General:
The single-phase transformer includes different types of transformer (autotransformer, magnetic leakage, etc.) for very diverse uses (toys, personal protection, devices usually using batteries, discharge lamp ballast, etc.).
Most often the transformer is used to transform electrical energy into another electrical energy whose voltage is different. It is therefore impossible (just like for a motor for example) to consider the transformer as an electrical receiver. The receiver will be the device connected to the secondary of the transformer. The power and therefore the current absorbed by the primary of the transformer is therefore independent of this transformer (just as the current absorbed by a motor does not depend on the value noted on the nameplate but on the load of the motor).
Functioning :
As its name suggests, this type of transformer includes a single-phase AC power supply (primary voltage, Transformer noted U1) which supplies a coil called the primary coil. This coil is fixed on a very low reluctance magnetic field conductor whose magnetic losses are the smallest possible. The magnetic flux serves as a link between the primary and the secondary (only if the flux is not constant). The secondary consists of another coil comprising a different number of turns than that of the primary. At the terminal of this coil, a voltage is measured there (secondary voltage, denoted U2). When an impedance is connected to the secondary, a secondary current (denoted I2) flows. The secondary can be thought of as a voltage controlled voltage source.
The current in the coil of the secondary is of such a direction that it generates a magnetic flux (see relationship between current and magnetic flux) which opposes the inductor flux (thanks Mr. Lenz). The overall magnetic flux decreases which generates a modification (a decrease if I2 increases) of the value of the inductance of the primary coil. And therefore a variation (decrease) of the induction reactance and thereby of the impedance of the primary coil. If the impedance varies (decreases), the primary current also varies (increases).
General:
The single-phase transformer includes different types of transformer (autotransformer, magnetic leakage, etc.) for very diverse uses (toys, personal protection, devices usually using batteries, discharge lamp ballast, etc.).
Most often the transformer is used to transform electrical energy into another electrical energy whose voltage is different. It is therefore impossible (just like for a motor for example) to consider the transformer as an electrical receiver. The receiver will be the device connected to the secondary of the transformer. The power and therefore the current absorbed by the primary of the transformer is therefore independent of this transformer (just as the current absorbed by a motor does not depend on the value noted on the nameplate but on the load of the motor).
Functioning :
As its name suggests, this type of transformer includes a single-phase AC power supply (primary voltage, Transformer noted U1) which supplies a coil called the primary coil. This coil is fixed on a very low reluctance magnetic field conductor whose magnetic losses are the smallest possible. The magnetic flux serves as a link between the primary and the secondary (only if the flux is not constant). The secondary consists of another coil comprising a different number of turns than that of the primary. At the terminal of this coil, a voltage is measured there (secondary voltage, denoted U2). When an impedance is connected to the secondary, a secondary current (denoted I2) flows. The secondary can be thought of as a voltage controlled voltage source.
The current in the coil of the secondary is of such a direction that it generates a magnetic flux (see relationship between current and magnetic flux) which opposes the inductor flux (thanks Mr. Lenz). The overall magnetic flux decreases which generates a modification (a decrease if I2 increases) of the value of the inductance of the primary coil. And therefore a variation (decrease) of the induction reactance and thereby of the impedance of the primary coil. If the impedance varies (decreases), the primary current also varies (increases).
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