Motion Control Engineering Nidec iControl, User Manual, Page: 101 / 453

4-12 Manual # 42-02-2223
Final Adjustment
Shaping the Speed Profile
The pattern graph below charts calls out the parameters that define profile shape. The value of
pattern parameters is very important in determining the ride quality and overall elevator per-
formance. The most critical parameters are Deceleration, Flare Jerk, Approach Deceleration,
Approach Jerk and Leveling Speed. They define final stop and greatly affect floor to floor time.
Figure 4.2 Pattern Graph
Profile Parameters
• Initial jerk - transition from zero speed to full acceleration. As Initial Jerk increases, the
profile transitions more quickly from starting to maximum acceleration. Values typically
range from 4.0 to 8.0 ft/s
3
(1.219 to 2.438 m/s
3
) with higher values resulting in a sharper
start.
• Acceleration - maximum acceleration for the profile. Determines maximum current
delivered by the AC Drive during acceleration. The maximum value is typically 4.0 ft/s
2
(1.219 m/s
2
) and the minimum is usually not less than 2.5 ft/s
2
(0.762 m/s
2
). Values
higher than 4.0 ft/s
2
(1.219 m/s
2
) are possible but do not yield significant improvements
in performance.
• High roll jerk - is used on short runs where the car is not able to reach High Speed
before deceleration must begin. High Roll Jerk determines how quickly the profile transi-
tions from maximum to zero acceleration and zero to maximum deceleration. As High Roll
Jerk increases, the profile transitions more quickly. Lower values provide greater comfort
but are harder to fit into the shortest one-floor-runs. We recommend that you identify the
shortest full height floor and use it when testing parameter values. Typical values range
from a minimum of 4.0 ft/s
3
to a maximum of 8.0 ft/s
3
.
• Low roll jerk - is used on runs where the car is able to reach High Speed before decelera-
tion must begin. Low Roll Jerk determines how quickly the profile transitions from maxi-
mum to zero acceleration (High Speed) and zero to maximum deceleration. As Low Roll
Jerk increases, the profile transitions more quickly. Lower values provide greater comfort.
Typical values range from a minimum of 4.0 ft/s
3
to a maximum of 8.0 ft/s
3
.
Velocity
Time
Pattern
Initial
Jerk
Acceleration
Low Roll Jerk Low Roll Jerk
High Velocity
High Roll
Jerk
Deceleration
Deceleration
Approach
Deceleration
Approach
Deceleration
Leveling
Distance Leveling
Distance
Leveling
Velocity
Approach Jerk
Flare Jerk
Leveling
Velocity
Approach Jerk
Flare Jerk