Subsynchronous oscillation analysis method based on broad learning system

This paper presents a method to analyze the Sub Synchronous Oscillation (SSO) problem based on broad learning system (BLS), which can quickly analyze the risk of SSO in a system and take measures. The simulation system is constructed by the eigenvalue analysis method to obtain training data, that solves the problem which is difficult to obtain actual data in SSO problem and makes the model more accurate and the conclusion more convincing. Subsequently, BLS is applied for feature extraction and the prediction model is constructed, the model can show the deep relationship between the oscillation source and topology of the system as well as various operating data, which is difficult to be expressed by formula. The system was tested and validated in the 41-bus system. The feature importance analysis method which comes from eXtreme Gradient Boosting (XGboost) algorithm is proposed and combined with the BLS prediction model, which can analyze the influence of each variable on the prediction results in different series compensation levels, and is validated in the 41-bus system, that makes the results of prediction more interpretable. Finally, the results of simulation show that the model can predict data with high accuracy and give adjustment plans for effective control of the system to avoid the risk of SSO

Coordinated optimization control strategy of hydropower and thermal power AGC units

With the rapid increase of penetration level of new energy power generation, the construction of auxiliary service market is facing new challenges. The stricter requirements of the power plant unit AGC are proposed by the power system. How to coordinate and control the output of hydropower and thermal power units to increase the use of hydropower while meeting the requirements of AGC regulation is a problem to be solved. Under the condition of interconnection of units in the whole network, an optimal control strategy for joint commissioning of hydropower and thermal power plants that meets the performance conditions of ‘two rules’ is proposed in this paper. The strategy establishes the connection between hydropower and thermal power units. Combined with the output characteristics and economic characteristics of hydropower units and thermal power units, a coordinated optimization control strategy model of hydropower and thermal power AGC units suitable for the ’two rules’ assessment rules is proposed for each objective and constraint condition in the joint scheduling of hydropower and thermal power. The optimal mathematical model with multiple objectives is constructed to realize the distribution of AGC among different types of power plants and units, which can give full play to the regulation ability of hydropower and thermal power. The proposed strategy achieves the efficient use of clean energy and reduces the grid’s overall operating costs to achieve energy conservation and emission reduction. Simulation results verify the superiority of the proposed strategy