What Causes Power Capacitor Failure in Industrial Systems?

A power capacitor can operate for many years when properly selected and installed. However, several factors can shorten its service life.

Excessive Temperature

Heat is one of the major causes of capacitor aging.

Poor cabinet ventilation, high ambient temperature and heat from neighboring equipment can increase internal stress.

Harmonic Current

Harmonics can increase capacitor current and temperature.

Facilities with many nonlinear loads therefore require special attention to harmonic conditions.

Overvoltage

Continuous operation above the intended voltage level places additional stress on the dielectric system.

Excessive Switching

Frequent switching creates repeated electrical stress.

The switching device must therefore be appropriate for capacitor loads.

Incorrect Capacitance

An incorrectly selected capacitor bank may cause overcompensation or poor system performance.

Manufacturing Quality

Film quality, winding, impregnation and safety mechanisms all influence long-term reliability.

Geyue Electric's BSMJ and BSMJ(Y) series products are developed for low-voltage reactive power compensation applications, with different configurations for different system requirements.

Conclusion

Most capacitor failures are not caused by a single factor. The electrical environment, installation conditions and product construction should be evaluated together.