Research On Virtual Synchronous Machine Technology Of Wind Farm Combined With SV

Driven by energy crisis and environmental problems,the power industry has ushered in a new era of actively exploring new energy generation and accelerating energy transformation and upgrading.The future power system will definitely be a new energy system dominated by renewable energy such as wind power.However,the inherent randomness,volatility and intermittedness of renewable energy as well as the high degree of power electronization of the system will bring unprecedented impacts and challenges to the safe and stable operation of the power system.For example,a large number of wind power connected to the power grid will cause a series of problems such as system voltage,frequency instability and inertia loss.It is urgent and necessary to study the new power system with "double high" characteristics in the future.In order to achieve the goal of "double carbon" on schedule and ensure the sufficient and efficient supply of clean electric energy to the whole society,the progress of wind power generation research must be accelerated.This paper focuses on the safe and stable operation of wind power generation system,and does the following research work.Firstly,by referring to the existing literature,the principles of wind power generation are understood,and the wind power system is studied in depth.Taking DFIG as an example,the wind turbine,system side,grid measurement and maximum power tracking(MPPT)control principles are learned.The characteristics and current problems of wind power generation in our country are also summarized.Secondly,simulation is an indispensable means to study wind power generation,but largescale wind farms contain hundreds of thousands of fans distributed in a vast area of tens of kilometers,limited by the storage capacity and processing capacity of the simulator,it is extremely difficult to conduct corresponding modeling and simulation research on the wind farm,because its model is a high-level model.The traditional processing method is equivalent processing of wind farm(single machine equivalent,multi-machine equivalent).The equivalent model simplifies the complexity of the system,reduces the computational pressure of the simulator and improves the simulation efficiency,but inevitably brings the model low accuracy,poor flexibility,weak applicability and other problems.In order to solve the above problems,this paper proposes an accelerated method for real-time simulation of the full topology of largescale wind farms,and verifies its effectiveness and accuracy through practical simulations,proving that the proposed method can greatly improve the simulation efficiency and simulation scale.Moreover,the randomness and volatility of wind power seriously threaten the safe and stable operation of the power grid,and become an important factor hindering the large-scale development of wind power generation.The stability of the voltage of the junction point is particularly prominent,and relevant improvement measures must be studied.To this end,the static reactive power generator(SVG)is deeply studied in this paper,and its working principle and control strategy are described in detail,and a simulation model is built.In view of SVG’s highly efficient and stable reactive power compensation capability,which can effectively maintain the voltage stability of grid junction,this paper applies cascade SVG to perform reactive power compensation for grid junction of wind power plant,so as to improve the operating stability of wind power plant and power quality.Finally,the low(weak)inertia and damping of future new power systems with "double height" characteristics are discussed.The latest virtual synchro control strategy is studied,and the virtual synchro control strategy of double-fed fan is proposed.The wind farm and SVG are combined to conduct simulation experiments.Through simulation,the effectiveness of the proposed control strategy is verified,which can simulate the operation characteristics of traditional synchronous generators,respond to the voltage and frequency regulation of the power grid,and reduce the impact of new energy on the power grid.Improve the inertia and damping of the power grid,improve the anti-disturbance ability of the system.