Find the formula for calculating the number of turns and wire diameter of the square transformer coi

The main calculation formula of transformer is as follows:

1。Transformation ratio: k=u1 u2=n1 n2 (where: k--transformer ratio, u1, u2--primary and secondary voltages, n1, n2--the number of turns of the primary and secondary windings).

2。Voltage and current relationship: u1 u2 = i2 i1 = k (i.e. u1i1 = u2i2) (where u1, u2 - primary and secondary voltages, i1, i2 primary and secondary currents).

As far as the parameters we know so far: voltage 15V, 20W, which is the secondary voltage and the power of the transformer, we will calculate it based on these two numbers.

Since the secondary current can be calculated by dividing the power by the voltage as i=p u=20 15= (approx.), then the primary current is u1 u2=i2 i1=220 15=. 66=，i1=。66=

The general calculation of transformer is to first determine the required transformer capacity to calculate the required core, and the number of primary and secondary turns of the coil to select the wire diameter.

For example, if we want a 12V voltage transformer to have a current of 2A, then the capacity of this transformer is 12*2=24VA, and then we are calculating the required core and wire diameter. To know how 20w is calculated, it is calculated according to the core and the number of turns of the line meridian magnetic flux, etc.

The current that you are talking about transformers can provide in the secondary. After deducting the loss and rectifying, there is still a current of 1A.

Easy calculation of small transformers:

Here are some examples:

1. Find the number of turns per volt.

Turns per volt = 55 core cross-section.

Your core section = square centimeters.

Therefore, the number of turns per volt = 55 turns.

2. Find the number of turns of the coil.

Primary coil n1=220 turns.

The secondary coil n2=8 can be taken as 82 turns.

The number of turns of the secondary coil is calculated to take into account the voltage drop when there is a load.

3. Find the diameter of the wire.

You didn't specify how many amps of current you require to output 8 volts? Here I assume 2 amps.

The output capacity of the transformer = 8 2 = 16 volt amperes.

The input capacity of the transformer = the output capacity of the transformer volt-ampere.

Primary coil current i1 = 20 220 = amps.

Wire diameter d=

Primary coil wire diameter d1=mm.

Secondary coil wire diameter d2=mm.

If you are stricter, please refer to the following information:

It is necessary to intensify environmental protection. Electric fish is prohibited. But I'll tell you anyway.

The E-type core must be 33*50 or more. The windings of the coil are related to the boost circuit. The boost circuit must be determined before the number of turns of the windings can be determined.

An electric fish device is actually an inverter that converts 12 V or 24 V DC into high-voltage alternating current. Not sure about the boost circuit, how to wind the transformer.