Abstract: According to one example, a system includes a second computing device that has one or more processors configured to receive encrypted data from a first computing device, the encrypted data being encrypted based on a first encryption key. The one or more processors are further configured to generate a second encryption key that matches the first encryption key, decrypt the encrypted data using the second encryption key, and transmit the data for use.

Abstract: A valve assembly is disclosed that has a valve housing including a first axial end, a cap, a second axial end, and an airflow pathway extending from the first axial end towards the second axial end. The cap is positioned towards the second axial end. The valve housing includes an environmental opening configured for fluid communication with an outside environment, an enclosure opening towards the first axial end configured for fluid communication with an interior of an enclosure, and a film having an expansion diameter disposed in the valve housing laterally across the airflow pathway. The cap has an inner lateral surface and a piercing protrusion (having a piercing tip) extending from the inner lateral surface towards the first axial end. An axial distance is defined between the film and the inner lateral surface. A ratio of the axial distance to the film expansion diameter is at least 0.14.

Abstract: The detecting a shadow is determined by a modeling of at least a portion of a wind turbine. First and second sensors are arranged relative to the model such that the first sensor detects a light and the second sensor detects a shadow during the conditions where the shadow would be produced.

Abstract: A system and method for regulating a voltage at a point of common coupling (35) (PCC) of a distributed energy resource farm (1) connected to an electrical power grid (37). The distributed energy resource farm includes a plurality of connected distributed energy resources (2, 3) each supplying a terminal voltage. The system includes a component (50) for measuring a PCC voltage at the PCC, and another component (39, 41) for determining a first value based on a relationship between a scheduled voltage at the PCC and the measured PCC voltage relative to a dead band voltage region (66). A further component (39, 41) regulates the voltage at the point of common coupling by controlling the terminal voltage of each one of the plurality of distributed energy resources in response to the relationship between the scheduled voltage and the measured voltage at the PCC.

Abstract: A wind turbine system (20, 70) is connected to an electrical grid (42) by an inverter (38) that provides turbine terminal voltage (Vt) support to the grid during a grid low voltage fault that is concurrent with a lack of real power production from the generator (30) by providing reactive power to the grid. A processor (46) controls the inverter to preserve a minimum voltage on a local DC bus (34) by stopping the reactive power output when the DC bus voltage drops to a threshold value (59) that is above a low bus voltage trip setpoint (56). An energy storage device (48) such as a battery may be connected to the DC bus to provide power that supports a prolonged ride-through capability during the grid fault.

Abstract: The detecting a shadow is determined by a modeling of at least a portion of a wind turbine. First and second sensors are arranged relative to the model such that the first sensor detects a light and the second sensor detects a shadow during the conditions where the shadow would be produced.

Abstract: This disclosure describes a scrolling graphical user interface element that displays, in real time or substantially real time, search requests that are received by a system. For example, when a query is received, details about the query are stored and subsequently used to generate a selectable item that is provided on the scrolling graphical user interface element. The scrollable graphical user interface is provided on a webpage and is updated with selectable items each time a new query is received. Thus, any user accessing the webpage can view, in real time or substantially real time, other queries that are being submitted by other users.

Abstract: A wind turbine system (20, 70) is connected to an electrical grid (42) by an inverter (38) that provides turbine terminal voltage (Vt) support to the grid during a grid low voltage fault that is concurrent with a lack of real power production from the generator (30) by providing reactive power to the grid. A processor (46) controls the inverter to preserve a minimum voltage on a local DC bus (34) by stopping the reactive power output when the DC bus voltage drops to a threshold value (59) that is above a low bus voltage trip setpoint (56). An energy storage device (48) such as a battery may be connected to the DC bus to provide power that supports a prolonged ride-through capability during the grid fault.

Abstract: Method and apparatus are provided for determining a grid condition, such as a weakened grid condition, and controlling a power plant, such as a wind or solar power plant, in a manner which is appropriate to the grid condition. The method includes measuring (14) output parameters of a generator, such as a wind turbine or PV generator. The measured output parameters include reactive power and voltage. The method further includes determining (16) a relationship between the measured output parameters of the generator. The relationship between the measured output parameters of the generator is indicative of a condition of a power grid to which the plant supplies power. The method allows controlling (18) the plant responsive to the relationship between the measured output parameters of the generator to avoid onset of oscillatory behavior, which could otherwise occur in the power plant in the presence of a weakened grid condition.

Abstract: A system and method for regulating a voltage at a point of common coupling (35) (PCC) of a distributed energy resource farm (1) connected to an electrical power grid (37). The distributed energy resource farm includes a plurality of connected distributed energy resources (2, 3) each supplying a terminal voltage. The system includes a component (50) for measuring a PCC voltage at the PCC, and another component (39, 41) for determining a first value based on a relationship between a scheduled voltage at the PCC and the measured PCC voltage relative to a dead band voltage region (66). A further component (39, 41) regulates the voltage at the point of common coupling by controlling the terminal voltage of each one of the plurality of distributed energy resources in response to the relationship between the scheduled voltage and the measured voltage at the PCC.

Abstract: A method and a controller for continuously operating a plurality of electric energy generating machines during a high voltage condition at a point of common coupling of the plurality of electric energy generating machines are provided herein. The method includes a) sensing a voltage level at the point of common coupling exceeding a permitted voltage level; b) curtailing an active power output of the plurality of electric energy generating machines such that a reactive capability of the plurality of electric energy generating machines is increased; c) establishing a set point of an electric quantity being present at the point of common coupling such that a reactive electric component providable by the electric energy generating machines is increased; and d) controlling an electric energy generating machine based on the set point of the electric quantity such that the high voltage condition at common coupling is at least partially remedied.

Abstract: A power generating device (2, 3) for supplying power to a power system (37). The power generating device includes a first component (87) for generating a first signal representing a frequency of a voltage on the power system, a power converter (90) for generating an output voltage, a second component (82) responsive to the first signal and to a second signal representing the output voltage, the second component producing an error signal representing a phase angle difference between the first and second signals, and the error signal being an input to the power converter for controlling the power converter to maintain the phase angle difference between the output voltage and the first signal.

Abstract: A method for compensating at least partially a frequency deviation in a grid is provided in which a grid frequency is determined and the grid frequency is applied to a grid frequency criterion. If the grid frequency meets the grid frequency criterion, a determination is made as to a set of wind turbines from a wind turbine power plant fleet based on the grid frequency criterion, and a command for a transient frequency response is transmitted to the set of wind turbines.

Abstract: A method of operating a wind park having a plurality of wind turbines is provided. The method includes determining a grid condition indicator indicative of the condition of a grid into which the wind park feeds; determining a first maximum power value of the wind park on the basis of the grid condition indicator; determining an operating margin on the basis of the grid condition indicator, for a grid condition indicator indicative of a weak grid; determining a second maximum power value on the basis of the operating margin; and curtailing the active power output of the wind park according to a maximum power value. A computer program product for carrying out the steps of such a method; an active power controller adapted for use in operating a wind turbine of a wind park; a wind turbine; and a wind park are also provided.

Abstract: A wind turbine (8) for controlling power oscillations on a grid of a power system (28). The wind turbine (8) comprises rotor blades (12) for turning by the wind, an electric generator (20) rotatably coupled to the rotor blades (12), a power converter (24) responsive to electricity generated by the electric generator (20), the power converter (24) for converting the generated electricity to a frequency and voltage suitable for supply to the power grid (28), and the power converter for regulating voltage on the grid supplemented by modulating real power for damping the power oscillations.

Abstract: A method of controlling a wind power plant, the wind power plant having a plurality of wind turbines and being connected to a power grid is provided. The method includes (a) detecting a grid frequency instability, (b) selecting a subset of wind turbines, (c) modifying a power reference for each wind turbine in the selected subset of wind turbines to respond to the grid frequency instability, and (d) applying the modified power references to the corresponding wind turbines in the selected subset of wind turbines. A wind power plant controller, a wind power plant, a computer program, and a computer program product are also provided.

Abstract: A wind turbine generator park (1) for supplying power to a power system (37), the park having an assigned first droop response characteristic for use in responding to an under-frequency occurrence on the power system (37). The park comprises a first comparator (108) for generating a first signal when the park is operating according to a curtailed condition, a second comparator (100) for indicating that a change in a frequency of a voltage or current on the power system (37) is greater than a first threshold value, and a controller (114) responsive to the first and second signals for controlling the park according to a second response characteristic causing the park (1) to supply an amount of power to the power system (37) greater than the power supplied according to the first droop response characteristic.

Abstract: Apparatus to provide arc flash protection regarding a wind turbine. In one embodiment, a wind turbine (10) includes a wind turbine generator (12) to generate an alternating current power. A transformer (14) has a high-voltage side (16) coupled to a load. A circuit breaker (18) is adapted to selectively reduce arc flash energy available to the wind turbine. The circuit breaker may be arranged to provide circuit interruption between the generator and a low-voltage side (20) of the transformer upon detection of a fault condition. The circuit breaker includes an arc flash protection mode (24) and a normal protection mode (22). In response to a sensed condition, a respective one of the modes may be automatically set so that the circuit breaker can perform the circuit interruption in accordance with the protection functionality of the set mode.

Abstract: Method and apparatus are provided for determining a grid condition, such as a weakened grid condition, and controlling a power plant, such as a wind or solar power plant, in a manner which is appropriate to the grid condition. The method includes measuring (14) output parameters of a generator, such as a wind turbine or PV generator. The measured output parameters include reactive power and voltage. The method further includes determining (16) a relationship between the measured output parameters of the generator. The relationship between the measured output parameters of the generator is indicative of a condition of a power grid to which the plant supplies power. The method allows controlling (18) the plant responsive to the relationship between the measured output parameters of the generator to avoid onset of oscillatory behavior, which could otherwise occur in the power plant in the presence of a weakened grid condition.

Abstract: Apparatus to provide arc flash protection regarding a wind turbine. In one embodiment, a wind turbine (10) includes a wind turbine generator (12) to generate an alternating current power. A transformer (14) has a high-voltage side (16) coupled to a load. A circuit breaker (18) is adapted to selectively reduce arc flash energy available to the wind turbine. The circuit breaker may be arranged to provide circuit interruption between the generator and a low-voltage side (20) of the transformer upon detection of a fault condition. The circuit breaker includes an arc flash protection mode (24) and a normal protection mode (22). In response to a sensed condition, a respective one of the modes may be automatically set so that the circuit breaker can perform the circuit interruption in accordance with the protection functionality of the set mode.