In IGBT applications, Capacitors are crucial auxiliary components primarily used to address issues such as voltage spikes, current surges, and electromagnetic interference generated during high-speed switching processes. They are typically positioned at several key locations to ensure the stable, efficient, and reliable operation of the IGBT.
To help you understand quickly, the following provides a detailed analysis of the most commonly used IGBT circuits.
1.DC-Link Capacitors
Core function: As an energy buffer and voltage regulator for the system. It can provide the instantaneous large current required by the IGBT during high-speed turn-on, while absorbing interference from the power supply side and suppressing bus voltage fluctuations caused by sudden current changes, thus ensuring stable power supply.
2.Snubber Capacitors
Core function: Acts as a voltage spike absorber and switching stress suppressor. When the IGBT is rapidly switched off, the parasitic inductance in the circuit generates a high induced voltage (surge). This capacitor provides a discharge path for this energy, effectively clamping the voltage peak and protecting the IGBT from overvoltage breakdown.
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