A power conversion apparatus and a control method for a power conversion apparatus to reduce an amplitude of an output voltage of a converter when a grid is recovered from a fault, to ensure device safety. The power conversion apparatus includes a controller and a converter, and the controller is connected to the converter. The controller is configured to: after the output voltage of the converter is less than a first threshold, when the output voltage of the converter rises to be greater than a second threshold, reduce an active current output by the converter to a first current value, and reduce a reactive current output by the converter to a second current value, where the second threshold is greater than the first threshold.

A synchronous machine includes a stator with stator windings connected with stator terminals to an electrical grid and a rotor with rotor windings rotatable mounted in the stator, wherein a voltage regulator of the synchronous machine is adapted for outputting an excitation signal to adjust a current in the rotor windings for controlling the synchronous machine. A method for determining control parameters for the voltage regulator includes (i) receiving a first time series of values of the excitation signal and a second time series of measurement values of the terminal voltage in the stator terminals, (ii) determining coefficients of a system transfer function of the synchronous machine, and (iii) determining the control parameters for the voltage regulator from the coefficients of the system transfer function.

A method is provided for controlling the operation of a wind turbine, the wind turbine including a generator, a converter, a converter control unit, a wind turbine controller and a connection device to an external electrical power grid, wherein electrical power generated by the generator is input into the power grid via the converter, wherein the wind turbine controller is configured to determine a fault condition according to a fault condition signal and to active a safe operating mode in response to the fault condition signal indicating a fault condition, wherein the fault condition signal is determined by evaluating changes in an available output power signal generated by the converter control unit, the available output power signal describing the active output power available from the converter.

A method for controlling a converter, preferably a generator-side active rectifier of a power converter of a wind power installation, comprising: specifying a target value for the converter; specifying a carrier signal for the converter; capturing an actual value; determining a distortion variable from the target value and the actual value; and determining driver signals for the converter on the basis of the distortion variable and the carrier signal.

Overvoltage protection device for a variable-speed and constant-frequency electrical energy generation system includes at least one DC current generator connected, via a DC current bus to the input terminals of at least one inverter and to at least one regulation module for regulating the output voltage of the at least one inverter. The device includes a circuit including at least one switch in series with a resistor, the circuit being connected between the input terminals of the at least one inverter, at least one measurement sensor for measuring the DC voltage across the input terminals of the at least one inverter, a control circuit connected to the at least one measurement sensor and able to receive a voltage measured by the at least one measurement sensor, compare the measured voltage against a threshold and command the closure of the at least one switch if the measured voltage is greater than the threshold, and command opening thereof if not.

An apparatus for controlling a turbogenerator system when a power electronics circuit of the turbogenerator system is unable to provide a sufficient load on the turbogenerator to prevent the turbogenerator from accelerating uncontrollably is described. The apparatus includes a monitor including a first sensing device operable to detect a condition of the turbogenerator, and a brake controller responsive to a turbogenerator detection output from the first sensing device to issue a first brake control signal for operating a brake circuit to prevent the turbogenerator from accelerating uncontrollably and a second brake control signal for operating the brake circuit to permit resumption of normal operation of the turbogenerator.

A system and method for automatically tuning/configuring a power system stabilizer (PSS) in a power system digital excitation control system having an automatic voltage regulator (AVR) that includes providing a control input to the AVR as a function of generating a set of tuning PSS lead-lag phase compensation time constants as a function of received generated terminal voltages, generating an uncompensated frequency response as a function of the received set of generated terminal voltages and using particle swarm optimization (PSO) as a function of the generated uncompensated frequency response, generating a tuning PSS gain value as a function of a determined open loop frequency response of the power system, determining a PSS gain margin, determining a tuning PSS gain; and transmitting the determined set of tuning phase compensation time constants and the determined tuning PSS gain value to the control interface of the PSS.

A method and controller for controlling a Wound Field Synchronous Machine (WFSM) of an electric power generation system (EPGS) having a field winding and a stator armature winding is provided. The controller includes an adjustable component coupled to the generator and a power factor controller for adjusting the adjustable component to lower the power factor of the WFSM as a function of power output to a load of the EPGS to stabilize a current in the field winding.

A method for operating a multi-level bridge power converter of an electrical power system connected to a power grid includes receiving, via a controller of the power converter, an indication of a transient event occurring in the power grid or the electrical power system. The power converter has a plurality of switching devices arranged in an active neutral point clamped topology. Accordingly, upon receiving the indication, the method includes activating a crowbar algorithm programmed in the controller of the power converter to bifurcate a current received by the power converter into a plurality of different current paths defined by the plurality of switching devices.

A technique for providing electric power to an electric power utility grid includes driving an electric power alternator coupled to the grid with a spark-ignited or direct injection internal combustion engine; detecting a change in electrical loading of the alternator; in response to the change, adjusting parameters of the engine and/or generator to adjust power provided by the engine. In one further forms of this technique, the adjusting of parameters for the engine includes retarding spark timing and/or interrupting the spark ignition; reducing or retarding direct injection timing or fuel amount and/or interrupting the direct injection; and/or the adjusting of parameters for the generator including increasing the field of the alternator or adding an electrical load.