AC 回路の電源変換

Source transformation converts a voltage source in series with an impedance into a current source in parallel with the same impedance, or vice versa. This technique simplifies circuit analysis in the frequency domain by allowing flexible source representation. The transformation maintains equivalent circuit behavior while enabling easier application of circuit analysis methods.

To convert a current source to a voltage source, multiply the source current by the parallel impedance to obtain the source voltage using Ohm's law. Express this voltage value in phasor form for AC circuit analysis. The resulting voltage source is then placed in series with the same impedance that was previously in parallel.

Source transformation simplifies complex circuits by converting between source types, reducing the circuit to more manageable forms. By repeatedly applying transformations and combining impedances, you can systematically reduce the circuit until voltage division rule can determine the desired voltage drop across any branch efficiently.

Impedance remains constant during source transformation—it stays the same whether the source is voltage or current type. The impedance value is essential for calculating the equivalent source using Ohm's law and for determining series or parallel impedance combinations throughout the transformation process.

After transforming sources and combining impedances, voltage division rule calculates the voltage drop across a specific branch. This rule states that the voltage across an impedance equals the total voltage multiplied by the ratio of that impedance to the total series impedance in the circuit.

Source current and source voltage are related through impedance via Ohm's law: source voltage equals source current multiplied by impedance. When transforming between current and voltage sources, this relationship must be maintained to ensure the transformed circuit remains electrically equivalent to the original circuit.

Yes, source transformation can be applied repeatedly throughout circuit analysis. Multiple transformations allow systematic simplification of complex circuits with mixed sources and impedances. Each transformation maintains circuit equivalence, enabling progressive reduction until the desired voltage or current can be calculated using phasor relationships for circuit elements.