Question 4. a) State what are the through- and across-variables of an electrical system? [4 marks] b) Show through equations and sketches how the capacitor element of an electrical system can be modelled mathematically to derive its transfer function. [5 marks] c) Show how the series resistor-capacitor (RC) lumped element electrical system is modelled, by sketching the circuit and deriving the constitutive equation and transfer function relating output voltage (across the capacitor) to input voltage. [10 marks] Question 4 a) For an electrical system, the through-variable is the current i, while the across-variable is the potential or voltage difference VAB across an element/system. b) Sketch capacitor symbol; capacitance C Potential difference v related to charge Q and C by v=Q/C Since current i=dQ/dt, Q = integral of i.dt, so v=1/C(integral of i.dt) or i = Cdv/dt Show Laplace transform (this is analogous to the mechanical model for a spring element) c) Sketch of resistor and capacitor in series with a voltage source. The directions of v_r and v_c polarity should be indicated. Applying Kirchoff's Voltage Law (KVL), v_i=v_r+v_c (where v_c is the output voltage in this case) Since v=iR and i=C(dv_c/dt) we get v_i = RC(dv_c/dt) + v_c Develop Laplace form of this and show time constant T=RC

Introductory Circuit Analysis (13th Edition)
13th Edition
ISBN:9780133923605
Author:Robert L. Boylestad
Publisher:Robert L. Boylestad
Chapter1: Introduction
Section: Chapter Questions
Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...
icon
Related questions
Question

Please answer part b and c with diagrams. 
The GENERAL solution is provided below. 

Question 4.
a) State what are the through- and across-variables of an electrical system?
[4 marks]
b) Show through equations and sketches how the capacitor element of an electrical system can be
modelled mathematically to derive its transfer function.
[5 marks]
c) Show how the series resistor-capacitor (RC) lumped element electrical system is modelled, by
sketching the circuit and deriving the constitutive equation and transfer function relating output
voltage (across the capacitor) to input voltage.
[10 marks]
Transcribed Image Text:Question 4. a) State what are the through- and across-variables of an electrical system? [4 marks] b) Show through equations and sketches how the capacitor element of an electrical system can be modelled mathematically to derive its transfer function. [5 marks] c) Show how the series resistor-capacitor (RC) lumped element electrical system is modelled, by sketching the circuit and deriving the constitutive equation and transfer function relating output voltage (across the capacitor) to input voltage. [10 marks]
Question 4
a)
For an electrical system, the through-variable is the current i, while the across-variable is the
potential or voltage difference VAB across an element/system.
b)
Sketch capacitor symbol; capacitance C
Potential difference v related to charge Q and C by v=Q/C
Since current i=dQ/dt, Q = integral of i.dt, so v=1/C(integral of i.dt) or i = Cdv/dt
Show Laplace transform (this is analogous to the mechanical model for a spring element)
c)
Sketch of resistor and capacitor in series with a voltage source. The directions of v_r and v_c polarity
should be indicated.
Applying Kirchoff's Voltage Law (KVL),
v_i=v_r+v_c (where v_c is the output voltage in this case)
Since v=iR and i=C(dv_c/dt) we get
v_i = RC(dv_c/dt) + v_c
Develop Laplace form of this and show time constant T=RC
Transcribed Image Text:Question 4 a) For an electrical system, the through-variable is the current i, while the across-variable is the potential or voltage difference VAB across an element/system. b) Sketch capacitor symbol; capacitance C Potential difference v related to charge Q and C by v=Q/C Since current i=dQ/dt, Q = integral of i.dt, so v=1/C(integral of i.dt) or i = Cdv/dt Show Laplace transform (this is analogous to the mechanical model for a spring element) c) Sketch of resistor and capacitor in series with a voltage source. The directions of v_r and v_c polarity should be indicated. Applying Kirchoff's Voltage Law (KVL), v_i=v_r+v_c (where v_c is the output voltage in this case) Since v=iR and i=C(dv_c/dt) we get v_i = RC(dv_c/dt) + v_c Develop Laplace form of this and show time constant T=RC
Expert Solution
steps

Step by step

Solved in 2 steps with 1 images

Blurred answer
Similar questions
Recommended textbooks for you
Introductory Circuit Analysis (13th Edition)
Introductory Circuit Analysis (13th Edition)
Electrical Engineering
ISBN:
9780133923605
Author:
Robert L. Boylestad
Publisher:
PEARSON
Delmar's Standard Textbook Of Electricity
Delmar's Standard Textbook Of Electricity
Electrical Engineering
ISBN:
9781337900348
Author:
Stephen L. Herman
Publisher:
Cengage Learning
Programmable Logic Controllers
Programmable Logic Controllers
Electrical Engineering
ISBN:
9780073373843
Author:
Frank D. Petruzella
Publisher:
McGraw-Hill Education
Fundamentals of Electric Circuits
Fundamentals of Electric Circuits
Electrical Engineering
ISBN:
9780078028229
Author:
Charles K Alexander, Matthew Sadiku
Publisher:
McGraw-Hill Education
Electric Circuits. (11th Edition)
Electric Circuits. (11th Edition)
Electrical Engineering
ISBN:
9780134746968
Author:
James W. Nilsson, Susan Riedel
Publisher:
PEARSON
Engineering Electromagnetics
Engineering Electromagnetics
Electrical Engineering
ISBN:
9780078028151
Author:
Hayt, William H. (william Hart), Jr, BUCK, John A.
Publisher:
Mcgraw-hill Education,