Electric vehicle insulation detection method

The invention provides an electric vehicle insulation detection method, and belongs to the technical field of electric vehicles. The electric vehicle insulation detection method comprises the steps that S10, a charging pile obtains the vehicle insulation resistance protection range of an electric vehicle; s20, measuring an initial pile insulation value through a pile insulation detector, and calculating upper and lower limit loading resistance values based on the initial pile insulation value and a vehicle insulation resistance protection range; step S30, loading the upper and lower limit loading resistance values on the charging loop, and verifying the vehicle insulation resistance protection range; s40, alternately performing insulation detection through a pile and vehicle insulation detector to obtain a pile insulation value and a vehicle insulation value; s50, an insulation error value is obtained based on the pile insulation value and the vehicle insulation value, and corresponding curves are drawn based