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A comparison of magnetic fields according to faradays law and hall law

Below, video of a small simple dynamo similar to the diagrams above built in the 1890s: The Generator The generator differs from the dynamo in that it produces AC power.

  • B was seen as a kind of magnetic current of vortices aligned in their axial planes, with H being the circumferential velocity of the vortices;
  • Problems include having your magnet unevenly attracted to the iron core, improper calculations of the distortion of the magnetic field the faster it spins, the more the field is distorted , spurious resistance in the armature coils, and a myriad of other potential problems.

Electrons flow in in both directions in AC power. It wasn't until the 1890s that engineers had figured out how to design powerful motors, transformers and other devices which could use AC power in a way that could compete with DC power.

  • To make a three phase generator you have to place a certain number of magnets on your stator and armature, all with proper spacing;
  • Problems include having your magnet unevenly attracted to the iron core, improper calculations of the distortion of the magnetic field the faster it spins, the more the field is distorted , spurious resistance in the armature coils, and a myriad of other potential problems;
  • Steinmetz Westinghouse Generator being constructed and tested 1905 , designed by Oliver Shallenberger, Tesla and others at Westinghouse;
  • From the 1890s until today 3 phase AC power has been the standard form of power.

While the alternator uses commutators, the generator uses a slip ring with brushes to tap the power off of the rotor. Attached to the slip ring are graphite or carbon "brushes" which are spring loaded to push the brush onto the ring.

This keeps power consistently flowing.

Generators & Dynamos

Brushes get worn down over time and need to be replaced. Below, video of slip rings and brushes, many examples from old to new: This looks different than the simple small dynamo examples you see used in teaching how the devices work. In the photo below you will see clearly one coil on the armature the rest were removed for servicing and other coils built into the stator.

From the 1890s until today 3 phase AC power has been the standard form of power. Three phases is made through the design of the generator. To make a three phase generator you have to place a certain number of magnets on your stator and armature, all with proper spacing. Electromagnetism is as complex as dealing with waves and water, so you need to know how to control the field through your design.

Generators & Dynamos

Problems include having your magnet unevenly attracted to the iron core, improper calculations of the distortion of the magnetic field the faster it spins, the more the field is distortedspurious resistance in the armature coils, and a myriad of other potential problems.

A Brief History of Dynamos and Generators: The generator evolved from work by Michael Faraday and Joseph Henry in the 1820s. Once these two inventors discovered and documented the phenomena of electromagnetic induction, it lead to experimentation by others in both Europe and North America.

He also by accident created the first alternator. He did not know what to do with the changing current, he concentrated on trying to eliminate the alternating current to get DC power, this led him to create the commutator. Electricity was still not commercially viable. A battery powered electric train from Washington DC to Baltimore failed, proving a gross embarrassment to the new field of electricity. After millions of dollars wasted steam still proved to be a better power source.

Biot–Savart law

Electricity still needed to prove to be reliable and commercially viable. He filled the magnetic field with an iron core which made a better path for magnetic flux.

Generators & Dynamos

This increased the power of the dynamo to the point were it was usable for many commercial applications. Brush Ohio developed the most efficient and reliable dynamo design ever to that point.

His inventions was sold through the Telegraph Supply Company. Brush had over 5000 arc lights in operation, representing 80 percent of all lamps world wide. The economic power of electrical age had begun. DC dynamos reign supreme in the lucrative American market, many are skeptical to invest in AC.

AC generators were powerful, however the generator alone was not the biggest problem.

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Systems for control and distribution of AC power needed to be improved before it could compete with DC on a market. Most of them used Siemens and Ferranti generators as their basis of study. William Stanley was quickly able to invent a better generator after being unsatisfied with the Siemens generator he used in his first experiment.

AC systems which include better control and powerful electric motors allow AC to compete. The three-phase generator designed by Mikhail Dolivo-Dobrovsky used at the exhibition is seen at left.

Generators & Dynamos

Steinmetz presents his paper to the AIEE on hysteresis. Steinmetz's understanding of the mathematics of AC power is published and helps revolutionize AC power system design, including large AC Generators.

  • It wasn't until the 1890s that engineers had figured out how to design powerful motors, transformers and other devices which could use AC power in a way that could compete with DC power;
  • Steinmetz presents his paper to the AIEE on hysteresis;
  • Below, video of a small simple dynamo similar to the diagrams above built in the s:

Westinghouse, Siemens, Oerlikon, and General Electric develop the world's most powerful generators. Some generators still operate 115 years later.

Steinmetz Westinghouse Generator being constructed and tested 1905designed by Oliver Shallenberger, Tesla and others at Westinghouse.