A doubly-fed wind power generator fault voltage ride-through control method and system

Abstract

The invention discloses a doubly-fed wind power generator fault voltage ride-through control method and system, comprising: obtaining the three-phase current of the doubly-fed wind power generator rotor, and obtaining the DC component after coordinate transformation of the three-phase current; and obtaining the DC component according to the dynamic voltage command value The d-axis current command value; the q-axis current command value is obtained based on the active power command value of the maximum wind energy tracking control; the modulation signal is obtained by adjusting the DC component, the d-axis current command value and the q-axis current command value through the current loop, and the rotor is generated according to the modulation signal The driving signal of the switch tube of the side converter is used to control the fault voltage ride-through of the doubly-fed wind turbine. It can dynamically change the control voltage command value to realize the reactive power exchange between the wind turbine and the grid, and improve the high and low voltage fault ride-through capability of the double-fed asynchronous wind turbine DFIG.

Description

technical field [0001] The invention relates to the technical field of wind turbine converter control, in particular to a fault voltage ride-through control method and system for a doubly-fed wind turbine. Background technique [0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art. [0003] In recent years, with the continuous increase of the proportion of wind power in the power grid, the installed capacity of wind power has reached a relatively high level. If the wind turbine does not have a certain ability to withstand power grid faults, passive protection solutions are still adopted in the event of grid voltage faults. It will increase the difficulty of fault recovery of the entire system, and may even deteriorate the security and stability of the power grid, which will eventually cause a chain reaction and lead to system collapse. Therefore, effective ride-through control...

AI Technical Summary

Problems solved by technology

Although this high-voltage ride-through method can meet the requirements of the wind power grid-connected code for the high-voltage ride-through capability of the unit during the voltage increase process, the implementation is relatively cumbersome, and the control mode needs to be switched based on the calculated overvoltage criterion.

[0006] The inventor believes that the above-mentioned schemes propose different solutions for the fault ride-through of wind turbines, but they all have certain limitations, that is, only a single fault ride-through can be achieved, and the two goals of high and low voltage ride-through cannot be achieved at the same time. The unification of control strategies during voltage swells and sags is relatively complex, or requires coordinated control with the power grid, or requires control mode switching, and the economic cost is higher

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