As an electrical engineering apprentice working in the maintenance department of your company. Your employer is looking to introduce a wind generator mounted to the roof of the factory to reduce electricity costs. The supervisor has devised a number of activities that will evaluate the performance of a motor and a generator Task 1 Electric motors use the forces produced by magnetic fields to produce a turning motion. To understand the theory behind this, your supervisor has asked to research the characteristics of a magnetic field and produce a technical report in a professional format including the following information: a) Define magnetism. Draw a fully labelled bar magnet and the pattern of magnetic field around it (such as would be illustrated by iron filings). b) Draw a coil carrying a current. Show the direction of the current. Show the pattern of magnetic field around it (such as would be illustrated by iron filings). Identify the north and south poles. Explain the reason behind shaping a conductor into a coil. Describe the relationship between flux density (B) and field strength (H) to support your research further. You supervisor has provided with B-H curves for cast iron and 3% silicon steel, included as Appendix A. c) Explain what magnetic saturation is d) Identify saturation point for cast iron and 3% silicon steel from the curves. Compare the results e) f) Estimate the relative permeability of cast iron and 3% silicon steel at a flux of 0.3T. Compare the results Estimate the relative permeability of cast iron and 3% silicon steel at a flux of 0.7T. Compare the results. Appendix A Flux Density, B (T) 1.8 1.6 1.4 1.2 1 0.8 0.6 0.4 0.2 0 0 500 Magnetic Field Strength, H (a/m) Cast Iron, B (T) 3% Silicon Steel, B (T) 0 1000 0 500 - 12 13 0 0.12 1500 2000 1000 1500 0.25 0.38 1.48 1.52 2500 2000 0.49 1.55 B-H Properties ---Cast Iron -3% Silicon Steel 3000 3500 4000 4500 5000 5500 6000 Magnetic field strength, H (A/m) 6500 7000 7500 8000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 0.58 0.64 1.58 1.59 0.68 0.71 0.73 0.74 0.75 0.76 0.77 0.78 0.79 0.8 1.6 1.61 1.62 1.63 1.64 1.65 1.66 1.67 1.68 1.69