Polypropylene Film Capacitor Energy Conversion and Transfer

In fact, the definition of polypropylene film capacitors: "containers" that store charge or store electric field energy. Capacitance C = unit of capacitance: F, μF, nF, pF. 1F=106μF=109nF=1012pF1μF=103nF=106pF1nF=Capacitor capacity of 103pF Marking method: Straight labeling method such as: 1u0, 100n, 1n0 Numerical method such as: 105, 104, 102 Equivalent circuit of actual capacitor Where: RI—capacitor insulation Resistor LS—Capacitor's own inductance CS—Equivalent series capacitance RS—Equivalent series resistance of loss

The energy consumed by heat generation per unit time is called the loss of the capacitor. Generally, the loss tangent is expressed as: tgδ=active power/reactive power. Losses are mainly: Conductive losses due to dielectric loss dielectric leakage current. Polarization Loss Caused by Slow Polarization of Media Ionization Loss Metal Loss (leads, plates, contact between lead and plate) Polypropylene film Capacitor loss tangent Common test method: 20°C, 1KHz Polyester (CL) ≤ 0.01 Polypropylene (CBB) ≤ 0.001 Since the dielectric polarity is different, the loss tangent of a polypropylene film capacitor is much smaller than that of a polyester film capacitor, and the loss frequency characteristics particularly when used at high frequencies are much better.

The ideal capacitor can store all the energy obtained from the power supply in the capacitor. In practice, the capacitor consumes a certain amount of energy in the circuit. That is, a part of the electrical energy stored in the capacitor is converted into heat energy. Thermal energy heats the capacitor on the one hand and raises the temperature. On the other hand, the surface of the polypropylene film capacitor is emitted into the surrounding environment.