OPERATION OF TWO PORT NETWORKS

Circuit Theory Laws and the Operation of Two Port Networks



Circuit Theory Laws and the Operation of Two Port Networks

 Introduction and Definitions

Generally, a network has two pairs of terminals; one pair is denoted as the input terminals, and the other as the output terminals. Such networks are very useful in the design of electronic systems, transmission and distribution systems, automatic control systems, communications systems, and others where electric energy or a signal enters the input terminals, it is modified by the network, and it exits through the output terminals (Nilsson, 2007, 112).

Discussion

Specification:

(a)

Rt = 130(

For the circuit calculate the current through the meter and hence the voltage across the meter: if the meter has the following resistances: 100(, 1k( and 10k(

Set up the circuit on Multisim and measure the currents. Comment on your results and write a brief paragraph on the techniques used to calculate your answers and any differences between calculated and measured values.

Answer

100(, Rt = 130(

To calculate the circuit power...To calculate the circuit resistance... The formula is R = V / AR = V2 / W or,R = W / I2Enter any two factors of V, I, and R  Voltage      Current      ResistanceCurrent: 76.92307692307692 (

1k(, Rt = 130(

To calculate the circuit power...To calculate the circuit resistance... The formula is R = V / AR = V2 / W or,R = W / I2Enter any two factors of V, I, and R  Voltage      Current      ResistanceCurrent: 7692.307692307692 (

10k(, Rt = 130(

To calculate the circuit power...To calculate the circuit resistance... The formula is R = V / AR = V2 / W or,R = W / I2Enter any two factors of V, I, and R  Voltage      Current      ResistanceCurrent: 769230.7692307692 (

(b) A mains drill has an inductance of 145 mH and a resistance of 45(. How much power would it consume from the mains? Does it require PF correction? If it does how can this be achieved. What are the new power and the change in current?

Answer: To calculate the circuit power...To calculate the circuit resistance... The formula is R = V / AR = V2 / W or,R = W / I2Enter any two factors of V, I, and R  Voltage      Current      ResistanceCurrent: 161.73076923076923 (

Analysis

The Ohm's Law Triangle shown above is a memory aid used to help remember the formula required to solve for an unknown circuit value.

Simply cover the unknown quantity (the value that you are trying to find) and the remaining values and their relationship to each other will indicate mathematical operation required to solve for the unknown quantity.

For example, to solve for voltage (E) cover the E, the remaining values I and R are side-by-side indicating multiplication. If solving for current (I), cover the I and the remaining value E is over R indicating division.

Power, the rate of doing work, in an electrical circuit is equal to the applied voltage multiplied by current. The basic unit of electrical power, the watt, is named after James Watt (1736 - 1819) in honor of his work contributing to the development of the steam engine. One watt is equal to one volt multiplied by ...