Figure 3.3: Conventional linear PM machine

Figure 3.3: Conventional linear PM machine

As the translator moves, so too does the flux pattern resulting from the presence of magnets. An emf is hence induced in the stationary coils as the flux cutting them is changed. The flow of magnetic flux can be simplified by assuming infinitely permeable iron, in which case the total magnetomotive force (mmf) produced by a magnet is dropped across the magnetic gap length (i.e. in the airgap and within the magnet itself). The flux density in the airgap is given by equation (3.2), allowing the machine thrust on the electrical windings to be obtained by use of Lorenz's law, as expressed in equation (3.3) and per unit active area in (3.4).


Where tm

Br g

Mr f

V tm + Mrgy thickness of magnet (m) flux density in airgap (T) remnant flux density in magnet (T) length of airgap (m)

relative permeability (-1.05 for magnetic material) F - BgIL (3.3)

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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