How Magnetism Motors and Generators Works
- 4 years ago
Motor/Generators
Motor/generators are really one device that can run in two opposite modes. Contrary to what folks sometimes think, that does not mean that the two modes of the motor/generator run backward from each other (that as a motor the device turns in one direction and as a generator, it turns the opposite direction).
The shaft always spins the same way. The "change of direction" is in the flow of electricity. As a motor, it consumes electricity (flows in) to make mechanical power, and as a generator, it consumes mechanical power to produce electricity (flows out).
An AC Motor/Generator Consists of 4 Main Parts:
A shaft-mounted wire wound armature (rotor)
A field of magnets that induce electrical energy stacked side-by-side in a housing (stator)
Slip rings that carry the AC current to/from the armature
Brushes that contact the slip rings and transfer current to/from the electrical circuit
The AC Generator in Action
The armature is driven by a mechanical source of power (for example, in commercial electric power production it would be a steam turbine). As this wound rotor spins, its wire coil passes over the permanent magnets in the stator and an electric current is created in the wires of the armature.
But because each individual loop in the coil passes first the north pole then the south pole of each magnet sequentially as it rotates on its axis, the induced current continually, and rapidly, changes direction. Each change of direction is called a cycle, and it is measured in cycles-per-second or hertz (Hz).
In the United States, the cycle rate is 60 Hz (60 times per second), while in most other developed parts of the world it is 50 Hz. Individual slip rings are fitted to each of the two ends of the rotor's wire loop to provide a path for the current to leave the armature. Brushes (which are actually carbon contacts) ride against the slip rings and complete the path for the current into the circuit to which the generator is attached.
The AC Motor in Action
Motor action (supplying mechanical power) is, in essence, the reverse of generator action. Instead of spinning the armature to make electricity, current is fed by a circuit, through the brushes and slip rings and into the armature. This current flowing through the coil wound rotor (armature) turns it into an electromagnet. The permanent magnets in the stator repel this electromagnetic force causing the armature to spin. As long as electricity flows through the circuit, the motor will run.
Motor/generators are really one device that can run in two opposite modes. Contrary to what folks sometimes think, that does not mean that the two modes of the motor/generator run backward from each other (that as a motor the device turns in one direction and as a generator, it turns the opposite direction).
The shaft always spins the same way. The "change of direction" is in the flow of electricity. As a motor, it consumes electricity (flows in) to make mechanical power, and as a generator, it consumes mechanical power to produce electricity (flows out).
An AC Motor/Generator Consists of 4 Main Parts:
A shaft-mounted wire wound armature (rotor)
A field of magnets that induce electrical energy stacked side-by-side in a housing (stator)
Slip rings that carry the AC current to/from the armature
Brushes that contact the slip rings and transfer current to/from the electrical circuit
The AC Generator in Action
The armature is driven by a mechanical source of power (for example, in commercial electric power production it would be a steam turbine). As this wound rotor spins, its wire coil passes over the permanent magnets in the stator and an electric current is created in the wires of the armature.
But because each individual loop in the coil passes first the north pole then the south pole of each magnet sequentially as it rotates on its axis, the induced current continually, and rapidly, changes direction. Each change of direction is called a cycle, and it is measured in cycles-per-second or hertz (Hz).
In the United States, the cycle rate is 60 Hz (60 times per second), while in most other developed parts of the world it is 50 Hz. Individual slip rings are fitted to each of the two ends of the rotor's wire loop to provide a path for the current to leave the armature. Brushes (which are actually carbon contacts) ride against the slip rings and complete the path for the current into the circuit to which the generator is attached.
The AC Motor in Action
Motor action (supplying mechanical power) is, in essence, the reverse of generator action. Instead of spinning the armature to make electricity, current is fed by a circuit, through the brushes and slip rings and into the armature. This current flowing through the coil wound rotor (armature) turns it into an electromagnet. The permanent magnets in the stator repel this electromagnetic force causing the armature to spin. As long as electricity flows through the circuit, the motor will run.