What factors affect the service life of self-healing low-voltage parallel capacitors?

The actual service life of self-healing low-voltage parallel capacitors often differs from the theoretical value. This difference is caused by the combined effect of various external and internal factors. Understanding these influencing factors can help users optimize the operating conditions and maximize the service life of the equipment.

I. Impact of Electrical Operating Parameters

1. Voltage stress effect:

Long-term overvoltage accelerates the aging of the medium.
Voltage fluctuations lead to repeated stress changes.
Harmonic voltage leads to equivalent overload.

2. Current Load Characteristics:

The impact current generated by frequent switching operations
Additional heat generated by harmonic currents
Damage to the metallization layer caused by overcurrent

II. The Role of Environmental Conditions

1. Temperature effect:

High-temperature conditions accelerate the deterioration of the medium.
The temperature difference between day and night causes surface condensation.
Local overheating leads to the formation of thermal aging points.

2. Environmental pollutants:

Corrosive gases erode the outer shell.
The accumulation of dust affects heat dissipation.
Moisture penetration reduces insulation.

III. System-related Factors

1. Impact of supporting equipment:

The performance of the switching device
Reactance parameter matching degree
Reliability of the protection device

2. System harmonic conditions:

Harmonic resonance risk
High-frequency harmonic penetration effect
Harmonic superposition heating