Electrical4U What is a DC Motor? An electric motor operated by DC (direct current) is known as a DC motor (unlike an induction motor that operates via an alternating current). A DC motor converts DC electrical energy into mechanical energy. Principle of DC Motor A DC motor produces torque when a current-carrying conductor sits in a … Read more
A DC generator converts mechanical input power into electrical output power, while a DC motor performs the reverse conversion. In either case, the output is lower than the input because some energy becomes heat, sound and air movement. The difference between input and useful output is the total loss. These losses reduce efficiency and raise … Read more
A DC motor converts DC electrical energy into mechanical rotation. This page sets out the working principle of a DC motor from a single-loop machine.The basic construction of a DC motor is a current-carrying armature fed through commutator segments and brushes. That armature sits between the north and south poles of a permanent magnet or … Read more
A DC motor is built from a stator field system and a rotor armature with a commutator and brushes. Those parts convert DC into rotation (learn about a DC motor’s working principle). A DC motor is constructed with: The stator is the stationary part. It holds the field windings and takes the supply. The rotor … Read more
The torque equation of a DC motor gives the electromagnetic torque from air-gap flux and armature current. When the machine is loaded as a motor or as a generator, rotor conductors carry current in the air-gap magnetic field. Each conductor feels a force at a common radius, so a torque appears at the rotor surface … Read more
What is an SF6 Circuit Breaker An SF6 circuit breaker is a type of circuit breaker in which sulphur hexafluoride gas or SF6 gas is used as the arc quinching medium, known as an SF6 circuit breaker. SF6 is strongly electronegative, so it captures free electrons and forms heavier negative ions with lower mobility. This … Read more
Electric Power Transmission Electric power transmission systems move bulk electrical energy from generating stations to substations near load centres. A generating station produces electrical power, while the transmission network carries it over distances that local distribution circuits do not serve. Generation and demand are often in different locations. Plant location depends on the energy source, … Read more
Corona Discharge, or the corona effect, is a localised gas discharge around an energised conductor or fitting. It begins when the surface voltage gradient makes the surrounding air ionise, but the field is not yet sufficient to form a complete arc across the insulation gap. Designers of AC and high-voltage systems control conductor geometry and … Read more
Power system stability is part of electrical engineering analysis for generation, transmission and distribution networks. The system operating point changes continually as loads, generators, controls and network connections change. Power system stability is the ability of an electric power system, from a given initial condition, to regain an operating equilibrium after a physical disturbance while … Read more
Definition of Isolator A circuit breaker interrupts load or fault current, while a disconnector provides an isolating distance and reliable position indication. Opening either device alone does not make an electrical circuit safe to touch. Maintenance also needs the authorised isolation procedure, control of every energy source, lockout or tagging, absence-of-voltage testing and protective earthing … Read more