Armature Excitation

Replacing the magnetic regions of the simulation with air allows the inductances of the phases to be investigated. The single three phase coil inductance results for the simulation are presented Figure 5.15 and confirm the 50 mm cyclic nature.

Further confirmed in this diagram are the existence of three out of phase levels of inductance, namely the self inductance, mutual inductance of adjacent coils and the mutual inductance of non-adjacent coils. In this model, calculation of one of each of these values in combination with the known phase difference may be used to describe all three coils.

Figure 5.15: Single coil inductances

The validity of the inductance estimate of Section 5.1.7.3 may now be tested. The distributed mmf model gave a predicted value of 8.2 mH, whereas the results here show that the actual inductance varies between 12 and 13.5 mH . The error of the highly simplified method is of the order of 30-40% inaccurate.

The flux linkage map of Figure 5.16 demonstrates the effect of coil position and current on flux linkage for a single phase. The graph shows a sinusoidal variation with position in combination with a linear relationship for current which is symmetrical about the origin. The linear relationship and symmetry about the zero current axis shows the inductance is independent of current.

poistion (mm)

Figure 5.16: Flux linkage map of single coil (B)

poistion (mm)

Figure 5.16: Flux linkage map of single coil (B)

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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