Advantages and Disadvantages of Different Filling Media for Low-Voltage Power Capacitors

The filling media for low-voltage power capacitors primarily include dry air, inert gases (such as nitrogen), vegetable oil, mineral oil, and resin filling. Different filling media have their own advantages and disadvantages:

 

Dry Air Filling

Advantages: Simple structure, low cost, light weight, environmentally friendly and safe, with no risk of leakage.

Disadvantages: Lower voltage resistance, poor heat dissipation, suitable for small-capacity, low-voltage applications, and relatively short service life.

Inert Gas Filling (Nitrogen)

Advantages: Good fire resistance, non-flammable, excellent insulation performance, helps extend capacitor lifespan.

Disadvantages: High sealing requirements, performance affected once leakage occurs, higher cost than dry air filling, suitable for small to medium-sized capacitors.

Vegetable Oil Filling

Advantages: Environmentally friendly and non-toxic, good heat dissipation, capable of withstanding higher voltages and loads, with a relatively long lifespan.

Disadvantages: Higher cost, certain environmental temperature requirements, vegetable oil may degrade over time, unsuitable for extreme temperature environments.

Mineral Oil Filling

Advantages: Excellent insulation and heat dissipation performance, suitable for large-capacity and high-voltage capacitors.

Disadvantages: Mineral oil is somewhat toxic and polluting, poses fire hazards, poor environmental friendliness, and leakage can negatively impact the environment.

Resin Filling

Advantages: High insulation performance and mechanical strength, robust structure, capable of adapting to harsh environments, suitable for compact and small capacitor designs.

Disadvantages: Poor heat dissipation, higher cost, suitable for lightweight and small capacitors, prone to aging under high-load conditions.