The Double-Fed Induction Generator (DFIG) is a winding induction generator. It is the main component of constant frequency and variable speed wind turbines and one of the key components of wind turbine location. A.
The generator is mainly composed of two parts: the engine body and the cooling system. The motor body consists of the stator, rotor and bearing system. The cooling system is divided into three structures: water cooling, air-to-air cooling and air-to-water cooling [1].
The stator winding of the double-fed asynchronous generator is directly connected to the power grid, and the rotor winding is connected to the power grid through a frequency, voltage, amplitude and power converter. rotor phase. The power supply to the windings is automatically adjusted by the frequency converterfrequency According to the operation requirements, the unit can realize constant frequency power generation at different speeds to meet the requirements of electrical load and grid connection.
Due to the use of AC excitation, the generator and the electrical system form a "flexible connection", that is, the excitation current can be adjusted accordingly of the grid voltage, current and speed of the generator, and the output voltage of the generator can be precisely adjusted so that it can meet the requirements.