Grid-side circuit breaker and machine-side switch control strategy for converter of wind generating set

Abstract

The invention provides a wind generating set converter grid-side circuit breaker and machine-side switch control strategy which comprises the following steps: S1, acquiring the state of a wind generating set, and judging the current state of the wind generating set; S2, when the current state is that the unit is in a fault state, judging whether the fault is a converter fault or not; S3, if the current transformer fails, the current transformer does not respond to the torque instruction of the main control system any more, and the network side circuit breaker being disconnected; and S4, if thefault is a non-converter fault, the converter continuing to respond to the torque instruction of the main control system, the main control system judging the type of the generated fault and controlling the load shedding of the converter at the corresponding load shedding rate, and the converter controlling the modulation of the grid-side converter and the breaking of the grid-side circuit breakeraccording to the corresponding fault type. The strategy can reduce the opening and closing times of the grid-side circuit breaker and the machine-side switch of the converter to the maximum extent onthe premise of ensuring the safe and stable operation of the wind generating set, and prolong the service life of the circuit breaker.

Description

technical field [0001] The invention relates to the field of wind power generation, in particular to a control strategy for a grid-side circuit breaker and a machine-side switch of a converter of a wind power generating set. Background technique [0002] The wind power converter is one of the core components of the wind turbine. The grid side circuit breaker is used as the connection device between the converter and the box transformer. Its main functions are: first, to connect and disconnect the wind turbine and the box transformer under normal conditions. Second, when a serious fault occurs in the wind turbine converter system, the fault current can be cut off quickly, so that the converter can be disconnected from the grid to prevent the accident from expanding. However, the control strategy of the circuit breaker is usually determined by the converter factory according to the classification of the internal fault level of the converter, and the breaking strategy correspon...

AI Technical Summary

Problems solved by technology

However, the control strategy of the circuit breaker is usually determined by the converter factory according to the classification of the internal fault level of the converter, and the breaking strategy corresponding to the fault level is agreed by itself, which leads to different control strategies for the circuit breaker of different converter manufacturers. There are differences, which make the converter grid-side circuit breaker and / or machine-side switch have more opening and closing times under certain working conditions, which shortens the service life of the device and makes it unable to better adapt to the actual situation of the wind turbine. Application requirements

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