Brief introduction of DC Panel Mount Cable
DC Panel Mount Cable is a power cable used in DC power transmission and distribution systems. The structure of DC Panel Mount Cable is basically the same as that of AC cable except that the electrical characteristics of operation are different from AC. DC Panel Mount Cable is mainly used for long-distance submarine cable lines.
The DC power transmission and distribution system usually runs on two wires (positive and negative), so the DC Panel Mount Cable is generally a single-core cable. Because the conductors of the DC Panel Mount Cable have no skin effect and proximity effect, it is not necessary to use a complex split conductor structure even if a large current is transported. The insulation of the DC Panel Mount Cable can be the same as that of the oil-impregnated paper insulated cable, the solid extruded polymer cable, the self-contained oil-filled cable, and the gas-filled cable, and the armor layer does not need to be considered because it is not affected by the conductor current. Layer loss and measures to reduce armor resistivity.
The maximum field strength of the AC cable is always close to the insulation layer on the conductor surface, while the electric field strength of the DC Panel Mount Cable is proportional to the resistivity of the insulation. The resistivity of the insulation changes with temperature, that is, the insulation layer. The maximum electric field strength in is not only related to the applied voltage, but also to the load. When there is no load, the maximum electric field strength is at the surface of the cable conductor. When the load increases, due to the higher temperature near the conductor, the insulation resistivity decreases, the electric field strength on the conductor surface decreases, and the electric field strength on the insulating surface gradually increases. Therefore, the maximum allowable load of the DC Panel Mount Cable should not make the electric field strength on the insulating surface exceed its allowable value, that is, not only the maximum working temperature of the cable, but also the temperature distribution of the insulating layer should be considered.
Another feature of the DC Panel Mount Cable is that the insulation must be able to withstand rapid polarity reversals. The polarity reversal under load will cause an increase in the electric field strength within the insulation, usually by 50% to 70%.