The major reasons for the bad data of real power system loads are analyzed and a bad data identification and correction method for two major kinds of bad data is presented. The method dredges the resource of energy management system (EMS) fully. In order to resolve the bad data resulting from automatic system fault of electric power systems

a new method of dynamic multi-source data disposal for the sum of electric load is proposed. The redundancy of the monitoring and transfer systems is exploited to insure the validity of the sum of load. Aimed at the identification of bad data caused by the big load accident

the method scans the ultimate big load one by one to prevent the misidentification of bad data. The new method has the advantages of high efficiency and validity for bad data identification and correction.