CN115398581A

CN115398581A - DC relay

Info

Publication number: CN115398581A
Application number: CN202180027523.3A
Authority: CN
Inventors: 郭桥石; 刘建德; 贾宝华
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-05-20
Filing date: 2021-05-19
Publication date: 2022-11-25
Also published as: WO2021190672A1

Abstract

The invention relates to a direct current relay, which comprises a mechanical switch, a power supply unit, a control switch, a power supply terminal, a control terminal, a grounding terminal, an input terminal connected with the mechanical switch and an output terminal connected with the mechanical switch, wherein the control switch is a fully-controlled semiconductor switch, the power supply unit, the control switch, a ground terminal and the control terminal are connected with the control unit, an input power supply of the power supply terminal supplies power to the power supply unit, the control unit is used for detecting the voltage of the output terminal and the voltage of the input power supply, a control signal of the mechanical switch is provided by the control unit, and the input power supply is connected with the output terminal through the control switch. Has the advantages of small volume and long electric service life.

Description

DC relay

Technical Field

The invention relates to a direct current relay, in particular to a direct current relay suitable for direct current control systems of locomotives, rail transit, aviation and the like.

Background

At present, in direct current electrical control systems of locomotives, rail transit, aviation and the like, a direct current relay is generally used for carrying out frequent connection and disconnection control on each load, the defect of short electric service life of an electric contact caused by disconnection of electric arcs is overcome, and the traditional electronic arc extinguishing has the advantage of good arc extinguishing effect, but the defects of large volume and high cost are overcome.

Disclosure of Invention

The invention aims to solve the problem of large size of the existing arc extinguishing device of the direct current relay, and provides the direct current relay with the electronic arc extinguishing device, which is small in size and long in electric service life.

The purpose of the invention is achieved by the following technical scheme:

a direct current relay comprises a mechanical switch, a power supply unit, a control unit and a control switch, and further comprises a power supply terminal, a control terminal, a grounding terminal, an input terminal connected with the mechanical switch and an output terminal connected with the mechanical switch, wherein the control switch is a fully-controlled semiconductor switch, the power supply unit, the control switch, a ground terminal and the control terminal are connected with the control unit, an input power supply of the power supply terminal supplies power to the power supply unit, the control unit is used for detecting the voltage of the output terminal and the voltage of the input power supply, a control signal of the mechanical switch is provided by the control unit, and the input power supply is connected with the output terminal through the control switch.

The working principle is as follows: in the breaking process of the mechanical switch, when electric arcs are generated between contacts of the mechanical switch, the input power supply supplies power to a load connected with the output terminal through the control switch and the output terminal, and arc extinction of the mechanical switch is achieved.

The invention has the advantages of reasonable design, small volume and long electric service life.

Drawings

Fig. 1 is a schematic circuit diagram of an embodiment of a dc relay according to the present invention.

Detailed Description

Fig. 1 shows a first embodiment of the dc relay of the present invention:

a direct current relay comprises a mechanical switch K (single-pole double-throw switch), a control unit A, a power supply unit B and a control switch S1, and further comprises an input terminal J1 and an output terminal J2 (J3) which are connected with the mechanical switch K, a power supply terminal J4, a control terminal J6 and a ground terminal J5, wherein the control switch S1 is a fully-controlled semiconductor switch, the power supply unit B, the control switch S1, the ground terminal J5 and the control terminal J6 are connected with the control unit A, the input power supply of the power supply terminal J4 supplies power to the power supply unit B, the control unit A is used for detecting the voltage of the output terminal J2 (J3) and the voltage of the input power supply, a control signal of the mechanical switch K is provided by the control unit A, and the input power supply is connected with the output terminal J2 (J3) through the control switch S1; the mechanical switch K can adopt a switch without breaking force under the working condition; the input power supply is connected with the control switch S1 through the power supply unit B; the control switch S1 provides an electrical pulse to the output terminal J2 (J3); the pulse width of the electric pulse is at least more than 20 microseconds; the mechanical switch K comprises two electrical contacts; the control unit A is connected with a signal output terminal J7 and used for outputting the working state of the mechanical switch K.

The working principle is as follows: the control unit A is electrified, the voltage of the output terminal J2 (J3) and the voltage of the input power supply of the power supply terminal J4 are detected, the control unit A controls the mechanical switch K to act after inputting a control signal, and when the control unit A detects that the electric contact of the mechanical switch K is disconnected, the control switch S1 is controlled to be conducted, so that the aim of arc extinction of the mechanical switch K is fulfilled.

The control switch electrical pulse width is preferably: the time interval of the electric pulses is one time (1/2 duty ratio) or more than one time of the pulse width between 20 microseconds and 1000 microseconds, the number of the electric pulses is at least more than one, the sum of the pulse widths of the electric pulses is not less than 1 millisecond and not more than 10 milliseconds, and the action of a load R caused by false arc extinguishing pulses can be effectively prevented.

In the above embodiment, the mechanical switch K (single-pole double-throw switch) includes two electrical contacts, the control switch S1 is composed of a fully-controlled device Q1 (a triode, a field effect transistor, an IGBT, etc., an uncontrollable device D1 (a diode), and an uncontrollable device D2, and a series circuit is composed of a common anode (a common cathode and a fully-controlled device Q1 changing polarity together according to system conditions), the common node of the series circuit is connected to the fully-controlled device Q1, two ends of the series circuit are respectively connected to the two electrical contacts (2,3), and two ends of the series circuit are respectively connected to the first output terminal J2 and the second output terminal J3.

The control unit A can also be connected with a display device, and simultaneously provides electric pulse signals for loads R connected with different mechanical switches K, the common node of the fully-controlled semiconductor device, the uncontrollable device D1 (diode) and the uncontrollable device D2 can be connected with a diode, and the other end of the diode is grounded and used for inhibiting the reverse electromotive force of the loads R.

This embodiment makes things convenient for the product authentication, and through accord with safety standard, the input of switch, the high withstand voltage characteristic under the output off-state realizes the arc extinguishing to the multi-way switch of input series connection, effectively restraines the circuit inductance that the input is connected and to the overvoltage influence of arc extinguishing control switch.

In conclusion, the relay disclosed by the invention has the advantages of small volume and long electric service life.

Claims

A direct current relay is characterized in that: it includes a mechanical switch, a control unit, a power supply unit, control switch, still include power supply terminal, control terminal, ground terminal, with the input terminal that mechanical switch connects with the output terminal that mechanical switch connects, control switch is full accuse type semiconductor switch, power supply unit control switch ground terminal the control terminal with control unit connects, the input power of power supply terminal does the power supply unit power supply, control unit is used for detecting output terminal's voltage input power's voltage, mechanical switch's control signal by control unit provides, input power passes through control switch with output terminal connects.
The direct current relay according to claim 1, wherein: the mechanical switch is a switch without breaking force under working conditions.
The dc relay according to claim 1, wherein: the input power supply is connected with the control switch through the power supply unit.
The direct current relay according to claim 1, wherein: the control switch provides an electrical pulse to the output terminal.
The dc relay according to claim 4, wherein: the pulse width of the electrical pulse is between 20 microseconds and 1000 microseconds. The time interval of the electric pulses is one time or more than one time of the pulse width.
The direct current relay according to claim 5, wherein: the number of the electric pulses is at least more than one, and the sum of the pulse widths of the electric pulses is not less than 1 millisecond and not more than 10 milliseconds.
The direct current relay according to claim 1, wherein: the mechanical switch includes at least two electrical contacts.
The direct current relay according to claim 7, wherein: the mechanical switch at least comprises two electric contacts, the control switch is composed of a full-control type device and at least two uncontrollable devices, the uncontrollable devices share a cathode or a anode to form a series circuit, a common node of the series circuit is connected with the full-control type device, and two ends of the series circuit are respectively connected with the two electric contacts.
The direct current relay according to claim 8, wherein: the mechanical switch is a single-pole double-throw switch, the output terminal comprises a first output terminal and a second output terminal, and two ends of the series circuit are respectively connected with the first output terminal and the second output terminal.
The direct current relay according to claim 1, wherein: the control unit is connected with a signal output terminal and used for outputting the working state of the mechanical switch.