What is the throttle, and why we need it, explain simply and affordably

Hello dear visitors to my channel! In this article I want to talk to you about this important and many are not fully understood as an element of the throttle. And I try literally on fingers to explain how this mysterious radioelement functions.

What is the throttle

So, in fact the throttle - it is nothing like most conventional copper coil in most cases, wound on the ferrite or the metal core. But also the throttle can be and generally without a core.

How does he work

So, we have a choke (coil of copper wound around the core). If we begin to pass a current through it, then it starts to form an electromagnetic field around the coil. Moreover, for field-shaping need energy turns out that at the first instant of current flow it is spent on the formation of the magnetic field.

That is, roughly speaking, the first point in time choke current flow stops the flow of current through it. Once the electromagnetic field is fully formed the choke is no longer prevents current flow and it continues to move forward.

If you increase the voltage across the inductor, the current strength also increases and the throttle increases its magnetic field. Already at the outlet of the throttle voltage rise would occur with a delay, since part of the energy has been spent on the formation of an electromagnetic field.

Now let's imagine that the increase in tension had pulsed nature. Throttle it (pulse), and completely absorb the output voltage will be stable without any jumps.

This effect is widely used, for example, into a surge protector, which, thanks to the established chokes successfully filtered voltage pulse interference.

Each reactor is characterized by a current value of inductance (physical quantity characterizing properties of the magnetic circuit).

In this assertion is true: the larger the inductance of the conductor, the larger the magnetic field generated when an identical electric current value flowing.

Inductance is measured in "H" - Henry and the large inductor has a choke, the more energy you need to spend in order to fully form an electromagnetic field around it.

The more windings in the coil, the more it will have an inductance, and when placed in the core of the coil inductance increases repeatedly.

By the way, if the inductance of the inductor is sufficiently high, and high frequency current, it (throttle) quite simply completely block the flow of alternating electric current, as will simply not have enough time to saturate polarity power.

Choke in buck DC-DC converter

Cumulative effect of the electromagnetic field in the inductor is widely used in the step-down DC-DC converters, which use another very interesting throttle property, namely:

So, our reactor accumulated electromagnetic field, that's just to keep it well he does not know how it is and gives it in the form of electricity (not heat).

This occurs as follows: literally choke bombarded short pulses which are formed by transistor of the power line.

Let us follow the path of one pulse: pulse occurs in the magnitude of 12 volts, but is so short that the throttle has not time to be filled completely (until the end of the field is not formed).

After application of the pulse electric circuit and transformed already choke acts as a power source.

But since saturation was not full, it sends a voltage is not 12 volts, and a lower, for example, 5 volts.

Thus, by adjusting the pulse duration, we thereby control (increase or reduce) the voltage, which comes to the load.

Thus such pulses may be up to several thousands or even more in one second. In order to smooth the pulsation, the capacitor added to the circuit.

Choke increasing DC-DC

And now let's talk about the most interesting property of the throttle. As you probably already understand the throttle can not retain stored energy and releases it immediately. What do you think would happen if the throttle is fully saturated immediately be disconnected from the circuit?

And what happens is that the reactor would be so eager to give their charge that his findings would significantly increase the voltage to such values ​​until a breakdown air gap between the terminals throttle.

It is this unique property is used in the boost converter.

It works as follows: as long as the chain with the throttle closed, current flows quietly over a closed circuit.

But if you set the circuit breaker (usually a transistor) in the circuit, the circuit at the time of opening in the throttle pulse increase stress and if you constantly perform opening and closing, then you can shoot a high pulse voltage.

Do not forget that of the circuit has not disappeared and the power source turns out that in this case the supply voltage is summed and throttle.

conclusion

Here are such amazing properties has seemingly most ordinary throttle. If you liked this article, then we are sure to appreciate it Like and repost as well welcome in comments. Thanks for attention!