Abstract: Based on examples, the process of electricity interference and its harm to the continuous production of chemical enterprises are analyzed. A fast switching mode based on the principle of electromagnetic repulsion is described, which simulates fast switching at the short-circuit fault time to cut off the fault within 20ms or maintains the bus voltage in cooperation with the equivalent impedance, so that the sensitive equipment such as relay, contactor and frequency converter without low-voltage crossing function does not shut down.Several electricity anti-interference measures are compared, and analyses are performed on the new applications of fast switching in the electricity anti-interference field of power systems.