22/03/2026
Fundamentos de análisis CA de circuitos RLC.
A series RLC circuit contains a resistor (R), inductor (L), and capacitor (C) connected in a single path, so the same current flows through all components. However, each element responds differently to AC signals.
The resistor behaves simply: voltage across it (VR) is in phase with current. This means both rise and fall together. The inductor stores energy in a magnetic field, causing its voltage (VL) to lead the current by 90°. The capacitor stores energy in an electric field, and its voltage (VC) lags the current by 90°.
The opposition to AC is called impedance (Z), not just resistance. It combines resistance (R) and reactance. Inductive reactance is XL = ωL, and capacitive reactance is XC = 1/(ωC). The total impedance is Z = √(R² + (XL − XC)²), and current is given by I = V/Z.
The phase angle between voltage and current depends on (XL − XC). If XL > XC, the circuit is inductive and current lags. If XC > XL, it is capacitive and current leads.
At resonance, XL equals XC, so they cancel each other. The circuit behaves like a pure resistor, impedance becomes minimum (Z = R), and current is maximum. Also, voltage and current are perfectly in phase (phase angle = 0°).
This concept is widely used in filters, tuning circuits, and frequency selection applications.
