A method for operating an asynchronous inverter-based resource connected to a power grid as a virtual synchronous machine to provide grid-forming control thereof includes receiving a frequency reference command and/or a voltage reference command. The method also includes determining at least one power reference signal for the inverter-based resource based on the frequency reference command and/or the voltage reference command. Further, the method includes generating at least one current vector using the power reference signal(s). Moreover, the method includes determining one or more voltage control commands for the inverter-based resource using the at least one current vector. In addition, the method includes controlling the inverter-based resource based on the one or more voltage control commands such that the inverter-based resource actively participates in controlling at least one of voltage and frequency at a point of interconnection between the inverter-based resource and the power grid in a closed loop manner.

A method and system of subsynchronous oscillations and interactions damping integrated in in a rotor converter based on an adaptive state feedback controller with two spinning vectors, and a Kalman filter whose parameters are optimized by minimizing maximum sensitivity under a constraint of positive damping for a plurality of sensible scenarios is provided. The damping signal generated by the damping module is applied either to a power proportional integer controller or to a current proportional integer controller.

Wind farms and methods for operating wind farms are provided. A wind farm includes a plurality of wind turbine generators. A method includes determining an available reactive power value for each of the plurality of wind turbine generators. The method further includes distributing an individual reactive power command to each of the plurality of wind turbine generators. The individual reactive power command is individually tailored to each wind turbine generator of the plurality of wind turbine generators based on the available reactive power value for that wind turbine generator.

Wind farms and methods for operating wind farms are provided. A wind farm includes a plurality of wind turbine generators. A method includes determining an available reactive power value for each of the plurality of wind turbine generators. The method further includes distributing an individual reactive power command to each of the plurality of wind turbine generators. The individual reactive power command is individually tailored to each wind turbine generator of the plurality of wind turbine generators based on the available reactive power value for that wind turbine generator.

The present disclosure is directed to a system and method for optimizing operation of a wind turbine. The method includes providing a voltage regulator between a power grid and the wind turbine. The voltage regulator is configured to control at least one voltage condition of the wind turbine. Another step includes monitoring, via one or more sensors, at least one operating condition and at least one voltage condition of the wind turbine. The method also includes comparing, via a controller, at least one of the operating condition or the voltage condition with a predetermined threshold to determine a margin-to-threshold ratio. Thus, a further step includes controlling the voltage regulator based on the comparison so as to maximize the margin-to-threshold ratio.

An apparatus including a pneumatic system; an energy harvesting unit configured to generate electrical energy from a compressed gas in the pneumatic system; a battery connected to the energy harvesting unit; a sensor disposed to detect a first parameter regarding operation of the energy harvesting unit; and a controller connected to the sensor and the energy harvesting unit. The sensor and the controller are powered by the energy harvesting unit. The controller is configured to control the energy harvesting unit and to process measurements for the first parameter detected by the sensor. The controller is further programmed with a learning system configured to diagnose an operational condition of the energy harvesting unit based on the measurements for the first parameter, and to issue a command to the controller based on the operational condition.

An engine starter unit for starting an engine, includes a starter, a first controller, and a prohibiting means. The starter includes a motor generating a rotary force and a pinion transmitting the rotary force generated by the motor to the engine, the starter cranking the engine up to an engine speed of 450 rpm or more in a drive ON state. The first controller turns the starter into the drive ON state to make the starter start cranking in response to an ON operation of an ignition switch by a user. The prohibiting means prohibits the starter from being turned into the drive ON state again in response to another ON operation of the ignition switch for a prohibition duration after the first ON operation by the user.

The invention relates to a control system for a wind turbine generator, WTG. The control system defines reactive limits for a reactive power reference for the WTG. The reactive limits are defined as a function of a physical parameter, e.g. the output voltage of the WTG. In case the reactive power reference exceeds the predefined limits, the reactive power reference is limited. By limiting the reactive power reference output voltages which exceed certain output voltage limits may be avoided and, thereby, a disconnection of the WTG from the grid may be avoided.

The object of the invention is a method and an apparatus in an electric propulsion arrangement of a sailing vessel, wherein the sailing vessel has a traction device provided with an electric motor and with a propeller mechanism, the electric motor of traction device is arranged to be used, if necessary, in forward drive and reverse drive as well as during sailing as a generator for charging the accumulators of the sailing vessel. The propeller mechanism comprises a propeller hub with blades, a hollow propeller shaft fixed at its first end to the propeller hub, a shaft controlling the pitch angles of the propeller blades, said control shaft rotating inside the propeller shaft, and a servomotor rotating the control shaft. The servomotor is fixed to the second end of the propeller shaft to be rotatable along with the propeller shaft.

A generation and distribution system includes an adjustable-speed prime mover and a doubly-fed asynchronous alternating-current (AC) generator driven by the prime mover and having a first poly-phase circuit, e.g., a stator, and a second poly-phase circuit, e.g., a rotor. The system further includes a first AC bus electrically coupled to the first poly-phase circuit configured to deliver AC power at a first AC voltage to multiple loads, and a second AC bus connected to the second poly-phase circuit configured to deliver AC power at a second AC voltage to another group of loads, the second AC voltage being lower than the first. The system includes a poly-phase transformer having first windings electrically coupled to the first AC bus and having second windings electrically coupled to the second AC bus, and a poly-phase AC-to-AC electronic converter circuit electrically coupled between the second poly-phase circuit and the second AC bus.