Operation And Control Strategy Of Photovoltaic Power System In Microgrid

With the application of microgrid technology which improves the complementarity and integrated technical and economic benefits of different distributed generations(DGs) developed, microgrid has provided an effective way for large scale new and renewable energy connecting to the grid and generating. It meets China’s requires of new energy generation and sustainable development stand sustainable development strategy. Photovoltaic(PV) power, as an important part of DGs, its operation and control method when connected to the microgrid have great significance for study and broad prospect for application. This thesis mainly focuses on the PV system’s operation and control strategy which are suitable for the operation characteristics of microgrid. Firstly, it systematically analyzes the background, significance and research status of microgrid, details the existing operation and control strategies of microgrid. Secondly, this paper puts a further study on PV power which adopts PQ control strategy, and with dual current loop feedback, it proposes a detailed control system design of the inverter interface based on proportion resonance(PR) controller under αβ coordinate and gives reasonable design steps of controller parameters. Thirdly, a maximum power point tracking(MPPT) method integrating dynamically equivalent impedance matching and centered differentiation is put forward in this paper. With this method brought in, the maximum power point of solar cells can be tracked at a higher speed and with more precise detection accuracy. It also has advantages in optimization design for control system. Finally, on the basis of analyzing the output characteristic of PV power and operation characteristic of microgrid, this paper gives the local operation scheme of PV system using coordinated control strategy of PV power and battery storages, which makes PV system’s outputs controllable and reduces the negative impact for microgrid from PV system.