In order that EMUs can leave the fault area as soon as possible when pantograph and catenary failures occur, or when waiting for rescue in the fault area, the air conditioning can continue to work, so as to improve the comfort of the waiting environment of passengers and reduce the passenger's dissatisfaction, a system and control method for EMUs to use battery power supply to complete emergency traction or emergency air conditioning was proposed. This method could realize the emergency self-walking function of the vehicle when the power supply failure occurs in any section of the line, and the air conditioning could work partially normally. Experiments showed that under the conditions of emergency traction and emergency air conditioning, EMUs could travel more than 20 km in emergency, which could greatly improve the efficiency of emergency disposal.