Single machine

In order for a single machine whose length is limited to 10 m to react 1.8 MN requires a very large active area and hence translator radius. These designs can only be discussed if it is assumed there are no limits on the manufacture and handling of PMs. Figure 8.8 shows the parameters of suitable machines with radii varying from 0.4 to

1.5 m and magnet width varying from 0.3-0.8 m.

For the wider magnet geometries there is a point of minimal total mass corresponding to a magnet radius of around 0.5 m. The magnet mass is consistently lower with a reduction in translator radius and utilisation of the maximum available translator length. Reduction of magnet width, however, has a smaller effect as the volume of magnetic material remains roughly constant, simply consisting of more pole pieces to make up the same active area.

Figure 8.8: Many designs of tubular machine

Two alternative examples are highlighted for discussion, corresponding to the minimum radii for magnet widths of 0.8 m and 0.3 m. The former consists of eleven 0.22 m radius magnets weighing 948 kg each and the latter has 28 larger magnets of 0.55 m radius each weighing 2.2 tonnes. These appear to be the smallest magnets which can be used to make a single machine of 10 m stator length capable of reacting the required force.

Handling of these enormous magnets is likely to be troublesome and possibly dangerous. It is hence necessary to investigate using multiple machines of a lower rating.

Renewable Energy Eco Friendly

Renewable Energy Eco Friendly

Renewable energy is energy that is generated from sunlight, rain, tides, geothermal heat and wind. These sources are naturally and constantly replenished, which is why they are deemed as renewable.

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