A turboexpander can operate as a microgrid electric generator for islanding operations. The turboexpander can recover energy lost during a pressure letdown sequence to generate electricity. Pressurized process gas can cause a turbine to rotate, thereby rotating a rotor within a stator of the turboexpander. A power electronics can include an islanding mode inverter to output an alternating current that comprises a frequency and an amplitude compatible with powering a load. The power electronics can include a battery that is charged by the turboexpander and can provide power for starting up the turboexpander. The power electrics can include a bidirectional inverter to send excess power from the turboexpander to a power grid and to receive power from the power grid for start-up.

A system of recycling power from flowing fluids, uses a fluid pump, e.g., a water pump or an air pump, driven from a power source to create a flow. A fluid movement recycling device, is located in the path of the fluid flow, such that the fluid flowing causes the fluid movement recycling device to rotate. A DC motor, receives the rotation from the fluid movement rotating device, and produces an output of DC power, which charges a battery that itself is used to drive the fluid pump.

Disclosed herein is a hydropower electric generator, in accordance with some embodiments. Accordingly, the hydropower electric generator may include a closed conduit. Further, the closed conduit may include a reservoir, a downward flow pipe, a horizontal pipe, an upward flow pipe. Further, the downward flow pipe may include a first turbine configured to intercept the downward flow of the water and generate rotational force. Further, the upward flow pipe may include an airlift assembly configured to receive compressed air into the upward flow pipe. Further, the upward flow pipe may include a second turbine configured to intercept an upward flow of the water and generate rotational force. Further, the hydropower electric generator may include an air pump configured to generate the compressed air based on electrical energy. Further, the hydropower electric generator may include an energy storage device.

A downhole power generation system is disclosed, which includes a turbine generator system. The turbine generator system includes a turbine, a generator coupled with the turbine and having an AC-DC rectifier, and an optimized power control unit. The turbine is driven by flow of a downhole fluid to rotate. The generator converts rotational energy from the turbine to electrical energy and outputting a direct current voltage. The turbine generator system is coupled to a load via the optimized power control unit. The optimized power control unit controls to regulate an output voltage of the generator and provides a regulated output voltage to the load so that the turbine generator system has an optimized power output. An optimized power control method for a downhole power generation system is also disclosed.

Provided is a method for controlling, by means of field-oriented closed-loop control, an active rectifier which is electrically connected to a stator of a generator of a wind turbine. The generator has a rotor which is mounted so as to be rotatable about the stator and comprises the steps of determining a mechanical position of the rotor with respect to the stator, predefining DC components of rotor-fixed d and q coordinates for at least one 3-phase stator current, determining an AC component for the q coordinate at least as a function of the mechanical position of the rotor, modulating the determined AC component of the q coordinate onto the predefined DC component of the q coordinate, so that a modulated q coordinate is produced which has a DC component and an AC component, and controlling the active rectifier at least as a function of the modulated q coordinate and preferably as a function of the d coordinate.

An apparatus to produce electricity from several renewable energy sources. The device collects wind into a duct, adds energy to the collected wind by adding heat from the sun and building exhaust, and produces electricity via a generator therefrom. The wind capture unit includes a plurality of faces that face all compass directions to avoid having to adjust the device upon shifts in wind direction and speed. The duct includes a tapered portion that serves to increase a speed of inflow air prior to impinging upon a turbofan generator. The device can be mounted on a top of a building and receive building exhaust while supplying the building with electricity. The result is a higher efficiency device with pleasing aesthetics.

Disclosed herein is a hydropower electric generator, in accordance with some embodiments. Accordingly, the hydropower electric generator may include a closed conduit. Further, the closed conduit may include a reservoir, a downward flow pipe, a horizontal pipe, an upward flow pipe. Further, the downward flow pipe may include a first turbine configured to intercept the downward flow of the water and generate rotational force. Further, the upward flow pipe may include an airlift assembly configured to receive compressed air into the upward flow pipe. Further, the upward flow pipe may include a second turbine configured to intercept an upward flow of the water and generate rotational force. Further, the hydropower electric generator may include an air pump configured to generate the compressed air based on electrical energy. Further, the hydropower electric generator may include an energy storage device.

A wind turbine (10) is disclosed having a hub (14) with electrical power therein and at least one blade (20) attached to the hub. The blade (20) has a blade root (21), a blade tip (26) and a down-wire (30) for the conduction of lightning current to the ground. The wind turbine (10) further has a blade electrical system (99) that takes electrical power from the hub (14) and transmits electrical power into the blade (20) to at least one area located between the blade root (21) and the blade tip (26). The blade electrical system (99) if formed by a power-transfer unit (100) having a power-driver unit (110), a power-conditioner unit (130) and a dielectric (120) separating the power-driver unit (110) and the power-conditioner unit (130). The power-driver unit (110) receives electrical power from the hub (14) and transmit the electrical power through the dielectric (120) to the power-conditioner unit (130). An electrical-power bus (200) is electrically attached to the power-conditioner unit (130) and extends into the blade (20). At least one powered unit (300) is provided which is electrically connected to, and electrically powered by, the electrical-power bus (200).

The application relates to a battery storage and a wind turbine including a generator for generation of an electric current. An electric flow path configured for conducting the electric current to an electric grid via a power converter, the power converter. A battery storage electrically connected to the electric flow path, the battery storage including a plurality of battery cells, each battery cell including at least one battery element and at least two semiconductor switches. Wherein a controller is configured for selectively controlling the voltage over the battery storage by controlling the status of the at least two semiconductor switches of a plurality of the battery cells and thereby if a current path through the battery storage is bypassing the at least one battery element or passing through the at least one battery element of one or more of the plurality of battery cells.

The present invention relates to a wind turbine with an electrical machine wherein said electrical machine comprises a stator (702) with one or more electrical winding(s) (704), said electrical winding(s) being arranged to be connected to an electrical grid (760) by at least one cable (740) with at least one phase conductor (746), the at least one cable (740) comprises at least one return path (744) to conduct leakage currents, and at least one electrical shield (745), the stator being electrically isolated from a stator housing (701). The invention also relates to a method for minimizing stray currents in an electrical machine in a wind turbine.