Patent Application
20170237194
The disclosure relates to field of Power Connectors.
The disclosure generally relates to an electrical terminal contact and, more specifically, to a high power electrical terminal. These types of terminals are used for power distribution and transmission typically found in wind turbines and other high power applications. In these applications, the connection between the conductor and the terminal is done manually on site by highly trained personnel with hydraulic specialized crimping tools. The connectors are permanently deformed onto the cables. This process is slow, requires highly trained personnel and needs certification.
Typically, these type of plug and play high power connectors rely on a terminal structure that includes multi-contact beams, (in the order of tens), in an array. Generally these terminals are cylindrical in shape and include contact beams that are formed inwardly around the interior of the terminal creating a series of single contact points along the periphery of the interface between each beam and a mating terminal pin. Such designs are known to fail due to a cumulative current loading effect. When one point of contact fails, the current load is transferred to the next contact which fails with the extra load until finally thermal runaway occurs and complete failure of the connector occurs.
A connector system is provided that includes a plug connector and a receptacle connector. The connector system is used in high power applications such as power distribution systems including windmill and other power distribution system requiring conductive power lines. The connector system includes a plug having a conductive body with a mounting end and a connecting end. The mounting end is configured for connection to a conductive wire or power transmission line, by crimping the wire to the conductive body. The connecting end is adapted to be connected to a corresponding terminal of the mating connector. The contacting portion includes a round or cylindrical extension for engaging a sleeve portion of the mating connector. The mating connector also includes a mounting end connected to a conductive wire or power transmission line.
The connector system includes a conductive layer positioned between the mating interface of the plug and receptacle connector. The conductive layer includes a contacting ring made from a braid. The braid includes a plurality of individual conductive fibers for creating multiple contact points along the interface. In high current applications, due to resistance, heat buildup can be a potential problem for conductivity. With fewer contact points, the heat buildup can be localized, causing individual contact points to fail which in turn shifts to the next point. In this situation, failure will continue from the first failure point to the second and so forth, until the entire connection fails. In such instances, one can appreciate a high power connector having a novel contacting interface that provides a low resistance contact path.
The disclosure is illustrated by way of example, and not limited, in the accompanying figures in which like reference numerals indicate similar elements and in which:
As described below, detailed embodiments of the disclosure are presented herein; however, and it is to be understood that the disclosed embodiment is merely exemplary of the disclosure, which may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the disclosure. It is to be understood that the disclosed embodiments are merely exemplary of the disclosure, which may be embodied in various forms.
As best shown in
The connection end 64 of the body 80 is constructed in the form of a sleeve 82 having an opening 84 and a pair of slots 86 formed therein. The interior of the sleeve includes a pair of projections 88 formed on the interior surface of the opening 84 of the sleeve 82 and extends around the circular periphery of the opening 84. In the embodiment shown, the projections 88 are shown as circular, but other shapes are contemplated. The slots 86 formed in the side of the sleeve 82 create flexibility in the sleeve 82 allowing for deflection and expansion of the sleeve 82 upon insertion of the mating connector. A clamp 90 is disposed on the exterior portion of the sleeve 82 and placed over the slots 86. The clamp 90 limits the deflection and expansion of the sleeve 82 proving overstress protection and increasing normal force when the connectors are mated together. In the present embodiment, the clamp is made from a higher tensile strength material such as stainless steel, but alternative materials can be appreciated that constrain the sleeve 82 from expanding.
As illustrated in
The plug connector 10 includes a body 20 with a connection end 14 having a circular portion 24 extending from the body 20 along direction A. Although the extension 24 in the embodiment is shown as being circular, other cross-sections are contemplated, such as square, hexagonal and so forth. The extension 24 includes a rounded tip 28 for providing a lead-in when the plug connector 10 is mated with the receptacle connector 60. A contacting ring 40 conforming to the shape of the extension 24, in this embodiment, which is circular, is disposed on the extension 24 and a collar 50 is placed over the extension 24 and retains the contacting ring 50 on the extension 24.
The contacting ring 40, as best depicted in
Once the contacting ring 40 has been positioned on the extension 24 the collar 50 is placed over the extension 24 and translated toward the contacting ring 40. The mounting end 56 of the collar 50 engages the leading edge of the braid 44 of the contacting ring 40 and is crimped or compressed inward, clamping the contacting ring 40 in place. To aid in the assembly, a recess 26 is formed in the extension 24 creating a pocket 26 for the collar 50 to reside. The pocket 26 further locates the collar 50 and the contacting ring 40 in place on the extension 24. This is established during the assembly of the contacting ring 40 and the collar 50 by creating tactile feedback, that is, as the collar 50 is advanced toward the contacting ring 40, the collar 50 is essentially pushed on to the extension 24 and snaps into the pocket 26 as the mounting end 56 of the collar 50 clamps down on the confronting edge of the contacting ring 40. The collar 50 can be further compressed to finally lock down the collar 50 on the extension 24. Additionally, the collar 50 includes a plurality of spaced apart ramps 54 formed on the exterior surface of the collar 50 and these ramps 54 include tapered edges 55, 55′ to further guide the extension 24 of the plug 10 into the sleeve 82 of the receptacle 60 during mating.
The mated assembly is illustrated in
As best illustrated in FIG, 13, upon complete mating of the plug 10 to the receptacle 60, electrical contact between the connectors is made through the contacting ring 40. As shown, the projections 88 formed on the sleeve 82 are disposed directly on the braid 44 of the contacting ring 40. Due to the biasing effects and the resiliency of the sleeve 82 combined with the added stiffening of the clamp 90, the projections 88 protrude into the braid 42. The construction of the braid 44 permits the individual conductive fibers 42 to shift and allows the fibers 42 to conform to the shape of the projections 88 that are in engagement with the braid 44. In this instance, the braid essentially surrounds the projections 88. Once mated, the current passes from the cable 70 through the female socket 80 and sleeve 82 and is evenly distributed across the many points of contact created by the braid 44 and contact between receptacle connector 60 and the extension 24 of the plug connector 10.
In an alternative embodiment (not shown), the extension of the plug connector may include a step portion, that is, the extension will have an additional portion that has a smaller diameter. In this embodiment, the connector assembly will include two electrical interfaces that utilize a contacting ring. Each contacting ring will be size appropriately for each stepped portion of the extension. The receptacle connector includes a stepped sleeve that is matched with the corresponding stepped portion of the extension. In this embodiment, there is a second electrical interface that can divide the current passing through the connector system even further. The process of splitting the current over hundreds of points of contact reduces Joule heating of the connector. The braid interface length also minimizes the Joule heating process. The braid length is less than 1mm. For example a 1000 Amp load can be split into more manageable loads of 5A across the braid interface. A section through the braid interface is depicted in
As shown in
The design of the embodiment shown improves upon Louvertac bands 140 by providing a lower Resistance (bulk braid) which reduces the overall resistance.
If it is assumed that current travels from the center of the circular cross section through the strands and into the outer sleeve, then the distance it must travel through the braid strands is very small as shown in
Other factors with this electrical interface that must be considered are increasing the braid pitch reduces the quantity of parallel paths for current flow which increases the electrical resistance and resultant Joule heating. The reduction in strand quantity increases the thermal resistance of the connector. The combined thereto-electric effect increases the temperature of the braid interface. Increasing the contact force reduces the interface electrical resistance by increasing the contact area available to the braid and terminals. This reduction in resistance reduces the Joule heating of the device and overall temperature rise of the interface. The connector design should minimize Joule heating by having a copper braid material of maximum strand diameter, tightly packed strand-to-strand pitch, have a plating surface coating with high thermal and electrical conductivity-to-hardness ratio, (silver is optimum for this situation), and as high a contact force as possible, taking account of braid damage, applied to each strand.
The above description illustrates a connector assembly system for a wire to wire connection system. The system is shown as a single wire conductor to a single wire conductor with a connection element in the form of a pin and socket. The pin and socket are exposed and the conductive body portions of the plug and socket can be accessed without any insulative barrier. In other embodiments utilizing the above described high power connection system, insulative housing are incorporated.
In general, the connector system includes a pair of cooperating housings molded from an insulative material. The housings include a cavity formed through the housing that retains respective ones of the plug connector or the receptacle connector and include an interface for joining the housings together and providing a pass through opening so the plug and receptacle can be mated providing the electrical connection. The housings may also include a locking feature disposed across the interface providing a positive connection between the housing that prevents separation of the connectors in normal operation. The housings are generally molded from plastic and are rigid by nature; other housings made from elastomeric materials such as rubber can also be appreciated. These materials provide the necessary insulative barrier but also allow for a certain degree of flexible. In large scale connector systems this can provide additional strain relief and ease in handling.
It will be understood that there are numerous modifications of the illustrated embodiments described above which will be readily apparent to one skilled in the art, such as many variations and modifications of the compression connector assembly and/or its components including combinations of features disclosed herein that are individually disclosed or claimed herein, explicitly including additional combinations of such features, or alternatively other types of contact array connectors. Also, there are many possible variations in the materials and configurations.
This application claims priority to U.S. Provisional Application No. 62/037,353, filed Aug. 14, 2014 which is incorporated herein by reference in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US15/45027 | 8/13/2015 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62037353 | Aug 2014 | US |
