Speed Matching (Internal Overload Protection) - ABB ACS800 Firmware Manual

Speed matching (internal overload protection)

The Speed matching function is an internal overload protection function. It
supervises the motor torque. The function checks that the motor follows the speed
reference during acceleration and deceleration, and does not have an excessive
speed error during acceleration, deceleration and when running at the constant
speed.
There are two different parameters that can be used to define the speed matching
deviation, one during acceleration/deceleration and the other during steady state.
Parameter
running in the steady state or when the motor is not accelerating or decelerating.
This is defined in terms of percentage of Par.
Parameter
second in terms of percentage of Par.
the difference between the rate of change of the motor speed and the rate of change
of the ramped speed reference is within this value during acceleration or
deceleration. If the difference between the rate of change of the motor speed and the
rate of change of the ramped speed reference is greater than the setting of Par.
75.04
FLT.
Example: Acceleration/deceleration ramp times are set to, for example, 3 seconds.
The maximum speed is 1500 rpm. Therefore, the drive speed reference should ramp
at 500 rpm/s or 33%/s. With SPD CHG PER SEC set to 2% / s (30 rpm/s), the drive
does not trip on SPD MATCH FLT during acceleration/deceleration as long as the
rate of change of the motor speed is within (31% to 35%). In the steady state, if the
SPD DEV LEV is set to 10%, the drive will trip when the difference between the
major speed and the ramped speed reference is greater than 150 rpm (10% of 1500
is 150 rpm). See the following figure. If the speed deviation is outside the window as
shown in the figure, the drive will wait for the Par.
and then trip on the SPD MATCH FLT fault.
(rpm) (rpm)
1500rpm 1500rpm 1500rpm
1000rpm 1000rpm 1000rpm
500rpm 500rpm 500rpm
The speed change must be within 31% (= 470 rpm/s) and 35% (= 530 rpm/s).
75.02 SPD DEV LEV is used to check the deviation when the motor is
75.04 SPD CHG PER SEC, the rate of the actual speed change in % per
for a period of Par. 75.03
500rpm 500rpm 500rpm
1s 1s 1s
20.02
20.02 MAXIMUM SPEED, can be set so that
SPD MATCH FLT TD, the drive trips on SPD MATCH
75.03
500rpm 500rpm 500rpm
500rpm 500rpm 500rpm
2s 2s 2s 3s 3s 3s
MAXIMUM SPEED.
SPD MATCH FLT TD period
1650rpm 1650rpm 1650rpm
1350rpm 1350rpm 1350rpm
Program features
87
(s) (s)