Abstract: A control method for low voltage ride through comprises the following steps: 1) A control circuit (9) monitors a DC bus voltage of a set of frequency converters (3, 4) connected between a wind generator rotor and a power grid (12) and a voltage of the power grid; 2) If the monitored DC bus voltage of the set of frequency converters is judged to be higher than a designed value, the control circuit controls a thyristor (7) in a crowbar protection circuit connected to the wind generator rotor to be closed to obtain a shunt protection; 3) After the thyristor is closed, the control circuit controls a stator breaker (1) which is connected between a wind generator stator and the power grid to disconnect the wind generator stator and the power grid; 4) After the stator breaker disconnects the power grid and the wind generator stator, the control circuit further controls a breaker (5) of a shunt circuit to be opened firstly and then be closed, the thyristor is turned off automatically, and thus the protection function

Abstract: The invention provides a reactive voltage control system and method for wind power field of double-fed wind power-generating unit. The system comprises dispatching center equipment, a power management module for the wind power field and a plurality of controllers for the double-fed wind power-generating unit, wherein the dispatching center equipment is used for calculating a reactive power set value of the wind power field; the power management module for the wind power field is used for distributing the reactive power set value in the wind power field; and the controllers for the double-fed wind power-generating unit are used for controlling corresponding double-fed wind power-generating unit to perform reactive power compensation. According to the reactive voltage control system and the reactive voltage control method for the wind power field of the double-fed wind power-generating unit, the reactive output capability of the double-fed wind power-generating unit can be fully exerted.

Abstract: A wind turbine generator system vibration detecting device and method are provided. The device comprises: a plurality of vibration sensors arranged on components of a wind turbine generator systems; at least one vibration switch arranged on a nacelle of the wind turbine generator system to detect a vibration signal of the nacelle and sends a fault signal to a control module if the detected vibration signal is larger than a turn-on threshold of the vibration switch; a vibration estimating module connected with the vibration sensors for processing vibration signals generated by the vibration sensors according to preset weighted values and a weighted formula in order to acquire a vibration state data, and comparing the vibration state data with a preset fault value and sending the fault signal to the control module if the vibration state data is not less than the fault value in accordance with the comparison.

Abstract: The present invention relates to a method and apparatus for judging an unnecessary windward condition and a method and system for tracking wind, wherein the method comprises: taking a first wind sample by using a wind sampling-detecting unit, detecting and obtaining a wind direction thereof; judging whether an intersection angle between the first wind direction and a current wind turbine orientation is smaller than a critical angle of rotation; if “yes”, determining the windward condition is unnecessary windward condition; if “no”, detecting a wind speed of the first wind sample, judging whether the detected wind speed is lower than a first critical wind speed; if “yes”, determining the windward condition is unnecessary windward condition; if “no”, determining the windward condition is not unnecessary windward condition, then rotating the cabin of the wind power generating set, thereby achieving accurate windward according to a wind condition, a cabin position, and so on.