Contents I. Introduction
As the most important form of energy utilization in human society, electric energy has greatly promoted the development of social productivity. Electric energy is mainly converted through mechanical energy, such as wind power generationl'J, ship shaft power generation and flywheel energy storage are typical occasions for converting mechanical energy into electrical energy, but the source of the above-mentioned mechanical energy is unstable, and the power generation frequency and voltage amplitude are unstable, so that there are still some problems when the generator is connected to the grid. Permanent magnet synchronous generators [2] need external power electronic converters to achieve constant frequency stable power generation, which is costly and large. Brushed doubly-fed induction generators have achieved some success in the field of wind power generation [3], which regulates the rotor magnetic field of the motor by accepting the excitation voltage by brushes and slip rings to achieve stable power generation, but the slip rings and brushes need to be regularly inspected and maintained, and the cost is high. The above-mentioned problems can be avoided by adopting dual stator-winding induction generator[4], the rotor structure of dual stator-winding induction generator is cage type or winding type, the reliability of cage type rotor structure is better than that of permanent magnet structure when running at high speed, and a set of additional control windings is added on the stator side at the same time, when the rotor speed is reduced by external influence, the stability of voltage and frequency at the output end of the generator can be maintained by changing the size and frequency of the control winding current, the brush and slip ring are omitted, and the cost is significantly reduced.
