Application of Copper
Electrical Industry
Power Transmission
Power transmission requires a large amount of copper with high conductivity, which is mainly used for power wires and cables, buses, transformers, switches, plug-in components and connectors.
In the process of power transmission of wires and cables, electric energy is wasted due to resistance heating. From the perspective of energy saving and economy, the "optimal cable cross-section" standard is currently being promoted in the world. The popular standards in the past were simply based on the perspective of reducing the investment in one-time installation. In order to minimize the cable cross-section, the minimum allowable size of the cable was determined to prevent dangerous overheating under the rated current required by the design. Although the installation cost of the cable laid according to this standard is low, the resistance energy consumption is relatively large during long-term use. The "optimal cable cross-section" standard takes into account both the one-time installation cost and the power consumption, and appropriately enlarges the cable size to achieve the purpose of energy saving and the best comprehensive economic benefits. According to the new standard, the cable cross-section is often more than doubled than the old standard, which can achieve an energy saving effect of about 50%.
In the past period of time, due to the shortage of steel in my country, aluminum was used to replace copper in overhead high-voltage transmission lines in the hope of reducing weight, considering that the specific gravity of aluminum is only 30% of that of copper. Underground cables. In this case, aluminum pales in comparison with copper due to its poor conductivity and large cable size.
For the same reason, it is also a wise choice to replace the old aluminum winding transformer with energy-saving and efficient copper winding transformer.
Motor manufacturing
In motor manufacturing, high-conductivity and high-strength copper alloys are widely used. The main copper parts are stators, rotors, and shaft heads. In large motors, the windings are cooled with water or hydrogen, which is called double water internal cooling or hydrogen cooling motors, which requires a long length of hollow wire.
Motors are large users of electricity, accounting for about 60% of the total electricity supply. The cumulative electricity bill for the operation of a motor is very high, generally reaching the cost of the motor itself within the first 500 hours of operation, equivalent to 4 to 16 times the cost within a year, and can reach 200 times the cost during the entire working life. A small increase in motor efficiency can not only save energy, but also achieve significant economic benefits. The development and application of high-efficiency motors is a hot topic in the world today. Since the energy consumption inside the motor mainly comes from the resistance loss of the winding, increasing the cross-section of the copper wire is a key measure to develop high-efficiency motors. Compared with traditional motors, the use of copper windings in some of the first developed high-efficiency motors has increased by 25% to 100%. The U.S. Department of Energy is funding a development project to produce motor rotors using cast copper technology.
Communication cables
Since the 1980s, due to the advantages of large current carrying capacity of optical fiber cables, they have been rapidly replaced by copper cables on communication trunk lines. However, a large amount of copper is still needed to convert electrical energy into light energy and input lines to users. With the development of the communications industry, people are increasingly dependent on communications, and the demand for optical fiber cables and copper wires will continue to increase.
Residential electrical lines
As the living standards of our people improve, household appliances are rapidly popularized, and residential electricity loads are growing rapidly. As shown in Figure 6.6, in 1987, the residential electricity consumption was 26.96 billion kWh (1 kWh = 1 kilowatt-hour), and ten years later in 1996 it soared to 113.1 billion kWh, an increase of 3.2 times. Despite this, there is still a big gap compared with developed countries. For example, in 1995, the per capita electricity consumption in the United States was 14.6 times that of my country, and Japan was 8.6 times that of my country. There is still a lot of room for development in the future for my country's residential electricity consumption. It is expected to increase by 1.4 times from 1996 to 2005.
