Abstract: The rapid switching device has the function of quickly realizing power source switching in the event of a power grid failure, meeting the requirements of continuous and stable power supply in the power system of chemical plants, and thus is applied in the power system of chemical plants. This paper successively and in detail introduces the selection of the rapid switching device, RTDS simulation tests, and dynamic load tests, and analyzes its application effect in the substation of a chemical plant through an actual case. The research results show that the rapid switching device can effectively ensure the continuity of production and reduce the risk of equipment damage, providing a strong guarantee for the continuity and safety of chemical production.