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E E 2315. Lecture 15 Phasor Circuit Analysis, Effective Value and Complex Power: Watts, VAR’s and Volt-Amperes. Effective Value of a Sinusoid (1/2). Average Power:. Effective Value of a Sinusoid (2/2). In our example:. Also:. The effective value is also called the Root Mean
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E E 2315 Lecture 15 Phasor Circuit Analysis, Effective Value and Complex Power: Watts, VAR’s and Volt-Amperes
Effective Value of a Sinusoid (1/2) Average Power:
Effective Value of a Sinusoid (2/2) In our example: Also: The effective value is also called the Root Mean Square value or rms value.
R-C Circuit Example (1/6) Capacitive Reactance
R-C Circuit Example (2/6) Using rms phasor for voltage source.
R-C Circuit Example (3/6) Calculate Real Power: And Reactive Power: Apparent power is the product of voltage and current of the source. Also:
R-C Circuit Example (4/6) Power Factor is the ratio of real power to apparent power: Power Factor is also the Cosine of the angle between the load voltage and the load current: If the load current leads the load voltage, the power factor is leading; if it lags the load voltage, the power factor is lagging.
R-C Circuit Example (5/6) Phasor Diagram of Voltage and Current Current leads voltage.
R-C Circuit Example (6/6) The Power Triangle showing leading power factor.
Calculating Complex Power (2/2) From now on, we use the above method to calculate complex power.
Lagging Power Factor Example (2/4) Calculate complex power directly:
Lagging Power Factor Example (3/4) Power Factor: Power Factor is Lagging Phasor Diagram of Voltage and Current
Lagging Power Factor Example (4/4) Power Triangle for lagging Power Factor
Phasor Power Example (3/4) Capacitor VAR’s: