Abstract:
Apparatus, system and method for providing supplementary power. A vessel is configured to receive and contain hydraulic fluid, where the vessel includes a piston configured within the vessel to be vertically displaced by the hydraulic fluid and provide pressure from the weight of the piston to a fluid supply line. A solenoid valve is operatively coupled to the fluid supply line; and connected to a flywheel power supply that includes a flywheel and a hydraulic drive adapter, wherein the hydraulic drive adapter is operatively coupled to the solenoid valve via the fluid supply line. A signal is received indicating a power outage, where the solenoid valve is further configured to open in response to the signal and provide the hydraulic fluid pressurized by the piston to the hydraulic drive adapter and causes the flywheel to operate and provide the supplementary power.

Description:
BACKGROUND 
       [0001]    Uninterruptible power supplies, also known as uninterruptible power sources (UPS) are electrical apparatuses known in the art that provide emergency power to a load when the input power source, typically mains power, fails. A UPS differs from an auxiliary or emergency power system or standby generator in that it will provide near-instantaneous protection from input power interruptions, by supplying energy stored in batteries, supercapacitors, or flywheels. The on-battery runtime of most uninterruptible power sources is relatively short (only a few minutes) but sufficient to start a standby power source or properly shut down the protected equipment. A UPS is typically used to protect hardware such as industrial equipment, computers, data centers, telecommunication equipment or other electrical equipment where an unexpected power disruption could cause injuries, fatalities, serious business disruption or data loss. UPS units range in size from units designed to protect a single computer without a video monitor (around 200 volt-ampere rating) to large units powering entire data centers or buildings. 
         [0002]    Rotary Flywheel UPS systems used in mission critical facilities provide very limited time to transition to back up generators after a power loss usually 15 to 45 seconds depending on the load. Theoretically, this “ride through” should be adequate to allow the backup generators to start. In the event that the backup generators fail to start, there is no time for an orderly shutdown of the systems. Costs associated with power failures are significant, and may collectively (billions of dollars annually). As an example, banks where millions of transactions are taking place every minute are exposed to significant losses during a power failure. Most mission critical facilities will install battery backup in order to provide adequate time for orderly shutdowns and to ensure that there is adequate time to get the backup generators started. Battery backup used to provide power to critical systems for an extended period of time is often expensive, requires dedicated space with special ventilation and fire protection systems, requires maintenance and is environmentally unfriendly among other things. 
       SUMMARY 
       [0003]    In one exemplary embodiment, an apparatus/system is disclosed for providing supplementary power, where the apparatus includes a vessel, configured to receive and contain fluid, a piston, configured within the vessel to be displaced by the fluid and provide pressure from the displacement, a fluid supply line, operatively coupled to an output of the vessel, a solenoid valve, operatively coupled to the fluid supply line; and a flywheel power supply, operatively coupled to the valve, wherein the flywheel power supply comprises a flywheel and a hydraulic drive adapter. The apparatus is configured to receive a signal indicating a power outage, the valve being further configured to open in response to the signal and provide fluid pressurized by the piston to the hydraulic drive adapter and cause the flywheel to operate and provide the supplementary power. The fluid may comprise at least one of an oil-based and water-based hydraulic fluid. 
         [0004]    In other exemplary embodiments, the apparatus/system may further comprise a fluid reservoir and a hydraulic pump, wherein the hydraulic pump is configured to pump fluid from the fluid reservoir to the vessel. The fluid reservoir may be operatively coupled to the hydraulic drive adapter and configured to receive fluid discharged from the hydraulic drive adapter. The apparatus may further comprise a check valve operatively coupled between the hydraulic pump and the vessel via the fluid supply line, wherein the check valve may be configured to directionally control flow of fluid to the vessel. The apparatus may still further comprise a pressure regulator valve, operatively coupled to the solenoid valve, wherein the pressure regulator valve is configured to regulate pressure provided by the piston in the fluid supply line. 
         [0005]    In other exemplary embodiments, a method is disclosed for providing supplementary power, wherein the method comprises the steps of receiving and containing hydraulic fluid in a vessel comprising a piston, positioned within the vessel, wherein the weight of the piston provides a pressure for the fluid in the vessel, and wherein the vessel is operatively coupled to a fluid supply line. The method may further comprise the steps of receiving a signal indicating a power outage, wherein receipt of the signal causes a solenoid valve to open and allow flow of fluid from the vessel to a hydraulic drive adapter of a flywheel power supply, and wherein the flow of fluid in the hydraulic drive adapter causes a flywheel of the flywheel power supply to operate and provide the supplementary power. 
         [0006]    In other exemplary embodiments, the method comprises the steps of receiving fluid in the vessel comprises pumping fluid from a fluid reservoir, via a hydraulic pump, to the vessel. Fluid discharged from the hydraulic drive adapter may be received in the fluid reservoir. Fluid to the vessel may be directionally controlled via a check valve operatively coupled between the hydraulic pump and the vessel. 
         [0007]    In still further embodiments, an apparatus/system is disclosed for providing supplementary power, comprising a vessel, configured to receive and contain hydraulic fluid, the vessel comprising a piston configured within the vessel to be vertically displaced by the hydraulic fluid and provide pressure from the weight of the piston to a fluid supply line. A solenoid valve may be operatively coupled to the fluid supply line. The apparatus may further include a flywheel power supply comprising a flywheel and a hydraulic drive adapter, wherein the hydraulic drive adapter is operatively coupled to the solenoid valve via the fluid supply line. The apparatus may be configured to receive a signal indicating a power outage, the solenoid valve being further configured to open in response to the signal and provide the hydraulic fluid pressurized by the piston to the hydraulic drive adapter and cause the flywheel to operate and provide the supplementary power. 
         [0008]    In other exemplary embodiments, the apparatus/system may comprise a fluid reservoir and a hydraulic pump, wherein the hydraulic pump is configured to pump hydraulic fluid from the fluid reservoir to the vessel. The fluid reservoir may be operatively coupled to the hydraulic drive adapter and configured to receive hydraulic fluid discharged from the hydraulic drive adapter. A check valve may also be operatively coupled between the hydraulic pump and the vessel via the fluid supply line, wherein the check valve is configured to directionally control flow of fluid to the vessel. A pressure regulator valve may be operatively coupled to the solenoid valve, wherein the pressure regulator valve is configured to regulate pressure provided by the piston in the fluid supply line. The vessel may further comprise a sensor configured to sense an amount of hydraulic fluid in the vessel and provide a signal to the hydraulic pump to modify operation based on the sensed amount. 
         [0009]    Further scope of applicability of the present disclosure will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0010]    The present invention is illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements and in which: 
           [0011]      FIG. 1  illustrates a hydraulic UPS system under one exemplary embodiment comprising a hydraulic fluid vessel/accumulator containing a sealed piston or weight for providing hydraulic fluid pressure that is released to a UPS flywheel when a solenoid valve is opened via a power failure signal; 
           [0012]      FIG. 2  illustrates a hydraulic UPS system under another exemplary embodiment comprising a hydraulic fluid vessel/accumulator containing a sealed piston or weight for providing hydraulic fluid pressure that is released to a plurality of UPS flywheels when one or more solenoid valves are opened via a power failure signal; and 
           [0013]      FIG. 3  illustrates a hydraulic UPS system under yet another exemplary embodiment comprising a plurality of hydraulic fluid vessel/accumulators each containing a sealed piston or weight for providing hydraulic fluid pressure that is released to a UPS flywheel when a solenoid valve is opened via a power failure signal. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    The figures and descriptions provided herein may have been simplified to illustrate aspects that are relevant for a clear understanding of the herein described devices, systems, and methods, while eliminating, for the purpose of clarity, other aspects that may be found in typical devices, systems, and methods. Those of ordinary skill may recognize that other elements and/or operations may be desirable and/or necessary to implement the devices, systems, and methods described herein. Because such elements and operations are well known in the art, and because they do not facilitate a better understanding of the present disclosure, a discussion of such elements and operations may not be provided herein. However, the present disclosure is deemed to inherently include all such elements, variations, and modifications to the described aspects that would be known to those of ordinary skill in the art. 
         [0015]    Turning to  FIG. 1 , an exemplary embodiment is provided of a UPS power system  100  comprising a piston  101  that is contained and preferably sealed within vessel/accumulator  102  (hereafter “vessel”). In one embodiment, piston  101  is manufactured from a dense and/or heavy material such as a metal or alloy (e.g., steel, tungsten, brass, etc) or plastic, rubber, or any suitable combinations thereof. Piston  101  may be coated or encased in a protective material to prevent corrosion and the like. Vessel  102  is filled with a fluid such as hydraulic fluid which may be oil or water-based fluid which may be provided from fluid reservoir  109 , via hydraulic pump  110 . Hydraulic pump may be a hydrostatic or hydrodynamic pump, depending on the application. When configured, hydraulic pump  110  provides positive displacement for piston  101  in which the displacement (flow through the pump per rotation of the pump) is fixed, or may be configured as a variable displacement pump, which allows the displacement to be adjusted. Flow from hydraulic pump  110  may be controlled via check valve  111 . 
         [0016]    As vessel  102  is filled with hydraulic fluid, the weight of piston  101  provides a counter-pressure within vessel  102 . When vessel  102  is completely filled, the piston  101 /vessel  102  may be considered at a maximum pressure. A hydraulic fluid supply line  103  is preferably coupled to a solenoid valve  104  which should be configured to be naturally in a “closed” state. In one embodiment, solenoid valve  104  is operatively coupled to a power system configured to provide a signal (PWR) indicating that power has failed, and that back-up power from system  100  is required. In one embodiment, solenoid valve  104  may be held in a closed position via a continuous PWR signal, indicating that power in a primary system is operating normally. Once power in the main system turns off, the PWR signal is no longer being received, causing solenoid valve  104  to open. As a result, the pressure from piston  101  causes fluid in vessel  102  to flow through valve  104  and pressure regulator valve  105  and into flywheel rotary UPS  106 . 
         [0017]    In one embodiment, UPS  106  operates under flywheel energy storage principles by accelerating a rotor, such as flywheel  108  via hydraulic drive adapter  107  to a very high speed and maintaining the energy in the system as rotational energy. When energy is extracted from the system, the flywheel&#39;s rotational speed may be reduced as a consequence of the principle of conservation of energy; adding energy to the system correspondingly results in an increase in the speed of the flywheel. 
         [0018]    In a simplified embodiment, UPS  106  may comprise a rotor suspended by bearings inside a vacuum chamber to reduce friction, connected to a combination electric motor and electric generator. The flywheel may be a large steel flywheel rotating on mechanical bearings. In one embodiment, the flywheel may comprise carbon-fiber composite rotors that have a higher tensile strength than steel and are an order of magnitude less heavy. Magnetic bearings may be used used instead of mechanical bearings, to reduce friction. In one embodiment, high-temperature superconductor (HTSC) bearings or hybrid bearings may be used, where permanent magnets support a load and high-temperature superconductors are used to stabilize it. Superconductors may be advantageous in stabilizing a load because they may operate as diamagnets. If the rotor tries to drift off center, a restoring force due to flux pinning (magnetic stiffness of the bearing) restores it. Since flux pinning is a factor for providing the stabilizing and lifting force, the HTSC can be made much more easily for flywheel energy storage than for other uses. HTSC powders can be formed into arbitrary shapes so long as flux pinning is strong. 
         [0019]    Compared with other techniques for storing electricity, flywheel energy storage systems have long lifetimes (lasting decades with little or no maintenance. Full-cycle lifetimes for flywheels may range from in excess of 10 5 , up to 10 7 , cycles of use), and provide high energy density (100-130 W·h/kg, or 360-500 kJ/kg), and large maximum power output. The energy efficiency (ratio of energy out per energy in) of flywheels can be as high as 90%. Typical capacities may range from 3 kWh to 133 kWh. 
         [0020]    The energy density of flywheel  108  may vary, depending on the rotor geometry used and the properties of material being used. For single-material, isotropic rotors, this relationship may be expressed as 
         [0000]    
       
         
           
             
               
                 E 
                 m 
               
               = 
               
                 K 
                  
                 
                   ( 
                   
                     σ 
                     ρ 
                   
                   ) 
                 
               
             
             , 
           
         
       
     
         [0000]    where E is the kinetic energy of the rotor (J), m is the rotor&#39;s mass (kg), K is the rotor&#39;s geometric shape factor, σ is the tensile strength of the rotor material (Pa) and ρ is the material&#39;s density (kg/m 3 ). 
         [0021]    Continuing with the example of  FIG. 1 , hydraulic fluid entering UPS  106  at a predetermined pressure specified by regulator valve  105  causes hydraulic drive adapter  107  to operate flywheel  108  for generating power (OUT) back to the main power system. In one embodiment, hydraulic fluid exiting UPS  106  is fed back to fluid reservoir  109 , which regenerates the fluid for future use in vessel  102  via hydraulic pump  110 . Thus, under normal operating conditions in one embodiment, flywheel  108  of the UPS is set to rotate at a high speed. Upon power failure, flywheel  108  continues to rotate to provide electrical power. When solenoid valve  104  opens, pressurized fluid flows, and continues to flow under pressure provided by piston  101 . Hydraulic drive adapter  107  rotates as a result of the pressurized fluid and the flywheel continues to rotate until the fluid is completely discharged and piston  101  reaches the bottom of the vessel. 
         [0022]    The embodiment of  FIG. 1  (as well as other embodiments disclosed herein) provides a simple and elegant solution for providing uninterruptable power to a system using hydraulic technology. As pressure for the hydraulic fluid is being provided by the weight of piston  101  in one embodiment, the fluid may be easily regulated and input into UPS  106  for the creation of energy. Thus no expensive and/or complicated genset arrangements of secondary power origination are required. Of course, the piston arrangement in the present disclosure may be combined with such systems as required. Furthermore, pressure from piston  101  may be complimented and/or substituted by air pressure if necessary. In this embodiment, a bladder may be provided within vessel  102  and pressurized to achieve the required fluid pressure. Used alone, the inflated bladder would provide the pressure within vessel  102  to discharge the hydraulic fluid. Used in combination with piston  101 , the bladder would provide additional pressure that that already being provided by the weight of piston  101 . Such an embodiment may be advantageous when variable pressure may be required; the bladder would provide an efficient means for adding necessary pressure to the existing piston in the arrangement. 
         [0023]    Turning to  FIG. 2 , another exemplary embodiment is provided, which is similar to the embodiment of  FIG. 1 , except that the piton  101  and vessel  102  configuration is used to provide fluid to a plurality of UPS systems (106, 114), where each of the UPS systems may provide separate backup power (OUT) to separate system, or alternately combined (shown by connecting dotted line between OUT signals in  FIG. 2 ). Such a configuration may be advantageous in applications where (a) multiple, smaller UPS systems may be used in lieu of a more expensive, singular UPS, and/or (b) providing targeted UPS capabilities to multiple locations within a large installation. 
         [0024]    The exemplary system  200  of  FIG. 2  comprises a piston  101  that is contained and preferably sealed within vessel/accumulator  102  (hereafter “vessel”). Similar to the embodiment of  FIG. 1 , piston  101  may be manufactured from a dense and/or heavy material such as a metal or alloy (e.g., steel, tungsten, brass, etc.) or plastic, rubber, or any suitable combinations thereof. Piston  101  may be coated or encased in a protective material to prevent corrosion and the like. Vessel  102  is filled with a fluid such as hydraulic fluid which may be oil or water-based fluid which may be provided from fluid reservoir  109 , via hydraulic pump  110 . Hydraulic pump may be a hydrostatic or hydrodynamic pump, depending on the application. When configured, hydraulic pump  110  provides positive displacement for piston  101  in which the displacement is fixed, or may be configured as a variable displacement pump, which allows the displacement to be adjusted. Flow from hydraulic pump  110  may be controlled via check valve  111 . 
         [0025]    As vessel  102  is filled with hydraulic fluid, the weight of piston  101  provides a counter-pressure within vessel  102 . When vessel  102  is completely filled, the piston  101 /vessel  102  may be considered at a maximum pressure. A hydraulic fluid supply line  103  is preferably coupled to solenoid valves  104 ,  112  which may be configured to be naturally in a “closed” state. In one embodiment, solenoid valves  104 ,  112  are respectively coupled to a power system configured to provide a signal (PWR) indicating that power has failed, and that back-up power from system  200  is required. In one embodiment, solenoid valves  104 ,  112  may be held in a closed position via a continuous PWR signal, indicating that power in a primary system is operating normally. Once power in the main system turns off, the PWR signal is no longer being received, causing solenoid valves  104 ,  112  to open. As a result, the pressure from piston  101  causes fluid in vessel  102  to flow simultaneously through valves  104 ,  112  and pressure regulator valves  105 ,  113  and respectively into flywheel rotary UPS  106 ,  112 . 
         [0026]    Similar to the embodiment of  FIG. 1 , UPS  106  and  114  may operate under flywheel energy storage principles by accelerating a rotor, such as respective flywheels  108 ,  116  via hydraulic drive adapters  107 ,  115  to a very high speed and maintaining the energy in the system as rotational energy. When energy is extracted from the system (OUT), the flywheel&#39;s rotational speed may be reduced as a consequence of the principle of conservation of energy; adding energy to the system correspondingly results in an increase in the speed of the flywheel. 
         [0027]    In the embodiment of  FIG. 2 , solenoid valves  104 ,  112  are controlled via the same PWR signal. It should be appreciated by those skilled in the art that separate, independent PWR signals may be provided to solenoid valves  104 ,  112 , which in turn would provide separate backup power (OUT) for each UPS  106 ,  114 . In this example, care should be taken to configure system  200  so that, for example, a prolonged use of one UPS (e.g.,  114 ) does not drain hydraulic fluid to a point where the activation of another UPS (e.g.,  106 ) does not create a scenario where insufficient fluid remains in vessel  102  to power a newly-activated UPS. In one embodiment, hydraulic pump may comprise one or more sensors ( 150 ) indicating the amount of fluid being pumped, and may further be in communication with one or more sensors ( 151 ) in vessel  102  which may monitor the amount of remaining fluid. In the event that an insufficient fluid supply condition is sensed, hydraulic pump  110  may be configured to increase pumping capacity from reservoir  109  to provide sufficient fluid to vessel  102 . 
         [0028]    Turning to  FIG. 3 , another exemplary embodiment is provided, where multiple vessels ( 102 ,  121 ) and respective pistons ( 101 ,  120 ) are used to drive a UPS  106 . Such a configuration may be advantageous for provided extended hydraulic backup capabilities to UPS  106 . As similarly described above in connection with  FIGS. 1-2 , UPS power system  300  comprises pistons  101 ,  120  that are contained and preferably sealed within respective vessel/accumulators  102 ,  120 . In one embodiment, pistons  101 ,  120  are manufactured from a dense and/or heavy material such as a metal or alloy (e.g., steel, tungsten, brass, etc) or plastic, rubber, or any suitable combinations thereof. Pistons  101 ,  120  may be coated or encased in a protective material to prevent corrosion and the like. Vessels  102 ,  121  are filled with a fluid such as hydraulic fluid which may be oil or water-based fluid which may be provided from fluid reservoir  109 , via hydraulic pump  110 . Hydraulic pump  110  may be a hydrostatic or hydrodynamic pump, depending on the application. When configured, hydraulic pump  110  provides positive displacement for pistons  101 ,  120  in which the displacement is fixed, or may be configured as a variable displacement pump, which allows the displacement to be adjusted. Flow from hydraulic pump  110  may be controlled via check valve  111 . 
         [0029]    As vessels  102 ,  121  are filled with hydraulic fluid, the weight of pistons  101 ,  120  provide a counter-pressure within vessels  102 ,  121 . When vessels  102 ,  121  are completely filled, the respective piston weight may provide a maximum pressure. A hydraulic fluid supply line  103  is preferably coupled to both vessels  102 ,  121  and a solenoid valve  104  which should be configured to be naturally in a “closed” state. In one embodiment, solenoid valve  104  is operatively coupled to a power system configured to provide a signal (PWR) indicating that power has failed, and that back-up power from system  100  is required. In one embodiment, solenoid valve  104  may be held in a closed position via a continuous PWR signal, indicating that power in a primary system is operating normally. Once power in the main system turns off, the PWR signal is no longer being received, causing solenoid valve  104  to open. As a result, the pressure from pistons  101 ,  120  cause fluid in vessels  102 ,  121  to flow through valve  104  and pressure regulator valve  105  and into flywheel rotary UPS  106 . 
         [0030]    In one embodiment, vessels  102 ,  121  may operate to provide hydraulic fluid simultaneously. In another embodiment, vessels may be designated as “primary” (e.g.,  102 ) and “secondary” (e.g.,  121 ) vessels, and wherein the secondary vessel is equipped with its own solenoid (not shown). Each vessel may be equipped with sensors, similar to the embodiment of  FIG. 2 , where the level of fluid is sensed and monitored. Here, only the primary vessel ( 102 ) discharges hydraulic fluid upon activation of solenoid valve  104 . As hydraulic fluid is drained, there may come a point where hydraulic pump  110  is not providing sufficient fluid back to vessel  102  to maintain UPS capabilities. If the sensed level of hydraulic fluid drops below a predetermined threshold, the sensor for the primary vessel activates a solenoid valve for the secondary vessel to provide a hydraulic fluid “assist” along a common fluid supply line  103 . With the addition of fluid being provided by the secondary vessel  121 , the primary vessel  102  does not have to expend as much fluid, which in turn may allow hydraulic pump  110  to “catch up” with any deficient fluids. If the fluid levels in the primary vessel  102  are raised back to an acceptable threshold, the sensor for the primary vessel  102  may close the solenoid for the secondary vessel. It should be understood by those skilled in the art that further vessels may be added, depending on the application, to create a daisy-chained configuration of vessels for extended UPS operation. Of course, the multiple vessel configuration of  FIG. 3  may be combined with the multiple UPS configuration of  FIG. 2  to provide still further operational UPS capabilities. 
         [0031]    Continuing with the embodiment of  FIG. 3 , UPS  106  operates under flywheel energy storage principles by accelerating a rotor, such as flywheel  108  via hydraulic drive adapter  107  to a very high speed and maintaining the energy in the system as rotational energy. When energy is extracted from the system, the flywheel&#39;s rotational speed may be reduced as a consequence of the principle of conservation of energy; adding energy to the system correspondingly results in an increase in the speed of the flywheel. 
         [0032]    In a simplified embodiment, UPS  106  may comprise a rotor suspended by bearings inside a vacuum chamber to reduce friction, connected to a combination electric motor and electric generator. The flywheel may be a large steel flywheel rotating on mechanical bearings. In one embodiment, the flywheel may comprise carbon-fiber composite rotors that have a higher tensile strength than steel and are an order of magnitude less heavy. Magnetic bearings may be used instead of mechanical bearings, to reduce friction. In one embodiment, high-temperature superconductor (HTSC) bearings or hybrid bearings may be used, where permanent magnets support a load and high-temperature superconductors are used to stabilize it. 
         [0033]    Hydraulic fluid entering UPS  106  at a predetermined pressure specified by regulator valve  105  causes hydraulic drive adapter  107  to operate flywheel  108  for generating power (OUT) back to the main power system. In one embodiment, hydraulic fluid exiting UPS  106  is fed back to fluid reservoir  109 , which regenerates the fluid for future use in vessel  102  via hydraulic pump  110 . 
         [0034]    In the above configurations, the flywheel UPS may be configured to continuously rotate by getting power from the grid. Accordingly, the output power is advantageously protected from power distortions from the grid. In an alternate embodiment, power may be provided to the flywheel UPS and to the pump. In such a configuration, the power to the UPS is continuous, and the power to the pump is only needed after power is restored, where the pump is utilized to refill and re-pressurize the vessel. As the pump is continuously running, this would cause the flywheel to rotate, which in turn may vitiate the need for a power supply to the flywheel UPS. Such a configuration would be advantageous in reducing installation costs. 
         [0035]    In the foregoing Detailed Description, it can be seen that various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment.