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environment, it is also vital that cables continue to work despite corrosion caused by spraying of chemical agents such as acids or lubricants. Here again, a good knowledge of the properties of the materials and of an optimized implementation is essential.
Axovolt miniature high voltage cable assemblies, manufactured by Axon' Cable, are designed up to 12 KV DC for a maximum altitude of 21,000 m. They are intended for applications with reduced atmospheric pressure. They combine bulk and high voltage constraints. Conductor construction and insulation thickness play an essential role in limiting partial discharges by avoiding roughness, spikes, or frayed wires. The use of a semiconductor layer makes it possible to limit partial discharges by distributing the electric charges homogeneously on the surface of the conductor.
Vibraflame Cable , designed by Axon' Cable, is insulated with a combination of mica, organic polymers, and fiberglass. It is fire resistant and unable to propagate a flame. It creates a thermal barrier that protects the conductor and maintains electrical characteristics while being flexible. In a fire, Vibraflame maintains the integrity of the electrical circuits for a minimum of four hours.
Protecting links from partial discharges
In the case of high-voltage cables, it is vital to avoid partial discharges. This electrical phenomenon occurs when the electric field becomes intense enough to ionize the surrounding air and the air inside the cable (around conductors, for example). Breakdown, energy loss, and wear of the insulation of the cables are possible consequences. In order to avoid partial discharges, it is possible to simulate the electric field lines. By selecting the nature of the insulating material and therefore its permittivity, i.e., the ability of a material to store electrical energy when exposed to an electric field, the risk of breakdown is reduced. For example, PTFE has a permittivity of 2.1 and PEEK has a permittivity of 3.1. A lower permittivity implies a lower electric field in the surrounding air. The risk of partial discharges is to be taken into account particularly at the cable-connector transition, or between two connections with the addition of splices (junction elements). The challenge is to avoid the reinforcement of the electric field, which could lead to the appearance of partial discharges. For aeronautical applications, the atmospheric pressure being reduced with altitude, partial discharges occur at a lower voltage than on earth.
Combining constraints
In harsh environments, interconnect solutions face multiple constraints such as temperature extremes, humidity, exposure to chemicals, radiation, vibrations and shocks. To ensure the reliability, performance, and resistance of the system, these solutions have to combine properties that sometimes appear to be at odds. As an example, for the nuclear and research markets, interconnect solutions must meet the strictest requirements in terms
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