About DC-Link Capacitors
In an inverter system, DC-Link capacitors stabilize voltage after the rectifier, filtering out the AC ripples on the DC bus. Voltage ranges for the DC bus are typically 450V to 1500V but will depend on the end application. The close proximity to switching devices (e.g. MOSFETs or IGBTs) means that DC-Link capacitors are subjected to a higher operating temperature. The switching frequency of the ripple could be in the range of 1kHz to 20kHz.
Metallized Polypropylene film capacitors are ideal for DC-Link applications due to the relatively high voltages and high frequencies used. The high dielectric strength means long life and resistance to high voltage transients. The low dielectric absorption of polypropylene means minimal self-heating due to high frequency.
特性
- Self-healing
- High capacitance density
- ±5% capacitance tolerance
- High ripple current
- -40°C to +85°C temperature range
- Low losses
- High contact reliability
- Suitable for high-frequency applications

