Motors and Generators

Motors and Generators

Motors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?This presentation focuses on DC motors primarily because the activities for motors and generators utilize DC motors.

Project Lead The Way, Inc.Copyright 2010#Motors and GeneratorsElectromagnetsMagnet PolesParts of a Basic DC MotorElectric GeneratorsFrom the Power Plant to Your HomeMotors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?Project Lead The Way, Inc.Copyright 2010#Motors and Generators

Small DC MotorGenerator in a Hydro Plant

Geothermal GeneratorImage courtesy of DOE / NREL

Electric Turbine GeneratorMotors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?The hydro plant generator is an image from the Grand Coulee dam.

This geothermal plant is located in southeastern California.

The electric turbine is the type that might be powered by burning natural gas.Project Lead The Way, Inc.Copyright 2010#Electromagnets

NSElectromagnet ends change between north and south depending on the direction of the current.SNMotors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?Project Lead The Way, Inc.Copyright 2010#Magnet PolesNSRemember that opposite poles attract and like poles repel.If you alternate the middle magnets poles, it will continue to spin.NSNSNSThis is how motors can turn! Motors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?Project Lead The Way, Inc.Copyright 2010#Parts of a Basic DC MotorNSNS

DC SourceArmatureCommutatorBrush CommutatorBrushMotor: A device used to convert electric energy into mechanical energy.PermanentMagnetPermanentMagnetMotors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?DC Source: Provides electric current.Permanent Magnets: Also known as field magnets, these magnets provide the magnetic field for the motor.Brushes: Transfer power from the source to the slip rings.Commutator: Also known as a slip rings. Transfer the power from the DC source to the armature. The design of the slip rings are what allow the current to reverse direction. The current reversing direction causes the electromagnet to reverse polarity. This can clearly be seen in the animation.Armature: The electromagnet that spins to create rotary motion.

Project Lead The Way, Inc.Copyright 2010#

Parts of a Small DC MotorArmatureCommutatorPermanentMagnetsBrushesWireConnectionsMotors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?Project Lead The Way, Inc.Copyright 2010#Electric GeneratorsNSNS

Mechanical motion turns the armature which creates current. Many DC motors can function as a generator.

Generator: A device used to convert mechanical energy into electrical energy.

Motors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?Project Lead The Way, Inc.Copyright 2010#From the Power Plant to Your HomePower plants generate electricity.

Image courtesy of Sacramento Municipal Utility DistrictMotors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?Most electricity is produced using turbines. Turbines spin to create electricity. Usually turbines are turned using hot pressurized steam. Turbines are also often turned by wind or water pressure behind dams.Project Lead The Way, Inc.Copyright 2010#From the Power Plant to Your HomeStep up transformers increase voltage for transmission across large towers.Increased voltage increases efficiency.

Motors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?Generally the transformers at a power plant step up the voltage, whereas transformers at substations and on utility poles generally step down voltage. Power may be stepped down two to three times before it reaches buildings and homes.

The higher voltage increases efficiency because there is less heat loss.Project Lead The Way, Inc.Copyright 2010#From the Power Plant to Your HomeLarge towers transmit electricity over long distances. Images courtesy of DOE / NREL

Motors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?Project Lead The Way, Inc.Copyright 2010#From the Power Plant to Your HomeStep down transformers reduce voltage at substations to acceptable levels for the end user.

Motors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?Project Lead The Way, Inc.Copyright 2010#From the Power Plant to Your HomeElectricity arrives at your home at a junction box.Usage is measured with a meter.

Motors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?Project Lead The Way, Inc.Copyright 2010#

Step One: Wrap the Coil

1) Sand the top half of the contact on one side2) Sand all the way around the contact on the other sideContactCoilContactCut a 3ft section of Magnet wireStart coiling the wire 3 from the end of end of the wire. Wrap the wire around a 1diameter dowel rod until a 3 length remains. 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

Preparing Your Armature14Motors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?Project Lead The Way, Inc.Copyright 2010#Motors and GeneratorsElectromagnetsMagnet PolesParts of a Basic DC MotorElectric GeneratorsFrom the Power Plant to Your HomeMotors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?Project Lead The Way, Inc.Copyright 2010#Image ResourcesMicrosoft, 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.Motors and GeneratorsGateway To TechnologyUnit 6 Lesson 6.1 What is Electricity?Project Lead The Way, Inc.Copyright 2010#