Steady-state calculation method and application of multi-level converter in permanent magnet wind turbine

Abstract

The invention provides a steady-state calculation method and an application of a multi-level converter in a permanent magnet wind turbine. Based on a wind speed value, an operating state of a wind energy conversion system is determined; based on the power interaction relationship between a permanent magnetic wind turbine and a multilevel converter, the mechanical power and the mechanical angular velocity of the permanent magnetic wind turbine under maximum power tracking control are calculated; a joint mathematical model of the permanent magnetic wind turbine and the multilevel converter is established in a synchronous rotating coordinate system; a direct-axis component and a cross-axis component of the output current of the multi-level converter in the synchronous rotating coordinate system are calculated, and the fundamental angle frequency and the DC side current are calculated; according to the interaction coupling relationship, a control signal calculation model of a multilevel converter sub module is constructed, and a sub module control signal is calculated by the model; a mathematical model of electrical quantities in the multilevel converter is established, based on the mathematical model, values of the electrical quantities in the multi-level converter are calculated, and the steady-state information of the multi-level converter is obtained.

Description

technical field [0001] The disclosure relates to a steady state calculation method and application of a multilevel converter in a permanent magnet wind power generator. Background technique [0002] The statements in this section merely provide background information related to the present disclosure and do not necessarily constitute prior art. [0003] As a clean and friendly energy source, wind energy is one of the fastest growing renewable energy sources and is gradually becoming an important alternative to fossil energy sources. The demand for wind energy has promoted the development of large-scale wind turbines, which has enabled commercial large-scale wind turbines to reach the megawatt-level capacity level. At present, 5 MW and 7 MW wind turbines have been assembled in offshore wind power at home and abroad, and 10 MW wind power The generator has also been studied in the laboratories of several wind turbine manufacturers. In the megawatt-level wind energy conversion...

AI Technical Summary

Problems solved by technology

However, the current research on MMC used in megawatt-scale permanent magnet wind turbines is still shallow, and it is urgent to calculate and analyze its steady-state characteristics

However, due to the complex coupling of the electrical quantities inside the MMC and the interaction with the permanent magnet wind turbine, there is currently no method for calculating its steady-state electrical quantities

This limits the application of MMC as a full power converter in megawatt permanent magnet wind turbines, and also becomes one of the limiting factors for the development of megawatt permanent magnet wind turbines to higher power.

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