Why does the transformer maintain the establishment of the magnetic potential equilibrium under the

Why does the applied voltage determine the magnetic flux? The principle of magnetic potential equilibrium is explained by the change of primary current of the transformer from light load to heavy load.

When the primary side of the transformer applies the alternating voltage U1, and the current flowing through the primary winding of the trapped ridge is i1, the current will produce alternating magnetic flux in the iron core, so that the primary winding and the secondary winding have electromagnetic contact, according to the principle of electromagnetic induction, the alternating magnetic flux will induce electromotive force through these two windings, and its size is proportional to the maximum value of the number of winding turns and the main magnetic flux, the voltage of the side with more winding turns is high, and the voltage of this plexus on the side with fewer winding turns is low, when the secondary side of the transformer is open, that is, when the transformer is no-load, The voltage of the primary and secondary terminals is proportional to the number of turns of the primary and secondary windings, and the transformer plays the purpose of transforming the voltage. When the secondary side of the transformer is connected to the load after the infiltration, under the action of the electromotive force E2, there will be a secondary current through, and the electromotive force generated by the current will also act on the same iron core to play a reverse demagnetization role, but because the main magnetic flux depends on the power supply voltage, and U1 basically remains the same, the primary winding current will automatically increase a component to produce the magnetokinetic potential F1 to offset the magnetokinetic potential F2 generated by the secondary winding current, under the action of the primary and secondary winding currents L1 and L2, The total magnetokinetic potential acting on the core (excluding the no-load current i0), f1+f2=0, because f1=i1n1, f2=i2n2, so i1n1+i2n2=0, it can be seen from the equation that i1 and i2 are in phase, so i1 i2=n2 n1=1 k can be seen from the formula, the primary and secondary current ratio and the primary and secondary voltage ratio are the reciprocal of each other, and the primary and secondary winding power of the transformer is basically unchanged, (because the transformer's own loss is relatively smaller than its transmission power), and the size of the secondary winding current i2 depends on the needs of the loadSo the size of the primary winding current i1 also depends on the needs of the load, and the transformer plays a role in power transfer.

The difference between the excitation magnetodynamic potential of the transformer at no load and the load is that the magnetokinetic potential becomes larger at no load, while the magnetokinetic potential decreases when the load is loaded. The standard definition of magnetokinetic potential is the force of the magnetic flux generated by the flow of electric current through a conductor, and is a quantity used to measure a magnetic field or electromagnetic field, similar to the electromotive force or voltage in an electric field.

It is described as the force by which the coil can produce magnetic flux, so that scientists can use it to measure or predict the force by which the energized coil can actually excite the magnetic flux. In addition, permanent magnets also have a magnetic momentum. Note:

If the no-load current exceeds 10% of the rated current, the loss of the transformer will increase; When the no-load current exceeds 20% of the rated current, the transformer can not be used, because its temperature rise will exceed the allowable value, and the work time is slightly longer, which will lead to a burning accident.

w1*i1+w2*i2=w1*io

i1=io+(-i2*w2/w1)

In the formula, the number of turns of the original winding of the transformer is w1---.

W2--- the number of turns of the transformer's secondary winding.

i1 --- vector value of the transformer's primary winding current.

i2--- vector value of the sub-winding current of the transformer sliding exciter.

The no-load current (excitation current) of the primary winding of the IO--- transformer.

The electromotive force balance equation and description of the transformer load during the operation of the transformer load are shown in the figure below

To put it bluntly, the principle of magnetodynamic potential balance of transformer is how much is out and how much is in, and the total magnetodynamic potential is relatively stable and unchanged within a certain range!

This principle is the basis for transformers to achieve voltage transformation.

In detail, as many amperes as the primary enters, the secondary has to output as many amperes as possible. Otherwise, the transformer will saturate, collapse, and burn the switch.

When there is no load, there is almost no output in the secondary stage (there is actually one), and the primary stage only has a small no-load current (excitation current)!

The principle of transformer magnetic potential balance is: i1 * w1 + i0 * w1 = i2 * w2 (keep the main magnetic potential unchanged, the transformer can work normally.) Since the excitation potential i0*w1 generated by i0 (no-load current) is small and negligible, then there is:

i1 * W1 i2 * W2, that is, the current on the primary and secondary sides of the transformer is inversely proportional to their turns.

This is the principle of magnetic potential equilibrium and what it does.

That is, the magnetic potential generated by the primary winding is demagnetized by the negative magnetic potential generated under the load of the secondary winding, and the primary winding increases the current to increase the magnetic potential, which ensures the balance of the primary and secondary magnetic potential. The relationship is the same as its power: p1 = p2