What is Capacitor?

Master Electrician
07/11/2024 08:55:02


What is Electrical  Capacitor?


Capacitor definition


Capacitor is the ability of capacitor to store charge per unit voltage, which is mainly used in power supply filtering, signal filtering, signal coupling, resonance, filtering, compensation, charge and discharge, energy storage, DC isolation and other circuits. The unit of capacitor is farad, labeled F, and the symbol of capacitor is C.


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Computational formula 


  • Equation of definition :



C=Q/U


  • Capacitor potential energy calculation formula :


E=C*(U^2)/2=QU/2=(Q^2)/2C


  • Multi-capacitor parallel calculation formula :


C=C1+C2+C3+…+Cn


  • Multi-capacitor series calculation formula :



1/C=1/C1+1/C2+…+1/Cn



  • Three capacitor series :



C=(C1*C2*C3)/(C1*C2+C2*C3+C1*C3)



Action of capacitance


  • By-pass

  • Decoupling

  • Filtering

  • Stored energy



Factors affecting capacitance


  • The capacitance depends on the plate area

  • Distance between plates

  • Dielectric constant of a dielectric material


How a multimeter detects capacitance


  • Direct detection with capacitor file

  • Detect with resistance

  • Detect with voltage file


Types of capacitors


  • Non-polar variable capacitor

  • Non-polar fixed capacitance

  • Polar capacitance



Development direction


  • Miniaturization

  • Low pressure high capacity

  • Super small and thin





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