Yes, Norton’s Theorem is applicable for AC circuits as well as DC circuits. The theorem, which states that any linear electrical network with multiple sources and resistances can be simplified to a single current source in parallel with a single resistor, is valid regardless of whether the sources are AC or DC.
However, when dealing with AC circuits, there are a few additional considerations:
1. **Impedance vs. Resistance**: In AC circuits, instead of resistances, you will be working with impedances. Impedance (Z) includes both resistance (R) and reactance (X) and is generally represented as a complex number \( Z = R + jX \), where \( j \) is the imaginary unit.
2. **Phasors and Complex Analysis**: AC circuit analysis often involves phasors and complex numbers. When applying Norton’s Theorem, you need to account for the phase relationships between voltage and current. This means you’ll use complex impedance and perform calculations in the frequency domain.
3. **Frequency Dependence**: The impedance of reactive components (capacitors and inductors) depends on the frequency of the AC signal. This frequency dependence must be considered when finding the Norton equivalent impedance.
### Applying Norton’s Theorem to AC Circuits
1. **Find the Norton Current**: Determine the current through a hypothetical short circuit placed across the terminals where you want to find the Norton equivalent. This involves calculating the response of the circuit to a short circuit in the AC domain.
2. **Find the Norton Impedance**: Calculate the impedance seen from the terminals with all independent sources turned off (replaced by their internal impedances—voltage sources by short circuits and current sources by open circuits). This impedance will be a complex quantity.
3. **Construct the Norton Equivalent Circuit**: The Norton equivalent circuit consists of a current source equal to the Norton current and an impedance in parallel equal to the Norton impedance.
By following these steps, you can analyze and simplify AC circuits using Norton’s Theorem just as you would with DC circuits.