The Improved Dynamic Optimization Models For AGC Generators Dispatch In A Power System With Renewable Energies Under CPS

As an important part of the modern power system energy management, Automatic Generation Control(AGC) is an important means of maintaining the balance of active power, the quality of system frequency, and the tie-line power exchange. The regulating stratigies, ability, and performance of AGC directly affect the power quality and security of modern power grid. For decades, numerous research achievements about AGC have been made both in theory and practice. However, with the development of power system, especially the rapid development of renewable energies and the application of Control Performance Standard(CPS) of AGC, how to realize the optimized dispatch and configuration of AGC resource to satisfy the requirement of CPS standard, regional control performance and network security, has become a new research focus.This dissertation is supported by the project “Dynamic optimization of AGC dispatch strategies in a power system with renewable energies”, which subsidized by the National Natural Science Foundation of China(No. 51307186). The study is carried out for the problems involved in the AGC generators dispatch in modern power system, such as the CPS standard, network security constraints and uncertainties in renewable energies, etc. And the dynamic optimization model for AGC generators dispatch is improved and developed. The main contents and achievements are as follows:(1) An extended dynamic optimization model for AGC generators dispatch under CPS is proposed. The existing model for AGC generators dispatch still has some defects, such as neglecting the effect of network security constraints and power loss, etc. An extended dynamic optimization model for AGC generators dispatch under CPS is thus proposed in this paper with the following modifications: 1) the active power loss, loading limits through the branches and boundaries are integrated into the proposed model, 2) the original objective of ancillary service cost is revised, and 3) the completion of electricity production contract is added as a new objective function. The extended model is solved by an evolutionary programming algorithm considering the relatively dominant objectives. The modified IEEE 14-bus test system is used to verify the extended model proposed and the physical interpretation of dealing with CPS1 index as an objective and/or constraints is also discussed.(2) A chance constrained dynamic optimization model for AGC generators dispatch under CPS is proposed. The output power of renewable energies, such as wind power, is random. Thus, based on the theory of stochastic programming, a chance constrained programming model for AGC generators dispatch considering forecasting errors of renewable energies under CPS is proposed. The proposed model is solved by an adaptive evolutionary programming algorithm combined with Monte Carlo simulation or the point estimation method(PEM). A provincial power grid is used as a sample to verify the chance constrained model proposed, and the simulation results of Monte Carlo simulation and PEM are further compared and analyzed.