what is the impact of power capacitor's capacitance

The capacitance value of power compensation capacitors affects the system in the following key aspects:

1. Power Factor Improvement:
The selection of capacitance directly influences the system's ability to compensate for reactive power. An insufficient capacitance value fails to effectively improve the power factor, while excessive capacitance may lead to over-compensation, resulting in system overvoltage.

2. System Voltage Fluctuations:
Oversized compensation capacitor capacity can cause grid voltage rise. Particularly under low-load conditions, over-compensation may occur, potentially elevating voltage beyond equipment tolerance limits and leading to device damage or failure.

3. Harmonic Impacts:
When power compensation capacitors operate alongside non-linear loads (such as frequency converters or electric arc furnaces), inappropriate capacitance selection can exacerbate harmonic issues. Larger capacitance values may resonate with harmonic frequencies in the system, amplifying harmonic currents and compromising power quality.

4. System Stability:
Excessive capacitance can alter the transient characteristics of the system. During grid disturbances or load fluctuations, this may reduce system stability, potentially causing voltage spikes or dips.

5. Equipment Lifespan:
Oversized capacitance may subject power compensation capacitors to frequent charging and discharging cycles, thereby shortening their service life. Excessive charging currents can lead to overheating or breakdown failures.