Research On Stable Operation Control Of Solar Photovoltaic Power Supply And Distributed AC Microgrid System

In this paper,the AC microgrid transmission system constructed for distributed photovoltaic power generation is mainly studied in four aspects:solar panel tracking mechanism,maximum power point tracking,hybrid energy storage and power transmission network port.In this paper,the comparison of uniaxial and biaxial tracking effects is carried out by means of simulation experiment and physical experiment.The azimuth-height biaxial tracking is selected as the solar illumination tracking mechanism,and the two-stage tracking structure and driving circuit of the four-quadrant detector are designed to realize the omnidirectional tracking of sunlight.At the same time,they are applied to the physical environment to verify the feasibility of the designed four-quadrant two-stage tracking photoelectric sensor.By comparing the automatic tracking mechanism with the fixed mechanism,it is verified that the azimuth-height two-axis automatic tracking mechanism is superior to the fixed mechanism,which can greatly improve the gain of the output power of the photovoltaic array.The MPPT tracking principle and control method are studied.The three traditional methods of perturbation observation method,constant voltage method and conductance increment method are simulated.When the photovoltaic array is partially shaded,the output characteristic curve will appear multiple extreme points.The traditional algorithm is prone to local optimization.In this paper,the maximum power tracking of the improved particle swarm optimization algorithm can jump out of the local optimization and find the maximum power tracking point in the global.Aiming at the problem of low-frequency voltage ripple and high-frequency voltage ripple on the DC bus side of photovoltaic,based on the analysis of the energy storage methods and principles of batteries and supercapacitors,combined with the advantages of the two,a hybrid energy storage control strategy is proposed to improve the transmission quality and power supply efficiency on the DC bus side,and improve the microgrid transmission network configuration.Through the improvement of the grid-connected inverter topology circuit and the improvement of the power port drive control method,the influence of photovoltaic power generation grid-connected on the stable operation fluctuation of AC microgrid is effectively reduced,which provides technical support for more consumption of photovoltaic power generation to realize photovoltaic grid-connected.