The Emerging Electrical Markets for Copper
Market Forecasts by Sector
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- Figure 119: Forecast Motor Market, Defined by Copper Content (Kt Cu)
- The Impact on Copper
- Figure 120: Forecast CMR and Shaped Copper Conductor Motor Markets for Copper (Kt Cu)
Market Forecasts by Sector As the main market for winding wire, motors form a huge market for copper. With the requirement for higher efficiency standards, it is reasonable to assume that there will be some increase in copper content for any given power rating. As we shall see below in “The Impact on Copper” section, however, this is not necessarily assured. As well as altering the specification of motors when they are replaced at the end of their life cycle, or where newly introduced, it is likely that there will be some replacement before end of life. The evident improved economics of modern motor and drive systems may lead to some earlier replacement, thus boosting the size of the motor market in coming years. A market forecast for motors measured in terms of copper content is presented below. It is based on the following simplifying assumptions: The size of the motor market will relate directly to GDP, except for traction motors in vehicles where copper use will be in line with that shown in Section 2. The reduced share of heavy industry as a share of total GDP would mean that, without any positive influence on the market, the motor market would fall by 0.25% p.a. in relation to GDP. Higher motor efficiency, largely enforced by legislation, will result in a 0.5% p.a. rate of growth in copper use for any given output of motors (excluding traction motors in vehicles). Advanced replacement of motors to voluntarily meet higher energy efficiency standards will lead to an additional 0.25% p.a. growth in the size of the motor market. It can be seen that point 3) presupposes some increase in the average copper content of motors. This does not necessarily mean a “new” motor market, as the increase may be achieved by putting more copper wire in the stator windings, for example. If new designs with high content are successful, then it is possible that the rate of unit increase in copper content could be higher than that forecast. On the other hand, low copper technologies may lead to a slightly lower rate of increase. The relative market positioning of high and low copper solutions is discussed below in “The Impact on Copper” section. Figure 119: Forecast Motor Market, Defined by Copper Content (Kt Cu) 
The Impact on Copper While the trend towards greater motor efficiency is certain, the way in which this will be accomplished is not. There is more than one way in which higher motor efficiency can be achieved, with different implications for copper content and especially for what may be defined as new markets for copper. Greater efficiency is achieved by reducing energy losses. These losses fall into several different categories: Electrical losses due to electrical resistance of the windings, conductor bars, and end rings. Magnetic losses due to hysteresis and eddy currents of the magnetic field in the steel laminations. Stray load losses due to imperfections in the flux (leakage, harmonics, irregularities, etc.). Mechanical losses due to friction. Brush contact losses. Percentage energy losses increase when the motor’s load is further away from its nominal value. The most significant losses are electrical and stray load losses. The technical solutions available to decrease these losses include: Reducing the electrical losses in the windings, by increasing the cross sectional area of the conductor or by improving the winding technique. Reducing the magnetic losses by using better magnetic steel. Improving the aerodynamics of the motor to reduce mechanical losses. Minimizing manufacturing tolerances. Using an electrically commutated system to eliminate brush contact losses. Using a Variable Speed Drive (VSD) if the motor operates regularly at other than its nominal speed/ torque. The above list makes it clear that there are several options for improving efficiency that do not require larger amounts of copper. Improving manufacturing tolerances and simply reducing aerodynamic losses through improved design can reduce losses without any necessary alteration to material content. Rather than focussing on copper, a manufacturer may choose instead to focus on the quality and content of magnetic steel. In comparison with copper, magnetic steel is very cheap. Amongst the high copper options, we identify the following: Use die-cast copper conductor bars and end rings for induction motors. Die cast copper motor rotors (CMR). Use copper rotors in permanent magnet and water cooled high frequency induction motors with applications with high torque to weight ratio. Increased packing weight in stator windings (to plus 80% in comparison with standard 50-60%). Early developments in motor efficiency focussed on reducing electrical losses by increasing the packing weight of stator windings. This is logical, as electrical losses typically account of more than half of all energy loss, and stator losses around two-thirds of electrical loss. A high efficiency motor will usually have 20% more copper in the stator winding than its standard counterpart. The disadvantage of increasing efficiency through higher packing density is an increase in motor size, and expense (especially at today’s copper price). The size issue is an important one in many motor applications, especially consumer appliances, but also applying to the automotive market. A developing product, the shaped copper conductor motor, currently in development, promises to overcome this difficulty. Rather than round wire, square or hexagonal wire allows the air spaces in the stator to be reduced, thus allowing a motor of a given rating to be smaller. While attractive, however, technical difficulties in both ensuring good adhesion of enamel to the wire and in winding itself mean that commercial development of the shaped copper conductor motor is some way off. It may be the case that shaped copper conductor motors will be an expensive option. As tight wire packing is alternatively achieved by drawing wire much finer, however, it could prove to be a relatively cheap option. In Figure 120 we present forecasts for shaped copper conductor motors based on the assumption that this technology is commercialised around 2015 and that it finds an important market niche in small to medium sized motors in applications where there is a space constraint. Rather than focussing on the stator, improving the material or configuration of the rotor can offer substantial efficiency gains. Rotor losses (also called slip losses) are another form of electrical loss. They are caused mainly by the difference in rpm between the rotational speed of the magnetic field and the actual rpm of the rotor and shaft at a given load. Rotors are typically made of die-cast aluminium. Electrical efficiency of the motor can be improved by replacing aluminium with copper. The problem with doing this is that, because of the high temperature required, copper is difficult to die-cast. This problem has been overcome, and there are now significant numbers of copper motor rotor (CMR) motors in production. The advantages claimed for CMR motor on a like-for-like basis are as follows: Improvement in motor energy efficiency rating of 1-5%. Reduction in motor weight. Reduction in overall manufacturing cost. Figure 120: Forecast CMR and Shaped Copper Conductor Motor Markets for Copper (Kt Cu) 
Some of these advantages may be disputed, however, especially manufacturing cost. As it stands, few manufacturers have been prepared to take on the heavy capital cost of creating CMR capacity, without assured sales. If they do invest and the capital cost is offset with volume sales of CMR motors then it may be that unit motor cost is quite low. This is far from assured. The penetration of CMR motors is mainly in low voltage industrial motors of 1 to 100 kW. The current sales are thought to be around 175,000 units per year of a 30 million motor market. There is a potential market for CMR motors are in other applications, especially small fractional horsepower applications, which has not yet come to fruition. There is some debate over whether or not CMR is also a suitable option for hybrid and electric vehicles. Production hybrids to date have tended to favour permanent magnet motors, a low copper option without copper stator windings. More conventional copper motors, some with copper rotors, have been more prominent in early pure electric vehicles. This is certainly a market patch to be fought over. As well as efficiency, however, the CMR motor will have to compete on grounds of cost, weight and size, and is not expected to fare particularly well. Taking account of its advantages and also the ambivalent attitude of much of the market to CMR, our forecast for this motor type is presented in Figure 120. While there are some big positives in the motors business, it would be unbalanced to avoid mentioning a potentially important negative development. In coming years, we expect to see a large scale commercialisation of copper clad aluminium (CCA) winding wire in coming years. CCA demonstrates similar electrical characteristics to pure copper wire. To date, CCA has had a mixed reception, largely because of the production of low quality product in China. With today’s large copper vs. aluminium price differential, however, it should be possible to produce CCA motors significantly cheaper than copper ones. These will contain, at most, 10% copper in the winding wire. CCA motors are likely to have their greatest application in small and medium sized motors where space constraint is not a pressing problem. Directory: wordpress -> wp-content -> uploads -> 2017 uploads -> Professor rona s beattie and dr david bamaung glasgow caledonian university email for corresponding author uploads -> Best Offensive Players: qb #19 keenan reynolds, N, ’16. Lg #57 E. K. Binns, N, ’16 uploads -> Smart Supervision Research Partner Orientation Course fy13 and fy14 Grantees September 29- october 1, 2015/San Antonio, tx uploads -> Autonomous Control for a Reliable Internet of Services (across) 2017 -> 6 Thai Market Analysis 2017 -> Birchwood intermediate school 2017 -> Operation corporate 2017 -> This document is written for the amateur radio operator that will be using the PiGate as an emergency communications device in a disaster situation Download 10.26 Mb. Share with your friends:
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