Study On Wind-thermal Power-storage Combined Frequency Modulation Operation Method

Vigorously developing and utilizing new energy represented by wind energy is an important way to achieve low-carbon power transformation.New energy generation is characterized by randomness and volatility.Large-scale grid-connected networks pose severe challenges to the frequency regulation of power systems.In some special conditions,the capacity of rotating thermal power reserve is limited,and the response speed is slow,and it is difficult to meet the demand for high frequency power systems of new energy systems.The variable-speed wind turbine generation itself does not respond to frequency changes in the system,but it can participate frequency regulation through a load shedding strategy.The energy storage system has the advantages of high power regulation speed,flexible charge and discharge power adjustment,and is a quality frequency modulation resource.The establishment of wind-thermal power-storage combined frequency regulation to realize the complementary advantages of various types of frequency-modulated resources is an effective means to improve the operational security of high-percentage new energy power systems.This dissertation focuses on the issues such as frequency modulation demand and control strategy of wind-thermal power-storage combined frequency control system.The research work has important theoretical significance and engineering practical value.This paper analyzes wind power fluctuation characteristics,load fluctuation characteristics,and equivalent load fluctuation characteristics and their effects on power system frequency through measured data.For the demand of high wind power permeability power system frequency modulation,the wind turbine generator was given up to abandon the maximum power tracking point operation mode to participate in the system frequency modulation;a general model to consider the physical parameters of the energy storage system was established,and inertial control and primary frequency modulation of the energy storage system were proposed.Control Method.Finally,a wind-thermal power-storage combined frequency-modulation operation method considering the different frequency modulation dead zones of different types of frequency modulation units and different power response speeds is proposed.Based on the example of the maximum operation mode of the Northeast Power Grid in 2014 under the PSASP/UPI simulation platform,the scenario where the two types of power systems are actually operating is designed for simulation analysis: the impact of large-scale power shedding on the grid frequency;the influence of wind power fluctuations on grid frequency,And verified the effectiveness of the wind-thermal power-storage combined frequency modulation operation method.