Wind turbine generator control method, controller and control system of wind turbine generator

Abstract

The invention provides a wind turbine generator control method, a controller and a control system of wind turbine generator. The method comprises the steps of acquiring the air velocity in front a hub by a distance two to three times the diameter of an impeller, the pitch angle of the impeller at the current moment as well as the rotation angular speed of the generator, calculating the pneumatic torque of the impeller, and calculating corresponding electromagnetic torque; acquiring the current torque given value and a pitch angle given value; and correcting the given value outputted by a torque controller or a variable-pitch controller. The controller comprises a pneumatic torque calculation module, a torque controller, a variable-pitch controller and a controller given value correcting module. The control system comprises a laser radar wind speed measurement instrument, a wind turbine generator, and the above controller. The wind turbine generator control system provided by the invention can respond to the wind speed change in advance to correct the variable-pitch and torque control effect so as to improve the wind energy utilization rate of the wind turbine generator, thereby obviating integral fatigue loads and power generation loss caused by impeller inertia and delay of the pitch-variable system.

Description

technical field [0001] The invention relates to the technical field of wind power generation, in particular to a control method, a controller and a control system for a wind turbine. Background technique [0002] In recent years, with the continuous progress of wind power generation-related control technologies, variable-speed and variable-pitch wind turbines have become the main installed type due to their advantages such as high efficiency of wind energy utilization and large single-unit capacity. [0003] When the variable-speed variable-pitch wind turbine is at low wind speed (below the rated wind speed), the main control system adjusts the pitch angle of the blades to the optimum (or minimum), and adjusts the impeller speed by controlling the electromagnetic torque of the generator to make the wind turbine work at the optimum speed. In the state of optimal blade tip speed ratio, to achieve maximum wind energy capture; when the impeller speed reaches the rated speed, the...

AI Technical Summary

Problems solved by technology

Due to the large moment of inertia of the impeller, the change of wind speed is reflected to the impeller speed, and then used to adjust the torque and pitch angle often lags behind for a long time

Especially when operating below the rated wind speed, in order to track the optimal tip speed ratio, it is necessary to continuously adjust the impeller speed according to the wind speed, but the torque at this stage in the existing main control system is the optimal value calculated according to the blade airfoil characteristics The product of the gain coefficient and the square of the generator speed is equivalent to an open-loop control method. The torque value obtained by this method is difficult to accurately track the optimal tip speed ratio, resulting in low wind energy utilization.

When the wind speed is above the rated wind speed, controlling the pitch angle according to the speed of the impeller will also cause the pitch angle to not match the current wind speed at the impeller due to the change of the speed and the lag of the pitch control system, so that the impeller and the tower bear a large load

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