Research On The Theory Of Grid-friendly Virtual Power Plant Regulation

Distributed energy has become an important solution to future energy crises due to its flexibility,environmental friendliness,and economic benefits.New energy sources such as wind and solar power have uncertainty and uncontrollability in their output,and are subject to output fluctuations due to environmental factors,which affects the consumption of electric power by the power grid.Virtual power plants aggregate various distributed energy sources into a whole that meets the requirements for power system operation,reliability,and grid connection through information technology,making them exhibit parameter characteristics similar to traditional power plants.In terms of integrating distributed energy and interacting with the main power grid,virtual power plants have more advantages than microgrids.This article focuses on the research of the functions and architecture design of grid-friendly virtual power plants(GVPP),GVPP planning and operation strategies considering renewable energy consumption,and GVPP preventive control considering emergency power support.The main innovative work is as follows:(1)In response to the evolution and regulation requirements of the power system under the dual carbon target,this article expounds the connotation of GVPP,defines the functional requirements,and designs the interactive mechanism of GVPP to support the safe and stable operation of the main power grid.Firstly,the evolution process of the power system under the dual carbon target is analyzed,and the challenges it faces in safe and stable operation are dissected.Then,the definition,composition structure,and functional characteristics of GVPP are elaborated,revealing its integration of massive heterogeneous distributed energy resources(DER)to interact friendly with the main power grid.Finally,a GVPP regulation architecture based on multi-agent technology is constructed,and its internal operation and participation in the safe and stable control of the main power grid are proposed.(2)Considering the uncertainty and volatility of renewable energy,a GVPP planning method and operation strategy considering renewable energy consumption are proposed.First,a low-pass filtering algorithm is used to deal with renewable energy fluctuations,and a gridfriendly virtual power plant two-layer planning model is constructed with the objective of minimizing renewable energy fluctuations and power abandonment and investment costs,and then solved using scalarization method,particle swarm algorithm and NSGA-II algorithm.Then,the GVPP operation framework is established,and the operating power of GVPP is optimized based on multi-objective particle swarm algorithm with the objective of reducing renewable energy fluctuation and GVPP power output variation on the long time scale.Finally,on the short time scale,wavelet decomposition is used to extract high-frequency prediction errors,which are combined with the real-time power state of GVPP to adjust.(3)Considering the adequacy of grid safety and stability control capability under highpower shortage accident scenarios,a preventive control method considering transient frequency regulation capability is proposed.First,an extended system frequency response model is constructed by taking into account the effect of GVPP active power response on the grid frequency dynamic process.Then,based on the least squares method,Levenberg-Marquardt algorithm and damped Newton method,the coupling relationship between GVPP control parameters and transient minimum frequency is extracted using the extended system frequency response model,and the instantaneous power and accumulated energy are integrated to quantitatively evaluate the frequency regulation capability.Finally,the critical FM capability to meet the grid frequency security requirements is estimated from the set of expected accidents to adjust the GVPP control parameters.