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From Motors and Drives

Introduction
Basically, four different types of DC motors are used in industrial applications: series wound, shunt wound, compound wound, and permanent magnet. Several factors must be considered when selecting a DC motor for a specific application.

First, decide what the allowable variation in speed and torque can be for a given change in load. Each type of motor has benefits that are advantageous for certain applications. The following review will help you decide which motor may provide better performance in a given application. The DC motor and drive specifications should always be consulted to determine the specific speed and torque capabilities of the system. The speed/ torque curves listed below are for illustrative purposes.

Series Wound DC Motors
A series wound DC motor has the armature and field windings connected in a series circuit. Figure 3-17 shows a series wound DC motor, with an associated speed/torque curve.

As seen in Figure 3-17, this type of motor configuration features very high breakaway torque. Typical applications for this motor would be printing presses, ski lifts, electric locomotives, cranes, and oil drilling.

The starting torque developed can be as high as 500% of the full load rating. The high starting torque is a...


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Products & Services
Brushless Motors
Brushless motors are synchronous electric motors that have a magnetically (AC induction) or electronically (DC) controlled commutation system instead of a brush-based mechanical commutation system.
Electrical Winding Services
Companies that specialize in the fabrication of custom wound assemblies for a wide range of electrical applications and industries. Electrical winding services also includes the repair and refurbishing of individual wound components.
DC Motors
DC motors are most commonly used in variable speed and torque applications. They include brushless and gear motors, as well as servomotors.
Stepper Motors (rotary)
Stepper motors use a magnetic field to move a rotor in small angular steps or fractions of steps. They provide precise positioning and ease of use, especially in low acceleration or static load applications.
DC Servomotors
DC servomotors are generally small and powerful for their size, and easy to control. Common types of DC servomotors include brushless or gear motors.

Topics of Interest

Introduction The squirrel cage induction motor is probably the most widely used motor in industry today. Traditional applications for AC induction motors include fans and pumps. The AC induction motor...

AC and DC motors are the two major types in use today that are related to the industrial and HVAC applications. These motors provide the speed, torque, and horsepower necessary to operate the...

Basic Components Two basic circuits are in any DC motor: the armature (the device that rotates, sometimes referred to as a rotor) and the field (the stationary part, sometimes referred to as a stator...

What are the two main parts of a DC motor and what is the purpose of each? What is the purpose of the brushes? Why are the laminations in the armature skewed? What is the purpose of the...

Discussions of and problems related to series-wound dc motors, shunt-wound dc motors, series-shunt-wound dc motors, shunt motor torque, induction motor speed, induction motor efficiency, induction...