The method of control according to the invention slaves a DC voltage generated by the alternator to a predetermined setpoint value by controlling an excitation current flowing in an excitation circuit comprising an excitation winding of a rotor of the alternator. The excitation current is controlled by means of a semiconductor switch, in turn controlled by a control signal having a predetermined period. The method comprises a detection of a failure of the excitation circuit. At least one short-circuit of the excitation winding is detected. According to another characteristic of the method, the control signal is generated on the basis of a combination of a setpoint signal formed by pulses of the predetermined period exhibiting a duty ratio representative of the setpoint value and of a detection signal indicative of the short-circuit.

The method of control according to the invention slaves a DC voltage generated by the alternator to a predetermined setpoint value by controlling an excitation current flowing in an excitation circuit comprising an excitation winding of a rotor of the alternator. The excitation current is controlled by means of a semiconductor switch, in turn controlled by a control signal having a predetermined period. The method comprises a detection of a failure of the excitation circuit. At least one short-circuit of the excitation winding is detected. According to another characteristic of the method, the control signal is generated on the basis of a combination of a setpoint signal formed by pulses of the predetermined period exhibiting a duty ratio representative of the setpoint value and of a detection signal indicative of the short-circuit.

Detection of electric power generator stator ground fault conditions and protection of the generator due to such conditions is provided herein. In one embodiment, a generator protection element may calculate generator third harmonic voltage quantities using measurements from the generator terminals, and determine a stator ground fault condition using the calculated generator third harmonic voltage quantity. A tripping subsystem may issue a trip command based upon detection of a stator ground fault condition.

Detection of electric power generator stator ground fault conditions and protection of the generator due to such conditions is provided herein. In one embodiment, a generator protection element may calculate generator third harmonic voltage quantities using measurements from the generator terminals, and determine a stator ground fault condition using the calculated generator third harmonic voltage quantity. A tripping subsystem may issue a trip command based upon detection of a stator ground fault condition.

Detection and protection against electric power generator stator ground fault conditions in multiple-generator high-impedance grounded installations is provided herein. In one embodiment, a generator protection element may block a determination of a fault using third harmonic voltages when the third harmonic voltage from the generator is less than a factor of the maximum third harmonic voltage from all of the generators on the common bus. A tripping subsystem may issue a trip command based upon detection of a stator ground fault condition.

Detection and protection against electric power generator stator ground fault conditions in multiple-generator high-impedance grounded installations is provided herein. In one embodiment, a generator protection element may block a determination of a fault using third harmonic voltages when the third harmonic voltage from the generator is less than a factor of the maximum third harmonic voltage from all of the generators on the common bus. A tripping subsystem may issue a trip command based upon detection of a stator ground fault condition.

The present disclosure is directed to a protection system for a wind turbine power system connected to a power grid. The protection system includes a main brake circuit having at least one brake resistive element and at least one brake switch element, a battery system, and a controller. The brake resistive element is coupled to at least one of a DC link of a power converter of the wind turbine power system, windings of a rotor of the generator, or windings of a stator of a generator of the wind turbine power system via the brake switch element. The battery system is coupled to the generator via a battery switch element. In addition, the controller is configured to disconnect the power converter and the generator from the power grid and connect at least one of the main brake circuit or the battery system to the generator in response to detecting an electromagnetic (EM) torque loss event so as to generate an EM torque.

Techniques are described for operating a wind power facility in order to provide reactive power support to a power grid. The wind power facility may be a wind turbine or a wind power plant. An exemplary method includes increasing an amount of reactive power injected into the power grid, decreasing an amount of active power injected into the power grid by a certain amount, and dissipating and/or storing substantially the certain amount of active power.

A generator circuit breaker includes a main current branch, a current-limiting transfer branch, a freewheeling branch and a fast switch. The main current branch includes a high-speed mechanical switch S1 and a high-speed mechanical switch S2 in parallel, wherein two ends of each of breaks of the high-speed mechanical switch S1 and the high-speed mechanical switch S2 are directly connected with wire outlet ends of the circuit breaker respectively. One end of the current-limiting transfer branch is connected in parallel to one end of the main current branch and the other end of the current-limiting transfer branch is connected with the other end of the main current branch via a fast switch S3, wherein the current-limiting transfer branch includes a transfer capacitor C, an inductor L, thyristor components T1 and T2, and a current-limiting resistor R.

A generator circuit breaker includes a main current branch, a current-limiting transfer branch, a freewheeling branch and a fast switch. The main current branch includes a high-speed mechanical switch S1 and a high-speed mechanical switch S2 in parallel, wherein two ends of each of breaks of the high-speed mechanical switch S1 and the high-speed mechanical switch S2 are directly connected with wire outlet ends of the circuit breaker respectively. One end of the current-limiting transfer branch is connected in parallel to one end of the main current branch and the other end of the current-limiting transfer branch is connected with the other end of the main current branch via a fast switch S3, wherein the current-limiting transfer branch includes a transfer capacitor C, an inductor L, thyristor components T1 and T2, and a current-limiting resistor R.