User Manual Instruction Manual

13-12 GV6000 AC Drive User Manual
13.5 Motor Control Technology
Within the GV6000 there are several motor control technologies:
• Torque Producers
• Torque Controllers
• Speed Regulators
Torque Producers
Volts/Her tz
This technology follows a specific pattern of voltage and frequency output to the
motor, regardless of the motor being used. The shape of the V/Hz curve can be
controlled a limited amount, but once the shape is determined, the drive output is fixed
to those values. Given the fixed values, each motor will react based on its own
speed/torque characteristics.
This technology is good for basic centrifugal fan/pump operation and for most
multi-motor applications. Torque production is generally good.
Sensorless Vector
This technology combines the basic Volts/Hertz concept with known motor parameters
such as Rated FLA, HP, Voltage, stator resistance and flux producing current.
Knowledge of the individual motor attached to the drive allows the drive to adjust the
output pattern to the motor and load conditions. By identifying motor parameters, the
drive can maximize the torque produced in the motor and extend the speed range at
which that torque can be produced.
This technology is excellent for applications that require a wider speed range and
applications that need maximum possible torque for breakaway, acceleration or
overload. Centrifuges, extruders, conveyors and others are candidates.
Torque Controllers
Vector
This technology differs from the two above, because it actually controls or regulates
torque. Rather than allowing the motor and load to actually determine the amount of
torque produced, Vector technology allows the drive to regulate the torque to a defined
value. By independently identifying and controlling both flux and torque currents in the
motor, true control of torque is achieved. High bandwidth current regulators remain
active with or without encoder feedback to produce outstanding results.
This technology is excellent for those applications where torque control, rather than
mere torque production, is key to the success of the process. These include web
handling, demanding extruders and lifting applications such as hoists or material
handling.
Vector Control can operate in one of two configurations:
1. Encoderless