Multi-point grounding fault detection method for secondary circuit of voltage transformer

The invention discloses a multi-point grounding fault detection method for a secondary circuit of a voltage transformer, and the method comprises the steps: detecting the secondary circuit through a plurality of parallel current sampling units, carrying out the grouping detection for many times according to a detection result, and carrying out the judgment of a grounding point of the secondary circuit of the voltage transformer according to the data comparison of the grouping for many times. A plurality of current sampling units connected in parallel can be utilized to disperse passing current, and unbalanced current can be effectively prevented from being generated after grouping and multiple times of detection; a plurality of current sampling units are connected in parallel to a secondary loop of the voltage transformer, and the other end of the current sampling unit is grounded, so that a current loop can pass through the current sampling unit at a non-grounding point, potentials at two ends of a grounding