Mine power cable with control and monitoring equipment

Abstract

This utility model relates to the cable industry, particularly power mine cables. The technical result consists of increasing cable reliability by enabling damage monitoring during operation, cable operation management, and the transmission of information signals from mining equipment. The cable comprises three main copper rubber-insulated conductive conductors shielded with semiconducting rubber, insulated auxiliary conductors, a bare ground conductor, a two-layer outer sheath, and a monitoring conductor between the layers of the outer sheath. The monitoring conductor, consisting of strands, also contains a fiber-optic module. 2 c.p. f-ly.

Description

[0001] The utility model relates to the cable branch of the electrical industry, can be used in the mining industry and is intended for stationary and mobile installation in the open air, as well as for connecting to the electrical network of mine drilling tools, mobile machines, mechanisms or electrical installations operating in the cleaning and development faces of mines and pits. The cables are designed to operate at a voltage of 660 V or 1140 V (0.6 / 1 kV) AC with a frequency of 50 Hz on the main cores, while the voltage of the auxiliary cores is 220 V AC with a frequency of 50 Hz, and at a voltage of 3300 V (1.8 / 3 kV) AC with a frequency of 50 Hz on the main cores, while the voltage of the auxiliary cores is 380 V AC with a frequency of 50 Hz.

[0002] The closest analogue (prototype) is known from the prior art - a flexible heat-resistant shielded power cable, containing three main copper insulated conductive cores of increased flexibility with elastic conductive screens, copper auxiliary cores in rubber insulation and a split grounding core, twisted around a profiled core, with an internal screen made of conductive rubber along the twist of the cores, with inner and outer sheaths made of rubber, characterized in that between the inner and outer sheath there is a monitoring core located concentrically to the cable axis (patent RU No. 211321 "Flexible power cable with a monitoring core", IPC H01B9 / 02, published on 31.05.2022).

[0003] The common elements of the claimed utility model and the prototype are the purpose and scope of application of the flexible power cable - a mine cable for the mining industry, the main elements of the cable design.

[0004] The difference between the declared utility model and the prototype is the absence of a common screen along the twisted wires and a different design of the monitoring wire.

[0005] The task that the declared technical solution is aimed at solving is to expand the arsenal of mine cables operating in a wide range of operating voltages from 1140 V to 6000 V and possessing high operational reliability due to the use of control and management tools in the cable design.

[0006] This task is achieved due to the fact that the flexible mine power cable contains three main copper rubber-insulated conductive cores, shielded with semi-conductive rubber, insulated auxiliary cores, an uninsulated grounding core and a two-layer outer sheath, while between the layers of the outer sheath there is a monitoring core, one of the strands of which is a fiber optic module with an attenuation coefficient of no more than 0.8 dB / km at a wavelength of 1300 nm, and the monitoring core itself is made by the winding method; or made in the form of a braid of copper or tinned copper wires; or in the form of a combined braid; or in the form of a winding of copper or tinned copper wires and synthetic threads, or copper or tinned copper and steel wires.

[0007] The technical result provided by the given set of features is the ability to monitor cable damage during operation, control the cable operation process, transmit information signals from mining equipment and, as a result, increase the reliability of cable operation.

[0008] Mine power cables, due to their long lengths and harsh operating conditions, are among the most vulnerable and dangerous elements of underground power grids. Constantly moving along working faces behind machinery, they are frequently damaged by rock strikes, vehicle collisions with crushed insulation, impact loads, cyclic loads, conductor breaks, tensile stress, and exposure to aggressive environments. They account for 40% of accidents. High cable damage is one of the main causes of explosive mine atmospheres, fires, and electric shocks. Therefore, mine cables are subject to stringent operational requirements. The cable design must ensure that if the outer sheath is damaged (crushed or crushed), the cable is disconnected (voltage removed) before the insulation of the main conductors is damaged, short-circuiting, or sparking occurs.

[0009] Reducing the incidence of cable line failures is only possible through the implementation of continuous monitoring systems that can monitor the insulation condition of cable lines in real time. Only such systems can promptly detect rapidly developing defects at the earliest stages, thereby promptly preventing potential cable line emergencies. By connecting the monitoring core to various diagnostic equipment, cable line faults can be effectively and promptly troubleshooted. Furthermore, the monitoring core, made as a winding of copper or tinned copper wires, or as a combined winding of copper or tinned copper wires with synthetic threads, or a combined braid of steel wires with copper or tinned copper wires, provides additional protection for the cable from mechanical damage, thereby acting as armor within the cable.Fiber optic cables are also used to ensure continuous monitoring of cable parameters, to identify faults in the power system that could lead to cable failure, to promptly resolve these issues, and to transmit information about the operation of mining equipment. Typically, power transmission and distribution cables and data transmission cables are located separately, but with the large number and size of equipment, space for cables is increasingly limited. Therefore, the proposed combined cable design is optimal for a mining cable, combining the primary function of transmitting electricity to equipment with the transmission of information from control and monitoring systems located within the cable itself.Furthermore, the combination of two information sources (the monitoring core and the fiber-optic module) in this control and monitoring system, in addition to saving space, provides the most complete and reliable information on both the cable's condition during operation and the transmission of essential information on the mining equipment's operation, with data transmitted to the dispatcher's sensor. The fiber-optic modules use optical fibers with an attenuation coefficient of no more than 0.8 dB / km at a wavelength of 1300 nm. These fiber-optic modules, being lightweight, compact, and highly sensitive, can monitor parameters over distances of up to several kilometers, while being immune to electromagnetic interference and completely explosion- and fire-proof.The simultaneous use of both control and management tools in the cable design (monitoring core and fiber-optic module) is performed for more reliable measurement of cable parameters, their interchangeability in the event of damage to one of them, obtaining the most complete information picture during the operation of the cable and mining equipment, and for transmitting information signals about the operation of the equipment to the dispatcher's sensors.

[0010] The conductive cores and the grounding core of the cable are made of flexible copper wire or copper wire tinned with tin or lead-tin alloy. The grounding core is uninsulated, but an additional screen of conductive rubber may be applied to it and to the auxiliary cores. The auxiliary cores of the cable are located either in the interphase space of the main cores or in the center of the cable. In this case, various options for the relative position and twisting of the main cores with the auxiliary cores and the grounding core are possible. Insulation is single- or double-layered, made of ethylene-propylene rubber. The outer sheath of the power mine cable is double-layered, either made of oil- and petrol-resistant, ozone-resistant, flame-retardant rubber; or thermoplastic polyurethane; or polyvinyl chloride plastic compound; or thermoplastic elastomer.Between the layers of the outer sheath is a monitoring core, either made by winding or braiding copper or tinned copper wires, or a combined braid or winding of copper or tinned copper wires and synthetic threads, or copper or tinned copper and steel wires. A fiber optic module with an attenuation coefficient of no more than 0.8 dB / km at a wavelength of 1300 nm is used in place of one of the strands of the monitoring core.

[0011] Cable production is based on established cable equipment and standard technologies. The manufacturing process includes copper wire drawing on drawing machines, conductor stranding on stranding machines, rubber insulation application on continuous vulcanization units, profiled core production on an extrusion line, and the overall stranding of the main, shielded, and auxiliary conductors with a ground conductor on stranding machines. Braiding is performed on braiding machines, the monitoring conductor is applied on a stranding machine, and the sheathing is applied on continuous vulcanization units.

Claims

1. A flexible mine power cable containing three main copper conductive cores insulated with rubber, shielded with semi-conductive rubber, insulated auxiliary cores, a non-insulated grounding core and a two-layer outer sheath and a monitoring core between the layers of the outer sheath, characterized in that the monitoring core, consisting of strands, also contains a fiber-optic module.

2. A cable according to paragraph 1, characterized in that the monitoring core is made by winding or is made in the form of a braid of copper or tinned copper wires, or in the form of a combined braid or winding of copper or tinned copper wires and synthetic threads, or copper or tinned copper and steel wires.

3. The cable according to paragraph 1, characterized in that the fiber optic module has an attenuation coefficient of no more than 0.8 dB / km at a wavelength of 1300 nm.