CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of United States Provisional Application No. 63/391,391, filed July 22, 2022, the disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

[0002] This invention relates, in general, to energy storage and management systems. In particular, this invention relates to a multi-input hybrid grid system.

[0003] Advanced energy production systems (AES), such as wind, solar, tidal, and other sources of power are becoming more available. They all have complex controls that regulate their output, or must disconnect their output when the available power no longer matches the needs of the energy distribution system. The regulating circuits required for power amplitude and frequency control can consume large amounts of energy.

[0004] Hydraulic management and storage systems use accumulators to store hydraulic fluid under pressure and release the stored pressure energy as a mechanical output to drive a device. These systems typically capture energy that would be wasted in the form of heat, such as vehicle braking energy, and re-release the energy when a demand is signaled. The accumulator storage systems are sized to capture a predetermined amount of energy and provide a controlled release of the stored energy through valves regulating fluid flow into a hydraulic motor. It would be desirable however, to provide an improved multi-input grid system that can easily transition from storing excess energy to using stored energy to augment waning power from an AES. SUMMARY OF THE INVENTION

[0005] This invention relates, in general, to energy storage and management systems. In particular, this invention relates to a multi-input hybrid grid system. In one embodiment, a multi-input hybrid grid system includes an accumulator bank within a first container, the first container defining a hydraulic fluid reservoir therein, an advanced energy production system (AES), a multi-function pump/motor (MPM) configured to seamlessly transition from storing excess energy to using stored energy to augment waning power from the AES, a drive motor, and a generator. A first pump/motor is connected between the accumulator bank and the hydraulic fluid reservoir. A second pump/motor is connected the MPM and the hydraulic fluid reservoir, and operatively connected to the fixed displacement pump/motor, and an engine is operatively connected to the AES. The MPM, the generator, the drive motor, and the engine are operatively connected.

[0006] In a second embodiment, a multi-input hybrid grid system includes an accumulator bank within a first container, the first container defining a hydraulic fluid reservoir therein, an advanced energy production system (AES), a multi-function pump/motor (MPM) configured to seamlessly transition from storing excess energy to using stored energy to augment waning power from the AES, an engine operatively connected to the AES, and a generator/motor. A first pump/motor is connected between the accumulator bank and the hydraulic fluid reservoir. A second pump/motor is connected the MPM and the hydraulic fluid reservoir, and operatively connected to the fixed displacement pump/motor. The MPM, the generator/motor, and the engine are operatively connected.

[0007] In a third embodiment, a multi-input hybrid grid system includes an accumulator bank within a first container, the first container defining a hydraulic fluid reservoir therein, an advanced energy production system (AES), one of a chain drive and a belt drive, a multi-function pump/motor (MPM) connected between the accumulator bank and a hydraulic fluid reservoir within the accumulator bank, the MPM configured to seamlessly transition from storing excess energy to using stored energy to augment waning power from the AES, an engine operatively connected to the AES, a drive motor, and a generator. The one of a chain drive and a belt drive operatively connects the MPM and the generator, and the engine, the drive motor, and the one of a chain drive and a belt drive are operatively connected.

[0008] Various aspects of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Fig. 1 is a schematic illustration of a first embodiment of a multi-input hybrid grid system according to this invention.

[0010] Fig. 2 is an illustration of one embodiment of the multi-input hybrid grid system according to this invention.

[0011] Fig. 3 is an elevational view of a container housing a generator, a drive motor, an engine, and an MPM.

[0012] Fig. 4 is a perspective view of a bank of accumulators.

[0013] Fig. 5 is a schematic illustration of a second embodiment of a multi-input hybrid grid system according to this invention.

[0014] Fig. 6 is a schematic illustration of a third embodiment of a multi-input hybrid grid system according to this invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0015] One embodiment of a multi-input hybrid grid system is shown at 10 in Figs. 1 and 2. The embodiment of the multi-input hybrid grid system 10 will allow legacy regulators, such as are known in wind farms and solar fields, to work when the power into the system 10 can be efficiently matched to the power out of the system 10. The multi-input hybrid grid system 10 includes one or more sources of energy, such as one or more advanced energy production systems (AES) 12, one of which is shown in Fig. 2, linked though clutches 14 or one-way ratchets to an engine, such as the engine 16 shown in Fig. 1.

[0016] Primary regulation of the system 10, however, is handled by a multi-function pump/motor (MPM) 18, housed within a container 20, shown in Figs. 2 and 3. The MPM 18 seamlessly transitions from storing excess energy to using stored energy to augment waning power from the AES 12, including but not limited to, wind (such as one or more of the wind turbines 22 shown in Fig. 2), solar, natural gas, nuclear energy, coal burning power plants, and tidal energy systems, as shown schematically at 23. Fluid pressure rails or conduits 24 connect an accumulator bank 26, the MPM 18, and the AES 12.

[0017] As shown in Fig. 2, the AES 12, comprising, for example, one or more of the wind turbines 22, is connected to the container 20, within which is housed a generator 28, a drive motor 30, the engine 16, and the MPM 18. The MPM 18 within the container 20 is also connected to a hydraulic fluid reservoir 32 that is defined within the accumulator bank 26, and to the accumulator bank 26. Each accumulator bank 26 has a plurality of accumulators 34. The MPM 18 is also connected to a user of electricity 36, such as a power grid, a factory, or other building. The accumulators 34 may be any type of pressurized fluid storage device, including but not limited to a piston accumulator, a bladder, a metal bellows, a diaphragm accumulator, or a mechanical spring accumulator. [0018] In the illustrated embodiment, the engine 16 is an internal combustion engine (ICE) and is used to bum any desired type of fuel. Tn the illustrated embodiment, a single drive motor 30 is used. It will be understood however, that power may come from one or more drive motors 30. Conversely, in a known, non-hybrid system, when the energy coming from the AES 12 is adequate to supply all needed power to a generator, the grid is powered, and excess energy is disposed of, in the form of heat. Alternatively, a percentage of energy generating capability may be turned off. As energy wanes, the ICE 16 may be started to augment, and eventually replace, AES 12 power until the AES 12 power becomes available again. As the AES 12 comes on-line again, the ICE 16 may lower output levels until turning off. Output from the generator 28 remains stable even in a situation wherein energy in the illustrated system 10 is not fully captured.

[0019] A chain or belt drive 38 connects the MPM 18 and the generator 28.

Alternatively, the belt drive 38 may be any connecting mechanism for a bi-directional power take off (PTO). This allows a motor from the AES 12 to add as much energy as it is capable of at all times. The MPM 18, the belt drive 38, the generator 28, the drive motor 30, and the ICE 16 are connected by spinning shafts 40 and clutches 14, as shown in Fig. 1. Although the illustrated grid system 10 is described as including the generator 28, it will be understood that a compressor may be used in lieu of the generator 28. [0020] The speed or RPM of any or all of the MPM 18, the ICE 16, the generator 28, and the drive motor 30, may be regulated by the MPM 18 in a pump mode that stores the energy in the accumulators 34 that are sized to create a total system 10 that eliminates or nearly eliminates the need for the ICE 16. As the maximum power from the AES 12 drops below the power needed for the generator 28, the MPM 18 switches to a motor mode, such as with the ICE 16 described above. The MPM 18 may sustain all the output to the generator 28 until such time that a charge in the accumulators 34 is depleted. Only as the accumulators 34 reach a zero charge would the ICE 16 need to be started to maintain power to the grid 36. Regardless of how often the ICE 16 is used, it will only be used when all the aggregate power from the AES 12 has been used. None of its energy production is wasted.

[0021 ] Referring now to Fig. 5, a second embodiment of the multi-input hybrid grid system is shown at 41. The multi-input hybrid grid system 41 is similar to the multi-input hybrid grid system 10 and includes the MPM 18 connected to the hydraulic fluid reservoir 32, and a plurality of the accumulator banks 26 A, 26B, and 26C within a container 42 that defines a self-contained energy storage system. As described above in reference to Fig. 1, the MPM 18 may be housed in a container, such as the container 20. The container 20 may also be configured to house the generator 28, the drive motor 30, and the ICE 16. The MPM 18, the generator 28, the drive motor 30, and the ICE 16 are connected by the spinning shafts 40 and the clutches 14.

[0022] Each of the accumulator banks 26 A, 26B, and 26C is configured to operate independently or with an additional one or more of the accumulator banks 26A, 26B, and 26C. Each accumulator bank 26 A, 26B, and 26C includes a fixed displacement pump/motor 44 connected between the accumulator banks 26 A, 26B, and 26C and a hydraulic fluid reservoir 48. It will be understood that the pump/motor 44 may be a variable displacement pump/motor when required.

[0023] The plurality of accumulators 34 in the accumulator banks 26 A, 26B, and 26C are configured to provide a specified, desired amount of energy. However, the multiinput hybrid grid system 41 may be provided with only one of the accumulator banks 26 A, 26B, and 26C. For example, in an embodiment of the multi-input hybrid grid system 41 having only one of the accumulator banks 26A, 26B, and 26C, it may be advantageous for the pump/motor 44 to be a variable displacement pump/motor, such as when less complicated external systems are being controlled. The container 42 of the multi-input hybrid grid system 41 may be configured to be used as a reservoir for hydraulic fluid such as the reservoirs 32 and 48, and may include a filtration system (not shown) that is structured and configured to be serviced and maintained by a system user. The self-contained energy storage system within the container 42 may also include a crumple system (not shown) used to allow for safe discharge of one or more structurally failed accumulators 34.

[0024] The self-contained energy storage system within the container 42 may also include a controller, such as a computer (not shown) provided with an algorithm that can monitor and report energy storage system status and that can be set to different modes from a central location or from a remote location.

[0025] In the illustrated embodiment, the MPM 18 is connected to the hydraulic fluid reservoir 32 and to each of a normally variable displacement pump/motor 46 that is associated with each of the accumulator banks 26 A, 26B, and 26C of the multi-input hybrid grid system 41. The variable displacement pump/motor 46 is set to maintain an industry standard rail pressure. When multiple accumulator banks 26A, 26B, and 26C are employed, such as illustrated in Figs. 5 and 6, the variable displacement pump/motors 46 in each of the accumulator banks 26 A, 26B, and 26C are fluidly connected to each other and to the MPM 18. The fixed displacement pump/motor 44 and the variable displacement pump/motor 46 are connected by spinning shafts 40.

[0026] The container 42 may include mounting structures configured to interface with one or more of the pump/motors 44 and 46, motors 30, generators 28, engine 16, and any other device that may be operated by the spinning shaft, schematically illustrated at 40. [0027] Fluid conduits 24 connect the accumulator banks 26 A, 26B, and 26C, pump/motors 44, pump/motors 46, the MPM 18, and the hydraulic fluid reservoirs 32 and 48. One or more valve systems (not shown) may be mounted in the fluid conduits 52 and may be configured as a charge/discharge and safety system.

[0028] In a simplest embodiment of the system 41, the MPM 18 monitors the RPM and/or the output of the load from the AES 12. If the load is trying to spin faster than desired, the main MPM 18 pumps fluid into the system 41. The variable displacement pump/motors 46 required to regulate the rail pressure will spin in a first direction acting as motors, causing the fixed displacement pump/motors 44 to operate as pumps and charge the accumulator banks 26 A, 26B, and 26C.

[0029] Whenever it is determined that the load is operating at too low of an output, the MPM 18 changes to a motoring mode, providing as much as 100% of the energy needed to keep the load operating properly. When this energy is needed by the system 41 , the displacement of the pump/motors 46 drops to a point wherein they begin to spin in a second direction to maintain rail pressure in the system 41. Thus, the MPM 18 is bidirectional or multi-mode wherein the MPM 18 may spin in two directions to regulate the pressure rail based entirely on the rail pressure and without any controls beyond on and off. [0030] The design of the system is advantageous because systems that inherently work without the need for outside controls tend to be inherently stable systems. The stability simplifies the measures needed to make the system 41 reliable. The illustrated system 41 could work with nothing more than a flywheel governor, the spinning shaft, and some mechanical pressure relief valves to keep the accumulators 34 from over charging. When all the accumulators 34 are depleted, the system 41 will stop until energy is available to recharge it. This mechanical system 41 is so robust is that even if the controller is hacked or otherwise compromised, the base mechanical function cannot be changed. The system 41 will still charge, discharge, and protect itself from damage by the robust mechanical system.

[0031] Controls may be added to allow remote monitoring of the system 41 and to optimize the systems function. For example, unlike chemical batteries, accumulators last longer with deep charging and discharging cycles. So, at times or in situations when only small amounts of energy are needed or available, as little as one accumulator bank 26A, 26B, and 26C at a time will be charging or discharging. The rest of the system will simply be in a standby mode or condition. Such controls help the system 41 last longer and often provide notice or an indication that something is not operating properly, thus allowing repairs to be made before function is lost.

[0032] Referring now to Fig. 6, a third embodiment of the multi-input hybrid grid system is shown at 60. The multi-input hybrid grid system 60 is substantially similar to the multi-input hybrid grid system 41, but includes an electric generator/motor 62 instead of the generator 28 and the drive motor 30.

[0033] In the illustrated embodiment of the multi-input hybrid grid system 60, the generator/motor 62 may be started with the MPM 18. Alternatively, the generator/motor 62 may be already spinning as a generator when the needs of the grid 36 change, thus field current need only be maintained to the generator/motor 62 so that it continues to efficiently run as a motor. [0034] For example, if the pressure within the fluid pressure rail 24 increases to a value above a set rail pressure, then any accumulator bank 26 A, 26B, and 26C that is on will start charging. Should rail pressure drop below the set rail pressure, the accumulator bank 26 A, 26B, and 26C will start discharging.

[0035] It will be understood that, if desired, the systems 10, 41, and 60 may include multiple pump/motors 46 with separate, independent rail pressures when hydraulic systems to which the system 10, 41, and 60 are attached need to be isolated from each other. Additionally, the systems 10, 41, and 60 may include accumulator banks 26A, 26B, and 26C with separate pump/motors 46 configured to run completely isolated systems that can use the same accumulators 34 for energy storage.

[0036] Advantageously, the embodiments of the multi-input hybrid grid systems 10, 41, and 60 described herein are scalable and serviceable, i.e., adaptable to any energy need in any environment, and structured and configured to be serviced and maintained by a system user. For example, the various components and sub-components of the multiinput hybrid grid systems 10, 41, and 60 may be scaled as needed, including but not limited to the accumulator banks 26, 26 A, 26B, and 26C, the accumulator banks 26 A, 26B, and 26C with the associated fixed displacement pump/motor 44 and the variable displacement pump/motor 46, and any of the generator 28, the drive motor 30, the engine 16, and the MPM 18 or any combination thereof. Additionally, the multi-input hybrid grid systems 10, 41, and 60 may provide power to multiple isolated grids 36. Similar to an electrical system, the accumulator banks 26 A, 26B, and 26C and the associated pump/motors 44 and 46 may be arranged in parallel or in series. Further, the multi-input hybrid grid systems 10, 41, and 60 are configured to operate like a mechanical version of a battery.

[0037] The principle and mode of operation of this invention have been explained and illustrated in its preferred embodiment. However, it must be understood that this invention may be practiced otherwise than as specifically explained and illustrated without departing from its spirit or scope.