Breaker

video

A circuit breaker is typically used to get high and alternating voltage from a constant and low. This is achieved as follows.

When using a conventional switch, the current in the circuit increases slowly due to the parameters of the circuit, its current resistance. Resistance is both active and inductive, which has an inductance. If the circuit is disconnected, then as a result of electromagnetic induction, an increased voltage will appear in the inductor. The logic is that first we had voltage and current, from the law of conservation of energy the product of these quantities is constant for the source used. When we included a coil in the circuit, it was charging while the current was growing. As soon as the chain was torn, and it was done quite quickly, about 1 second of a second, everything that the coil had accumulated, from the same law of conservation of energy, it gives back to the circuit. But in this case the parameters of the circuit have changed and are determined only by the active resistance of the coil. Inductive resistance in this phase tends to zero. This is understandable, since our coil is fully charged and is the source in the circuit. Therefore, the current will tend to zero, and the voltage will increase on the contrary, but the product of these quantities will remain unnamed, except for losses. The coil acted as a "transformer" of current to voltage. The coil was pumped by current, but it gives tension.

The losses, which I mentioned above, arise in the interrupter. Since a high voltage occurs on it, the portion that arises from the separation of the contacts is pierced by this voltage, resulting in an electric arc and a loss in the creation of this arc. To avoid this, a capacitor is used. Why I use a capacitor, I will now explain. The breaker contacts have a small area. Therefore, the voltage density is high. A small contact area is needed so that the interruption time is minimal. It is not possible to increase it. Therefore, connecting the capacitor in parallel to the breaker, we thereby increase the contact area, practically without losses. The capacitor is charged, and if properly selected according to the resonant frequency of the loop oscillations, since the coil and the capacitor together form a contour, the next wave is discharged into the circuit, giving that part of the accumulated back.

The interrupter, together with the capacitor, I included in the circuit. The battery was used from a screwdriver. There are nickel-cadmium cans-10 pieces of 2.2 A and 1.2 V.
The video shows that the capacitor with its work is poor. What the reason is not known I will deal with. Sparks fly in the breaker. The frequency of interrupts can only be determined by ear, perhaps around 100 Hertz. I thought it would be smaller. Because of this, the batteries are very hot and contacts are burned in one place.
It is necessary to pick up another battery, which is not afraid of a short circuit, probably from the car, with a high starting current.
To make the breaker used parts from the relay and a piece of plywood 12mm. The capacitor is 0.5 mf at 500V. For some reason, the interrupter did not work constantly. A magnetic effort from the coil was not enough.
The principle of the mechanical breaker. One of the contacts is made of a ferromagnet (in a simple iron) material. The breaker must be located at the end of the wire magnet. When the circuit closes, the magnet wire becomes a magnet and attracts the contact from the ferromagnet. Contacts open, the magnetic field drops. Contacts are closed and everything is repeated anew. Such a breaker is used when there is not much power in the circuit. For larger capacities, electrolytic interrupters are used. Mercury or chopper of Venelt or Simon. Their design is more complex.

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