Correction method for front-stage and rear-stage nitrogen-oxygen sensors and related device

The invention discloses a correction method and related device for a front-stage nitrogen-oxygen sensor and a rear-stage nitrogen-oxygen sensor, and the method comprises the steps: after the exhaust temperature of a tight coupling SCR system accords with a preset temperature range, if the rotating speed deviation value and the torque deviation value of an engine and the ammonia-nitrogen ratio of the tight coupling SCR system in a first time period accord with preset stable working conditions, correcting the front-stage nitrogen-oxygen sensor and the rear-stage nitrogen-oxygen sensor; integrating the oxynitride measured values of the front-stage and rear-stage oxynitride sensors in the first time period to obtain the mass of the first oxynitride and the mass of the second oxynitride; calculating the consistency deviation value of the front-stage nitrogen-oxygen sensor and the rear-stage nitrogen-oxygen sensor in combination with the urea injection amount of the tight coupling SCR system; if the consistency dev