Torque is proportional to flux and armature current; speed is controlled by voltage.
Armature voltage V=E+I_aR_a with E=kΦω. Torque T=kΦI_a. Speed is controlled by armature voltage or field flux. Excellent torque control and starting, but brushes need maintenance.
A 240 V motor with R_a=0.5 Ω at 20 A runs on E=230 V.
DC motors give simple speed and torque control, which is why they are used in tools, robots and traction systems.
Torque is proportional to flux and armature current; speed is controlled by voltage.
DC motors give simple speed and torque control, which is why they are used in tools, robots and traction systems.
Torque is proportional to flux and armature current, so increasing the current increases the torque.
Changing the armature voltage changes the back EMF balance, which sets the speed, and field weakening can raise speed further.
Typical applications include controlling the speed of a small DC motor with a PWM driver, calculating the torque needed for a winch with a DC motor and setting the voltage on a motor for a constant speed in a conveyor.
Study "DC generators" first (topic 57 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
Speed regulation. Starting resistor limits inrush. Regenerative braking possible.
A 240 V motor with R_a=0.5 Ω at 20 A runs on E=230 V.
The next topic is "DC motor types", which builds directly on this one.
It is classed as Intermediate in Electrical Engineering (topic 58 of 106). It is an intermediate topic. Work through the beginner topics in Electrical Engineering first.
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