Ground fault protection method and device for electric driving system of off-highway electric wheel vehicle

The invention provides a ground fault protection method and device for an electric driving system of an off-highway electric wheel vehicle. The method comprises the following steps: collecting direct current side full voltage and direct current side half voltage of the electric driving system of the off-highway electric wheel vehicle; determining whether a fault pulse of which the difference between the direct-current side half voltage and half of the direct-current side full voltage exceeds a preset threshold exists or not; if yes, determining that the electric driving system of the off-highway electric wheel vehicle has a grounding fault; under the condition that the electric driving system of the off-highway electric wheel vehicle has a grounding fault, determining the type of the grounding fault according to whether the number of the fault pulses in a preset sampling period exceeds a set value or not; and executing a corresponding fault protection strategy according to the type of the grounding fault. And