Abstract:
The invention relates to a power capacitor for use in capacitor banks, which is build into a housing and interconnected by ribbon cables. The capacitor and ribbon cable are interconnected using plug-in functional elements which are mounted on the housing and into which contact arranged on the ribbon cables are inserted

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of copending international application PCT/DE99/01017, filed Apr. 1, 1999 which designated the United States. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to the field of capacitor banks and more particularly to an arrangement and method for connecting capacitor components to the capacitor bank boards. The connection is effected such that the capacitor components are securely held in place in an secure and modular manner while electrical connection between the components and board is maintained. 
     2. Description of Related Art 
     Condenser banks and capacitors therefor are well known in the art as exemplified by European patent EP 0 450 122 B1. Herein, the capacitors are affixed to a printed circuit board via connecting bolts and nuts and/or solder. The development of these power condensers is directed towards improved inverters and semiconductor valves. Additional applications for power condensers is with IGBT (insulated gate bipolar transistor) semiconductors. The capacity of the capacitor banks ranges from about 100 kilowatts to upwards of 6 megawatts. An additional application for the banks is with rectifiers wherein some success has been achieved through reduction of capacitor component size and lowering of parasitic inductance therebetween. However, the related art applications do not have the modular compactness sometimes desired in the industry, nor the possibility of plugging modular capacitor components onto the capacitor bank boards where such elements are securely held in place and power flows via the connection between component and board. Such possibility simplifies the connection, as no solder and/or nuts and bolts are necessary, thereby reducing engineering and manufacturing costs while increasing design possibilities. 
     BRIEF SUMMARY OF THE INVENTION 
     It is accordingly an object of the invention to provide an improved modular arrangement for connecting capacitor components, such as condenser batteries, to boards forming capacitor banks. It is a further object to provide an arrangement which can be implemented so as to enable mass production at reasonable engineering effort and expense and with maximally replicable component characteristics. It is a further object that the capacitor components are snap fitted and/or plugged into the board. It is a further object that the connection be sufficient to facilitate electrical communication of various power levels, as may seem fit to the ordinary designer, between component and board. It is a further object to reduce parasitic inductance and lower resistance in the connection of the components and board. (spread out contacts) 
     With the foregoing and other objects in view there is provided, in accordance with the invention, an arrangement for attaching at least one capacitor component and a printed circuit board, said arrangement comprising at least one blade contact for conducting electrical power, said blade contact formed by an elevated conductor end of a conductor accommodated by said board; and a number of connection members for effecting electrical communication with said blade contacts, said members formed within said at least one capacitor component and having a housing comprising a cavity and opposing contact leads for receiving said blade contacts therebetween such that said blade contacts are securely held and electrical contact between said blade contacts and said opposing contact leads is maintained. 
     In addition, the present invention includes a method of attaching a capacitor component to a board comprising the step of plugging a blade connector formed from an elevated conductor end of a conductor housed within said board, into a pair of opposing contact leads within a receiving member which is further formed within said capacitor component, such that said blade connector is snapped fitted between said contact leads and electrical contact is established between said blade connector and receiving member. 
     The invention is explained in greater detail below by reference to exemplary embodiments shown in the drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 depicts a side view of a capacitor component; 
     FIG. 2 depicts a top view of a capacitor bank board, 
     FIG. 3 depicts a cross sectional view of the capacitor bank board; 
     FIG. 4 depicts another cross sectional view of the capacitor bank board; and 
     FIG. 5 depicts an enlarged view a modular connection element. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     Reference is now made to the figures of the drawings in which elements that are identical or that function identically are identified by the same reference numerals throughout. FIG. 1 depicts a capacitor case  1  having a plurality of condensers (not shown) built therein. The case includes two modular connection members  5 . The actual number of modular connection members may vary by application as would be appreciated by one skilled in the art. An enlarged view of the modular connection member is depicted in FIG. 5, which is discussed in more detail below. 
     FIG. 2 depicts a top view of a capacitor bank board  20 . The board includes a flat conductor  2 . The conductor  2  is designed and implemented, as is known to one skilled in the art to facilitate communication of power with the board and components thereon and/or therein. The flat conductor includes raised ends forming blade contacts  6 . The broken line  22  depicts condenser battery case  1  as it would appear plugged into board  20 . 
     FIG. 3 depicts a cross section of board  20  featuring ribbon cable or conductor  2  and blade contacts  6  which facilitate the communication of electrical power from an attached component to other components accommodated on or within the board. The blade contacts may be stamped out or effected in other ways envisioned by the skilled artisan. 
     FIG. 4 depicts another cross sectional view of board  20  featuring a second lateral view of blade contacts  6 . The contacts may be formed to include a recess  9 . The recess is shaped so as to receive a mating protrusion  12  of a first contact lead  10  of a component connection member. The recess and protrusion cooperate so as to securely hold a first contact lead  10  against blade contact  6  so as to further facilitate the communication of electrical power therebetween. Arrows  14  indicate the movement direction of first contact lead  10  and blade contact  9  when the two are brought together. By this arrangement, blade contact  6  can be snapped and held in place by the cooperation of recess  9  and protrusion  12 . The number of protrusions and recesses are limited by design choice provided the number of each is equal. A second contact lead  7 , which acts similarly to first contact lead  10 , is also depicted. 
     FIG. 5 depicts an enlarged view of connecting member  5 . Connecting member  5  includes a pair of opposing first and second contact leads  10  and  7  respectively. The contact leads cooperate to resiliently accommodate an element therebetween. Such an element may include the blade conductor  6 . First and second contact leads may further include at least one contact point  8  extending in between the two contact leads. The contact points may be opposing and identical in shape and composition. The contact points facilitate communication of electrical power with the blade contact  6  or any other element accommodated by the connecting member  5 . The contact leads may also include at least one protrusion  12  spaced about the contact leads so as to receive a mating recess such as recess  9 . The protrusions cooperate with mating recesses so as to snap fit an element, such as the blade contact, between the two contact leads. The contact leads, protrusions, and contact points are manufactured according to means known to one skilled in the art. 
     The connecting members are depicted (FIG. 1) at opposite ends of a capacitor case. By spacing the connecting members, parasitic inductance is reduced. Likewise, with the blade contacts having a short length sufficient for accommodating within the connecting members, board space is optimized for connection of additional condenser batteries and the like. The short length blade conductors have been shown to facilitate a rectifier inductance of less than 100 nanohenries. Furthermore, the cases can be attached in parallel such that when applied to rectifiers, inductance is reduced accordingly: L rectifier ˜(1/n cond )+L system  where n cond  is the number of connected condensers. 
     A method of implementing the above arrangement includes snapping and/or plugging a component, such as the condenser battery, to a board, such that the blade contacts are accommodated and securely held within the connecting member  5 . The actual number of pairs of blade contacts and connecting members is a matter of design choice ranging from at least two to preferably four to six pairs per component. The preferred number has been demonstrated to effectively reduce parasitic inductance with operational current at, for example, 200 A per condenser. 
     The modular plugging and/or snapping arrangement is a simplification over prior connection methods with regard to number of necessary components parts and installation costs. Likewise, the current arrangement and method facilitate design choices regarding the number of condensers or other snapped on or plugged on components. An advantage of cooperating blade contacts and contact leads is that no additional elements or parts are needed with respect to making the conductor accessible to external components thereby reducing engineering and manufacturing costs while increasing design possibilities. 
     The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications would be obvious to one skilled in the art are intended to be included within the scope of the following claims.