Design And Research Of Micro-grid Power Grid System

Micro-grid as a new energy generation has been called more and more widespread concern and attention. However, each micro-source connected micro-grid by power electronic devices. Power electronics interface make control more flexible, but also increase the difficulty of the corresponding control, which cause the control system becoming more complicated. Meanwhile, when the normal operation of the micro-network, we must consider the coordinated control strategy in order that each micro source should be operated reasonably and stably. In the micro-grid, because the wind, the light intensity and temperature conditions become randomness and uncertainty, the wind power and PV need tracking the maximum output power to be able to achieve the best energy efficiency. Therefore, the main contents include the following:1) Build a model of PMSM wind power, PV power generation model, the microturbine generation model, super capacitor energy storage model, active power filter models, and the inverter control mode for each model. Provides a basis for micro-grid simulation study.2) Build a micro-grid model, PQ control strategy operating in grid-connected, and m V/f control strategy operating in islanded, Droop control strategy; analysis the “master-slave” control strategy and the “peer to peer” control strategy through simulation.3) Aming at the best output tracking problem for wind power and photovoltaic power generation, we propose self-tuning control parameters Sliding layer extremes based search strategy. First prove the stability of the sliding mode control strategy based on the search of extremes; and propose the use of control with a lower frequency and lower noise of sliding mode control layer control function instead of a simple switch control function. Based on this, further methods proposed adaptive control parameters, the control system having a better control of quality, but avoiding human adjustment parameters cumbersome. Relatively solid theory, relatively simple to achieve, it has some engineering applications.