Select The Control Principle; Acquire The Signals; Create The Set Point - Danfoss pved-cl Operation Manual

Operation Manual
PVED-CL Controller for Electro-Hydraulic Steering, Version 1.38
Steering by Low Priority Steering Device – Closed Loop

Select the Control Principle

Create the Set Point

90 | © Danfoss | May 2016
set point and current steering actuator position or by sweeping through it. While tracking, the
commanded port flow is limited at zero.
Yr, Yl, Lx, Xysat, db
Xstl -
10 ms
Pot-
Angle
meter
like
Setpoint
device
Yact -
Actuator
position
Cp selects the closed loop control using parameter index 4y02 equal to 255. Y selects the program and
ranges from 0 and 4. The value for y must be consistently used throughout the entire configuration of a
single program.

Acquire the signals

See Mapping a Steering Device
loop steering device and steering wheel angle sensor.
A function provides 5 parameters to transform angle information to a steering actuator position set point.
Right steering
actuator end-lock
Example:
db = 250, Lx = 10
Xysat = 750
YR = -750
YL = 500
YL
Max input signal
for activating the
steering device
into the left
-1000 -750 -500
direction
Defaults:
db = 0, Lx = 0
Xysat = 1000
YR = 1000
YL = -1000
saturation
db Sets a dead band about the middle region of the signal. The parameters prevent self-steering, caused
by manufacturing deviations in the signal when the handle is in the middle or released position.
However, db is normally set to zero for pot-meter like steering devices.
The default value is set to serve pot-meter like steering devices
Lx Set the curve linearity. The parameter is set down when the cylinder position is too far (over-steer) for
small steering angles or vice versa. The optimum value for this parameter is closely related to:
•
The inherent linearity between steering actuator position and signal
•
The inherent linearity between device handle angle and signal
•
The inherent over or under-steer tendency of the vehicle when steering into curves
•
The default value will not effect the resulting relation.
YR, YL The difference between the values of both parameter set the freedom of the steering actuator.
Normally, YR is set equal at the right mechanical end lock. YL is normally set equal to the left mechanical
Qm
Port flow
Kp Tracking
limiter
10 ms
on page 31 on how to map an analogue or CAN-based high priority closed-
1000
Xysat
750
500
Lx
250 db
250
-250 500 750
Xstl - Input signal: 1
-250
unit = 0.1% of max
activation
-500
-750
Left steering
-1000
actuator end- lock
Q - Port flow
command
P005 211E
YR Max input signal
for activating the
steering idevice
into the right
direction
1000
P005 212E
11025583 | AQ00000216en-US0302