For reason of energy savings, reduction of operating costs, reduction of machine down time, maximizing productivity and the ability to provide adjustable speed control with standard squirrel cage induction motors, variable speed drives are becoming the essential components in every modern automation system.
The acceleration , deceleration, high speed, low speed, foreword, reverse operation, preset speed, jogging can be programmed by the VSD, it has breaking system that uses DC injection, it’s breaking mechanism use the following principal. First is disconnect the all three phases to motor. Then its supplied 230V DC to two phases. Which operate permanent magnetic field, which hold the motor preventing motor. The speed controlling is done in VSD by changing the value V/F ( Voltage/ Frequency) in the supply to motor
Electric MOTOR in few words
An electric motor uses electrical energy to produce mechanical energy. The reverse process, that of using mechanical energy to produce electrical energy, is accomplished by a generator or dynamo. Traction motors used on locomotives often perform both tasks if the locomotive is equipped with dynamic brakes. Electric motors are found in household appliances such as fans, refrigerators, washing machines, pool pumps, floor vacuums, and fan-forced ovens. Motors operated by small batteries, while technically electric, are often called battery motors.
Most electric motors work by electromagnetism, but motors based on other electromechanical phenomena, such as electrostatic forces and the piezoelectric effect and thermal motors, also exist. The fundamental principle upon which electromagnetic motors are based is that there is a mechanical force on any current-carrying wire contained within a magnetic field. The force is described by the Lorentz force law and is perpendicular to both the wire and the magnetic field. Most magnetic motors are rotary, but linear motors also exist. In a rotary motor, the rotating part (usually on the inside) is called the rotor, and the stationary part is called the stator. The rotor rotates because the wires and magnetic field are arranged so that a torque is developed about the rotor's axis. The motor contains electromagnets that are wound on a frame. Though this frame is often called the armature, that term is often erroneously applied. Correctly, the armature is that part of the motor across which the input voltage is supplied. Depending upon the design of the machine, either the rotor or the stator can serve as the armature.
Low Voltage AC Drives
AC drives are used to control the speed and torque of a standard induction motor, the workhorse of the industry.
AC drive technology extends the motor speed range from zero to high above the rated speed, increasing the productivity of the driven process. When a low capacity is enough, the drive reduces the machine speed and saves energy. VTdrive can offer the industrial drives which are available both as complete AC drives and as modules to meet the requirements of the users, OEMs and system integrators. These drives are highly flexible AC drives that can be configured to meet the precise needs of industrial applications, and hence order-based configuration is an integral part of the offering.
Industrial drives
VTdrive can offer the industrial drives which are designed for industrial applications, and especially for applications in process industries such as the pulp & paper, metals, mining, cement, power, chemical, and oil & gas.
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