Transcript Hydraulic Hybrid - College of Engineering

Hydraulic Hybrid Vehicle
Members:
Advisors:
Kevin Alexander
Dr. Kirkpatrick, CSU
Phillip Bacon
Dr. Guy Babbitt, Czero Inc.
Tyler Degen
Mr. Chris Turner, Czero Inc.
Brandon Diegel
Nick Hemenway
Luke Jackson
Christian L’Orange
Grant Mattive
Dean Simpson
Outline
• Objectives and Constraints
– Scope Changes
• Test Skid Progress
• Component Selection
– Accumulator
– Pump/Motor
•
•
•
•
Modeling Progress
Current Schedule
Budget
Conclusions
Background/Review
Objectives and Constraints
• Design components to retrofit existing vehicles
• Operational Test Skid by Dec. 2007
• Running prototype vehicle by April 2008
• Payback period: less than 2 years through fuel
savings and reduced maintenance cost
• Major components sourced from commercial
manufacturers
Scope Changes
• Test Skid
– Test skid from University of Wisconsin, Madison
– Initial set-up: Stock configuration at 2000psi
– Final set-up: Sized components at 5000psi
• Marketing
– Partnered with CSU College of Business GSSE
• Controls
– Partnered with CSU team of electrical engineers
Test Skid Progress
• Acquired test skid from University of Wisconsin
• Installed at the EECL
• Flywheel-to-pump coupler ordered
• Flywheel FEA conducted
• EECL donated hydraulic power supply
• Installed HPS near test skid
• Evaluated condition of components
• HPS is currently operational
Flywheel Selection
• Sizing flywheel to simulate reflected inertia of bus
• Options considered:
Clark flywheel at EECL (5 ft diameter)
Trainwheel (3 ft diameter)
University of Wisconsin Flywheel (2 ft diameter)
In house fabricated flywheel
• Main concern is safety
Flywheel Selection
N=
CAMEK
D
Where:
N-Max safe speed
C-.9 for variable speed
A-1.5 for disk type (no spokes)
M-2.75 for plate/forged steel (60ksi)
E-1.0 for solid rim (no bolted joints)
K- ~2000 for thickness of 5% outside
diameter
D- Outside diameter in feet
Taken from Machinery’s Handbook
7425
N
RPM
D
Flywheel
Max Safe
Speed
(rpm)
Max
Modeling
Capability
(mph)
Clark
315
30
UW
3500
20
UW (rings)
3500
37
Trainwheel
2500
39
Flywheel Selection
• New Constraint: If building own test stand, moment
of inertia must be under 4 kg-m2 for safety purposes
• Decided to use UW test stand since it was
professionally designed and best utilization of tight
time frame
• Will still allow for sufficient modeling capabilities
when inertia rings are designed and added
Flywheel Analysis
•Flywheel modeled at 1800rpm and 3500rpm
•Centrifugal loading applied to model
Max Stress: 3.30ksi
1800rpm Centrifugal load
Max Stress: 13.65ksi
3500rpm Centrifugal load
Accumulator Selection
10 Gallon
15 Gallon
Accumulator Selection
•15 gallon capacity
•Suitable for testing equipment
•Bladder type accumulator
Bladder material Hydrin (desirable temperature and cost properties)
•Steel construction
Best performance to cost ratio
•Top repairable
Desirable for ease of maintenance
Accumulator considerations
Pump/Motor Selection
• Size of P/M dependant on acceleration path
Acceleration
2.5
2
10
m/s
1.5
1
5
0.5
0
0
0
10
0
20
5
10
15
time (s)
time (s)
Displacement
250
200
cm^3/rev
m/s^2
Velocity
15
150
100
50
0
0
5
10
15
time (s)
20
25
20
25
Pump/Motor Selection
• Variable Displacement Axial Piston Pump/Motor
• Through Shaft Swash Plate type
• No extra coupling gearbox to mount to vehicle
• Bosch Rexroth A11VL0
– Displacement- 145 cm^3/rev
– Maximum Pressure of 400 Bar
– Max Speed of 2500 rpm
– 73 kg
Modeling Progress
• Simulink models
– Drive cycle: fuel economy, accelerating and
braking capabilities
– Hydraulic model: component sizing, pressure
considerations
• Hysan models
– Hydraulic schematic: pressure considerations, line
losses, and modes of failure
Current Schedule
Issues List
Budget
• Components needed for test skid
Low and High Pressure Accumulator ~$6000
Final set-up pump/motor ~$7000
•Donations
Talked to City of Fort Collins for a donated vehicle
In talks with hydraulic suppliers for possible donations
Questions
Special Thanks To:
Dr. Kirkpatrick (Advisor-Colorado State
University)
Dr Guy Babbitt (Advisor-Czero Inc.)
Chris Turner (Advisor-Czero Inc.)
Staff and Employees of The Engines
and Energy Conversion Laboratory
Hysan Modeling
PRV3
Test Skid Schematic
LP
Flywheel
HP
Brake
P/M
Control
Valve
Control
PRV1
Hydraulically
Actuated Valve
CV1
Manual
Valve
Hydraulic Power
Source
M
PRV2