SU55153A1 - Electromagnetic high-speed non-polarized circuit breaker - Google Patents

Description

In modern high-power electrical installations of direct current with a steepness of increase of short-circuit current, estimated at tens of millions of amperes per second, the protection of circuits with high-speed circuit breakers is the most reliable.

High-speed circuit breakers protect the installation of mercury rectifiers in case of “reverse and” short circuits, while in installations with collector masks they serve as a shield against circular fire.

In all the cases listed above, so-called polarized automata are set up, i.e., they operate not only at a certain current value, but also at its well-defined direction.

In those cases when it is necessary to protect the unit from overload and from the shock of the reverse current, it is necessary to install either two automatic machines of opposite polarization or one automatic machine, but one that would react

only on the amount of current, regardless of its direction.

Known high-speed automata operating in any direction of the current and called incomplete pp 3avannymi, characterized by the fact that the speed of their work to a very small extent depends on the steepness of the current increase, while it is quite obvious (especially with the slopes mentioned above ), it would be desirable to have a protective device, the response rate of which would greatly increase with an increase in steepness.

The subject of this author's certificate is an electromagnetic high-speed unpolarized automatic switch that has all the features inherent in high-speed mechanisms (absence of latches, dogs, etc.), also with the advantage over the known ones that its speed is not due to powerful springs , but,.

mainly by the current of the protected line.

In addition to simplifying the design, the proposed automaton gives greater operating speeds depending on the current rise rate.

The essence of the invention, consisting in the special design of the magnetic core and the location of the rollers on the cores of the magnetic core, is illustrated by a schematic drawing, which shows the basic structure of the proposed switch (in the longitudinal section but the coils).

The magnetic core / is assembled from transformer iron and, in form, consists of four rods connected by a common base. The rod /// has a rectangular window that divides the rod section into two equal parts /// a and Illb.

In the upper part of the rod /// there is a hole with a sleeve and an axis 5, around which the rocker 6 can be rotated, carrying on different arms of measles 4- and 4 of type-iron.

If the sectioned holding roller 2 is supplied with voltage from a DC source with constant voltage, and the rocker 6 is turned so that the iron core 42 fits snugly to the ends of the rods /// and IV of the magnetic core, then the rocker 6 can then be loaded with force a spring of 7, which will tend to tear off the bark 4 and turn the rocker arm 6 counterclockwise. The anchor will remain at rest if the moment of force of attraction due to the holding coil 2 is greater than the moment of force of the tension spring 7 relative to the same axis of rotation 8.

The polarity of the holding coil is such that the note it creates on the drawing is directed in the rod IV from bottom to top.

From core 4-2, the flux in the rod /// splits equally along the 1Pa and Illb branches, and then again goes through the common base of the magnetic circuit into the rod. Iv. This path closes most of the stream.

The coil or turn 5 of the main current, through which the current of the protected line flows, is passed from one side through the window of the core ///, on the other hand lies between the sterile / and //.

If the current of any direction, for example, indicated in the drawing, flows along this coil 5, then as the retention pin 2 increases, the force will weaken, as the layer in the core window /// will gradually displace a part of the flow of the retaining coil into one of the parallel branches Illb (depending on the direction of the current of the circuit to be protected; in the drawing, the flow is displaced from the branch Illb to the branch Ilia), which results in saturation of the portion of the ILR, in other words, an increase in the magnetic resistance for the flow that attracts the measles 4.

Along the way, the part of coil 5 lying between the rods / and //, increasing the current passing through the coil, will create an increasing force acting on the left measles 4i, as a result of which the torque of the yoke 6 around the axis 8 will increase counterclockwise. At a certain value of the current in the protected line, the measles 2 will come off and will go to the off position, and together with the core the contacts connected to it in the usual way will be opened, which will disconnect the protected circuit.

It is possible to achieve a particular cut-off current value in any direction in many ways, for example, by tightening or unscrewing the screws 9, which causes a change in the magnetic resistance for the flow of the holding roll, or by changing the current in the holding roll.

To transfer the core from the off position to the on position, on rod IV there is a sectioned coil 5, to which the voltage from the direct current source is applied only at the moment of switching on.

During operation of the machine, the coil 5 is turned off.

Needless to say, coils 2 and 5 must act accordingly.

The airwho, spruce between the rods // and ///a is necessary so that the currents of operation of any direction are the same, since in this case the rod I, being separated from the rod /// by an air gap, does not participate in the conduction of the flow of the holding coil , but only the stream created by the tire lying between it and Sterms: it is closed to it.

The subject matter of the invention.

Electromagnetic fast-acting; unpolarized automatic switch, designed for protection of DC and AC circuits and equipped with a magnetic circuit consisting of several rods connected by a common base, on the middle of which a rotary beam is installed

A measles carrier and a movable contact of the main current circuit, characterized in that, in order to ensure the equality of the operation currents, both when the switch operates as a maximum automaton and when it operates as a reverse current automat, the flow of the retaining coil 2 is provided with a window, and the switching coil 5 is located in this window and also covers the rod // separated from the rod /// by an air gap so that some constant part of the flow created off yuchuyuschaya coil, provided the extrusion of the magnetic flux holding coil in the rod /// and thereby weakened the force holding measles 4, located on one arm of the rocker arm 6, and the other part closing through the rod /, increased the forces attracting measles 4, located on the other shoulder of the rocker. to the author's testimony A. D1 55153 I. Golubeva.

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