- General Electric Computer Accessories User Manual

GEH-6385 Reference and Troubleshooting, 2300 V Drives Chapter 3 Paramters/Functions •
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• 3-111
Ovrd/Spd forced Forced Torque, spd override mode:
Speed regulation mode dynamically forced because
either the value of the signal specified by Torque mode
sel is False, or the Torque reg stop mode is
commanded by the sequencer.
Ovrd/Spd Low Active Torque, spd override mode:
Speed regulation mode dynamically overrides torque
mode due to Speed reg error having exceeded limit
specified by Spd reg pos err lim.
Ovrd/Spd High Active Torque, spd override mode:
Speed regulation mode dynamically overrides torque
mode due to Speed reg error having exceeded limit
specified by Spd reg neg err lim.
Lcl mode/Spd reg Active Local speed mode:
Drive is operating in Speed regulation mode in response
to DDI commands. This mode is forced by local
operation regardless of the configuration specified by
the parameter Regulator type. The Torque ref input
signal is disabled.
The speed regulator compensation network is fairly classical. It has parameters to
adjust the proportional gain of command, proportional gain of feedback, and integral
gain of speed error. Proportional and integral contributions are summed, and a final
gain stage applies inertia compensation cascaded with a net gain term. A unity-gain
lowpass filter is provided to allow softening of the proportional paths.
Anti-windup is provided to the integrator in the form of a pair of Booleans, Torque
ctl pos frz and Torque ctl neg frz, provided from the motor control interface.
Assertion of an anti-windup Boolean inhibits integrator changes in the associated
positive or negative direction; the Boolean Speed reg antiwindup provides indication
of the active status of this dynamic integrator limit.
Inertia compensation is defined by the parameter Fixed inertia unless the parameter
Variable inertia sel is used. Actual platform signal units for specified Inertia are (kg-
m^2), although the product human interfaces (Tool & DDI) allow treatment in (lb-
ft^2) if preferred. Units represent the transformation between torque and acceleration
expressed in terms of a mass and a radius of gyration. Data expressed as Wk^2 can
be entered directly; data expressed in GD^2 should be divided by four prior to entry
(to reflect the ratio between radius-squared and diameter-squared).
Related diagrams
• Speed Regulator (SReg)