by Patrick Opdenbosch

1
EHPV Technology
Advanced Control Techniques for Bi-directional
Proportional Flow Control Valve
by Patrick Opdenbosch

• Project Goals
• Develop advanced and robust techniques for flow
  control of EHPV.
• Experiment with highly non-linear systems.
• MS/Ph.D. degrees

• Research Guideline
• Examination of related works.
• Development of EHPV mathematical model.
• Identification of EHPV parameters.
• Validation of mathematical model.
• Development of control techniques
• Jacobian linearization.
• Input-output linearization.
• Optimal control.
• Other more advanced techniques.
• Run simulation on Hardware-in-the-loop.

• Valve Features
• Zero leak
• Precise metering control
• Variable electronic control

Solenoid
Abstract The current trend in construction
machinery is to use electrically controlled
valves (solenoid valves) instead of manually
operated hydraulic valves. One of the benefits is
that these solenoid valves need not be located in
the operator cab. In addition, the employment of
these electrically driven valves facilitates
computerized control of various machine
functions. The Electro-Hydraulic Poppet Valves
(EHPV), a kind of solenoid valves, are used
herein for flow control in hydraulic machinery.
The flow control through the valve is achieved by
changing the valve restriction coefficient via a
poppet type orifice with pressure compensation.
The integrated electronics makes practical
advanced control algorithms to further extend the
valve capabilities in new ways and its
application. This project will explore new
algorithms and applications via theory,
simulation and operation of the valve in Hardware
In the Loop (HIL) simulation facility currently
under construction
Input current
Pilot poppet
3
6c
4
1 Reservoir Tank 2 Pump 3 EHPV supply 4
Check valve 5 EHPV return 6 Actuator 6a
Lower cavity 6b Upper cavity 6c Piston
Supply Return
6b
Control pressure
5
6a
Patented pressure compensation method
6
4
2
3
5
1
1
INLET FLOW
Wheatstone Arrangement to Control Actuator
Displacement
Main poppet
OUTLET FLOW
duv
dxp
dPp
dxm
Mathematical Model for a Single EHPV from
Equilibrium State
dQa
dQb
Simulation of Valve Response About Equilibrium
Flow for a PWM Input Current
Sponsors HUSCO International and FPMC Center
EHPV States, Flows, and Input from Equilibrium

• Advisors
• Dr. Nader Sadegh, Dr. Wayne Book

website http//www.imdl.gatech.edu/opdenbosch
Spring 2003
Email gte608g_at_prism.gatech.edu