How to find the crossing point of root locus in imaginary axis.

How to find the crossing point of root locus in imaginary axis.
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1 Answer

Answer :

Method (i) by Routh Hurwitz criterion
Method (ii) by letting s=jw in the characteristics equation.
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Related questions

How will you find root locus on real axis.

Description : How will you find root locus on real axis.

Last Answer : To find the root locus on real axis, choose a test point on real axis. If the total number of poles and zeros on the real axis to the right of this rest point is odd number then the rest point lies on the root locus. If it is even then the test point does not lie on the root locus.

What are the main significances of root locus?

Description : What are the main significances of root locus?

Last Answer : i. The main root locus technique is used for stability analysis. ii. Using root locus technique the range of values of K, for as table system can be determined

In root locus plot, a point on the real axis lies on the locus, if the number of open loop poles plus zeros on

Description : In root locus plot, a point on the real axis lies on the locus, if the number of open loop poles plus zeros on real axis to the a) left of the point is odd b) left of the point is even . c) right of the pointis odd d) right of the point is even

Last Answer : In root locus plot, a point on the real axis lies on the locus, if the number of open loop poles plus zeros on real axis to the right of the pointis odd

What are root loci?

Description : What are root loci?

Last Answer : The path taken by the roots of the open loop transfer function when the loop gain is varied from 0 to α is called root loci.

The normal at a point `P` on the ellipse `x^2+4y^2=16` meets the x-axis at `Qdot` If `M` is the midpoint of the line segment `P Q ,` then the locus of

Description : The normal at a point `P` on the ellipse `x^2+4y^2=16` meets the x-axis at `Qdot` If `M` is the midpoint of the line segment `P Q ,` then the locus of

Last Answer : The normal at a point `P` on the ellipse `x^2+4y^2=16` meets the x-axis at `Qdot` If `M` is ... (pm2sqrt3,pmsqrt1/7)` D. `(pm2sqrt3,pm(4sqrt(3))/4)`

How the break away point & break in point to determine

Description : How the break away point & break in point to determine

Last Answer : To find the break away or break in points, form an equation for K from the characteristics equation and differentiated the equation the equation of K with respect to s. Then find the roots of equation ... or break-in points provided for this value of root the gain K should be positive and real.

What is break in point?

Description : What is break in point?

Last Answer : At break in point the root locus enters from the real axis to from the complex plane.

What is break away point?

Description : What is break away point?

Last Answer : At break away point the root locus breaks from the real axis to enter into the complex plane.

Whether a given point in the S-plane lies on the Root Locus of a system can be determined by

Description : Whether a given point in the S-plane lies on the Root Locus of a system can be determined by (A) Magnitude criterion (B) Angle Criterion (C) Both Magnitude and Angle Criteria (D) Break-in and Break-away Criteria

Last Answer : Whether a given point in the S-plane lies on the Root Locus of a system can be determined by Angle Criterion

The locus of the moment of inertia about inclined axes to the principal axis, is (A) Straight line (B) Parabola (C) Circle (D) Ellipse

Description : The locus of the moment of inertia about inclined axes to the principal axis, is  (A) Straight line  (B) Parabola  (C) Circle  (D) Ellipse

Last Answer : (D) Ellipse

Frequency Domain Analysis in Control System

Description : Frequency Domain Analysis in Control System

Last Answer : Frequency Response: The Frequency Response of the system is the steady state response of the system obtained as the output when a sinusoidal input signal is given to the system. For determining the ... of the system, adjust the gain of the control system and helps in designing the control system.

Advantages of Frequency Domain Analysis

Description : Advantages of Frequency Domain Analysis

Last Answer : Advantages of Frequency Domain Analysis Frequency Response Analysis: In frequency response analysis the input to the control system is fed with a sinusoidal signal with different frequencies. The output ... system Frequency domain analysis can also be carried out for the non linear control systems.

PI Controllers in Process System

Description : PI Controllers in Process System

Last Answer : PI controllers are used in many industrial control applications. The main purpose of using Proportional and Integral (PI) in process system is to improve the steady state accuracy of the ... requires higher values of the proportional and integral gains compared to gains required in PI controllers

What is Zero of the system?

Description : What is Zero of the system?

Last Answer : Zero of a function F(s) is a value at which the function F(s) becomes zero, where F(s) is a function of complex variable s.

What is Pole of the system?

Description : What is Pole of the system?

Last Answer : Pole of a function F(s) is the value at which the function F(s) becomes infinite, where F(s) is a function of the complex variable s.

What are Test signals and their significance?

Description : What are Test signals and their significance?

Last Answer : The knowledge of the input signal is required to predict the response of the system. In most of the systems input signals are not known ahead of the time and it is also difficult to ... the control system. The commonly used test signals are impulse, ramp, step signals and sinusoidal signals.

How Time response of the system is divided?

Description : How Time response of the system is divided?

Last Answer : Time response of the system consists of two parts: 1.Transient state response 2. Steady state response. Transient response of the system explains about the response of the system when the input ... other. Steady state response of the system shows the response as the time t, approaches infinity

What is Time response of the control system?

Description : What is Time response of the control system?

Last Answer : Time response of the control system is defined as the output of the closed loop system as a function of time. Time response of the system can be obtained by solving the differential equations governing the system or time response of the system can also be obtained by transfer function of the system.

What is Order of the system?

Description : What is Order of the system?

Last Answer : Order of the system is defined as the order of the differential equation governing the system. Order of the system can be determined from the transfer function of the system. Also the order of ... function. For nth order system for a particular transfer function contains 'n' number of poles.

Explain Mechanical Translational System?

Description : Explain Mechanical Translational System?

Last Answer : Model of mechanical translational system can be obtained by using three basic elements Mass, Spring and Dash-pot. Weight the mechanical system is represented by mass and is assumed to be ... represented by the spring Friction existing in a mechanical system can be represented by dash-pot.

What is mathematical model of a control system?

Description : What is mathematical model of a control system?

Last Answer : Control system is a collection of physical elements connected together to serve an objective. The output and input relations of various physical system are governed by differential equations. ... the system can be studied by solving the differential equations for various input conditions.

What are the basic properties of Signal Flow Graph?

Description : What are the basic properties of Signal Flow Graph?

Last Answer : The basic properties of the signal flow graph are: Signal Flow Graphs are applicable to linear systems It consists of nodes and branches. A node is a point representing a variable or signal. A ... the gain of the branch The algebraic equations must be in the form of cause and effect relationship

What is S-domain and its significance?

Description : What is S-domain and its significance?

Last Answer : By taking Laplace transform for differential equation in the time domain equations in S-domain can be obtained. L{F(t)}=F(s) S domain is used for solving the time domain differential equations easily by applying the Laplace for the differential equations.

What is Signal Flow Graph?

Description : What is Signal Flow Graph?

Last Answer : A Signal Flow Graph is a diagram that represents a set of simultaneous linear algebraic equations. By taking Laplace transform the time domain differential equations governing a control system can be ... s-domain. The signal Flow graph of the system can be constructed using these equations.

Where Servomechanism is used?

Description : Where Servomechanism is used?

Last Answer : Servomechanism is used in control system where the output is pertained to vary the mechanical position of a device. Servo Mechanism is widely used in Governor value position control mechanism ... controls using power Thyristors. Servomechanism is also widely used in the robotic hand movements.

What is the basic rule for Block Diagram Reduction Technique?

Description : What is the basic rule for Block Diagram Reduction Technique?

Last Answer : The rules of the Block Diagram reduction Techniques are designed in such a manner that any modifications made in the diagram will not alter the input and output relation of the system

What is Time Invariant system?

Description : What is Time Invariant system?

Last Answer : Time Invariant System is one in which the input and output characteristics of the system does not change with time.

Define Transfer Function?

Description : Define Transfer Function?

Last Answer : Transfer Function of a control system is defined as: i) Ratio of Laplace transform of Output to the Laplace transform of the Input with zero initial conditions ii) Transfer function is defined as the Laplace transform of Impulse response of the system with zero initial conditions

What are the basic components of the feedback control system?

Description : What are the basic components of the feedback control system?

Last Answer : Basic components of the feedback control system are process system (open loop system), feedback path element, error detector, and controller.

What are the Characteristics of Negative Feedback?

Description : What are the Characteristics of Negative Feedback?

Last Answer : Negative Feedback in a Control System has following Characteristics Reduction in the gain at the expense of better stability of the system Rejection of disturbance signals in the system Low Sensitivity to parameter variations Accuracy in tracking the steady state value

What is the effect of positive feedback on stability of the system?

Description : What is the effect of positive feedback on stability of the system?

Last Answer : Positive feedback is not used generally in the control system because it increases the error signal and drives the system to instability. But positive feedbacks are used in minor loop control systems to amplify certain internal signals and parameters

Why Negative Feedback is preferred in the Control System?

Description : Why Negative Feedback is preferred in the Control System?

Last Answer : The role of Feedback in control system is to take the sampled output back to the input and compare output signal with input signal for error ( deviation from the desired result). ... and is less sensitive to the parameter variations. Hence in control systems negative feedback is considered.

What is a feedback in Control System?

Description : What is a feedback in Control System?

Last Answer : The Feedback in Control System in one in which the output is sampled and proportional signal is fed back to the input for automatic correction of the error ( any change in desired output) for futher processing to get back the desired output.

What are different types of Control Systems?

Description : What are different types of Control Systems?

Last Answer : Two major types of Control Systems are 1) Open loop Control System 2) Closed Loop Control Systems Open loop Control Systems: The Open loop Control System is one in which the Output Quantity has ... quantity to the input quantity for the correction so as to maintain the desired output of the system.

What is Control System?

Description : What is Control System?

Last Answer : In a System the output and inputs are interrelated in such a manner that the output quantity or variable is controlled by input quantity, then such a system is called Control System. The ... is called controlled variable or response and the input quantity is called command signal or excitation.

What is a System?

Description : What is a System?

Last Answer : When a number of elements or components are connected in a sequence to perform a specific function, the group of elements that all constitute a System

Closed loop and Open loop Control System Advantages and Disadvantages

Description : Closed loop and Open loop Control System Advantages and Disadvantages

Last Answer : Open Loop Control System: Control System in which output quantity has no effect on the input quantity is called Open Loop Control System. Open Loop Control System has no facility to correct automatically the ... in the closed loop system and more care is needed to design a stable closed loop system

Phase Margin?

Description : Phase Margin?

Last Answer : Answer: The phase margin is the amount of additional phase lag at the gain cross over frequency required to bring the system to the verge of instability.

What is Gain Margin?

Description : What is Gain Margin?

Last Answer : Answer: The Gain Margin is defined as the reciprocal of the magnitude of open loop transfer function at phase cross over frequency. The gain margin indicates the amount by which the gain of the system can be increased without affecting the stability of the system

What is Phase cross over frequency?

Description : What is Phase cross over frequency?

Last Answer : Answer: The frequency at which the phase of the open loop transfer function is 180o is called the phase cross over frequency.

What is Cut-off rate?

Description : What is Cut-off rate?

Last Answer : Answer: The slope of the log-magnitude curve near the cut-off frequency is called the cut-off rate. The cut-off rate indicates the ability of the system to distinguish between the signal and the noise

What is Resonant Frequency?

Description : What is Resonant Frequency?

Last Answer : Answer: The frequency at which resonant peak occurs is called the resonant frequency. Resonance frequency explains about the speed of the transient response.

What is Resonant peak?

Description : What is Resonant peak?

Last Answer : Answer: Resonant peak is defined as the maximum value of the closed loop transfer function.A large resonant peak corresponds to large overshoot in the transient respose

Distributed Control System (DCS) in Power Plant

Description : Distributed Control System (DCS) in Power Plant

Last Answer : Usage of Single Computer for control of all the process variables of plant would result in the loss of control action in the plant if failure occurs to the master single computer. Also, ... control loop This type of distribution results in increase in speed and reliability of the control system.

Why are two plugs provided on a D.P transmitter?

Description : Why are two plugs provided on a D.P transmitter? 

Last Answer : 1.The top plug is a vent plug for venting the air entrapped inside the cell. 2.The bottom plug is a drain plug for draining the liquid accumulated inside the cell.  

What is positive Displacement meters ?

Description : What is positive Displacement meters ? 

Last Answer : principle: The principle of measurement is that as the liquid flows through the meter it moves a measuring element which seals off the measuring chamber into a series of measuring compartments each holding a definite ... type. 5. Sliding vane type. 6. Rotating vane type. 7. Oval Gear type.  

How would you choose differential range ?

Description : How would you choose differential range ?

Last Answer : The most common diff. range for liquid measurement is 0-100" H2O. This range is high enough to minimize the errors caused by unequal heads in the seal chambers, differences in temps. of load lines etc. ... up to 400" and a decrease down up to 20" by merely changing range tubes or range adjustments. 

What is Reynolds number ?

Description : What is Reynolds number ?

Last Answer : Dynamic similarity implies a correspondence of fluid forces in two systems. In general situation there are many classes of forces that influence the behavior of fluids. Some of these are ... , many of the deviation from the theoretical equations are called Reynaldo number effects.   

Where is a quadrant orifice used ?

Description : Where is a quadrant orifice used ? 

Last Answer : If the fluid is viscous and the operating Reynolds number is low quadrant orifice is preferred  

Explain the working of a target meter.

Description : Explain the working of a target meter.

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