Method and device for detecting voltage flicker of grid-connected point of wind turbine generator system

Abstract

The invention provides a method and a device for detecting the voltage flicker of a grid-connected point of a wind turbine generator system. The method comprises the steps: sampling at an output end of a single fan to obtain a three-phase current signal and a three-phase voltage signal, separating and combining the obtained three-phase current signal and the three-phase voltage signal to obtain three ways of single-phase signals; respectively inputting the three ways of single-phase signals into a virtual power grid numerical value model and a virtual power grid circuit model, wherein the virtual power grid numerical value model is established according to a virtual power grid simulation phase voltage instantaneous value expression, the virtual power grid circuit model is established according to a virtual power grid phase diagraph and parallel resistors R are merged into two ends of a current source in the phase diagraph; measuring reference voltage us at a PCC point of the virtual power grid numerical value model and the voltage ud at a PCC point in the virtual power grid circuit model; measuring the flicker value pst1 of the reference voltage us at the PCC point and the flicker value pst2 of the voltage ud at the PCC point; and obtaining the flicker accuracy value of the voltage ud at the PCC point according to the flicker value pst1 and the flicker value pst2.

Description

technical field [0001] The invention relates to a power quality detection technology of a grid-connected point of wind power generation, in particular to a method and device for detecting voltage flicker at a grid-connected point of a wind power generating set. Background technique [0002] As more and more wind turbines are connected to the grid, the impact of wind power generation on the power quality of the grid has attracted widespread attention. [0003] The uncertainty of wind resources and the operating characteristics of wind turbines make the output power of wind turbines fluctuate. For example, during the continuous operation of grid-connected wind turbines, there are factors such as tower shadow effect, yaw error, and wind shear, and the torque generated by the impeller of the wind turbine is also unstable during one revolution. Torque fluctuations will also cause fluctuations in the output power of wind turbines. There are fluctuations in the output power of wi...

AI Technical Summary

Problems solved by technology

For example, during the continuous operation of grid-connected wind turbines, there are factors such as tower shadow effect, yaw error, and wind shear, and the torque generated by the impeller of the wind turbine is also unstable during one revolution. Torque fluctuations will also cause fluctuations in the output power of wind turbines

There are fluctuations in the output power of wind turbines, which may affect the power quality of the grid, and problems such as voltage deviation, voltage flicker, and harmonics may occur

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