These motors are designed for the application requirements of variable speed drive systems. You can expect both the following types of motors:
• Constant Torque: Motors specifically designed to handle constant torque loads, such as conveyors, positive displacement pumps, cranes, etc.
• Variable Torque: Motors specifically designed to handle variable torque loads such as 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 as high as 2.5 times the motor’s nominal voltage. This stresses the 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 needs to have reinforced winding insulation, or the drive must have a du/dt filter.
Above 600 V, the motor will need reinforced winding insulation and the drive must possess a du/dt filter.
If the cable size between your drive and engine is higher than 150 meters and the voltage is between 600 and 690 V, the electric motor will need to have reinforced winding insulation.
A variable-frequency drive is something for controlling the rotational rate of an alternating electric current electric engine. It settings the frequency of the electrical power supplied to the electric motor. A adjustable frequency drive is a specific type of adjustable-swiftness drive. Variable-frequency drives are also called adjustable-frequency drives (AFD), variable-quickness drives (VSD), AC drives, or inverter drives.
Variable Drive Motor automatic frequency control contain an primary electrical circuit converting the alternating current into a direct current, after that converting it back into an alternating current with the mandatory frequency. Internal energy reduction in the automated frequency control is ranked ~3.5%
Variable-frequency drives are trusted on pumps and machine tool drives, compressors and in ventilations systems for large buildings. Variable-frequency motors on supporters save energy by permitting the volume of atmosphere moved to complement the system demand.
Reasons for employing automatic frequency control may both be linked to the functionality of the application and for conserving energy. For example, automatic frequency control is used in pump applications where in fact the flow is matched either to volume or pressure. The pump adjusts its revolutions to confirmed setpoint via a regulating loop. Adjusting the movement or pressure to the actual demand reduces power usage.
An AC motor quickness control-also known as a adjustable frequency drive, adjustable frequency drive, variable acceleration drive, adjustable quickness drive and AC inverter-is an electro-mechanical object that can be utilized to change the output swiftness of an AC motor by adjusting the input frequency in to the motor.