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In response to the current phenomenon of severe wind curtailment during the winter heating period in China’s "Three Northern Regions", deep adjustment of thermal power units can be achieved to reduce wind curtailment. Thus, this paper presents a bi-level optimization model for the combined heat and power system operation and multi-energy storage configuration. The lower model is the combined heat and power operation model of wind curtailment consumption with thermal storage electric boilers and electric energy storage devices. The goal is to minimize the total cost of combined heat and power unit operation, wind curtailment, environmental pollution, and large grid interaction. The upper model aims at the lowest cost of multi-energy storage configuration. Finally, the IEEE 9-node system is simulated using YALMIP and GUROBI. The results show that the proposed model is able to reduce the cost of the generation unit operation and environmental pollution, to guarantee full wind power consumption, and to reduce investment costs for energy storage systems.

With the development of economy, the power grid structure becomes more and more complex, and many new business scenarios and new requirements has emerged. The power system stability analysis method based on physical model was unable to accurately model the uncertain factors in the power system, which make difficulty to analysis the system. In this paper, a method of grid stability identification based on XGboost method has been proposed, and the state of power grid was determined from the grid multidimensional operation data. Firstly, the decision tree method was introduced. Secondly, introduced the principle and characteristics of classification and regression tree, and then introduced the XGboost principle and characteristics. Finally, the IEEE39 node system has been used to verified the correctness of the XGboost.

With the continuous improvement of renewable energy penetration, the inertia and primary frequency modulation capability of synchronous power grid are declining. If the virtual synchronous generator (VSG) technology is used for renewable energy generation, it can make due contribution to reducing the frequency variation and frequency deviation of the system under the impact of high power gap. The inertia support and primary frequency modulation function positioning in VSG research are not clear. In this paper, the inertia support function of VSG and its physical significance are analyzed, the expression of inertia support power of VSG is deduced, the location distinction between inertia support function of VSG and primary frequency modulation function is analyzed, and the different control function pairs of VSG in the process of large synchronous power grid frequency accident are simulated and analyzed,and study the effect of system frequency variation.