I. What is electrolytic capacitor:
1. Electrolytic capacitor, as the “energy storage heart” of charger power module, bears the key tasks of filtering, voltage stabilization and transient response. Its large-capacity characteristics (up to tens of thousands of μF) can effectively absorb the pulsating current after rectification, reduce output ripple, and ensure that the charging process is stable and efficient. Especially in fast charging scenarios, the fast charging and discharging capability of electrolytic capacitors can cope with high power transient demands and avoid voltage dips.
II. single-phase and three-phase power requirements:
Current Characteristics:
The current waveform of single-phase power is sinusoidal, and there is a periodic zero-crossing point, resulting in fluctuations in power output.
Three-phase power three-phase current phase difference 120 °, the total power output is smoother, less pulsation.
Filtering requirements:
Single-phase alternating current, after rectification, produces a large ripple voltage (voltage fluctuation). Electrolytic capacitors with large capacity characteristics can store charge and release energy, smoothing voltage fluctuations and reducing damage to equipment.
Energy storage compensation:
When single-phase power is interrupted near the zero-crossing point, electrolytic capacitors can provide short-lived energy support to ensure continued equipment operation.
Power Factor Correction:
Some single-phase equipment (such as switching power supplies) can cause current waveform distortion, electrolytic capacitors with other components can improve power factor and reduce power waste.
III. Ripple voltage effects:
Equipment Damage: High ripple voltage may cause electronic components to overheat, especially capacitors and semiconductor devices, which may shorten their life or be damaged outright in long-term operation.
Signal interference: in sensitive electronic equipment, ripple may introduce noise, affecting the signal quality, such as in audio or video equipment to produce noise or interference.
Power Loss: Ripple can lead to additional power loss because current needs to be constantly charged and discharged, increasing the burden on the system and reducing efficiency.
Equipment malfunction: Some control circuits are sensitive to voltage fluctuations, and excessive ripple can lead to false triggers or logic errors, affecting system stability
IV. Protective measures:
Connect polarity correctly:
Electrolytic capacitors have positive and negative polarity, the installation must strictly check the circuit diagram to ensure that the polarity is connected correctly. Reverse connection will lead to rapid heating inside the capacitor, liquid leakage or even explosion For occasions that require a non-polarized capacitor, it can be realized by connecting two electrolytic capacitors of the same polarity in series.
Temperature management:
1. Operating temperature control: the ambient temperature should be lower than the nominal range of the capacitor (usually -40℃~+105℃), avoid close to the heat generating components.
2. Heat dissipation design: For high power scenarios, heat dissipation can be assisted by heat sinks or fans, and make sure to leave 3-5mm of space around the safety valve to release internal pressure.
Regular inspection and maintenance:
1. Appearance Inspection: Regularly check for bulging, leakage or deformation of the outer skin, and replace abnormal capacitors in time.
2. Parameter monitoring: Measure the capacity and leakage current by multimeter or capacitance meter, and replace it if the capacity drops more than 20% or the leakage current increases significantly.
3. System harmonic management: add filters in the circuit where harmonics exist to reduce the damage of high frequency components to the capacitor.
