Abstract:
A transformer having variable reluctance, that controls the amount of power conveyed from an input to a load, based on a value selected by a computer control. The load power is varied by controlling the section and air gap between two parallel iron cores and a magnetic reluctance shifter positioned between the cores to vary the magnetic reluctance. The shifter is rotated by a motor. The position of the shifter varies the reluctance of the transformer and thus varies the amount of voltage transmitted from the primary winding to the secondary winding of the transformer. The iron core transformer is mounted in a non-magnetic frame and the windings are made from insulated braided copper strips, or insulated twisted cable.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This is a continuation-in-part of U.S. patent application Ser. No. 10/653,618, filed on Sep. 3, 2003 now abandoned. 

   BACKGROUND OF THE INVENTION 
   The invention relates to a modular transformer that can be used in a power substation for power transmission in the high and medium voltage ranges and in a distribution power panel for low voltage. The transformer utilizes two parallel iron cores with a rotational shifter located between the cores. The position of the shifter determines the amount of voltage reduction between the primary and secondary windings of the transformer. 
   Several transformers according to the invention can be located in different points of a network transmission line to control the uniform power distribution to the customers. The transformer can be made in different dimensions for a wide range of powers, for a single phase and two phase as well as a three phase system, without limitation of size and dimension, because all components can made by customer design or bought in the market. 
   SUMMARY OF THE INVENTION 
   It is an object of the invention to use energy produced by any electric generator (or by public utilities) and to dispense it in the desired optimal quality to the ultimate user plant. 
   The present invention relates to an electric transformer with a power control output that can be used to operate and control a power reducer. The transformer according to the invention comprises two parallel laminated iron cores with a primary and secondary winding made whit insulated and flexible braided copper strips or twisted cables. The cores are supported in a non-magnetic frame and have a spacer in-between them, to create an air gap between the cores. There is a rotational magnetic shifter mounted between the cores. The shifter is made of iron lamination. The shifter is connected to a shaft and a motor. 
   Rotation of the shaft by the motor causes the shifter to rotate and vary the position of the shifter and the air gap between the cores. This varies the power reduction between the primary and secondary windings by varying the magnetic reluctance of the transformer. The rotation of the shifter can be programmed according to pre-set parameters. 
   The transformer according to the invention can be installed through connection bars to the automatic main breakers, in different positions of electric power line, for example:
     1—in the middle of high voltage input to the high voltage output.   2—in the middle of high voltage input to the medium voltage output.   3—in the middle of medium voltage input to the low voltage output.   

   The voltage control power can be used in high and medium voltage, for example: 
   1)—primary winding from 170,000 to 15,000 volt and secondary winding from 17,000 to 2000 volt, as required by customers, in a single phase or three phases. 
   2)—primary winding from 17,000 to 2,000 volt and secondary winding to 100 volt or 120, 240; 277; 365; 600, 900 volt; as required by customer, in a single phase or three phases. 
   The voltage reduction and control stabilization can be achieved in the secondary winding from 1 to 60%, or increase from 1 to 25%. The amperage in the secondary winding in the substation transformer can vary from 50 to 5000 amperes. 
   The transformer according to the invention simultaneously operates in conjunction with any commercial system for voltage control, current control performance, and power factor correction and can provide not only energy saving and cost reduction and prevent blackouts, but also reduce the power consumption during peak demand periods. 
   Conventional control power and reducer systems in power plants have been available for many years: by manually reducing voltage to the transmission line by stepping down the input power from 5 to 10%. 
   In a conventional power reducer system, using a parallel capacitor with variable range of capacitive power, it is possible to automatically control the power factor correction. The system according to the invention can have similar automatic control of power factor correction during the operational time of control and reduction. 
   When filter networks, surge suppressors and isolation transformers are combined with a voltage regulator such as the transformer according to the invention, the results provide an ideal solution to the power quality transmission line, regardless of whether the connected load is capacitive, resistive or inductive. 
   The transformer according to the invention will maintain a constant output voltage within +/−1% or better, regardless of input voltage variations from +10% to 20% of the nominal input value. The transformer according to the invention is also designed and rated to meet standard industry Kva ratings for maximum application compatibility with existing installations. 
   The performance of the transformer according to the invention is guaranteed under all power factor conditions. 
   The principal advantages of the invention are:
         1—automatic voltage output control during peak demand periods   2—redistribution to the users or to electric power substation available from power plant, for high or medium voltage transmission lines.   3—automatic reduction or increasing voltage output for low voltage transmission lines.   4—automatic remote reading system connected to the electronic control device of the transformer can operate data functions storage.       

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other objects and features of the present invention will become apparent from the following detailed description considered in connection with the accompanying drawing. 
     It is to be understood, however, that the drawing is designed as an illustration only and not as a definition of the limits of the invention. 
       FIG. 1  shows a schematic view of the system according to the invention in a sectional view along lines I—I of  FIG. 2 ; 
       FIG. 2  shows a section along lines II—II of  FIG. 1 ; 
       FIG. 3  shows a sectional view along lines III—III of  FIG. 1 ; and 
       FIG. 4  shows a schematic view of a series connection of the invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIGS. 1 and 2  show schematic drawings showing views of a longitudinal and traversal section of the transformer according to the invention. 
   The transformer comprises a set of parallel iron cores  24  and  24 ′ (only core  24  can be seen in the view of  FIG. 1 ) surrounded by primary winding  7  and secondary winding  18 , (can be seen in the view of  FIG. 3 ). Cores  24  and  24 ′ are connected to external frames  3  and  8  made of non-magnetic material such a PVC or fiberglass. A magnetic shifter  25  is disposed between cores  24  and  24 ′, as shown further in  FIG. 2 . 
   There are non-magnetic rectangular blocks  15 , acting as armor and spacers of the iron cores  24  and  24 ′. Shifter  25  is connected to a shaft  22  that controls the rotation of the shifter. 
   The bar  22  is connected to a motor (not shown). Shifter  25  is comprised of the following components: two semi cylindrical nuclei  13  in overlapped laminated magnetic material, a nucleus support system  16 , and a spring  17  that maintains contact pressure between central nuclei  13  and iron core  24 . 
   Between shifter  25  and cores  24  and  24 ′, there are insulation bars  1  and  2  and an interstice with epoxy resin  4 , and support slabs  14  and  15 , which have the function of support and armor of the semi cylindrical magnetic nuclei  13 , as well as a spacer function from the two parallel iron cores  24 ,  24 ′ of the transformer. 
   The semi-cylindrical shifter  25  rotates clockwise to reduce the power transmission and counter clockwise to increase the power transmission from the primary to secondary winding. 
   The principle shifter operation shown in  FIG. 2 . When the position of shifter  25  is overlapped to the central iron core  24 ,  24 ′, along lines II—II as shown, shifter  25  is positioned at the maximum reduction of power. If the shifter is in the completely not overlapped position, (perpendicular to II—II), (max. reluctance) there is maximum output voltage. 
   The condition of maximum flow intensity passage into the central overlapped lamination (shifter parallel to central iron core) is equal to the reduction of 50 to 60% of the maximum load power; and the condition of minimum flow intensity passage (shifter not overlapped to the central iron core) is equal to the maximum nominal power of the transformer. 
   The rest may be deduced by analogy, because intermediate positions are determined as intermediate reluctance, intermediate power reduction and stabilization, symmetrically to the two parallel iron cores transformers. 
     FIG. 3  shows a schematic drawing of a longitudinal section along lines III—III of  FIG. 1 . There is shown a section of iron cores  24 ,  24 ′ and primary winding  7  and secondary winding  18 . 
   Cylindrical bar  22  is connected to an electric motor support  23 , of an electric motor (not shown) which acts to rotate shaft  22  and subsequently shifter  25  via support bar  26 . 
   Shifter  25  closes the magnetic lamination by rotating, to vary the voltage output in secondary winding  18 . The electric motor support  23  is connected to the external frame  3  and  27  through the external armor  19  and support slab  14 . 
     FIG. 4  is a schematic diagram illustrating hardware elements of the system according to the invention. In this arrangement, there are three coupled transformers. The rotation of each shifter  25  is controlled via microprocessor control  28 . 
   There is a hydraulic cooling oil pump  29  controlled by a drive pump  30 , connected to the microprocessor system, for cooling the system. Each transformer in the system has a voltmeter control  31 ,  32 ,  33  electric motors operating by mechanical connections  23  to shifter  25  of each transformer. The system can be equipped with safety snap-acting limit switches (not shown), external to the cooling oil metal enclosure  43 , which define the rotational limit position of the magnetic reluctance shifter  25 . 
   The transformer includes the group of primary windings in series  37 , 38 , 39 , and secondary windings in series  40 , 41 , 42 , for each iron core  24 . The windings are preferably comprised of braided copper strips, and the number, position, overlapped wiring, square section of braided copper strips, and related dimensions of the iron core, frame and support, spacing insulation electric motor power, shifter dimensions, and metal enclosure, radiator, oil pump, etc. . . ., are not described here and vary by the user&#39;s requirements. The transformer is enclosed in a metal enclosure  43  with cooling oil. 
   There is a radiator  44  with external components  28 ,  29 , 30 , 31 , 33 , 34 , 35 , 36 . The transformer is controlled via remote control  28  which is operated by a microprocessor board with a software program. The system of the coupled transformer inside the metal enclosure  43 , which is filled with mineral oil, is cooled by hydraulic pump  29  connected to a ventilated heat dispenser. The control  30  of pump  29  is achieved by heating sensors controlled with an electronic system  28 . 
   Many different configurations of the windings are possible within the scope of the invention. In  FIG. 4 , the primary and secondary windings are made with three windings each in series, positioned around cores  24 ,  24 ′. 
   Other arrangements are possible as well, such as: 
   1—Primary and secondary winding not overlapped in a symmetrical position around the iron cores: The variation in voltage is achieved by ratio transformation, (V 1 /V 20 ) and wire ratio: (number of turns in primary winding divided by number of turns in secondary winding); 
   For example: primary winding: input 16,000 volt: =(V 1 ) secondary winding: (5,000+35%; or 2,500+35%; or 277+35%; or 120+35%; or 100+35% volt). When the shifter overlaps the cores, the following is achieved: output voltage (V 20 )=(2,500; or 1,250; or 138 or 60; or 50 volts). 
   2—Primary winding partially overlapped to secondary winding, partially positioned in a symmetrical position around the iron core and the remaining windings in symmetrical and separate iron core position. The voltage variation is achieved by constant transformation and shifter variation (shifter reluctance variation); 
   For example: primary winding: input 16,000 volt: =(V 1 ) secondary winding partially overlapped: (3,000; or 1,500; or 200; or 100 volt); plus separate winding not overlapped (2,000+35%; or 1,000+35%; or 177+35%; or 20+35% volt). When the shifter overlaps the cores the following is achieved: output voltage (V 20 )=(2,500; or 1,250; or 138; or 60; or 50 volts). 
   3—Primary winding overlapped to the secondary winding, separate in two, three, four, five or six windings in symmetrical position around the iron core. The voltage variation is achieved by ratio transformation and shifter variation. 
   For example: primary winding: input 16,000 volt:=(V 1 ) separate secondary winding (5,000; or 2500; or 277; or 120; or 100 volts). When the shifter overlaps the cores, the following is achieved: output voltage (V 20 )=(2,500; or 1,250; or 138; or 60; or 50 volts). 
   The three above described winding scenarios will achieve different combinations if connected in series. 
   Accordingly, while only a few embodiments have been shown and described, many variations can be made thereunto without departing from the spirit and scope of the invention. 
   LIST OF REFERENCE NUMERALS 
   
       
         1 —Insulation bar in PVC reinforced with insulating glass fibers, or other non magnetic material. 
         2 —Insulation bar interposed from parallel laminated iron core 
         3 —External frame in PVC reinforced with insulating glass fibers, or other non magnetic material 
         4 —Interstice closed with epoxy resin. 
         5 —Central bar of shifter. 
         6 —Central bar for support of the shifter. 
         7 —Primary or secondary winding, in braided copper strips, or twisted cable 
         8 —External frame in non magnetic material. 
         9 —Base of transformer 
         10 —Connection bar from two laminated iron core nucleus 
         12 —Screw closing the shifter the magnetic overlapped lamination 
         13 —Semi-cylindrical nucleus of shifter in magnetic material, formed from overlapped lamination. 
         14 —Slab of support and armor of semi-cylindrical magnetic nuclei with spacer function in non-magnetic material. 
         15 —Rectangular block with function of armor and insulator spacer in non-magnetic material. 
         16 —Semi-cylindrical support system for variation of the magnetic reluctance 
         17 —Spring for the maintenance of the contact between shifter and laminated iron core. 
         18 —Primary or Secondary winding in braided copper strips, or twisted cable 
         19 —External armor of closing winding in insulated material (insulator spacer) 
         20 —Bar in PVC for closing shifter 
         22 —Shaft of the electric motor. 
         23 —Support bar of the electric motor 
         24 ,  24 ′—Magnetic laminated iron core 
         25 —Socket of positioning for the spring between iron core and shifter of reluctance. 
         26 —Central support bar of the shifter. 
         27 —External support in non-magnetic material for semi-cylindrical magnetic nuclei of shifter. 
         28 —Computer Control 
         29 —Hydraulic Pump for oil cooling 
         30 —Sensor for drive pump 
         31 - 32 - 33 —Voltmeter connection for each transformer 
         34 - 35 - 36 —Sensor for drive motor 
         37 - 38 - 39 —Group of three primary windings in series for each nucleus 
         40 - 41 - 42 —Group of three secondary windings in series for each nucleus 
         43 —Metallic enclosure for cooling oil 
         44 —Forced air radiator for cooling oil or ventilated heat dispenser.