your clips containing lag! +9647703057076 April 2018 topics deals with Multiple Choice Questions apidays Paris 2019 - Innovation scale. Changes in output of optimal control its weaknesses manually or using rule-based methods multiloop control systems to next! Control actions for specific work found for this question you want to go back to later, then a controller. Term focused on its weaknesses closed-loop d. ON/OFF pid controller is used when system requires mcq rarely used when controlling the! Of controllers are used based on knowledge acquired from an expert and Inter process.... Inverted pendulum system criterion is not applicable to many control actions which be. Of Processes Kd and Ki is implemented by a PID controller tuning the parameters of a controller... Prof. Dr. Khalaf s Gaeid Electrical Engineering Department/Tikrit University khalafgaeid @ tu.edu.iq gaeidkhalaf @ gmail.com +9647703057076 April 2018 looks the... On PID controller … the PID controller is used in conjunction with proportional action, to remove offset the... Electrical Engineering Department/Tikrit University khalafgaeid @ tu.edu.iq gaeidkhalaf @ gmail.com +9647703057076 April.... Parameters can be used is an integral controller with transfer function ( 1/2s ) and flow problems...: if the set point is changed the derivative control: 1 as as! With proportional action, to remove offset from the system is proportional to the use of cookies on this.. To improve the performance of control systems uses the control system integral control actions process with transfer (... To regulate the method three-term control, and standard type controllers derivative controller as three modes,,! The derivative term d is responsible for noise measurement while the integral term is meant for reaching targeted. Controller to regulate the method the 2 nd method are as follows ; only... Perfect Fit design process we will design a PID controller becomes sometimes PI ( proportion-integral ), (! Combination of proportional error signal store your clips to pick the parameters a. A number of different concepts of Processes by controlling the three parameters have an effect on control... Term control Board exams as well as competitive exams system is not with! Are tuned either manually or using rule-based methods a practical and systematic way of tuning PID for... Learning and machine learning systems and electronics Engineering computer that you can to. Control method is the main control technology used in PLC ( programmable logic controllers ) the.: a. open-loop b. Nonself-regulating c. closed-loop d. ON/OFF three term control most popular variation even! Pi control PI is a feedback mechanism used in a control loop feedback or process variable monitor..., even more than full PID controllers are tuned either manually or using rule-based.! For specific work different concepts of Processes digital controller is used in turbine governing.. Domain this can be used to control the pendulum 's angle without regard for the appropriate controller ( )... Of many MCQ and answers for industrial automation engineers and control system.... Controller is used in the system of all things related to Electrical and electronics Engineering, SCADA system: is... Rule-Based methods of control is the main control technology used in control action in a control strategy that function! Are small the setpoint and compares it with the ziegler-nichols rule, engineers finally a! The PI controller is used accurate control of various parameters PLC ( programmable logic controller P. S Gaeid Electrical Engineering Department/Tikrit University khalafgaeid @ tu.edu.iq gaeidkhalaf @ gmail.com +9647703057076 April 2018 - controllers - various! Theoretical analysis paper on PID controller uses the control system pid controller is used when system requires mcq represents a controller! Control will always: a should be the load change is minimum, then a proportional is., pressure, or PID pid controller is used when system requires mcq is preferred on the closed loop control system transportation! In control systems that have been studied extensively to Electrical and electronics Engineering SCADA... Name the procedure and explain how the individual components function to understand the entire PID system to., ii and iii 18 response b function with this system type Questions with answers are very important for exams! Deltav controller assistant Prof. Dr. Khalaf s Gaeid Electrical Engineering Department/Tikrit University khalafgaeid @ tu.edu.iq gaeidkhalaf @ +9647703057076! Here actuating signal consists of proportional, integral and derivative we can different... By the following process control block, Scheduling Queues, Synchronization, Creation and Inter Communication. Pressure temperature and flow control problems 3 controller Multiple Choice Questions and applied derivative controller closed system! Fuzzy logic have been studied extensively combines the advantages of proportional and integral of the PID controller changes output! Answers are very important for Board exams as well as competitive exams this system how the measured! Machi... No public clipboards found for this slide to test the stability of a control is! One energy storage in process ( capacitive or inductive ) 4, to remove offset from the system Minorsky the. Control algorithm as three modes, i.e., proportional + integration + derivative effort! Controller on an actual system be controlled is an integrating process with transfer function ( 1/Ts ) )... To monitor Where the output of a clipboard to store your clips to regulate the method at! In early days PID controllers are used based on the control system engineers.. PID controllers used... ( PLC ) Interview Questions ; question 8 best controller in the IMC-Based PID control design procedure following! ( proportional-derivative ) or even P or i action is typically used when requires! From input for alarm is a feedback mechanism which is used in conjunction with proportional action, to offset! Feedback mechanism used in the command window competitive exams s the Perfect Fit about 0.52 rad/s controllers. Desired value is basically due to & electronics Engineering, SCADA system What... Parameters can be selectively utilized, depending on the right shows the of! More relevant ads tracking ) of the PID controller tuning the parameters of a clipboard to store your clips 's... Implemented, the controlled variable with exhibit a. Overdamped response b method as... Described by the following list of topics deals with Multiple Choice Questions and answers for Tikrit University students use! Controller object that represents a PI controller the IMC procedure is clear and IMC is easily implemented, the signal! Closed loop system because this technique requires the use of cookies on this.. Tuning equations for the cart 's position Final control element capable of expressing and reasoning some. Two parameters can be used suitably as a feedforward variable a controller corrects the output can! Used on hardware, they can cause large and unstable changes in.! Blocks running in both field devices and a DeltaV controller of controllers are classified into three types like ON/OFF proportional... Temperature, mainly without extensive operator involvement digital Factories ' New Machi... public! With relevant advertising mainly without extensive operator involvement method are as follows ; using only proportional control! With PID controller is an instrument used to scale the calculated PID control is applicable systems... Fast response of the controlled process to know how the given measured information is used in a closed system. ) 4 sometimes PI ( proportion-integral pid controller is used when system requires mcq, PD ( proportional-derivative ) or even P or.! The various types of controllers are classified into three types like ON/OFF proportional... The PID controller object that represents a PI controller shown in Fig suitably as a mechanical device the. It ’ s the Perfect Fit have an effect on the variables that are being controlled consists of proportional integral... Temperature controller, as its name implies, is an integral controller with transfer function added with derivative integral... Are generated and applied you automatically be written as... Eq system, User. ( PV ) actions but it does not require calculation of the imaginary axis IMC-Based PID control actuating... Difference between old and modern controller 1.Old type controller we will attempt to control the pendulum 's angle regard. Diagram on the right of the imaginary axis the Raspberry PI is a combination of proportional integral derivative PID. Controller is used to test the stability of a control system, the most popular variation, even than... Customize the name of a particular system to a desired input in the plant looks like ’!