Abstract: A system for controlling a grid connected power generating system is provided. The system includes a wind turbine, a converter, a first controller and a second controller. The wind turbine supplies electrical power to a power grid and the converter couples the wind turbine to the power grid. The first controller calculates voltage commands to emulate a phasor back electromotive force behind an inductance. The controller further generates converter switching commands from the voltage commands. The voltage commands include a voltage magnitude reference and an internal frequency reference calculated from a power imbalance between an active power reference and the electrical power. The second controller is used to limit a converter current.

Abstract: A solar farm system is provided that is configured for reducing electrical loss. The solar farm system includes a plurality of PV arrays coupled to inverters and a collector system including a conductor or network of conductors. The collector system also includes a plurality of transformers with one or more transformers connected between the inverters and the conductors. The solar farm also includes a substation transformer connecting the solar farm collector system to the electrical grid. The solar farm includes a control system configured to determine at least one operating parameter for the solar farm system to reduce electrical loss and to regulate the collector system and the plurality of inverters based at least in part on the at least one operating parameter.

Abstract: A system and method for controlling power ramp rate of a wind farm is provided. The wind farm includes a plurality of wind turbine generators and a wind farm control system. The wind farm control system is operable to monitor rate of change of collective power output of the wind turbine generators, and to limit the rate of change of collective power output by generating a power output rate limiting signal based on the monitored rate of change of collective power output of the wind turbine generators and a desired collective power ramp of the wind turbine generators and applying the power output rate limiting signal to the plurality of wind turbine generators.

Abstract: A power generation system includes a converter configured for supplying power from a constrained power or energy source to a power network and a control system configured for balancing instantaneously available power from the constrained source against demanded load from the power network by dynamically adjusting power network voltage, power network frequency, or a combination of power network voltage and power network frequency.

Abstract: A wind turbine generator includes at least one rotating member, at least one stationary member, and a clearance gap control system. The stationary member is positioned such that a clearance gap is defined between a portion of the rotating member and a portion of the stationary member. The clearance gap is configured to facilitate transmitting a controllable magnetic flux therethrough. The control system includes at least one clearance gap measurement assembly, at least one power converter, and at least one controller. The controller is coupled in electronic data communication with the assembly and the converter and is configured to modulate a dimension of the gap by modulating the flux.

Abstract: A power generation system including a photovoltaic (PV) module to generate DC power is provided. The system includes a combination of a DC to DC converter and a DC to AC converter coupled to the DC to DC converter for supplying power from the PV module to a power grid. The system further includes a bidirectional converter and an energy storage device coupled to the bidirectional converter. The system also includes a control system to generate commands for controlling a state of charge of the energy storage device. The control system comprises a deadband limiter to detect a deviation of the frequency signal outside of a respective signal range, a power shaper to provide a transient power generation adjustment signal in response to the signal being outside of the respective signal range and a limit controller for preventing the adjustment signal from causing the energy storage device to operate outside of at least one operating constraint.

Abstract: Commands are generated for controlling a state of charge of an energy storage device coupled between an energy source and an auxiliary load. Commands are also generated for providing from the energy storage device to the auxiliary load and for using power from the energy storage device for controlling a DC link voltage, energy source torque, grid side power flow, or combinations thereof. Commands may also be generated to provide frequency compatible power to auxiliary loads of the energy source.

Abstract: A protective circuit for a multi-level converter including a DC link capacitor bank includes: an energy absorbing element; switches, wherein at least two of the switches each couple the energy absorbing element to the capacitor bank; and a controller configured to provide control signals to the switches to selectively actuate the switches to enable control of energy dissipation and to enable control of voltage balance on the capacitor bank of the multi-level converter.

Abstract: A stabilization system for a power generation system including non-conventional energy source coupled to a utility grid, the stabilization system comprising: a deadband limiter configured for detecting when a signal of the power generation system is outside of a signal range; a power shaper configured for providing a transient power generation adjustment signal in response to the signal being outside of the signal range; and a limit controller to configured to prevent the adjustment signal from causing the energy source of the power generation system to operate outside of at least one operating constraint.

Abstract: A system, a method, and an article of manufacture for controlling operation of an electrical power generation system are provided. The electrical power generation system has a plurality of electrical generators electrically coupled to an electrical grid. The method includes obtaining a first output parameter value associated with the electrical power generation system. The method further includes determining an error value indicative of a difference between the first output parameter value and a desired output parameter value. The method further includes determining a first gain value based on at least one of the first output parameter value and a time-varying operational parameter of the electrical power generation system. The method further includes determining a first power value based on the error value and the first gain value.

Abstract: A system for controlling torque ripple in a permanent magnet synchronous machine includes a power converter configured to be coupled to the permanent magnet synchronous machine and to receive converter control signals and a system controller coupled to the power converter. The system controller includes a fundamental current controller configured for providing fundamental voltage commands, a harmonic current controller configured for using harmonic current commands, current feedback signals from the permanent magnet machine, and fundamental current commands in combination with positive and negative sequence regulators to obtain harmonic voltage commands, and summation elements configured for adding the fundamental voltage commands and the harmonic voltage commands to obtain the converter control signals.

Abstract: An integrated thermal management system is provided. The system includes a first device configured to release a first heat loss and coupled to an integrated cooling system. The system also includes at least a second device configured to release a second heat loss and coupled to the integrated cooling system. The system also includes at least one heat exchanger configured to release the first heat loss and the second heat loss to ambient.

Abstract: A protective circuit for a multi-level converter including a DC link capacitor bank includes: an energy absorbing element; switches, wherein at least two of the switches each couple the energy absorbing element to the capacitor bank; and a controller configured to provide control signals to the switches to selectively actuate the switches to enable control of energy dissipation and to enable control of voltage balance on the capacitor bank of the multi-level converter.

Abstract: A method for determining electric currents for an electrical machine includes generating a first real power current demand signal and a first reactive power current demand signal. The method also includes determining at least one of a second real power current demand signal and a second reactive power current demand signal by prioritizing a second real power current demand signal over a second reactive power current demand signal. Alternatively, the method also includes determining at least one of a second real power current demand signal and a second reactive power current demand signal by prioritizing the second reactive power current demand signal over the second real power current demand signal. The method further includes comparing at least one of the first real power current demand signal and first reactive power current demand signal to at least one electrical machine current limit signal.

Abstract: A wind turbine generator includes at least one rotating member, at least one stationary member, and a clearance gap control system. The stationary member is positioned such that a clearance gap is defined between a portion of the rotating member and a portion of the stationary member. The clearance gap is configured to facilitate transmitting a controllable magnetic flux therethrough. The control system includes at least one clearance gap measurement assembly, at least one power converter, and at least one controller. The controller is coupled in electronic data communication with the assembly and the converter and is configured to modulate a dimension of the gap by modulating the flux.

Abstract: A method for determining electric currents for an electrical machine includes generating a first real power current demand signal and a first reactive power current demand signal. The method also includes determining at least one of a second real power current demand signal and a second reactive power current demand signal by prioritizing a second real power current demand signal over a second reactive power current demand signal. Alternatively, the method also includes determining at least one of a second real power current demand signal and a second reactive power current demand signal by prioritizing the second reactive power current demand signal over the second real power current demand signal. The method further includes comparing at least one of the first real power current demand signal and first reactive power current demand signal to at least one electrical machine current limit signal.

Abstract: An exemplary embodiment includes a wind turbine system. The wind turbine system includes a wind turbine generator operable to supply wind turbine power to a utility system. A converter is coupled to the wind turbine generator and the utility system. The wind turbine system also includes a controller comprising an internal reference frame of the wind turbine generator, coupled to the converter, and configured for modulating flow of power through the converter in response to frequency disturbances or power swings of the utility system relative to the internal reference frame.

Abstract: A brushless exciter for a synchronous generator or motor generally includes a stator and a rotor rotatably disposed within the stator. The rotor has a field winding and a voltage rectifying bridge circuit connected in parallel to the field winding. A plurality of firing circuits are connected the voltage rectifying bridge circuit. The firing circuit is configured to fire a signal at an angle of less than 90° or at an angle greater than 90°. The voltage rectifying bridge circuit rectifies the AC voltage to excite or de-excite the field winding.

Abstract: A system and method of operating a wind farm, having multiple wind turbine generators, at high wind speeds is provided. Wind speeds at individual wind turbine generators are monitored and a signal is transmitted from the wind turbine generators to a wind farm control system based on the monitored wind speeds. Rate of change of collective power output of the wind farm is temporally monitored and is controlled by coordinating of operational states of the wind turbine generators based upon the signals transmitted by the one or more wind turbine generators, operating conditions of the wind turbine generators and the monitored rate of change of power output of the wind farm.

Abstract: A protection system and a protection method are provided for protecting a double fed induction generator and a gearbox during a grid fault. The protection system includes a plurality of controlled impedance devices. Each of the controlled impedance devices is coupled between a respective phase of a stator winding of the double fed induction generator and a respective phase of a grid side converter. The protection system also includes a controller configured for coupling and decoupling impedance in one or more of the plurality of controlled impedance devices in response to changes in at least one of a utility grid voltage and a utility grid current.