Rearch On Microgird Control Based On Voltage Inverter

Traditional grid has got rapid development with the increasing demand ofpower, but its drawbacks gradually reflected out, high cost, operation difficulty,hard to satisfy the safety and stability need of customer.At the same time, withthe exacerbation of environmental pollution,people has paid more attention to theutilization of new energy, so the research on microgrid consisting of distributedenergy resources with minimal energy has been drawn much attention.Amicrogrid may comprise a set of inverter-interfaced distributed energy resourceswhose capacity is usually less than500kW, such as photovoltaic arrays, windturbines, microturbines, fule cells and so on. The distributed energy resourcesneed to connect with the central grid through power electronic equipment, soinverter control plays a important role in microgrid control.First, this paper introduces the concept, structure and control method ofmicrogrid, in view of most of the micro-sources of the microgrid are inverterinterfaced, the inverter modulation mode and commonly used microgrid invertercontrol strategies of microgrid are introduced in detail. The mathematical modelare formulated in dq axis frame to facilitate the PI control.Second, active power-voltage control strategy which is presented in recentyears is introduced in detail, the relationship between the micro-source of themicrogrid can be equal to the relationship of parallel inverter, this paper focuseson the parallel inverter control method. In traditional parallel inverter controlmethods, the master-slave control and peer to peer control method all haveshortcomings, in this article, the PQ control and active power-voltage controlcombined with active power-frequency characteristics are used in microgridcontrol. For three-phase voltage imbalance phenomenon, decoupled doublesynchronous reference frame phase-locked loop is used here to strengthen thesecurity and stability of the control method.Finally, voltage source inverter control model of microgrid is based on MATLAB/SIMULINK platform, the phase-locked loop technology is simulated;active power-voltage control strategy for microgrid in islanding operation issimulated, simulation results verify that droop control scheme works well in thiscontrol method, and can complete the microgrid inverter control primaryfrequency regulation, Simulation analysis of parallel inverters demonstrates thefeasibility of this method.