PL154372B1 - Magnetodynamic switch of electric circuits - Google Patents

Description

THE REPUBLIC PATENT DESCRIPTION 154 372 POLAND _____ ..

OFFICE

PATENT

RP

Additional patent to patent no. Pending: 87 06 10 ( ^p . 266196) ®o hi ii s

Int. Cl. ⁵ H01H 36/00 H01H 85/30

Priority Application announced: 88 12 22

Patent description published: 1991 11 29

Creators of the invention: Albert Gmitrzak, Jan Winiarski, Józef Biliński, Henryk Sibilski

Authorized by the patent: Electrotechnical Institute, Warsaw (Poland)

Magnetodynamic switch of electrical circuits

The subject of the invention is a magnetodynamic switch of electric circuits intended for a system for testing fuses for the ability to extinguish overload currents. Its task is to switch the fuse from the low voltage circuit to the high voltage circuit.

So far, two types of systems have been used for this purpose. The first circuit is a single-circuit circuit in which the fuse is powered directly from a high power source. Current limiting resistors and chokes are connected in series with the fuse. These elements emit very high power of the order of megawatts in about one hour. It follows that such a system is relatively expensive and has large dimensions of elements, and the test itself is extremely energy-consuming. The second system is a two-circuit system, in which the fuse is powered from two energy sources - a low-voltage current source of a few volts and after the fuse blows from a second high-voltage source with a pulse power. The source switching function is performed by two medium voltage switches. This system requires a complex control system which can cause unreliable operation as well as being very expensive. Due to the long own times of the circuit breakers, the time of making the change-over is relatively long, which causes the test non-equivalent to the direct circuit.

The magnetodynamic electric circuit switch according to the invention has, on the insulating plate, a fixed contact made of a conductive material and a movable contact in the form of an aluminum plate. In the hole made in the insulating plate under the movable contact, a helically wound induction coil is mounted, which is the source of the driving force for this contact. Above this contact, there is a second fixed contact mounted on insulators, at a distance enabling the winding of the end of the movable contact during the operation of the switch.

The advantage of the switch according to the invention is a simple structure and the resulting operational reliability without the need for special control and protection methods. Another advantage is the very short duration of action not previously possible with use

154 372 other mechanical fasteners. It is also important to enable the implementation of the circuit switching function with one switch.

The switch in an exemplary embodiment is shown in the figure.

A fixed copper contact 2 and a movable contact 3 in the form of an aluminum plate are mounted in the plate 1 made of insulating material. In the hole under this contact, a spiral wound inductor 4 is mounted, which is the source of the driving force for this contact 3. Above the movable contact 3, a fixed contact 5 is mounted on an insulator not shown in the drawing at a distance enabling the winding of the end of the movable contact 3 when the switch is actuated.

The operation of the switch is as follows. Before change-over, the movable contact 3 is connected with the low-voltage fixed contact 2. Between the contacts 2 and 3, a current flows from the low-voltage LV source. Under the influence of the current impulse from the control system, the induction coil 4 creates a magnetic field which influences the eddy currents in contact 3. The resulting force repels the contact 3 causing it to short-circuit with the high-voltage fixed contact 5. In this position of contacts 3 and 5, the current flows through the fuse from the high-voltage HV source.

Claims (1)

Patent claim Magnetodynamic switch of electric circuits, characterized in that a fixed contact (2) made of a conductive material and a movable contact (3) in the form of an aluminum plate are mounted on the insulating plate (1), and in the opening made in the insulating plate (1) under the movable contact ( 3), a spiral wound induction coil (4) is mounted, which is the source of the driving force of the contact (3), over which the second fixed contact (5) is mounted on insulators at a distance enabling the winding of the end of the movable contact (3) when the switch is actuated. Department of Publishing of the UP RP. Circulation 100 copies Price: PLN 3,000