Expalin how transformers work internally with great gisualization
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A transformer is an electrical device that transfers energy between circuits using electromagnetic induction to change voltage levels. The key components include an iron core that efficiently channels magnetic fields, a primary winding where input voltage is applied, and a secondary winding where output voltage is obtained. The iron core is typically made of laminated steel to reduce energy losses.
When alternating current voltage is applied to the primary winding, an alternating current flows through the coil. This changing current creates a changing magnetic field around the primary winding. The magnetic field expands and collapses, reversing direction with the frequency of the AC input. This follows Faraday's law, where the induced voltage is proportional to the rate of change of magnetic flux.
The iron core acts as an efficient pathway, channeling almost all of the changing magnetic field directly through itself towards the secondary winding. As this changing magnetic field passes through the secondary coil, it induces an alternating voltage across the secondary terminals. The magnitude of the induced voltage depends on the turns ratio between primary and secondary windings. In this example, with 12 turns in the secondary and 8 turns in the primary, the voltage is stepped up by a factor of 1.5.
Transformers can either step up or step down voltage depending on the turns ratio. In a step-up transformer, the secondary winding has more turns than the primary, increasing the voltage. For example, 120 volts can be stepped up to 240 volts. In a step-down transformer, the secondary has fewer turns, decreasing the voltage. For instance, 240 volts can be stepped down to 12 volts. The power remains approximately constant, so when voltage increases, current decreases proportionally.
To summarize how transformers work internally: They use electromagnetic induction to transfer energy between circuits without direct connection. AC current in the primary winding creates a changing magnetic field, which the iron core efficiently channels to the secondary winding. This induces voltage in the secondary, with the voltage level determined by the turns ratio. Transformers are essential for power distribution and countless electronic applications.