Research On The Grid-connected Operation Of The Microgrid With Renewable Energy Power Generation

Micro-grid exit with its flexibility, the advantages of control of power in renewable energy systems in a wide range of applications. Due to the innate power renewable power generation system, distributed renewable energy sources on the impact of distribution network voltage fluctuations, seriously affecting the system of power quality. This makes the grid limited absorptive capacity for renewable energy, causing a lot of abandoned, abandoning the wind light and local power supply reliability. Therefore, the study of renewable energy micro-grid, gridconnected operation it is necessary.According to Exchange bus type micro-grid lines when grid-connected capacity waste problems, abnormal state of charge of storage issues, and network voltage offset problems and proposes viable solutions and the simulation. Micro-mesh grid-connected capacity waste issues when using trend-oriented control of micro-mesh grid, out of transmission capacities limits and outlets can be power peak load shifting, reduce line transmission capacity in the planning and construction waste. For the State of charge of storage problems by considering the State of charge of storage strategy, ensure that the State of charge of storage in the normal range for a long time, so that the micro-grid system reduces energy overflow ratio and load power shortage rate. And network voltage offset problem, using the micro-grid network active hysteresis control, maintain the voltage fluctuations in the normal range, improves the security of micro-grid operation.Paper on micro-mesh grid economy operation is analyzed, presented grid based microeconomic operation of TOU price strategy. Fuzzy control algorithm integrated bi-directional time floating in the residual capacity of the battery and the power grid electricity prices and poor local load and generation of power, absorb or emit power control battery status and power, for users to obtain better economic benefits, improved the micro-grid grid economy.In terms of innovation, taking into account the State of charge of storage of the micro-power strategy is an innovation of this paper, its long run of rational use of energy storage devices in charge of normal status, thereby reducing energy overflow and load power outage from happening. In terms of energy storage device control, the paper calculated directly decomposed DQ axis current PQ value that is required, in the simulation process to be a more accurate and stable results. Controlled by inverter battery voltage, instead of directly connected to the battery of the chopper control, avoiding the chopper in the mode switch mode switch, to avoid the resulting in system instability.