Four Quadrant Motor Control

Understanding how a motor works can certainly give you insight when trying to find a DC or AC motor drive for an industrial motor. One feature that’s becoming more and more popular in today’s industrial motor control industry is “four quadrant motor control.”  Machine operators want to be able to have full control and flexibility with the motor in operation without worrying about an increase in loss of material or untimely wear and tear on the motor.  With four quadrant motor control, this can easily be achieved.

Traditionally, heavy duty motors could only operate at one speed (full speed) during operation, and the rigid startup and slow down processes usually meant losing a lot of inventory for a company. The material in use would become damaged near the beginning and end of a roll or line because of inflexible motor operation.  But with new four quadrant motor control drives, both the speed and torque can be controlled.  This allows the motor to run much smoother while easing the pressure on the motor itself.

What are the Four Quadrants of a Motor?

There are four distinct areas of operation (quadrants), which are based on the directions of operation as well as the mode of operation.  The modes are the acceleration and deceleration of the motor.  Two of the quadrants represent the torque application in the direction of motion.  The other two quadrants represent the torque being applied in an opposite direction from the motor’s motion.

So the motor has two quadrants in which the energy flow is from an electrical flow to a mechanical flow.  With the other two, however, the motor acts as a generator. As the motor is in motion, this motion is being converted into electrical power.  The motor drive absorbs this power.

DC Drives for Four Quadrant Motor Control

While many motor drives can only operate in one or two quadrants, some offer four quadrant motor control.  This means the drive provides accurate control in both directions by sourcing and sinking the motor’s electrical power.

Our Elite Series DC drives are a great example of a drive featuring four quadrant motor control.  These offer full range speed and torque control for motors with a horsepower rating range of 5 to 300 HP.  They can control motors that are rated for NEMA type C or D power supplies, and there are models available that provide 12 SCR regenerative control.  Options such as contactor run/brake chassis models, disconnect switches, blower starters, braking resistors, and more are available so you can easily find the one needed for your industrial application.

With four quadrant motor control drives, your machinery and DC motors can run better than ever…saving you on production costs and reducing long-term profit losses.

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