In this article you will discover Why do transformers need AC current?, Why does the transformer work in alternating current?, Why is alternating current used in transformers?
Why do transformers need AC current?
Transformers need alternating current (AC) because they operate on the principle of electromagnetic induction, which requires a changing magnetic field. Alternating current naturally provides a continuously varying magnetic field as the current changes direction, which induces a voltage in the secondary winding of the transformer.
This changing magnetic field is essential for the transfer of electrical energy between the primary and secondary coils of the transformer.
Without alternating current, there would be no variation in the magnetic field to induce a corresponding voltage in the secondary winding.
Alternating current is important because it allows for efficient transformation and transmission of voltage over long distances.
Alternating current can be easily increased to high voltages using transformers for long distance transmission, minimizing energy losses due to power line resistance. Additionally, alternating current can be easily converted back to lower voltages for safe use in homes and businesses. This versatility in voltage transformation makes AC the preferred choice for most power distribution systems.
Why does the transformer work in alternating current?
A transformer operates only with alternating current because direct current (DC) does not create a changing magnetic field.
The electromagnetic induction process, which forms the basis of transformer operation, relies on the ability of alternating current to continually change the direction and magnitude of the current. With direct current, the generated magnetic field would be constant once the current is established, resulting in no induced voltage in the secondary winding after the initial setup phase.
This lack of a changing magnetic field means that transformers cannot operate properly with direct current.
Why is alternating current used in transformers?
When direct current is used in a transformer, the initial current establishes a stable magnetic field, but because the magnetic field does not change, no additional voltage is induced in the secondary winding after the initial moment.
This constant magnetic field can also cause excessive heating in the transformer core due to continued magnetization, potentially leading to damage or overheating. The transformer would effectively behave like a short circuit under direct current conditions, causing high current flow in the primary winding and potentially causing serious electrical and thermal problems.
A transformer draws more current when there is a load on the primary side than when there is no load due to the principles of power transfer and resistance.
Under load conditions, the transformer has to supply the required power to the secondary side, which increases the primary current due to the increased power demand. In fact, the power supplied to the secondary (load) side is equal to the power drawn from the primary side, which takes into account efficiency losses.
When no load is present, the primary current is mainly the no-load current, which is relatively small and mainly used to overcome losses in the core and maintain the magnetic field.
We hope this overview for Why do transformers need AC current? made things clearer.