Reaseach On Wind-solar-Storage Hybird Power System Based On Three Level Inverter

As primary energy resources exhausted and environmental problems becoming inereasingly prominent, solar photovoltaic (PV) and wind power have become the most promising new clean energy. The technology of wind and solar hybrid power generation represented by PV and wind is focused by many countries. Wind and solar are complementary in the time distribution, the wind and solar power generation can compensate for wind or solar independent power system. On this basis, addition reasonable energy storage device not only can improve the efficiency of energy utilization but also make resource more sufficient using. So the study of wind-solar-storage hybrid power system has important significance.Firstly, a common PV model and a wind turbine model according to the mathematical models of PV cell and permanent magnet synchronous generator(PMSG) is established. In the rotating coordinate system, the direct drive type wind power generator mathematical is studied. A battery performance simulation model is established. The simulation results show that the established model can well reflect the power output characteristics. This chapter is ready for the next chapters.Secondly, a kind of energy coordinated control scheme appling for wind-solar-storage hybrid power generation system is explored. A method of maximum power tracking algorithm based on vector control method is put forward and a model to verify the feasibility of the present algorithm is established. A kind of storage control circuit that the current can flow on two-way is designed. A large current charge for the battery is adopted. The simulation results on the coordinated control scheme show that, the wind and PV can work on the maximum power point and the battery realize charging and discharging. Thirdly, neutral point clamped three level inverter realizes the voltage transformation with triangular carrier method and space vector control. The simulation results show that the space vector control is more sample and less harmonic content.Finally, based on the SVPWM the net-connected wind-solar hybrid power system model using the principle of d-q decoupling is designed. The PI control parameters of current and voltage loop respectively are designed according on typical type Ⅰ and type Ⅱ. The simulation results show that the designed controller can realize grid connecting with less current harmonic and the same frequency and phase with grid voltage.