The On-line Revising Algorithm And Application For Integrated Load Model Parameters Based On Daily Load Profile

In order to satisfy the requirements of operation and control requirements continuing to increase, the integrated load model need to be more accurate to reflect the characteristics of power grid. However, due to the geographical dispersion of load model and the random time-varying, it is hard to obtain an integrated load model which is reasonable to describe the load node that makes the integrated load model become an important factor affecting the improvement of power system simulation accuracy.According to the power system simulation and the random time-varying problems of substation integrated load model parameters, this paper presents an online modification method for load composition ratio in power industry in substation and load model parameters based on real-time daily load profile. It is obvious to see that the integrated daily load model power profile of substation is the superposition of daily load power profile of all users in its power supply area. The essential change characteristics of daily load profile of users is to reflect the load characteristics, so the daily load profile of users within the scope of substation power supply can be classified and integrated to obtain the daily load profile of typical industries, so that the daily load profile of substation is the superposition of daily load profile of typical electricity industry, it naturally contains the information that composes the industry for the integrated load of substation and naturally with time-varying. As long as this information can be extracted from daily load profile of substation online, we can achieve online modification for constitute a trade ratio of the integrated load. According to the above-mentioned basic idea, we can correct the composition ratio of electricity industry in substation online. Firstly, we can classify and integrated the daily load profile of electricity industry of users which is collected by the load control system and get the daily load profile of electricity industry, then establish an industry load characteristic matrix. According to the daily load power profile of substation obtained by SCADA system which synchronized in time with the above-mentioned daily load profile of users, and create a power balance equations for the daily load power sampling point of substation that associated with load characteristics matrix of industry, then solve the load capacity basis vectors of various industries. On this basis, by combining the load characteristics matrix of industry with load capacity basis vectors of industry, the typical composition ratio of electricity industry of integrated load of substation in each time point that corresponding to daily load profile can be obtained. Thus the online real-time correction of the load composition ratio of substation electricity industry and the load model parameters can be achieved.According to the method that is presented in this paper of real-time online modification for the load composition ratio in substation power industry and load model parameter, We choose to use the current mainstream Visual C++.NET integrated development environment (IDE), ADO database access technology, DLL technology and SQL Server design and development software platform. Simulation results show that, the Electrical characteristics that reflected by the composition ratio in power industry for integrated load based on daily load profile dovetails with the Characteristics of power load supply in substation, therefore method presented in this paper is effective. Monitoring data in SCADA and load control system can cover the full grid engineering background, the method has good practical value and it has been successfully applied to the online load modeling of actual provincial power grid.