Integration of Power Grids with Wind Turbines

Self-regulating wind turbine generator that can adjust output voltage without mechanical components like blade pitch control or yaw systems. The generator has a rotor spinning with the wind turbine and a stator that can move inside the rotor's magnetic field. An actuator moves the stator closer to the rotor to increase voltage below a threshold and farther away to limit voltage above the threshold. This self-regulation allows maximum voltage extraction without overloading the system in high winds.

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Control method for wind turbines configured as virtual synchronous machines (VSMs) to improve grid stability and reduce mechanical loads after faults. The method involves controlling the wind turbine's power output based on the synchronous machine angle, using high-pass filtered rotational speed to determine damping power. It also uses comparisons of DC link voltage and grid power to determine chopper power. This allows the wind turbine to provide grid-forming properties similar to a synchronous generator while avoiding power oscillations and excessive mechanical loads after faults.

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Controlling wind turbine power output during frequency events on the grid to avoid the "wind-up" issue where the set point from the grid controller exceeds the turbine's output limits. During grid frequency deviations, the turbine's active power reference is set to the limit if the calculated reference is outside it. After the deviation, the reference ramps back to baseline instead of waiting for the set point to reach the limit. This ensures the turbine's output matches the reference during deviations and ramps immediately after, avoiding delays.

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A wind farm design with onsite hydrogen production and export to mitigate power fluctuations and avoid long-distance transmission costs. The wind turbines have electrolysis units to generate hydrogen using excess wind power. The hydrogen is exported via a shared above-sea-level manifold rather than subsea connections. This allows easier maintenance and prevents corrosion compared to underwater connections. The manifold connects the turbine hydrogen outputs to a common pipeline for transporting the hydrogen produced by the wind farm. This eliminates the need for individual subsea connections from each turbine. The manifold can be housed in a container or installed at the turbine platform or tower.

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Wind turbine with integrated harmonic filters to reduce harmonic distortion in wind farm electrical grids. The filters are mounted inside the turbine tower instead of at the substation. This eliminates the need for large external filters at the farm level, reducing cost and footprint. The filters connect to the high voltage side of the main transformer inside the turbine. When a turbine is disconnected from the grid, the filter remains connected to dampen harmonics on the remaining turbines.

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Optimizing power generation in a wind farm by dynamically adjusting the operating parameters of individual wind turbines based on local wind shear conditions. The method involves measuring or predicting the vertical wind shear profile above the wind farm. This profile is then used to determine optimal adjustments to turbine settings like blade pitch, rotor speed, and yaw angle. These adjustments are made in real-time to optimize overall farm power production considering the non-standard wind shear profile and turbine interactions.

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Superconducting direct drive generator for wind turbines that can generate higher electrical power than conventional generators while reducing weight and size for easier installation on tall towers. The generator has a stationary coil wound around a composite torque tube and a rotating armature. The torque tube supports the stationary coil and prevents rotational motion. This allows a compact, lightweight generator that can be mounted directly on the wind turbine hub without gearboxes or heavy rotor masses. The superconducting coils provide high torque density. The composite torque tube reduces weight compared to solid steel.

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A pipeline power generation system that uses compressed air storage and multi-stage wind turbines in a sealed pipe to reduce the cost of peak shaving power compared to conventional methods. The system stores excess low-demand electricity in compressed air, then releases it through a sealed pipe with multiple wind turbines of decreasing size. The high-speed compressed air flows through the turbines, converting kinetic energy into electricity as wind speed decreases. Mixing atomized water with the air further improves generation efficiency. Multiple parallel systems can be connected to increase total peak power capacity.

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Operating wind turbines to charge auxiliary power sources during low wind conditions instead of idling the main generator. When certain conditions are met, the turbine blades are pitched to a fixed angle for idling. If wind speed exceeds a threshold, the rotor spins to charge the auxiliary power sources without generating main power. This avoids wasting power keeping the main generator running at low speeds.

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A stability evaluation method and system for direct-drive wind turbine generators that allows online assessment and parameter adjustment to improve stability of the system. The method involves calculating the energy gradient at the wind turbine terminal using voltage, current, and angle measurements. A negative energy gradient indicates instability. The gradient is influenced by factors like PLL parameters, wind turbine current levels, and transmission line resistance. By understanding these relationships, the method proposes adjustments to critical parameters like PLL gains and wind turbine current limits to improve stability.

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A modular multi-turbine wind power system that improves efficiency and durability compared to single-turbine systems. The system uses a toroidal support structure with concave and convex sections. A turbine travels around the concave section, surrounded by baffles that adjust the flow of air. This allows each turbine to rotate to the most efficient position relative to the wind. A control system optimizes turbine positioning based on wind data. The toroidal shape and baffles also reduce noise and damage risks. The system can switch between power generation and resistance modes based on wind speed.

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Method to improve reactive power capability of wind turbines with doubly-fed induction generators (DFIGs) by intelligently managing generator speed in low wind conditions. The method involves transitioning to a secondary operational mode when certain parameters like rotor speed drop below thresholds. In this mode, the turbine increases generator speed at the expense of active power production. This allows maintaining reactive power capability in low wind conditions where DFIGs have limited reactive power capacity. The mode is selectable by command. The method balances maximizing active power versus reactive power capability.

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A hybrid wind power system that uses vertical axis wind turbines to compress air for a gas turbine power generation cycle. The system avoids the limitations of large horizontal axis wind turbines by using vertical axis turbines that can handle variable winds better. The vertical axis turbines directly drive compressors to compress air, which is then expanded through a gas turbine to generate electricity. This allows on-demand power generation near loads instead of relying on remote wind farms. The hybrid system also includes intercooling between compression stages to achieve higher pressure ratios for more power extraction.

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A system for generating high frequency switching signals to enable higher voltage output from power converters in power generation systems like wind turbines without the need for bulky transformers. The system uses a control device with multiplexing, integration, modulation, and generation stages to convert a low frequency PWM signal into a higher frequency PWM signal. This allows operating the converters at higher switching frequencies to directly couple the converter output to the stator voltage instead of using a separate transformer.

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Controlling a wind turbine during grid faults to allow ride-through capability while preventing excessive mechanical loads. The technique involves dynamically adjusting the drivetrain damping settings based on the number of grid faults. For the first fault, the damping is tuned for power performance. For subsequent faults, the damping is adjusted to prioritize reducing mechanical loads. This allows the turbine to ride through multiple faults without tripping, while preventing excessive loads during prolonged fault sequences.

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Control module for a wind power converter that emulates the behavior of a synchronous generator to improve grid stability. The converter is controlled to behave like a synchronous machine even when connected to the grid. The module calculates a power change based on the converter output power and sets a new power target accordingly. This compensates for network errors and maintains stability. It allows converter-based generators to operate like synchronous machines without losing converter benefits. The module has a power calculation circuit and a setpoint adjustment circuit.

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Method and apparatus for controlling renewable energy generation to provide constant frequency power at variable loads. It uses a voltage regulator with feedback from the load and feedforward from the renewable source to maintain output frequency. This allows maximizing baseload power from fluctuating renewables like wind and water. The regulator replaces mechanical speed converters in motor equivalent generators. It replaces variable voltage transformers in MG sets. The regulator connects between the renewable source and load, using a servo motor to adjust voltage for constant frequency.

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A method to avoid tripping of wind turbines caused by excessive currents in the power electronic converter. The method involves temporarily increasing the generator speed above nominal if certain operational parameters indicate potential converter tripping. This reduces converter currents and avoids tripping. The generator speed is then lowered back to nominal once the parameters indicate converter operation is safe again.

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Fast frequency response method for wind turbines to improve grid stability by utilizing inertial energy stored in the turbine rotor to quickly arrest frequency drops after grid disturbances. The method involves overproducing power from the turbine in response to grid frequency changes, which slows the rotor. A dynamic adaptive gain adjusts the overproduction level based on wind speed and penetration to optimize grid support. This prevents large frequency overshoots and dips compared to fixed gains.

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Wind turbines with integrated harmonic filters to reduce harmonics in wind farm electrical grids without needing a separate filter at the substation. The filters are placed inside the turbine's support structure and connected to the high voltage side of the main transformer. This allows damping harmonics in the medium voltage lines of the wind farm grid. The turbine generator can be disconnected during grid faults while the filter remains connected to continue damping.

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