Surge Capacitors

We have two ABB generator circuit breakers. During overhauling we replaced the gaskets of the surge capacitors. Surge capacitors are used to help arc quenching during trip/opening of the circuit breaker. I want to understand how they help in achieving the goal?
As charge stoarge components, tend to hold instantaneous voltage constant.

Zero volts before breaker is opened, and following the usual cyclical changes afterwards. avoids the inductive kickback.