These motors are created for the application requirements of variable swiftness drive systems. You can expect both the following types of motors:

• Constant Torque: Motors specifically designed to handle continuous torque loads, such as for example conveyors, positive displacement pumps, cranes, etc.
• Variable Torque: Motors specifically designed to handle adjustable torque loads such as for example pumps and fans.
Due to rapid switching and reflections in the cables, motors are at the mercy of more voltage stress in the windings when fed by frequency converters than with sinusoidal supply voltage. The result of these voltages is definitely an increase of up to 2.5 times the motor’s nominal voltage. This stresses the electric motor winding insulation and can cause it to break down, resulting in possible sparking. ABB recommends:

Between 500 V and up to 600 V, the motor will need reinforced winding insulation, or the drive will need to have a du/dt filter.
Above 600 V, the motor will need reinforced winding insulation and the drive must have a du/dt filter.
If the cable size between your drive and motor is higher than 150 meters and the voltage is between 600 and 690 V, the motor will need to have reinforced winding insulation.
A variable-frequency drive is something for controlling the rotational velocity of an alternating electric current electric electric motor. It handles the frequency of the electrical power supplied to the motor. A adjustable frequency drive is usually a specific type of adjustable-acceleration drive. Variable-frequency drives are also known as adjustable-frequency drives (AFD), variable-swiftness drives (VSD), AC drives, or inverter drives.

Automatic frequency control consist of an primary electric circuit converting the alternating current into a immediate current, then converting it back into an alternating electric current with the required frequency. Internal energy reduction in the automatic frequency control is ranked ~3.5%
Variable-frequency drives are trusted on pumps and machine tool drives, compressors and in ventilations systems for huge buildings. Variable-frequency motors on fans save energy by enabling the volume of surroundings moved to match the system demand.
Reasons for employing automatic frequency control may both be related to the efficiency of the application and for saving energy. For example, automatic frequency control can be used in pump applications where in fact the flow can be Variable Drive Motor matched either to volume or pressure. The pump adjusts its revolutions to a given setpoint via a regulating loop. Adjusting the flow or pressure to the real demand reduces power intake.
An AC motor quickness control-also referred to as a adjustable frequency drive, adjustable frequency drive, variable rate drive, adjustable rate drive and AC inverter-is an electro-mechanical object that can be utilized to change the output rate of an AC engine by adjusting the insight frequency in to the motor.