Research On Three-Phase Grid-Connected Inverter System With Harmonic Controller

Currently, in the face of energy crisis, people in the world actively develop new and renewable energy. Power is an important part between the forms of energy, and the three-phase grid-connected inverter is an important part of the power systems, so the research of the three-phase grid-connected inverter has become a major direction in the energy research naturally. This paper describes a three-phase grid-connected inverter system to study its design of software and hardware, and the method of improving the current quality.The topology of three-phase grid-connected is introduced firstly, and analysis the three types of filter:L-type filter, LC-type filter and LCL type filter in detail, and then according to their advantages and disadvantages to choose the right applications. This paper designs the main circuit topology of the system and the main components, including the inductors, the capacitors, and the switches according to the system requirements.The existing methods of grid current control of three-phase grid-connected inverter are analyzed, and the advantages of them are discussed. The control system is designed based on the system requirements. And a new harmonic controller in a synchronous frame is used in the control system. The design of the control system hardware is described.The design of the auxiliary power supply is introduced, it is a topology of multi output flyback with input-series output-parallel. A 6KW prototype is made to verify the design, the proposed system scheme is proved to be practical and effective by the experimental results.