Dec 21, 2015
Hydraulic Hybrid VehicleMembers:
Kevin Alexander
Phillip Bacon
Tyler Degen
Brandon Diegel
Nick Hemenway
Luke Jackson
Christian L’Orange
Grant Mattive
Dean Simpson
Advisors:
Dr. Kirkpatrick, CSU
Dr. Guy Babbitt, Czero Inc.
Mr. Chris Turner, Czero Inc.
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 fuelsavings and reduced maintenance cost• Major components sourced from commercialmanufacturers
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
D
CAMEK
RPMD
N7425
Where:N-Max safe speedC-.9 for variable speedA-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 diameterD- Outside diameter in feetTaken from Machinery’s Handbook
N=
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
1800rpm Centrifugal load3500rpm Centrifugal load
Max Stress: 3.30ksi Max Stress: 13.65ksi
Accumulator Selection
10 Gallon 15 Gallon
•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 Selection
Accumulator considerations
• Size of P/M dependant on acceleration path
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
Pump/Motor Selection
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
Test Skid Schematic
M
CV1
Flywheel
PRV1
Control Valve
PRV2
PRV3
Manual Valve
Hydraulically Actuated Valve
Hydraulic Power Source
Control
LP HP
P/M
Brake