It should be noted that series compensation is used for AC transmission, which has little to do with DC transmission, and there is no DC transmission project in the country at this time, and the large-scale ultra-high voltage DC transmission project will be built for the future Sanxi power transmission.

Although everyone is familiar with AC and DC, when Zhang Yifu had not yet entered the electric hospital, he asked himself, like many people-

What exactly is alternating current? Why not direct current, which looks like a direct current?

In fact, this matter is not to blame others, but to blame the power generation principle of most of our generators, the impeller constantly rotates and cuts the magnetic inductance line to generate electricity, and such electricity is destined to be transformed. In the process of power generation, with the rotation of the magnetic field, the angle, size and even plus or minus of voltage and current are transformed in a sinusoidal with a natural frequency, and the peaks and troughs are alternating like giant breasts and hips, which is alternating current, and China's standard is 50Hz, that is, 50 times a second such a transformation, power generation and transformation equipment and transmission networks are based on this standard.

As a result, the vast majority of electrical equipment is now manufactured according to alternating current standards, and direct current is a completely different system.

And this situation is difficult to shake, because the principle of the generator is so unshakable, of course, there are also zài "playing" DC generators, in principle, it is still this set, but through guò plus some links and means, so that the export is direct current, no matter from the perspective of cost and efficiency, it is of little significance to the power generation industry.

Therefore, in this environment, almost all of the qiē around us are alternating current, and every household appliance is also designed according to 220V and 50Hz, and the principle determines the application.

It is precisely because of the principle of alternating current that it is transmitted over long distances. With the continuous change of the current in the line, a transformed magnetic field is generated in reverse, and the relationship between electricity and magnetism is always so delicate, love and kill each other.

Of course, electromagnetic induction has just begun, and this magnetic field also generates an induced current to suppress the current in the line. Although this part of the current is insignificant compared to the mainstream of power transmission, it still sacrifices some electric energy, and the longer the line, the more sacrificed, and the lower the efficiency.

This is the inductance, the biggest culprit hindering AC transmission.

Of course, the inherent resistance of copper wires in transmission lines will also cause electrical energy loss, but copper is already the most scientific and efficient choice, and there is no room for making a fuss in the existing material science category.

But in the realm of electromagnetism. We still have space.

The obstacle caused by this inductance, called inductive reactance, is the same as alternating current, and its angle and magnitude are constantly changing, sinusoidal changes, and breast-buttocks change.

So about 60 years ago, a big brother thought of another disgusting obstacle in the transmission process about this damn characteristic. Capacitors, capacitors are actually the basic principle of batteries. Two boards, with an electric field in the middle, is another complex concept, although I talked about it in high school physics, but maybe the physics teachers didn't fully understand it.

Throw away the complicated knowledge of electromagnetics in the middle, if you add capacitors to the transmission line. It will also produce something that hinders the transfer of electrical energy, which is called capacitive resistance.

Inductive reactance + capacitive reactance + copper wire resistance, brothers and children get together, and the culprits who hinder the transmission of electrical energy are all together.

After the introduction of capacitors, the guy from 60 years ago couldn't help but have a brain open. Suppose that the capacitive reactance caused by the capacitor is in an opposite state to the inductive reactance caused by the inductor, and everyone is positive, is it all honest?

The big brother with a big brain, almost without testing, thought of an amazing fact, as a little genius in physics, he immediately thought of the capacitor voltage hysteresis current of 90°, and the inductor voltage ahead of the current of 90°. A simple Sin and Cos differentiation based on fundamental electrical principles reveals this qiē.

This is simply a divine gift from the Creator, one exceeds 90 degrees, the other falls 90 degrees, and together it is just 180 degrees off, completely opposite! People hardly need to add any complicated technical means, these two brothers can naturally offset it!

It is conceivable that when the inductor voltage is at the peak of the wave, the capacitor voltage is exactly at the trough, 50 round-trips per second, it is always so coordinated, and the Creator helps you control it.

Plus, it's so easy and cheap to add capacitance to the line! It barely affects the transmission!

Therefore, the term [series compensation] was born, and series compensation is also known as reactive power compensation, because the whole process is not work, it is a kind of compensation based on the principle of electromagnetic electric field, which is equivalent to [inductance] saying that I punched you, [capacitor] said that I punched you back, and then everyone left satisfied, although no one hit anyone, but this matter was solved. On the other hand, if there is no [capacitor] verbally to accept this punch, [inductance] no one will talk about, and this punch will really be punched, and the power transmission will be lost.

Xueba also has spring, and theoretical physics can also save the world!

If it's still too abstract, you can give a less appropriate, but intuitive enough example, everyone knows that the ocean has a tidal phenomenon, that is, ocean waves, this phenomenon is due to the gravitational guidance of the moon, the satellite on our head in the process of continuous rotation, every drop of sea water has a trivial gravitational force, when they come together, it forms a tide, because the rotation of the moon is regular, so the tides are also regular, and they rise and fall regularly.

So is there a most stupid way to curb the tides without blowing up the moon and hurting Sister Chang'e?

The theory tells us, of course, that is, to recreate the moon, in the same orbit as the present moon, with the same speed and period, and along the same orbit, with the only difference that they are always on the other side of the sky, and if the rotating orbit is a circle, they must be at the point where they are always opposite.

In this way, their forces on every drop of water in the ocean are always in the opposite direction.

When the mass of this artificial moon is exactly the same as that of a standard moon, there are theoretically no tides.

I am afraid that only the Creator can do this.

Interestingly, in the electromagnetic world, the Creator is quite generous, and although he makes the inductance disgusting, he also gives you a chance to give the capacitor a chance, and if you can find the most interesting part of it, it will be a fortune.

But at the same time, how selfless the Creator is, how cruel he is. (To be continued......)