Design of Mine Underground Power Distribution
The design of mine underground power distribution system is very important for the safe operation of the mine, especially for underground coal mine. The design of mine underground power distribution to meet the needs of coal mine production and the safe use of power supply, the availability of a reasonable power supply system plays a crucial role in the coal mine production, so reasonable design of the mine underground power distribution system is the guarantee for safe and reasonable use of power in coal mine.
The mine underground power distribution design should be considered from three aspects of operational requirements, equipment selection, and network design. Operational requirements include internal and external electrical power supply requirements, circuit power distribution requirements, and environmental protection requirements. A comprehensive assessment of the above-mentioned operational requirements can provide theoretical guidance and technical basis for the reasonable allocation of the overall power distribution program of the coal mine.
Equipment selection is a major content of the design of underground power distribution system. In the case of reasonable design and meet the requirements of power supply, the selection of appropriate power equipment should also consider the advantages of types already in use, mostly metal enclosed switchgear and switchgear used in aseismic classes, flexible power cables, as well as equipment for requirements for seismic, fire prevention, and corrosive environment.
In the mine underground power distribution system design, the most important part is the network design. Network design includes the composition of the system route and the selection of its power distribution parameters. The system route drawings should be divided into two major components: field line and connection line. In order to prevent interference and improve the reliability of power supply, the line selection and design should meet the requirements of normal voltage drop and voltage deviation, and balance loading. Power distribution parameters include step-down volume and capacity parameters and step-up volume and capacity parameters.
The voltage drop of the line should be controlled within 10% of its rated voltage, while the voltage deviation should not exceed 5% between each line. When selecting the capacity of transformer, the special requirements of loads should be considered, and the capacity should generally be selected based on the maximum current of the phase, 2.5 times the average current and 2 times the maximum short circuit current of the motor.
To sum up, the design of mine underground power distribution is very important for safe operation of underground coal mine. The design should be based on operational requirements, equipment selection, and network design. On this basis, the network route, capacity selection and other parameters should be reasonably matched to ensure the safe running of power supply system in coal mine.
