Research Reverse Power Detection Method Micro-grid PV System Based On The Theory Of Transient

Solar energy as a clear renewable new energy gets the increasing favor of people, and that convertingsolar power into electrical energy is an important way to solve the energy problem. The grid generationmethod is worth to be considered to make solar power system play a practical value. However, theuncertainty of the load power in the power grid system may cause risk of solar electric power flow to themains.Given that the problem of reverse power could be produced in the process of the Grid-connectedPhotovoltaic System, a new idea, characteristic wave detection and control using the transient processtheory and transient protection theory in the power system is suggested. Namely, transient waves of allkinds of load can be captured by the sample processing system with a core of F28335DSP when some loadschange their current situation. Using FFT algorithm for sample data can get typical features carried by thetransient waves of all kinds of load, and the relationship between transient waves and loads change eventcan be confirmed. The reverse power event can be judged with characteristic waves model library bychecking electric power signal.In the small Grid-connected Photovoltaic test platform, a relay circuit controlled by key operation isdesigned to control the action of loads.Sampling circuit is designed to capture the transient wave when oneload changes its switching state. FFT algorithm is designed to analysis the sampling data. Matching andpositioning algorithm based on statistical indicators is designed to establish model library. The modelrealized100%correct recognition rate for load change event and80%correct recognition rate for specificload change event when it is tested in the test platform.