The standby power quick switching device can solve the continuous safe operation of auxiliary power problems. The paper firstly analyzes the basic principle of the quick switching device, and then discusses the possible impact of the quick switching device on the auxiliary power system, and summarizes the influences of different switching ways to the system. At last it concludes that to effectively improve the influences of the quick switching device to the system, we should increase the switching speed of the devices as possible to work in quick-switching mode, so that has certain significance to people of the actual power grid operation.