741 results about "Flywheel energy storage" patented technology

Featured are methods for regulating the AC frequency of the electrical power be supplied on an electrical distribution system or grid. Such a method includes electrically coupling an energy storage sub-system to the electrical distribution network, where the energy storage sub-system includes one or more flywheel energy storage systems. Also featured as devices, systems and apparatuses embodying such methodologies or for use in implementing such methodologies of the present invention.

A low inductance electrical machine which may be used as an alternator or motor with low armature inductance is disclosed. Arrangements of complementary armature windings are presented in which the fluxes induced by currents in the armature windings effectively cancel leading to low magnetic energy storage within the machine. This leads to low net flux levels, low core losses, low inductance and reduced tendency toward magnetic saturation. Separately excited field arrangements are disclosed that allow rotor motion to effect brushless alternator or brushless motor operation. An exemplary geometry includes a stator including two toroidal rings and a concentric field coil together with a rotor structure separated from the stator by four air gaps. An alternate embodiment allows for counter-rotation of two rotor elements for use as a flywheel energy storage system in which the external gyroscopic effects cancel.

Featured are methods for regulating the AC frequency of the electrical power be supplied on an electrical distribution system or grid. Such a method includes electrically coupling an energy storage sub-system to the electrical distribution network, where the energy storage sub-system includes one or more flywheel energy storage systems. Also featured as devices, systems and apparatuses embodying such methodologies or for use in implementing such methodologies of the present invention.

A flywheel energy storage system (10) includes a vacuum enclosure (18) having a flywheel (12), motor / generator (14), and a shaft (16) enclosed within. The flywheel and motor / generator combination are designed to minimize bearing loads and thus increase system life, reliability and safety.

The invention discloses a method for outputting active power by using a smoothing permanent-magnet direct-driving wind power generating system of a direct-current-side flywheel energy storage unit. The method comprises the following steps of: controlling a motor-side converter; controlling a grid-side converter; and controlling an energy-storage-unit-side converter. By cooperated control of the motor-side converter, the grid-side converter and the energy-storage-unit-side converter, a wind power generator set can generate relatively-smoothed active output in the situation of change of a wind speed, and operating requirements of frequency modulation and voltage regulation of the system are met. The method has the advantages that: 1, based on the requirement of power smoothing control, maximum wind energy tracking control is realized; and 2, the network-side active power is smoothed, the quality of electric energy is improved, and the grid-connected operating characteristic of the wind power generating system is improved.

The invention provides a method for micro-grid system coordinated control based on multi-element composite energy storage. The method includes the steps that a flywheel energy storage unit is additionally arranged so that output fluctuation of voltage can be restrained; when a micro-grid system is in grid-connected operation, a battery energy storage unit and the flywheel energy storage unit restrain output fluctuation of a distributed generation unit; when the micro-grid system is in off-grid operation, the battery energy storage unit and a diesel generator alternately serve as a main power source of the micro-grid system; when grid-connected operation and off-grid operation of the micro-grid system are switched, the flywheel energy storage unit and the diesel generator provide power support. Through the method, the use rate of renewable energy sources is improved, optimal operation of power grids is achieved, instant high-power fluctuation and long time scale fluctuation of photovoltaic output are restrained, each distributed generation device is controlled in a coordinated mode, and timely, accurate and rapid coordination action of the devices can be guaranteed.

The invention relates to a flywheel energy storage device, in particular to a flywheel battery with a rapid charging and discharging function. The flywheel battery comprises a flywheel device and a driving device which drives the flywheel to rotate. The flywheel device comprises a flywheel, a flywheel rotating shaft and magnetic suspension bearings at the two ends of the flywheel rotating shaft. The periphery of the flywheel device is provided with a vacuum enclosed hood which is in interference fit with the magnetic suspension bearings. The flywheel is made from a magnetic material or internal magnets are fixedly arranged on the flywheel. The driving device comprises a transmission shaft and a rotor. One end of the transmission shaft is fixedly connected with the rotor, and the other end of the transmission shaft is connected with a motor or an engine. The rotor is made from the magnetic material or external magnets are arranged on the rotor. A gap is reserved between the rotor of the driving device and the flywheel device. The axis of the rotor is parallel to or overlapped with that of the flywheel rotating shaft. The flywheel and the rotor drive each other through a magnetic force. By the flywheel battery, energy storage capacity can be improved and service life can be prolonged; and the flywheel battery is convenient to produce in batches, maintain and service.

Several embodiments of an uninterruptible power supply (UPS) system, which system provides highly reliable output power to a load using a slip-ring induction machine and a flywheel combination, are disclosed as well as methods relating thereto. In a preferred embodiment, the UPS system comprises a back-up power source, e.g., an engine and generator, and a slip-ring, or wound-rotor, induction motor and flywheel combination, which are in parallel to a primary power source, e.g., a utility grid. During normal operation of the UPS, the primary power source supplies alternating current and voltage to the load and the UPS compensates for voltage drop across the isolating inductor. Moreover, the primary power source keeps the slip-ring induction machine and flywheel in an excited state, i.e., the rotor of the slip-ring induction machine, the shaft of which is shared by the flywheel, is excited above normal synchronous speed. When the primary power source fails, the flywheel, which is rotating at super-synchronous speed and storing kinetic energy, drives the rotor of the slip-ring induction machine and generates, i.e., induces current in the stator. Accordingly, the flywheel and slip-ring induction machine combination provides instantaneous, short term power to the load until the back-up power source has powered up and been brought on line.

The invention relates to a flywheel array energy storage system with flywheel energy storage units connected in parallel, which consists of a public direct current bus, a grid-connected static switch, a brake resistor, a flywheel array controller and at least two or more flywheel energy storage units and unit controllers thereof, wherein the internal structures and parameter features of the flywheel energy storage units are identical. Each flywheel energy storage unit is connected into the public direct current bus in a current source mode, and the number of the connected units can be increased and decreased casually. A master-slave control mode is adopted in the flywheel array energy storage system disclosed by the invention, power needed for maintaining direct current power grid power balance is computed by the flywheel array controller used as a master controller, and the power is distributed to each flywheel energy storage unit controller by a coordination control algorithm; and a bi-directional power conversion circuit and a permanent magnet synchronous motor are controlled by the unit controller used as a slave controller according to the obtained power instruction in a flywheel energy storage unit control method to absorb or release power to a direct current power grid.

The invention discloses a flywheel energy storage device adopting a bearingless switched reluctance motor. A permanent magnetic unloading bearing, a bearingless switched reluctance motor, a flywheel rotor and a mixed magnetic bearing are sequentially sleeved between the upper end and the lower end of a flywheel rotating shaft, wherein the permanent magnetic unloading flywheel carries the axial weight of the flywheel rotating shaft; the mixed magnetic bearing on the lower end overcomes the residual weight and the dynamic load of the flywheel rotating shaft, so that the flywheel rotating shaft is guaranteed to be stably suspended in the axial direction, simultaneously two-degree-of-freedom suspension bearing in the radial direction is provided for the flywheel rotating shaft, and the other two-degree-of-freedom suspension and electric function / power generation function in the axial direction are completed by the bearingless switched reluctance motor; and by adopting the high-speed electromotion / power generation running advantage and the self-suspension function of the bearingless switched reluctance motor, the strong unloading characteristic and the controllable suspension characteristic of the permanent magnetic unloading bearing and the mixed magnetic bearing are reasonably combined, so that the five-degree-of-freedom suspension of a flywheel with low loss and high reliability is realized, the running speed of the flywheel is improved, and the system power consumption and the size are reduced.

The present invention discloses a fluid-free mesh bearing damper, e.g., for a flywheel energy storage device. The disclosed mesh bearing damper is uniquely suitable for use in combination with flywheel assemblies, which typically are evacuated by one or more pumps to create a vacuum to substantially minimize energy loss due to air friction, because, among others, the disclosed bearing damper does not use fluids, e.g., pressurized oil, that may affect deleteriously the operation of the pumps. Moreover, the disclosed bearing damper damps vibrations, i.e., reduces the amplitude of the vibrations, induced by the rotating shaft, deflection of the shaft, and / or by the misalignment, or eccentricity, of the shaft; substantially lowers the load on the bearings, which enhances the life of the bearings and facilitates magnetic levitation; and transfers heat away from the bearings, which, further, enhances the life of the bearings. The disclosed bearing damper comprises at least one, e.g., copper, aluminum, carbon fiber, etc., circular mesh disk, which is in tight interference fit with the shaft bearing at the disk's inner periphery.

The invention discloses a cooling system of a flywheel energy storage device. The flywheel energy storage device consists of a shell and an internal disc-type motor, wherein the shell has a vacuum sealing structure; an upper oil cavity and a lower oil cavity are respectively arranged at the upper part and lower part of the shell; the shell internally comprises at least one set of flywheel; a center shaft of each flywheel is a hollow mandrel, and an axle hole is formed in the center of the center shaft and is communicated with the upper oil cavity and the lower oil cavity; an oil tank is arranged outside the shell; the oil tank is communicated with the upper oil cavity by an upper oil pipe and is communicated with the lower oil cavity by an oil return pipe; the oil return pipe is provided with a third valve, an oil pump and a radiator. The cooling system can be used for cooling a rotor by the axle hole, so that a great deal of heat of the rotor which rotates at a high speed can be taken away in time, and safe and stable operation of the flywheel energy storage device is guaranteed. An upper bearing, a lower bearing and a stator disc are cooled in time by part of cooling oil, and the bearings can be lubricated, so that the reliable work of key parts can be guaranteed, and the defects of cavitation and the like of a pump caused by low pressure can be avoided.

The invention provides a control method of a cell energy storage system inhibiting renewable energy output power fluctuation. The control method is characterized in that: based on a low pass filtering principle, through a first order Butterworth filter, a renewable energy output power value is subjected to filtering, a renewable energy output power object value is obtained, by utilizing charge and discharge control of the cell energy storage system, a difference between the renewable energy output power object value and a renewable energy output power measured value is compensated, and a purpose of inhibiting the renewable energy output power fluctuation is achieved. According to the invention, based on a basic filtering principle, by utilizing a good renewable energy output power inhibition effect and adding of an SOC (state of charge) feedback link, over charge and over discharge of a cell are avoided, innovation is carried out, when adding the SOC feedback link, through adjusting a size of a filtering time constant, an output power of the energy storage system is changed indirectly, thus when inhibiting the inhibiting the renewable energy output power fluctuation, the over charge and over discharge of the cell are effectively avoided, stable operation of the cell energy storage system is maintained, and a service life of the cell is prolonged.

The invention discloses a flywheel energy storage type secondary flow regulation coupled system, which relates to a closed loop hydraulic control system, and the invention solves the problems of high power density, low energy density and high cost existing in the existing secondary regulation hydrostatic transmission system which adopts a hydraulic accumulator to store energy. Two output shafts of a double-shaft motor in the system are respectively connected with a drive shaft of the flywheel and a transmission shaft of a hydraulic pump or a motor, and a variable cylinder regulates the working position of a sloping plate of the hydraulic pump or the motor under the control of an electro-hydraulic control valve. An upper limit sensor and a lower limit sensor are respectively fixed at the side face of a piston rod of a hydraulic cylinder to measure the position of the piston rod, and signal output ends of the upper limit sensor and the lower limit sensor are respectively connected with a signal output end of a controller. A control signal output end of the controller is connected with the control signal output end of the electro-hydraulic control valve, and the invention is suitable for industries of oil, mine and engineering plant, etc., especially for the system of frequent reciprocating motion and frequent start-stop.

Several embodiments of an uninterruptible power supply (UPS) system, which system provides highly reliable output power to a load using a slip-ring induction machine and a flywheel combination, are disclosed as well as methods relating thereto. In a preferred embodiment, the UPS system comprises a back-up power source, e.g., an engine and generator, and a slip-ring, or wound-rotor, induction motor and flywheel combination, which are in parallel to a primary power source, e.g., a utility grid. During normal operation of the UPS, the primary power source supplies alternating current and voltage to the load and the UPS compensates for voltage drop across the isolating inductor. Moreover, the primary power source keeps the slip-ring induction machine and flywheel in an excited state, i.e., the rotor of the slip-ring induction machine, the shaft of which is shared by the flywheel, is excited above normal synchronous speed. When the primary power source fails, the flywheel, which is rotating at super-synchronous speed and storing kinetic energy, drives the rotor of the slip-ring induction machine and generates, i.e., induces current in the stator. Accordingly, the flywheel and slip-ring induction machine combination provides instantaneous, short term power to the load until the back-up power source has powered up and been brought on line.

The invention relates to a low loss permanent magnet biased axial radial magnetic bearing, which belongs to a mixed magnetic bearing, which comprises an axial stator (1), an axial control winding (2), a radial magnetizing ring permanent magnet (7), a radial stator (3), a radial control winding (4) and a rotor (5) which is sleeved with an iron core (6). The low loss permanent magnet biased axial radial magnetic bearing uses the radial magnetizing ring permanent magnet to build a static bias magnetic field, a closed magnetic circuit is formed through an external axial pole core, a rotor iron core and a radial stator, and the axial control winding produces a controlling flux and a bias flux which are stacked to control axial suspension. A control winding is surrounded on a radial stator of a four-tooth two-antipode structure which is not retained gaps between magnetic poles, the windings on the two corresponding teeth are connected in series, and the superposition of the controlling flux and the bias flux are produced to achieve radial two freedom suspension. The structure is simple, the critical speed is high, the power consumption is low, and the low loss permanent magnet biased axial radial magnetic bearing has wide application prospect in high speed application fields which are flywheel energy storage, air conditioning compressors and turbomolecular pumps and the like.

Energy storage device comprising a flywheel a stator arrangement and a housing.The flywheel, rotatably mounted around a rotation axis, comprises a shaft, a plurality of adjacent magnetic plates with magnetic poles, two kinetic plates, sandwiching the magnetic plates. The magnetic plates and kinetic plates are rotationally rigid with said shaft.The stator arrangement comprises a plurality of induction coils cooperating with the magnetic poles.

The invention discloses a flywheel energy storing device with a permanent magnet bearing and a thrust bearing which comprises an upper shaft, a lower shaft, a flywheel body, a permanent magnet bearing, a motor, a bearing seat, a damper and a container, wherein the bottom of the lower shaft is provided with a ball head; the ball head is positioned in a groove at the top of the bearing; a damper stator is embedded in a ring groove of an upper soft magnetic ring; a damper rotor is embedded in a ring groove at the upper part of the flywheel body, and the upper end surface of a rotor outer insulative magnetic ring is opposite to the lower end surface of a stator outer permanent magnetic ring; the upper end surface of a rotor outer permanent magnetic ring is opposite to the lower end surface of a stator middle insulative magnetic ring; the upper end surface of a rotor middle insulative magnetic ring is opposite to the lower end surface of a stator middle permanent magnetic ring; the upper end surface of the rotor inner permanent magnetic ring is opposite to the lower end surface of a stator inner permanent magnetic ring; and the upper end surface of the rotor inner permanent magnetic ring is opposite to the low end surface of the stator inner permanent magnetic ring. According to the flywheel energy storing device of the structure, the flywheel body can pass through the low order critical speed of rotation, and the whole flywheel energy storing device has favorable dynamic characteristics.

An axial stabilizer for the rotor of a magnetic bearing provides external control of stiffness through switching in external inductances. External control also allows the stabilizer to become a part of a passive / active magnetic bearing system that requires no external source of power and no position sensor. Stabilizers for displacements transverse to the axis of rotation are provided that require only a single cylindrical Halbach array in its operation, and thus are especially suited for use in high rotation speed applications, such as flywheel energy storage systems. The elimination of the need of an inner cylindrical array solves the difficult mechanical problem of supplying support against centrifugal forces for the magnets of that array. Compensation is provided for the temperature variation of the strength of the magnetic fields of the permanent magnets in the levitating magnet arrays.

The invention provides a flywheel energy storage accelerating carrier-based aircraft ejector and an ejection method. The structure of the ejector is composed of a power machine, a clutch, a flywheel, a transmission shaft, a traction winch and a reel-off winch, wherein the traction winch and the flywheel are arranged on the transmission shaft, and the flywheel and the transmission shaft are fixed together; the traction winch is connected with the transmission shaft through a bearing; a flywheel clutch is arranged between the flywheel and the traction winch; the transmission shaft is fixed by a bearing bracket; and the end part of the transmission shaft is connected with the power machine through a motor clutch. Compared with the prior art, the flywheel energy storage accelerating carrier-based aircraft ejector has reasonable design, simple structure, safety, reliability, small volume, high automaticity, convenient use, easy maintenance and the like, and has favorable popularization and use value.

A high voltage DC power distribution system that eliminates static switches and batteries. Flywheel energy storage devices and extremely reliable, high power DC / DC converters provide at a lower cost, more reliable, noise and harmonic free, critical electrical power directly at equipment racks at 48 VDC, 24 VDC, 6 VDC, 2 VDC, or any other desired DC voltage level.

The invention relates to a magnetic suspension flywheel energy storage device with a suspension / energy storage integrated flywheel, which comprises a shell, a permanent magnet type radial magnetic suspension bearing A stator, a permanent magnet type radial magnetic suspension bearing B stator, an electromagnetic permanent-magnet hybrid type axial magnetic suspension bearing stator and a motor / generator stator, wherein the permanent magnet type radial magnetic suspension bearing A stator and the permanent magnet type radial magnetic suspension bearing B stator are respectively positioned on the bottom and top of the shell; the electromagnetic permanent-magnet hybrid type axial magnetic suspension bearing stator and the motor / generator stator are installed on the inner wall of the shell; the device also comprises a permanent magnet type radial magnetic suspension bearing B rotor, a motor / generator rotor, a suspension / energy storage integrated flywheel A, a suspension / energy storage integrated flywheel B and a permanent magnet type radial magnetic suspension bearing A rotor which are arranged on a main shaft from top to bottom; the suspension / energy storage integrated flywheel B is positioned between the permanent magnet type radial magnetic suspension bearing A stator and the electromagnetic permanent-magnet hybrid type axial magnetic suspension bearing stator; and the suspension / energy storage integrated flywheel A is arranged between the motor / generator stator and the electromagnetic permanent-magnet hybrid type axial magnetic suspension bearing stator. The invention has the advantages of compact structure, small size, light weight, high efficiency and high energy density.

The invention relates to an energy recovery device used for a variable frequency system of a motor, in particular to an energy recovery device for carrying out dynamic equilibrium on DC (direct current) bus voltage of the variable frequency system and an energy recovery method thereof. The energy recovery device comprises a bi-directional DC / AC (alternating current) converter and a vacuum energy storage flywheel, wherein the bi-directional DC / AC converter is respectively connected with a DC bus of the variable frequency system and the vacuum energy storage flywheel; the bi-directional DC / AC converter comprises a central processing unit, a rectification / inversion unit and periphery auxiliary circuits; and the central processing unit comprises a microprocessor, a circuit for acquiring the DC bus voltage and a circuit for acquiring rotating speed of the vacuum energy storage flywheel. The energy recovery method is characterized in that when the difference between the DC bus voltage of the variable frequency system and a preset upper limit threshold is monitored by the central processing unit, the rotating speed of the vacuum energy storage flywheel is monitored at the same time, so that whether a DC-AC flow is started or not is determined so as to enable the vacuum energy storage flywheel to absorb or release energy from the DC bus of the variable frequency system.

Methods and apparatuses are disclosed for incorporating a plurality of independently rotating rotors made from high-strength materials with a high-temperature superconductive (HTS) bearing technology into an open-core flywheel architecture to achieve a desired high energy density in the flywheel energy storage devices and to obtain superior results and performance.

The invention discloses a low voltage ride through control method of a permanent magnet direct drive wind power generation system. The control method simultaneously comprises control on a motor side converter, control on a power net side converter and control on a flywheel motor side converter. According to the invention, the power generation system can supply reactive power support to a power grid while a direct current chain voltage is stably controlled in the power grid failure process, so that the operation reliability and stability of the power generation system and the connected power grid during the power grid failure process are improved effectively.

The invention provides a lifting hydraulic system and a lifting machine with the hydraulic system. The lifting hydraulic system comprises an oil tank, lifting oil cylinders and a volume adjustable hydraulic pump / motor, wherein an oil inlet pipeline and an oil discharge pipeline of each lifting oil cylinder are connected to a node; and the volume adjustable hydraulic pump / motor comprises an oil passing cavity communicated between the node and the oil tank, a rotor arranged in the oil passing cavity, a transmission shaft with a first end connected with the rotor, and a flywheel connected to thesecond end of the transmission shaft. When the lifting oil cylinders discharge oil, the volume adjustable hydraulic pump / motor works as a hydraulic motor and drives the flywheel to store energy; and when the lifting oil cylinders are fed with the oil, the volume adjustable hydraulic pump / motor works as a hydraulic pump driven by the flywheel to feed the hydraulic oil into the lifting oil cylinders. The lifting hydraulic system provided by the invention can save a great amount of energy in frequent container stacking operation; the flywheel can be used as a counterweight so as to bring convenience to layout; moreover, the flywheel reduces the impact of the hydraulic oil onto each part of the system at the same time of saving the energy, and ensures the running stability of the lifting hydraulic system.

The invention provides a high-efficient flywheel energy storage device, comprising a shell, a motor arranged in the cavity of the shell, a flywheel and a support structure, wherein, the cavity is vacuumized; the motor is arranged under the flywheel; a flywheel shaft of the flywheel and a rotor of the motor are integrated into a whole; the support structure is formed by mixing a pivot thrust bearing and a permanent magnetic bearing. The device of the invention has the advantages of simple structure, convenient maintenance, low cost, good stability, simultaneous and quick charging and discharging and high energy storage efficiency.

The invention discloses a flywheel array energy storage system with multiple parallel-connected flywheel energy storage units. The flywheel array energy storage system comprises a public alternative current bus, a grid-tied static switch, a flywheel array controller, at least two flywheel energy storage units and unit controllers of the flywheel energy storage units, wherein the internal structures and the parameter characteristics of the flywheel energy storage units are completely identical; the flywheel energy storage units are tied into the public alternative current bus in a current source mode; and the number of the flywheel energy storage units can be increased or decreased randomly. According to the flywheel array energy storage system, a hierarchy control mode is adopted; a power necessary for maintaining the power balance of an alternative current grid is calculated by the flywheel array controller as an upper hierarchy controller, and the power is distributed to each flywheel energy storage unit controller by using a coordination control algorithm; and the unit controllers as a lower hierarchy controller utilize a flywheel energy storage unit control method to control a grid power conversion circuit, a flywheel motor power conversion circuit and a permanent magnetic synchronous motor to absorb or emit the power to the alternative current grid according to power instructions obtained by the unit controllers.

This invention relates to a flexible AC transmission system based on flywheel energy-storage including a double-feed flywheel energy-stored motor, an AC excitation supply, a monitor, a serial transformer and an inverse parallel two-way thyristor, in which, the supply includes a parallel side converter, a serial side converter and a capacitor, the AC end of the parallel side converter is connected with the rotor winding of the flywheel energy-stored motor, the two DC ends of which and those of the serial side converter are connected with two ends of the capacitor, the AC end of the serial converter is connected with the first winding of the serial transformer, the second winding of which is parallel to the inverse parallel two-way thyristor and one end of which is connected with the stator winding of the motor and the monitor device realizes by-pass protection by controlling the connection state of the thyristor.