![Page 1: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/1.jpg)
UNH ECE 791
Senior Project I
Design Proposal Presentation
![Page 2: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/2.jpg)
Team
Members:• Luke Vartuli
• Stephen Doran
• Doug MacMillan
Advisor:• Dr. Gordon Kraft
![Page 3: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/3.jpg)
Problem Statement
Problem:• Noise• Emissions• Cost of operation
Solution:• Electric snowmobile
![Page 4: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/4.jpg)
Project Overview
• Starting point => Polaris Snowmobile
• Breakdown of snowmobile
• Electric motor– Motor Theory
• Motor Control
• Pulse Width Modulation
• PWM circuit
• Power MOSFET’s
• Mounting bezels
• Battery type
• Battery mounting
• Timeline
• Budget
• Contributions
![Page 5: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/5.jpg)
Starting Point
Donor Sled: 1996 Polaris Indy XLT
![Page 6: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/6.jpg)
Breakdown of Snowmobile
Components Removed:• Engine• Exhaust• Fuel tank• Oil tank• Starting battery• Cooling system
![Page 7: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/7.jpg)
Electric Motor
Specifications:• Mfg: General Electric• Model: 2CM6501Nameplate Ratings:• Voltage: 120VDC
• Armature Current: 167 A• Field Current: 10 APlace of Origin:• WWII Era B-29 Aircraft
![Page 8: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/8.jpg)
Armature
• Main component of the DCMG
• Uses multiple Armature windings for conduction
• Undergoes Dynamo effect
![Page 9: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/9.jpg)
Shunt DCMG
• Armature and Inter-poles are in parallel to the Main poles.
• As load changes only a fraction of the field will change.
• Safer, but has bad torque characteristics
![Page 10: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/10.jpg)
Shunt Diagram
Armature
+
-
NS
Interpoles
LOAD
![Page 11: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/11.jpg)
Windings
1 2 3 4 5 6 7 8 9 10 11 12 13 14
SIMPLEX WAVE WINDING
1516
Since the coils span every 3 commutator segments. This is
considered a simplex wave winding with a triplex commutator pitch.
The Commutator pitch is as follows….
Yc = (C ± m)/(P/2)WhereYc = Pitch of commutator
C = number of commutator segments
m = the plex of winding, or in context. The span of the coil from one segment to another. For instance since above winding is a triplex. m= 3
P= number of poles
The coil pitch for this unit is as follows….
Ys = S/P WhereYs = Coil pitchS = number of armature slotsP = number of poles
It is important that no matter the number you get you must round down to the next integer. If its 12.6 then Ys = 12. If its 10 then Ys = 10.
Single Element coil
Simplex Lap
![Page 12: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/12.jpg)
Commutator
• “Assembly line for current transfer”
• As the commutator spins, current conducts from the brush (-) to the commutator bars the Load back to the Brush’s(+).
![Page 13: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/13.jpg)
Inter-poles
• Maintains a neutral field flux over the commutator as the load changes.
• By having a neutral field flux over the commutator, this limits “sparking” on the commutator which then leads to pitting and damage. This will disrupt proper commutation.
![Page 14: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/14.jpg)
Inter-poles at work!
Y-Axis
S NN
Full Load Magnetic field
No Load Magnetic field
S N
Full Load Magnetic field
No Load Magnetic field
Y-Axis
Time
Neutral- No Load and Full Load
No Load Neutral Full Load Neutral
No Inter-poles
With Inter-poles
![Page 15: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/15.jpg)
Motor Control
How the motor will be controlled:• Vary armature current, fixed field• Pulse Width Modulation (PWM)• Power MOSFET’s
![Page 16: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/16.jpg)
Pulse Width Modulation (PWM)
• Use PWM to control armature, fixed field• PWM controls power MOSFET’s• As duty-cycle increases, switches on longer,
motor spins faster
![Page 17: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/17.jpg)
PWM circuit
![Page 18: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/18.jpg)
Power MOSFET’s
Pros:• High current• Fast switching• Low resistance
Cons:• No protection from fly
back voltage• Get hot
![Page 19: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/19.jpg)
Mounting Bezels
Key Components:• Bed plate• Motor• Motor bezel• Bearing Bezel• Clutch assembly• Orig. Motor Mounts
![Page 20: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/20.jpg)
Battery Type
Flooded Lead Acid, Why?• Availability• Low cost• Ease of configuration• Ease of mounting• Ease of connection
Source: www.carbasics.co.uk/inside_car_battery.gif
![Page 21: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/21.jpg)
Battery Mounting
Configuration: Series
Nom. Voltage: 120VDC
Mounting: Battery rack with top straps
![Page 22: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/22.jpg)
Timeline
![Page 23: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/23.jpg)
Budget
• Snowmobile: Donated
• Electric Motor: Donated
• Wire and misc. supplies: Donated
• Mounting Bezel: $200
• Batteries: $1000
• Pulse Width Modulator: $150
![Page 24: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/24.jpg)
Contributions
Donations:• Snowmobile donated by Vincent Pelliccia• DC Motor donated by Kevin White• Wire and misc. electrical materials donated by Vartuli Electric, LLC
Support and Guidance:• Prof. Kraft• Prof. Hludik• Prof. Clark• Prof. Smith• Adam Perkins• Matt Borowski
![Page 25: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/25.jpg)
Thank you for your time
![Page 26: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/26.jpg)
DC MOTOR THEORY
• Same concept as AC Motor/Generators
• Utilizes carbon brushes for DC characteristics
![Page 27: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/27.jpg)
Flemings right Hand rule
S
N
Conductor Movement
Field Flux
Current
+
_
![Page 28: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/28.jpg)
Armature Physics
S
N
As the conductor changes direction, the current and voltage will also change
polarity
Armature Flux from Current
Simple Voltage production using a conductor and two magnets of
opposite polarity
Load
![Page 29: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/29.jpg)
Commutation Diagram50 A50 A050 A50 A50 A
50 A 50 A
Rotation
+ Brush
100 Amps
Current from negative polarity
brush
Current from negative polarity
brush
Coi
l Cur
rent
Distance0
+50
-50
Armature Coils undergoing Ideal Commutation
Rotation
- Brush
Current going to positive polarity
brush
Current Going to positive polarity
brush
50 A50 A050 A50 A50 A
![Page 30: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/30.jpg)
N S
Magnetic Field between two
magnets
SN +
Armature induced EMAG
Rotation
N SRotation
New Magnetic field due to combination
++
+
++
+
90
Neutral
F
Vector F repersents
MMF due to Main poles
Fa F0
F
New Neutral
Fa
Vector Fa represents
MMF due to armature
induced current
Due to the field MMF vector F and the armature MMF vector Fa combine at right angles to form the resultant field MMF vector
F0
Armature current
![Page 31: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/31.jpg)
Compound DCMG
• Utilizes both series and shunt characteristics
• More common DCMG
![Page 32: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/32.jpg)
Compund Diagram
ArmatureN S
InterpolesShunt Connection
Series Connection
LOAD
![Page 33: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/33.jpg)
Series DCMG
• Poles, Inter-poles, and Armature all in series.
• Change in load is directly proportional to change in speed.
• Reduction in load can cause a “run-away” motor which will then lead to mechanical failure.
• High torque applications.
![Page 34: UNH ECE 791 Senior Project I Design Proposal Presentation](https://reader035.vdocuments.us/reader035/viewer/2022062718/56649e685503460f94b6423b/html5/thumbnails/34.jpg)
Series DCMG diagram
ArmatureNS
Interpoles
LOAD