Motors and Generators Motors and Generators • • • • • Electromagnets Magnet Poles Parts of a Basic DC Motor Electric Generators From the Power Plant to Your Home Motors and Generators Small DC Motor Image courtesy of DOE / NREL Geothermal Generator Generator in a Hydro Plant Electric Turbine Generator Electromagnets N S Electromagnet ends change between north and south depending on the direction of the current. S N Magnet Poles Remember that opposite poles attract and like poles repel. If you alternate the middle magnet’s poles, it will continue to spin. N N S S This is how motors can turn! Parts of a Basic DC Motor Motor: A device used to convert electric energy into mechanical energy. Brush DC Source Commutator N N Permanent Magnet Armature S Permanent Magnet S Commutator Brush Parts of a Small DC Motor Brushes Wire Connections Permanent Magnets Armature Commutator Electric Generators Generator: A device used to convert mechanical energy into electrical energy. Mechanical motion turns the armature which creates current. Many DC motors can function as a generator. N N S S From the Power Plant to Your Home Image courtesy of Sacramento Municipal Utility District Power plants generate electricity. From the Power Plant to Your Home Step up transformers increase voltage for transmission across large towers. Increased voltage increases efficiency. From the Power Plant to Your Home Images courtesy of DOE / NREL Large towers transmit electricity over long distances. From the Power Plant to Your Home Step down transformers reduce voltage at substations to acceptable levels for the end user. From the Power Plant to Your Home Electricity arrives at your home at a junction box. Usage is measured with a meter. Preparing Your Armature Step One: Wrap the Coil 1) Cut a 3ft section of Magnet wire 2) Start coiling the wire 3” from the end of end of the wire. Wrap the wire around a 1”diameter dowel rod until a 3” length remains. 3) Carefully hold the coil together and pull it off of the dowel rod. Wrap the coil with the 3” lengths you had left at the beginning and end of your coil. Step Two: Sand the Contacts Coil Contact 1) Sand the top half of the contact on one side Contact 2) Sand all the way around the contact on the other side Motors and Generators • • • • • Electromagnets Magnet Poles Parts of a Basic DC Motor Electric Generators From the Power Plant to Your Home Image Resources Microsoft, Inc. (2008). Clip Art. Retrieved September 10, 2008, from http://office.microsoft.com/en-us/clipart/default.aspx National Renewable Energy Laboratory (2008). Photographic information eXchange. Retrieved November 5, 2008, from http://www.nrel.gov/data/pix/searchpix.html Sacramento Municipal Utility District (SMUD). (2008). Power plant [Image]. Sacramento: Sacramento Municipal Utility District.