The Research And Development Of Micro-grid Stability Controller Bsed On Storage Unit

As power resource and environment problems become increasingly serious in recent years, the photovoltaic power generation and wind power generation which symbolize renewable energy power generation technology are supported via the national policies. Micro-grid, an crucial important form of usage of renewable energy power resource, draws much attention and focus.Micro-grid is able to resist to negative impacts when massive renewable energy power generations are combined to the main grid, improve the reliability and electrical power quality and so on. Due to the flexible operation ways controllable external properties and efficient usage of renewable power, there is practical sense on studying and spreading of micro-grid.Micro-grid operation models are divided into two parts:grid-connected model and isolated grid model. The reliable, stable operation and model shifting depend on support from energy storage devices. When micro-gird is operating at grid-connected model, energy storage devices can compensate the power fluctuation of renewable power, making the power between micro-grid and main gird controllable; when micro-grid is operating at isolated grid model, energy storage devices is used to hold the entire gird voltage guaranteeing the voltage and frequency operate in reasonable scale. According to the mentioned-above, energy storage device play a key role in micro-gird, the research and development of it is the basic work of micro-grid’s construction. In view of energy storage device’important status in micro-gird steady operation, the paper called it micro-grid stability controller.Firstly, various topologies of micro-grid stability controller are analyzed, ensuring reasonable topology of micro-grid stability controller based on practical conditions, meanwhile, the parameters of main devices are designed including transformer, LCL filter, switching devices, DC bus capacitors and lithium battery energy storage system.Then, in order to cater to the practical functions of micro-grid stability controller, the control system including DSP board, transformer board, signal conditioning board,drive board, rely board,touch screen and background monitoring system is designed based on DSP. The main circuit and control system are connected to realize a sample of micro-grid stability controller, based on which the phase-locked technology research and device functional test are carried out. Finally, the line resistance, micro-grid stability controller’s capacity and control strategy which have influence on voltage stability of micro-grid are analyzed and verified by simulation and experiment on condition that asynchronous wind generator is connected to micro-grid.