Monofase Potenza Analisi
Analizza i carichi di potenza residenziali e commerciali leggeri. Calcola il profilo energetico totale oltre il semplice wattaggio.
Ingressi di Sistema
CA Monofase
Il risultato si aggiorna in tempo reale man mano che inserisci i parametri.
Le Formule del Triangolo di Potenza
La potenza CA monofase ha tre componenti — reale, reattiva e apparente — che formano il triangolo di potenza.
Potenza Reale (kW)
P = V × I × PF La potenza che svolge effettivamente il lavoro — misurata in kilowatt. È quella per cui paghi la bolletta elettrica.
Potenza Reattiva (kVAR)
Q = V × I × sin(θ) Potenza immagazzinata e rilasciata da carichi induttivi e capacitivi. Causa corrente senza svolgere lavoro utile, aumentando le perdite nei cavi.
Potenza Apparente (kVA)
S = V × I = √(P² + Q²) La potenza totale che l'alimentazione deve fornire — la somma vettoriale della potenza reale e reattiva. Usata per dimensionare generatori e trasformatori.
Understanding Single-Phase AC Power
Single-phase AC power is the standard supply for residential buildings and light commercial facilities. Unlike DC, AC voltage reverses direction periodically (50 or 60 times per second), which enables efficient voltage transformation but introduces the concept of power factor — the relationship between the voltage and current waveforms.
The Power Triangle
Real power (kW), reactive power (kVAR), and apparent power (kVA) form a right triangle. The angle θ between the apparent and real power vectors is the phase angle — and the cosine of this angle is the power factor. A PF of 1.0 means the triangle collapses to a straight line: all apparent power is real power.
What Causes Low Power Factor?
- Induction Motors: The most common cause. Motors use reactive power to build rotating magnetic fields. Lightly loaded motors have worse PF than fully loaded ones.
- Transformers at Light Load: The magnetizing current drawn by transformer cores is largely reactive.
- Fluorescent Lighting (older ballasts): Magnetic ballasts introduce significant reactive current. Electronic ballasts largely solve this.
- Variable Speed Drives: Can improve motor PF but introduce harmonic distortion which has its own effects on the supply.
Power Factor Correction
Low power factor can be corrected by adding capacitor banks in parallel with inductive loads. Capacitors supply reactive power locally, reducing the reactive current that must flow from the utility. This reduces cable losses, improves voltage regulation, and avoids utility penalties for industrial customers with PF below 0.9.