Research On A Coordination Control Strategy Of PV/Micro-turbine Hybrid Micro-grid

Photovoltaic power generation system(PV)has become the fastest development of the way in new energy power generation and has unlimited potential,because of the wide range of distribution,and simple,inexhaustible,clean and other advantages of environmental With the increasing scale of modern power system,the system is more and more complex,the stability of photovoltaic grid-connected power quality has a vital role.Small and medium-sized photovoltaic power plant as a distributed power supply,will affect the stability of the entire system if the PV power fluctuations after connected to grid.In view of this,the PV and Micro-turbine hybrid micro-grid coordination control strategy by using controllable micro-turbine to smoothing the fluctuation of PV power and voltage and improve the stability of hybrid microgrid is proposed in this paper.Firstly,this paper introduces the basic characteristics and working principle of the photovoltaic power generation system in detail,and builds the PV grid-connected system model.The inverter is used to ensure the smooth access of the PV power grid:the basic characteristics of the micro-turbine grid-connected power generation system are studied in detail and the working principle of the micro-gas turbine power generation system control strategy,set up a micro-gas turbine power generation system model.Then,in order to achieve the coordination of Photovoltaic/Micro-turbine system grid-connected control,to smooth the output of photovoltaic power generation system,and to support the control of grid voltage control purposes.The paper design of the rectifier,inverter control method of the photovoltaic power generation system and micro-turbine power generation system respectively.The rectifier uses a dual-ring control using a power-voltage outer ring and a current inner loop.The inverter uses dual closed-loop PI control combined with output power and inductor current feedback.In the micro-grid,the PV system share the base-load of the local load,while the micro-turbine share the remaining loads.In order to coordinate the output of the micro-source for control purpose,calculating the algorithm of the control strategy,the output value of the control method is obtained by calculating the output power of the photovoltaic and micro-turbine power generation system and the grid point voltage.Finally,The system simulation model is established by using PSCAD/EMTDC and the dynamic response performances of the Coordination Control Strategy of PV/Micro-turbine Hybrid Micro-Grid are tested under various operating scenarios such as hybrid power generation system of the micro-source output power changes,voltage fluctuations and so on.The simulation results verify the feasibility and effectiveness of the proposed architecture and the coordination control strategy.