Abstract:The real time power balance is the key work to ensure the safe and reliable power supply. Based on the daily planning curve, the dispatcher adjusts the hydro power and thermal power output in real time to balance the supply and demand of the whole power grid according to the actual load and the output of the new energy power plant. Moreover, a series of section constraints are set to ensure the Safety and stability of the power grid under the condition of equipment ‘N-1’. Nowadays, with the vigorous promotion of the reform of the electricity market, new requirements are put forward for the fair, just and open adjustment of the power plants dispatching. This paper introduces the status of power balancing regulation in G province, which has the problems of low automation and high regulation frequency. Aiming at the existing problems, the paper presents some improvement measures such as AGC of thermal power plant level, AGC of cascade hydropower and related power plants of sending-out section, and puts forward three different periods of regulation, i.e. "thermal power regular"," hydro power regular "and "balanced adjustment". to complete a more automated, intelligent AGC control model modeling, which not only improve work efficiency, but also more sophisticated realization of the power plant output "San Gong" scheduling.