Research On Stability Control Of Chassis Integrated DC Micro-grid

In order to meet the high-power and impact load power requirements of self-equipped weapon systems(radar,missiles,artillery,protection,etc.),high-power/energy-density chassis integrated DC micro-grids have become one of the leading technologies at home and abroad.The chassis integrated DC micro-grid(DC-CIM)can work in different modes such as enhanced hybrid power,silent power supply,and charging maintenance.It has the advantages of reliable power supply,flexibility,and excellent power quality.The thesis focuses on load power boundary analysis and multi-modal stability control algorithms.It is of great significance to improve the load capacity and dynamic stability of the chassis integrated DC micro-grid.The paper analyzes and establishes a mathematical model of the components of the chassis integrated DC micro-grid.For the working modes of enhanced hybrid power,silent power supply,and charging maintenance,the method of hybrid potential function and Lyapunov eigenvalue is used to deeply analyze the chassis integration.Relationship between the load power boundary of the DC micro-grid and the electrical network parameters,and the specific mathematical expression of the power boundary is given.In order to explore the method of expanding the power boundary of the chassis integrated DC micro-grid,an in-depth study is carried out around the additional control based on virtual impedance control.Based on the system stability analysis theory of Lyapunov eigenvalues,a simulation model was built to verify the effectiveness of the method.In order to adapt to the non-linear and strong shock working characteristics of the load weapon system and improve the wide-range stable operation capability of the chassis integrated DC micro-grid,this paper develops a nonlinear robust stability control algorithm.For the engine driven self-excitation cage asynchronous generation system(EDS-CAGS),the control strategy combining the voltage-magnetic chain outer-loop Super-Twisting sliding mode control and the current inner-loop K-type function direct feedback linearization is analyzed in depth.For the hybrid energy storage subsystem,the back-stepping adaptive variable structure control based on accurate feedback linearization is analyzed in depth.The simulation verification results show that the control methods used are effective in adapting to the nonlinear and uncertain model characteristics of each subsystem,and have good robust control effects.Based on the above-mentioned research on the power boundary and the nonlinear stability control algorithm of the subsystem,the paper conducts a multi-modal overall joint simulation study of the chassis integrated DC micro-grid.Based on the instantaneous states of output power,load power,the capacity of the lithium iron phosphate battery and the super capacitor of each power generation unit,9 working sub-modalities of the chassis integrated DC micro-grid are established,and different working sub-modal switching strategies are analyzed.Under certain working modes such as enhanced hybrid power,silent power supply,and charging maintenance,the newly proposed nonlinear stability control algorithm and the traditional PI control algorithm are respectively adopted to carry out the overall joint simulation comparison for the chassis integrated DC micro-grid under the circumstance of large disturbance of load.The simulation results verify the effectiveness of the new nonlinear stability control algorithm to improve the stability of the chassis integrated DC micro-grid.