Improved doubly-fed induction wind generator fault ride-through protection circuit

Abstract

The invention belongs to the field of wind power protection, and particularly relates to an improved doubly-fed induction wind generator fault ride-through protection circuit. The improved doubly-fed induction wind generator fault ride-through protection circuit comprises current-limiting circuits a, bypass circuits a, current-limiting circuits b and bypass circuits b, wherein one current-limiting circuit a is in parallel connection with one bypass circuit a, three groups of circuits in the above parallel relationship exist, one ends, those are, three phases of input ends U1, V1, and W1 are respectively connected with three phases of windings of a doubly-fed induction motor rotor in the doubly-fed induction wind generator, the other ends, those are, three phases of output ends U2, V2 and W2 are connected with three phases of AC output ends of a rotor-side converter in a doubly-fed induction wind generator converter structure; and three groups of current-limiting circuits b exist either in a delta connection or in a star connection, and leading-out wires are respectively connected with the above three phases of input ends U1, V1 and W1 through corresponding bypass circuits b. The problem that the doubly-fed is out of control in the case of traditional crowbar protection under most voltage fault conditions, and the transient characteristics and the fault ride-through ability of the doubly-fed induction wind generator can be improved.

Description

technical field [0001] The invention relates to the field of wind power protection, in particular to an improved fault ride-through protection circuit for double-fed wind turbines. Background technique [0002] In order to cope with the energy crisis and environmental degradation, countries around the world are actively promoting the development and utilization of renewable energy. Among them, wind power generation has become the focus of scientific research personnel and commercial enterprises. This is because wind energy is a reliable, unlimited, renewable source of electricity supply. The large-scale application of wind power can not only alleviate the energy crisis, but also reduce the environmental problems caused by the use of conventional energy, thereby reducing the emission of carbon dioxide gas. [0003] However, the integration of large-scale wind power into the grid has brought great challenges to the safe operation of the grid. Therefore, the new grid guideli...

AI Technical Summary

Problems solved by technology

[0009] Aiming at the defects in the prior art, the present invention provides an improved double-fed wind turbine fault ride-through protection circuit, which can solve the problem of doubly-fed motor runaway under most voltage faults, thereby stabilizing the system speed and suppressing the system speed during faults Increase too fast to support the grid voltage, thereby enhancing the fault ride-through capability of the doubly-fed wind turbine

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