Theoretical Study Of Automatic Optimal Power Flow Considering AGC

In current real power dispatch and control hierarchy of electric power system, the base values and participation factors of AGC units are determined by advanced dispatch. After that, in AGC time horizon the system status relies on AGC units only. Since the fixed control strategy, system has lost its constraint function, and power flow fluctuation might beyond our expectation, especially considering the integration of large amount of intermittent electric power source. Therefore, it's significant and meaningful for the security and economic operation in AGC time horizon to monitor system status accompanying with AGC process as well as to adjust base values and participation factors of AGC units in this time scale.It is hard to handle the system status in the course of AGC. Enlightened by the idea of electro-thermal coupling power flow and combined with the concept of dynamic power flow, a new idea of process power flow accompanying with AGC is proposed, a process power flow which is driven by ACE. This process power flow is on the basis of base values and participation factors of AGC units, determined by security economic dispatching, and on the basis of discipline of the changing of nodal distribution factor and power factor, provided by super short term load forecasting. By the merit of this idea, we could handle the system status and the continuous changing course of transmission line temperature. In order to realize this idea, this dissertation builds corresponding model and algorithm. Finally, a simulation is carried out to demonstrate the validity of the model and algorithm proposed in this dissertation, which indicates that it is important to handle the system status in the course of AGC, especially considering intermittent electric power source, because intermittent electric power source will make it harder to forecast the load changing. Besides, tracing the fluctuation of transmission line temperature is beneficial to the system security monitoring and corrective control.By the merit of process power flow and combined with AGC law, a concept of automatic optimal power flow is put forward. This dissertation established the corresponding model and analyzed its online application frame. Automatic optimal power flow could provide dispatch center with detailed variation process of power flow status, coordinate advanced dispatch and AGC organically and ensure the security and economic operation in AGC time horizon. The entire process is accomplished automatically, which is beneficial for the improvement of automation and intelligent of power system.