ABB MicroFlex e190, Руководство пользователя

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Resistor braking 173
Braking energy calculation
The following calculations can be used to estimate the type of brake resistor that will
be required for the application. To complete the calculation, some basic information is
required. Remember to use the worst-case values to ensure that the braking power is
not underestimated. For example, use the maximum possible motor speed, maximum
inertia, minimum deceleration time and minimum cycle time that the application might
encounter.
Requirement Enter value here
a) Initial motor speed, before deceleration
begins, in radians per second.


Multiply RPM by 0.1047 to give radians
per second.
Initial motor speed, U = _________ rad/s
b) Final motor speed after deceleration is
complete, in radians per second.


Multiply RPM by 0.1047 to get radians
per second. This value will be zero if the
load is going to be stopped.
Final motor speed, V = _________ rad/s
c) The deceleration time from initial speed
to final speed, in seconds.
Decel time, D = _________ s
d) The total cycle time (i.e. how frequently
the process is repeated), in seconds.
Cycle time, C = _________ s
e) Total inertia.


This is the total inertia seen by the drive,
accounting for motor inertia, load inertia
and gearing. Use the Mint WorkBench
Autotune tool to tune the motor, with the
load attached, to determine the value.
This will be displayed in kg·m
2
in the
Autotune tool. If you already know the
motor inertia (from the motor spec.) and
the load inertia (by calculation) insert the
total here.


Multiply kg·cm
2
by 0.0001 to give kg·m
2
.
Multiply lb-ft
2
by 0.04214 to give kg·m
2
.

Multiply lb-in-s
2
by 0.113 to give kg·m
2
.
Total inertia, J = ________ kg·m
2