Abstract:I In order to guarantee the implementation of the monthly electricity trading schedule, an intra-month dynamic unit commitment method based on the expected completion rate is proposed to achieve an effective match between the unit operation mode, the completion of the electricity schedule and the subsequent supply and demand situation. In order to avoid frequent adjustments to the generating unit start-up and stop-down modalities, an indicator for the evaluation of the expected completion rate of the power plant is defined to quantify the risk of the planned implementation of electricity under the original generating unit combination modality. If the execution risk exceeds expectations, a dynamic portfolio of units is initiated for the month. The intra-month dynamic unit commitment is optimized to ensure the implementation of the monthly trading plan and the completion rate of each power plant is balanced, taking into account the power balance, network transmission capacity, unit capacity range and other constraints, can optimize the adjustment of the generation unit commitment on the subsequent operation days of the month. Finally, a case study based on the IEEE-30 buses system shows that the expected completion rate indicator can avoid frequent adjustment of the generator set combination method and ensure the reliable execution of the monthly trading plan of the power plant..