Overload protection method for high-overload transformer

The invention provides an overload protection method for a high-overload transformer, and the method comprises the following steps: setting the number of segments of time-delay protection of the high-overload transformer, and setting the parameters of each segment; sampling current data; obtaining a current effective value, current period time and a current maximum value; comparing the maximum current value with each section of long delay current; for the section of current with the maximum current value smaller than or equal to the long delay current, updating or resetting the energy accumulation value of the section according to whether a long delay thermal memory switch of the section is turned on or not; accumulating the periodic energy value to the original energy accumulation value of the section to serve as a new energy accumulation value of the section for the section with the maximum current value larger than the long delay current; and when the new energy accumulation value of the section is greater