Research On Operation And Switching Strategy Between Microgrid And Off Grid

Affected by the natural environment and human factors, It is difficult to guarantee the stability of the micro network operation, This paper from the two aspects: the design of the control principle and control strategy of micro operation stability, The operation stability control strategy of microgrid is analyzed, and the design of the strategy for the smooth switching of the microgrid is analyzed and simulated, The specific content as follows:1. The current development situation of the micro network is studied, Combining with the domestic and foreign research level, and the problems in the operation stability of the micro network are analyzed.2. Starting from the structure of micro networks, the stability criterion of micro network is introduced in detail. Meanwhile, the overall control strategy of microgrid operation is analyzed. analyzed the principle about PQ control method, U/f control mode and droop control. in order to provides a theoretical basis to choice for the following control strategy.3. In the case of unbalanced power, the emergency control strategy for the stability of the microgrid is studied. Analyzed the strategy of emergency load / unit control and energy storage control strategy, In order to meet the requirements of the stable operation of microgrid system, the optimal load shedding algorithm based on optimal power flow of power system is adopted to minimize the total load shedding load. At the same time, the load and energy management system and the micro load forecasting method are introduced,the control method of load shedding control is improved.4. In the design of simulation model of microgrid operation and switching of inverter,filter part and control part was further added: To compare the effect of various waveform control strategy, select the T type filter and dual loop control inverter; According to the existing microgrid control strategy, improved the microgrid operation stability and smoothness of the design theory of control switch. The simulation model is built on the Matlab/Simulink platform to carry out the experiment. and the concrete simulation examples are enumerated, The operation stability and switching smoothness of the micro network are verified.