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Chapter 3 Paramters/Functions Innovation Series Medium Voltage GP Type - G Drives GEH-6385
Motor Control Functions

Motor Control Overview

The Innovation Induction motor control algorithm utilizes a Flux-Vector control
strategy. The motor control featur es include the following:
• Motor torque, flux and thermal models
• Online motor parameter s adaptation
• Voltage and current regulators
• Voltage feedback offset c orrection
• Power-Dip ride through control
• Tach and Tachless mode operation
• Tach loss detection
• Current limit and Motor pull-out limit
• Automatic field-weaken ing control
• Torque Compensation
• Cross-over voltage control
Motor Equivalent Circuit parameter information is required for the motor controller.
These parameters can be obt ained by running the Motor Control Tuneup wizard
during commissioning of the drive. The motor parameters will change due to motor
temperature variations; because of this, on-line parameter adaptation, motor thermal
model and torque compensation schemes (shown in diagram, Motor Control
(Ovr_MCtrl) are incor porated in the motor control to ena ble accurate tracking of
torque, flux and calcula ted speed.
Motor electrical model s are used to form feedforward model s, feedback torque, flux
and speed calculati ons.
The induction motor controller can be used with or without tachometer. It can also be
configured to operate in tachometer control mode with automatic switch over to
Tachless control upon detection of a Tach-loss situation (comparison between model
calculated speed an d actual speed feedback signal).
Field flux control can be manipulated by Flux ref ratio (inputs to motor control
shown in the diagram, Motor Control (Ovr_MCtrl). However, if the inverter output
voltage approaches its limit (Crossove r Voltage) by increasin g speed, an automatic
field-weakening control will take action to limit the output voltage (by reducing flux
command) to the Crossover Voltage level.
Current limits in the drive are affected by motor Pull-out torque capability, Power
Dip Protection control, and user current limit setting (as shown in diagram Motor
Control Interface (Core)). Motor pullout limit normally occurs when a large torque is
demanded in deep field- weakening operating region.
Related diagrams
• Motor Control Interface (Core)
• Motor Control (Ovr_MCtrl)