Uninterruptible power generation system

Abstract

A power delivery system is disclosed including a primary power bus for transferring power to the facility from on-site generators, and a secondary power bus for transferring power to the facility from a utility. The system further includes a static disconnect switch capable of quickly isolating the facility from the utility power grid, and a controller for controlling the overall operation of the power delivery system. In a normal mode of operation, the utility supplies power approximately in the amount of the single largest load in the facility, with the remaining power being supplied by the on-site generators. If one or more of the generators go off-line, the power supply from the utility may be increased. Similarly, if the quality of the power supplied by the utility drops below a predetermined level, the static disconnect switch quickly opens and islands the facility, whereupon 100% of the power is supplied by the generators.

We claim:  
     
         1 . An uninterruptible power delivery system for supplying a power load of a facility within a high quality power range, said high quality power range being power within a predetermined voltage range, a predetermined frequency range and not being interrupted for more than a cycle, the uninterruptible power delivery system comprising: 
 a primary power supply from at least one generator located on-site to the facility; and    a secondary power supply from a utility.    
     
     
         2 . An uninterruptible power delivery system as recited in  claim 1 , wherein said at least one generator is capable of supplying 100% of the power load of the facility in the event said secondary power supply from said utility deviates outside of said high quality range.  
     
     
         3 . An uninterruptible power delivery system as recited in  claim 1 , wherein the facility islands in the event said secondary power supply from said utility deviates outside of said high quality range.  
     
     
         4 . An uninterruptible power delivery system as recited in  claim 3 , wherein said utility supplies power in a range large enough to prevent power flow to a grid supplied by the utility in the event of a drop in the power load of the facility, and small enough to allow said at least one generator to supply 100% of the facility load without tripping upon said islanding of said facility.  
     
     
         5 . An uninterruptible power delivery system as recited in  claim 1 , further including a switch capable of islanding the facility in less than a cycle in the event said secondary power supply from said utility deviates outside of said high quality range.  
     
     
         6 . An uninterruptible power delivery system as recited in  claim 1 , wherein said at least one generator supplies between 80% and 98% of the power load of the facility and said utility supplies between 20% and 2% of the power load of the facility during normal operation.  
     
     
         7 . An uninterruptible power delivery system as recited in  claim 6 , wherein said utility is capable of supplying more than 20% of the power load of the facility in the event that one or more of said at least one generator is off-line.  
     
     
         8 . An uninterruptible power delivery system as recited in  claim 6 , wherein said utility is capable of supplying 100% of the power load of the facility in the event that one or more of said at least one generator is off-line.  
     
     
         9 . An uninterruptible power delivery system as recited in  claim 1 , wherein the facility load is y kilowatts, and the single largest load in the facility is x kilowatts, said at least one generator supplying ((y−x)/y)×(100%) of the power load of the facility and said utility supplies (x/y)×(100%) of the power load of the facility during normal operation of the power delivery system.  
     
     
         10 . An uninterruptible power delivery system as recited in  claim 9 , wherein said at least one generator supplies y kilowatts in the event power from said utility drops outside of said high quality range.  
     
     
         11 . An uninterruptible power delivery system as recited in  claim 9 , wherein said utility supplies y kilowatts in the event power from said at least one generator drops outside of said high quality range.  
     
     
         12 . An uninterruptible power delivery system as recited in  claim 1 , further comprising a controller for controlling the operation of the power delivery system.  
     
     
         13 . An uninterruptible power delivery system as recited in  claim 1 , wherein said at least one generator generates waste heat in addition to power, said waste heat being supplied to the facility for use by the facility.  
     
     
         14 . An uninterruptible power delivery system as recited in  claim 1 , wherein the power delivery system does not include a short term stored power supply.  
     
     
         15 . An uninterruptible power delivery system for supplying a power load of a facility within a high quality range, said high quality range being power within a predetermined voltage range, a predetermined frequency range and not being interrupted for more than a cycle, the uninterruptible power delivery system comprising: 
 a primary power supply from at least one generator located on-site to the facility;    a secondary power supply from a utility; and    a static disconnect switch for isolating the facility from the power supply from said utility in less than a cycle in the event power to the facility from the utility is outside of said high quality range.    
     
     
         16 . An uninterruptible power delivery system as recited in  claim 15 , wherein said at least one generator is capable of supplying 100% of the power load of the facility in the event said secondary power supply from said utility deviates outside of said high quality range.  
     
     
         17 . An uninterruptible power delivery system as recited in  claim 15 , wherein the facility islands in the event said secondary power supply from said utility deviates outside of said high quality range.  
     
     
         18 . An uninterruptible power delivery system as recited in  claim 17 , wherein said utility supplies power in a range large enough to prevent power flow to a grid supplied by the utility in the event of a drop in the power load of the facility, and small enough to allow said at least one generator to supply 100% of the facility load without tripping upon said islanding of said facility.  
     
     
         19 . An uninterruptible power delivery system as recited in  claim 15 , wherein said at least one generator supplies between 80% and 98% of the power load of the facility and said utility supplies between 20% and 2% of the power load of the facility during normal operation.  
     
     
         20 . An uninterruptible power delivery system as recited in  claim 19 , wherein said utility is capable of supplying more than 20% of the power load of the facility in the event that one or more of said at least one generator is off-line.  
     
     
         21 . An uninterruptible power delivery system as recited in  claim 15 , wherein the facility load is y kilowatts, and the single largest load in the facility is x kilowatts, said at least one generator supplying ((y−x)/y)×(100%) of the power load of the facility and said utility supplies (x/y)×(100%) of the power load of the facility during normal operation of the power delivery system.  
     
     
         22 . An uninterruptible power delivery system as recited in  claim 21 , wherein said at least one generator supplies y kilowatts in the event power from said utility drops outside of said high quality range.  
     
     
         23 . An uninterruptible power delivery system as recited in  claim 21 , wherein said utility supplies y kilowatts in the event power from said at least one generator drops outside of said high quality range.  
     
     
         24 . An uninterruptible power delivery system as recited in  claim 15 , further comprising a controller for controlling the operation of the power delivery system.  
     
     
         25 . An uninterruptible power delivery system as recited in  claim 15 , wherein said at least one generator generates waste heat in addition to power, said waste heat being supplied to the facility for use by the facility.  
     
     
         26 . An uninterruptible power delivery system as recited in  claim 15 , wherein the power delivery system does not include a short term stored power supply.