SI25186A - An electromagnetic relay - Google Patents

Abstract

The invention describes a new construction solution for an electromagnetic relay that allows the discharge of DC currents to a size of 20 A and 1000 VDC. The electromagnetic relay was specially developed for the safe disconnection of photovoltaic modules of solar power plants and for charging stations of electric cars. When disconnecting the DC streams of such sizes, an electric arc can be created that can destroy the relay. In order to distribute the energy of the electric arc, the relays have four consecutive bound contact systems with a total contact distance of 10 mm. The relay incorporates four pairs of permanent magnets (10), which are located next to the contact systems that blow out the arc into the room - the chamber (11), where the arc extends, loses energy, and consequently goes out. The chamber (10) is formed in the longitudinal direction of the relay and has compartments (12) which interrupt the seam, thereby increasing the breakdown voltage between the contacts (7) and the contacts (9). The movable contacts (8) and fixed contact carriers (6) are designed to take advantage of the direction of the own magnetic field, which generates the switching current for an additional deviation of the arc into the chamber (11). The technical problem solved by the invention is a structural solution of an electromagnetic relay that enables the discharge of DC currents to a size of 20 A and 1000 VDC.

Description

The invention describes a new design of an electromagnetic relay, which allows disconnection of DC currents up to 20 A and 1000 Vdc. The electromagnetic relay has been specially developed for the safe disconnection of photovoltaic modules of solar power plants and for charging stations for electric cars. Solar power plants and power storage systems require switchgear for high currents and voltages. When disconnecting DC currents of such magnitude, an electric arc of up to ~ 200 mm in size can be created, and the arc itself has a temperature of more than 1000 ° C, which can melt the contact material of the rivets and destroy the relay. In order to prevent this phenomenon, we have included several series-linked open contacts in the design solution, thus increasing the contact distance, which is strictly necessary to extinguish the arc when interrupting direct current. In addition, we installed strong permanent magnets that direct the arc from the contact rivets into a special arc space where the arc expands, loses energy, and consequently extinguishes. The subject of the invention relates to the field of switching technique - electromagnetic relays.

Description of the solutions known so far

Design solutions known to us so far for electromagnetic relays are listed in patent applications EP2672497A1 and EP2533262A1.

Description of the present invention (new solution)

FIG. 1 shows a cross-section of an electromagnetic relay.

FIG. 2 shows a relay without intermediate cover (15), intermediate cover (16) and cover (17).

FIG. 3 shows a relay with a first intermediate cover (15).

FIG. 4 shows a lidless relay (17).

Electromechanical relays consist of coil (1), core (2), yoke (3), and anchor (4). An anchor (5) is attached to the anchor. The relay has four fixed contact carriers (6) with contact rivets (7) and two movable contact carriers - springs (8) with contact rivets (9).

The base of the relay is a carrier (13), which contains strong permanent magnets (10), fixed contact carriers (6), movable contact carriers (8), coil terminals (14), and an electromagnetic assembly consisting of a coil (1). , core (2), yoke (3), anchor (4) with cam (5). The carrier (13) is configured to provide space for four chambers (11) in the longitudinal direction. The first intermediate cover (15) covers the chambers (11) to protect the movable contact carriers (8) from the arc. A second intermediate cover (16) increases the insulation path between the coil (1) and the movable contact carrier (8). The relay cover (17) protects the relay against dust.

When connected to a DC source, a direct current, which results in magnetic flux, flows through the coil (1) of the relay. When the magnetic flux is large enough, the magnetic force attracts the anchor (4) to the core (2), the cam (5) pushes the spring (8) and the contact rivets (9) of the movable contact carrier (8) and the contact rivets (7) of the fixed contact carrier (6) are concluded. After the relay is switched off, the magnetic force is released, the spring (8) returns to its starting position and the contacts (7) and contacts (9) open.

It is a well-known fact that when a DC voltage is disconnected from higher voltages, an electrical arc is generated between the contacts, which can damage the fixed contact rivets (7) and the movable contact rivets (9). In order to distribute the energy of the arc, the relay has four series-coupled contact systems with a total contact distance of ~ 10 mm.

The relay incorporates four pairs of permanent magnets (10), which are located next to the contact systems that blow the cloud into the space - a chamber (11) where the cloud expands, loses energy, and consequently extinguishes.

The chamber (10) is formed in the longitudinal direction of the relay and has chambers (12) that interrupt the soot, thereby raising the breakthrough tension between the contacts (7) and the contacts (9).

The movable contacts (8) and the fixed contacts (6) are designed to take advantage of the direction of its own magnetic field generated by the switching current for additional deflection of the arc into the chamber (11).

A technical problem solved by the invention is a design solution of an electromagnetic relay that allows the disconnection of DC currents up to 20 A and 1000 Vdc.

Claims (4)

1. An electromagnetic relay is characterized by the fact that it consists of an electric magnet that generates magnetic flux, the magnetic force attaches an angle (4) to the core (2), resulting in contacts (7) and contacts (9). and strong permanent magnets (10) that deflect the cloud into the chamber (11) where the cloud expands, loses energy and subsequently extinguishes. The electromagnetic relay according to claim 1, characterized in that the arc chamber (11) is in the longitudinal direction and has chambers (12) which interrupt the rust, thereby increasing the breakthrough voltage between the contacts (7) and the contacts (9). The electromagnetic relay according to claim 1, characterized in that the movable contact carriers (8) and the fixed contact carriers (6) are designed to further exploit the direction of its own magnetic field generated by the switching current for deflection of the arc in chamber (11). 4. The electromagnetic relay according to claim 1, characterized in that the fixed contact carriers (6) and the movable contact carriers (8) and the electromagnetic assembly are attached to the same base by the support (13), thus avoiding special adjustments during the assembly phase of the product and consequently lower the cost of production.