Theory of Electricity
Review these from S1.
- Charge
- Potential difference
- Current
- Power
- Kirchoff’s laws
- Circuit elements
- Resistors
- Capacitors - Voltage through a capacitor cannot change instantaneously
- Inductors- Current through an inductor cannot change instantaneously
- Impedance & Admittance
- Active elements
Recommended textbooks
- Charles K., Alexander, M. N. O. S., Fundamentals of Electric Circuits 5th Edition, McGraw Hill, NewYork, NY, USA, 2013, ISBN 978-0-07-338057-5
- Hambley, A. R., Electrical Engineering Principles and Applications 5th Edition, Pearson Education, Inc., Upper Saddle River, New Jersey,USA, 2011, ISBN-13: 978-0-13-213006-6.
- Nahvi M., Edminister J.A., Electric Circuits 4th Edition, Schaum’s Outline Series, McGraw Hill, New York, NY, USA 2003, DOI: 10.1036/0071425829.
- Theory and Problems of Basic Electrical Engineering, D P Kothari, I J Kothari, Prentice Hall of India, New Delhi
- Electrical Engineering Fundamentals, Vincent Del Toro, Prentice Hall of India, New Delhi
Types of active elements
| Source | Notation |
|---|---|
| Current Source | |
| DC Voltage Source | |
| AC Voltage Source |
Independent source
The terminal voltage or current depends only on the loading & internal source quantity.
Dependent source
The terminal voltage or current depends on another circuit quantity such as a voltage or current. Categorized into 4.
- Voltage-controlled voltage source
- Voltage-controlled current source
- Current-controlled voltage source
- Current-controlled current source
Dependent sources are denoted with the relationship with another independent source.
Waveform errors
DC Offset
A DC voltage superimposed on a AC waveform shifts it up or down. Causes unwanted clipping of the AC voltage when amplification. Causes the waveform to have reduced dynamic range, reduced headroom, increases noise when amplified and causes problems with DC-coupled circuits.
Moving iron instrument
Can be identified by AC symbol. Measures the rms value of the signal.
Moving coil instrument
Can be identified by DC symbol. Measures the average value of the signal.
Moving coil rectifier instrument
Can be identified by diode symbol. Measures the rms value of the rectified signal. Full wave rectifier bridge of 4 diodes is used. Assuming the current is sinusoidal, the scale of this instrument must be marked in terms of 1.11 timies the current.
Special functions
Unit step function
Unit impulse function
Properties
Area under the curve is