Analysis Of Load Peak-Valley Time-Frequency Situation Of Wind Power Connected To Substation And Energy Storage Peak Shaving Strategy

With the continuous increase of power system load and the large-scale integration of wind power,the characteristics of the bus load of the power system substation have changed greatly,and the operation status of the power system is becoming more and more complex.Therefore,the analysis of the characteristics of the bus load of the substation and the optimization of dispatch have become the operation and optimization of the power system.The important work of planning.The peak and valley characteristics of the bus load curve of the substation can reflect the obvious characteristics of the regional load curve and the power consumption.The analysis of the peak and valley time-frequency situation of the bus load of the substation,and the influence of the wind power connection on the time-frequency situation of the load peak and valley of the substation bus can be used for the regional grid planning analysis To provide an effective theoretical basis,the participation of energy storage in peak shaving and optimal dispatch is of great significance to the source-load dispatch of the regional power grid.Based on this,the paper launched the following research.For the daily load of the substation bus,the basic concepts and methods of time-frequency analysis are introduced.The daily load peak and valley situation of the substation bus is defined in the time domain and the time-frequency domain,and the time-frequency of the daily load peak and valley of the substation bus is obtained based on historical data.Situation information,using the K-means clustering algorithm to cluster analysis of the daily time-frequency situation information of typical scenes,and then analyze the time domain and time-frequency domain indicators of the daily load peak and valley situation of the substation bus in each typical scene,and study the substation The correlation between the daily load peak and valley situation of the busbar in the time domain and the time-frequency domain,based on the first quarter actual historical SC AD A data of a 330kV substation 110kV bus in a provincial network to analyze the calculation example.Based on the busbar daily load peak-valley time-frequency situation information system,consider the wind power output model,analyze wind power output characteristics,calculate the time domain and time-frequency domain situation indicators in each scenario and analyze their correlation,and study the effects of different wind power penetration rates into the power system.The influence of the peak and valley time-frequency situation of the net load of the substation bus,and verify and analyze the actual data of the bus SCADA of the multiple hub substations of a certain provincial power grid.Aiming at the optimal scheduling of energy storage participating in peak shaving,a hierarchical optimization scheduling strategy for energy storage peak shaving that takes into account the time-frequency domain characteristics of load peaks and valleys is proposed.The system load peak-valley time-frequency index,system generating unit power generation cost,and carbon dioxide emissions are proposed.As the objective function,considering the energy storage power station equipment,system constraints and generator set constraints,a multi-objective hierarchical optimization scheduling model is established,and the fuzzy processing method is combined with the NSGA-II algorithm to solve the problem.The actual load of a typical spring working day in a certain province Verification of the effectiveness of the proposed method with thermal power unit data.The paper analyzes the peak-to-valley time-frequency characteristics of the daily net load of the substation bus and studies the energy storage involved in peak-shaving optimal dispatch.The proposed theories and methods can provide a certain theoretical reference for wind power integration into the substation grid planning and optimal dispatching operation.