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Is a VFD or Valve Faster?

What are the factors that affect VFD rangeability?

Many applications use one or more motors operating in parallel at the same desired speed. Using one Variable frequency drive (VFD) to control these multiple motors provides a host of advantages

The term "multi-axis synchronization" refers to the motion which requires coordination, and the techniques used to achieve control of the motion. With today's increasing automation and machine sophistication, the control applications have become more demanding, and the control techniques have improved.

Optimum motor control packages start with a drive to provide the most control, flexibility, and protection. Adding a bypass with an integral soft starter provides a backup system to run the motor should the drive fail. Large drive systems should have soft starters in the bypass, otherwise the application risks negatively affecting the power system, damaged bearings, or bent shafts once the bypass is engaged.

Adjustable Speed Drives are used in any application in which there is mechanical equipment powered by motors; the drives provide extremely precise electrical motor control, so that motor speeds can be ramped up and down, and maintained, at speeds required; doing so utilizes only the energy required, rather than having a motor run at constant (fixed) speed and utilizing an excess of energy.

Users are pushing motors closer to their theoretical torque and power limits. In order to protect motors under these rated conditions, accurate thermal models of the motor are needed.

A Variable Frequency Drive regulates the speed of a 3-phase AC electric motor by controlling the frequency and voltage of the power it delivers to the motor. Today, these devices are becoming prevalent in a wide range of applications throughout the industry, from motion control applications to ventilation systems and many others.

The fundamental concepts of servo motion control have not changed significantly in the last 50 years. The basic reasons for using servo systems in contrast to open loop systems include the need to improve transient response times, reduce the steady state errors and reduce the sensitivity to load parameters.