Contents
Trigonometric identites Frequently used in complex power calculations
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Instantaneous Power |
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Average , Maximum and Minimum power in terms of power factor (PF) |
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Complex Power |
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1. Apparent Power is the magnitude of the complex power.
2. Average/Real Power and Reactive Power is the real part and imaginary part of the complex power respectively.
3. Unit of reactive power is VARS |
Reactive Power (VARS) |
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Average Power/Real Power
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Complex Power |
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1.
Apparent Power =
2. The unit of apparent power is VA
3. Apparent power is the magnitude of the complex power. |
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1.
Complex Power 2.
Real Power 3.
Reactive Power 4.
Apparent Power |
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Average value of |
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Average value of |
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Inductance of a coil with N turns,
cross section area A, length L and core permeability |
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Voltage induced across an inductor |
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Voltage induced across a coil (w.r.t
flux linkage |
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Flux linkage |
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Energy stored in an inductor |
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Magnetic equivalent of electric current |
Source of EMF is battery |
Source of MMF is current coil |
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A current entering the dotted terminal of one coil produces voltage with a positive voltage reference at the dotted terminal of the second coil. |
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A current entering the dotted terminal of one coil produces voltage with a positive voltage reference at the dotted terminal of the second coil. |
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Voltages and currents in terms of phasors |
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Coefficient of mutual coupling |
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Dot convention and current / voltage polarity reference |
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Reflection of secondary into primary
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Reflection of primary into secondary
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Current and flux direction using right hand rule |
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LENZ’S LAW
The direction of the induced voltage( in other words the current direction)will be such that it will oppose the change in the flux |
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General Transformer Equation |
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Impedance Matching |
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If the transformer is acting as an impedance matching device than
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Bridge circuit can be used to determine the value of an unknown resistance.
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The
bridge is balanced if
When the bridge is balanced then
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