Speed sensorless control method for doubly-fed wind turbine generator system

Abstract

The invention provides a speed sensorless control method for a doubly-fed wind turbine generator system. According to the control method, sliding-mode control and model reference self-adaption control are organically integrated, the stator current measurement value of a doubly-fed wind generator is selected to serve as a reference model, a stator current adjustable model can be obtained through stator flux linkage and the rotor current, a sliding-mode face is constructed through the cross products outputted by the two models, the rotor position and the rotating speed are obtained through the sliding-mode algorithm, and then the vector control strategy of the doubly-fed wind generator is achieved. The control technology algorithm is simple, cost of the generator can be reduced, complexity of hardware can be lowered, and the speed sensorless control method has high robustness for parameter changes and load disturbance of the doubly-fed wind generator, is high in reliability and easy to implement and has great engineering application value.

Description

technical field [0001] The invention belongs to the technical field of wind power generation, and in particular relates to a speed sensorless control method for a doubly-fed wind power generating set. Background technique [0002] As a clean and pollution-free renewable energy, wind energy is the most competitive unconventional energy. Variable-speed constant-frequency double-fed wind power generation technology has become one of the most popular wind power generation units due to its characteristics of high wind energy conversion efficiency, flexible connection of electromechanical systems, adjustable power factor, and small capacity of excitation converters. In the vector control of doubly-fed induction generator (DFIG), it is necessary to obtain the speed and position information of the rotor. At present, most of the doubly-fed units at home and abroad directly detect the speed by installing mechanical sensors such as photoelectric encoders, but the high-precision positi...

AI Technical Summary

Problems solved by technology

The double-fed wind turbine adopts the vector control technology without speed sensor, which can save the cable between the sensor and the controller, greatly improves the reliability of the wind power generation system with relatively harsh operating environment, and also solves the problem of the high-precision position sensor. Defects such as expensive, complicated installation, and heavy maintenance workload

[0003] In the Chinese invention patent application publication specification CN101388639A, a doubly-fed wind power generator position sensorless vector control method is disclosed. This method uses a model reference adaptive speed identification method based on the stator flux linkage. This method has good dynamic and static performance, but the main problems in the process of engineering application: (1) the prerequisite for this method must have the rotor excitation

(3) This method designs the observer in the static coordinate system, and the PI controller needs to adjust the complex gain coefficient, which is difficult to implement

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