Logging depth correction computation method in logging system

The invention discloses a logging depth correction computation method in a logging system. The method comprises the following steps of: counting forward and reverse pulse signals fed back by a coding wheel and reflecting the forward and reverse conditions of a cable wheel disc; performing cable wheel disc abrasion correction and cable stretching correction on the counting values; and computing the actual logging depth according to the corrected counting values. The correction computation method can acquire a more accurate logging depth value so as to provide support for acquiring accurate logging data to well meet the current logging operation requirement. Thermal redundancy backup technology is adopted in a key signal processing module in the logging system so as to improve the operatingreliability of the system and ensure the equipment safety of the logging operation.