The article analyzes the existing systems of electromechanical transmission of mining trucks BelAZ. The influence of the load nature created by the uncontrolled rectifier on the power factor and mass-dimensional indicators of the electromechanical transmission isassessed. Variants of modernization of the AC-electromechanical transmission system are proposed, which provide power factor correction. The influence of the proposed options on the overall dimensions of the electromechanical transmission is considered. Based on the assessment, a modernization option was chosen that provides the required power factor with minimal impact on the overall dimensions of the electromechanical transmission. The results of modeling the operation of the existing electromechanical transmission and the modernized electromechanical transmission system using the most promising modernization option are presented.