Abstract: ABSTRACT: Since the wet dewatering electric field of 2*350MW unit #1 and 2 furnace in xx thermal power plant has been put into operation, the wet dewatering electric field mistrip accidents have occurred for many times due to the trip of the wet dewatering heating fan and heater, resulting in the environmental protection index exceeding the standard and causing significant economic losses. In this paper, the control circuit of wet dewatering heating fan is analyzed theoretically, the existing problems are pointed out and the solutions are put forward.