The Peer-to-peer Control Of Microgrids And The Research Of The Operating Characteristic

With the development of the technology of distributed generation, the impact of the distributed generator on the grid becomes more serious. One of the solutions is the microgrids made up of the distributed generators and the local load. So the chief value of the microgrids is enhancing the reliability of power supply for consumers, while the requirements of the consumers are more than this. It is inevitable that the microgrids provide more service for the additional requirements of consumers. On the other side, the distributed generators are implemented via the interface of power electronic devices. It enhances the flexibility of the control for the distributed generators, but also increases the difficulty of maintaining the stability of the microgrids. The peer-to-peer control of microgrids takes full advantage of the flexibility of distributed and meets the requirements of consumers. This essay studies the peer-to-peer control strategies of microgrids with the inverter interface, and analyzes the characteristic of these control strategies. The primary coverage of the essay is as follows:First, summarizes and contrasts the different control strategies of microgrids. The primary objective of the peer-to-peer control of microgrids is to assign the power and share the load between the distributed generators without communication for decreasing the cost of microgrids and enhancing the reliability and flexibility. It should pay attention to that the peer-to-peer is necessary for plug-and-play. Then the essay summarizes the governing of power quality and economical regulating of the microgrids.Then the essay analyzes the principle and characteristic of the tri-phase inverter, and models the tri-phase inverter. The tri-phase inverter’s discrete state model is obtained. The dead beat control strategy is designed, and the characteristic of dead beat control is analyzed. The dead beat control of inverter is able to compensate the disturbance of the load current and the inverter interface becomes controlled voltage source. This control strategy is verified by emulation.The power output characteristic of distributed generator is analyzed, and the power loop control is designed on the basis of the dead beat control as voltage loop control.The droop control and inverse droop control are analyzed and contrasted as peer-to-peer microgrids control. The relationship between the distributed generators’output power and the frequency and voltage amplitude of microgrids is researched. The design of inverse droop control is elaborated. And the inverse droop control strategy is verified by emulation.On the basis of the inverse droop control, by imitating the frequency regulation of the traditional grid, the zero-error frequency regulation is designed. The feasibility the zero-error frequency regulation is proved and the load power assignment of the zero-error frequency regulation is obtained. And the zero-error frequency regulation control strategy is verified by emulation. The microgrids economical regulation is discussed on the third regulation of traditional grid.