CN106601549A

CN106601549A - DC relay protection control method and circuit

Info

Publication number: CN106601549A
Application number: CN201611139831.2A
Authority: CN
Inventors: 范永全; 廖建军; 李伟; 韩永炬; 刘国英
Original assignee: FARAD ELECTRIC Co Ltd
Current assignee: FARAD ELECTRIC Co Ltd
Priority date: 2016-12-12
Filing date: 2016-12-12
Publication date: 2017-04-26

Abstract

The invention discloses a DC relay protection control circuit which comprises a controller, a pulse control switching circuit, and a relay. A method adopted in the invention comprises the following steps: S1, delaying a switching control signal of a relay by a time T1, and making the two contacts of the relay switched on in a preset time T2, wherein T2>T1; and S2, when the levels of the two contacts are consistent, making the relay coil switched on/off so as to make the contacts of the relay pulled in or closed. There is no potential jitter between the contacts in the mechanical dithering process at the closing moment of the contacts of the relay. At both power-on moment and power-off moment of the relay coil, pulse is produced to make the two ends of the contacts switched on in a short time. The circuit integrates the advantages of an MOST switch and an ordinary relay contact switch. There will be no electric spark discharge. The DC relay protection control circuit of the invention is widely applicable to the technical field of electronic circuits.

Description

A kind of direct current relay protection and control method and circuit

Technical field

The present invention relates to electronic circuit technology field, more particularly to a kind of direct current relay protection and control method and circuit.

Background technology

In field of track traffic, it is higher that the relay for using mostly is voltage, and switch is frequent, when frequently switching on, conventional electricity There is electric potential difference during magnetic relay switch between contact, during contact switch, by the mechanical property of contact, 5-10mS can be produced The contact bounce time do not waited, and the shake that there is electric potential difference between this contact will cause sparking to burn out contact.As Fig. 1 contacts are moved The oscillogram of work.When solid-state relay is used, when such as tube voltage drop is big, power consumption is big after conducting, and caloric value is big, and volume is also big.

Conventional electromagnetic relay contact protection method has：Resistance-capacitance absorption loop method, coil sides simultaneously connect fly-wheel diode, line Circle side simultaneously connects diode and Zener, and using varistor the overtension of contact is prevented.Resistance-capacitance absorption loop is to apply electric capacity The principle that the voltage at two ends can not be mutated, coil sides simultaneously connect fly-wheel diode as the path of releasing winding energy, accelerate relay Release time of device etc., above method can slow down contact damage, but still there is potential in relay closed and disconnected moment Difference, still can damage contact.

By charge and discharge electro ultrafiltration pressure reduction in contact action rebound dither process can be made to diminish using resistance-capacitance absorption, but because of electricity Appearance cannot choose excessive, and when choosing excessive, electric capacity will be discharged when electric discharge by contact, cause contact secondary damage, The time of discharge and recharge is all Microsecond grade.And this is for the shake of 5-10MS, still there is electric potential difference in it, when contact is close to There is electric potential difference and will produce spark discharge and burn out contact in closure moment.

The content of the invention

In order to solve above-mentioned technical problem, it is an object of the invention to provide a kind of direct current relay protection and control method and electricity Road.

The technical solution adopted in the present invention is：A kind of direct current relay protection and control circuit, it includes controller, pulse control On-off circuit processed and relay, the controller is used for time-delay relay switch controlling signal, and to Pulse Width Control switch electricity Road exports the pulse signal of a period of time；The Pulse Width Control on-off circuit is used for according to the pulse signal for receiving, and makes described Two contacts conducting of relay.

Further, the controller includes single-chip microcomputer, ARM or FPGA.

Further, it includes that the Pulse Width Control on-off circuit includes audion or metal-oxide-semiconductor.

Present invention also offers a kind of direct current relay protection and control method, it is characterised in that it includes：

S1, enter line delay T1 for a period of time to relay switch control signal, while making the contact of relay two when default Between conducting in T2, the T2 is more than T1；

S2, when the level of two contacts it is consistent, control relay coil is turned on or off, and makes two contact adhesives of relay Or close.

The invention has the beneficial effects as follows：Before relay contact adhesive and disconnecting, controller produces the control of a period of time Pulse Width Control on-off circuit is given in pulse processed, allows two contacts of relay to turn on, and now the voltage at contact two ends is essentially identical, now Control coil turns on (disconnection), and now relay contact disconnects equal with the potential at holding contact two ends before closed action；Relay Current potential shake between contact is not produced during the mechanical shaking of device closing of contact moment；Relay coil obtains all generals of electric and dead electricity moment Produce Pulse Width Control contact two ends to turn in short-term；With reference to MOST switches with the advantage of common relay contact switch, no The situation of spark discharge occurs.

Description of the drawings

The specific embodiment of the present invention is described further below in conjunction with the accompanying drawings：

Fig. 1 is relay contact movement time, release time, bounce time and stabilization time exemplary waveform diagram；

Fig. 2 is a kind of schematic diagram of direct current relay protection and control circuit of the invention.

Specific embodiment

It should be noted that in the case where not conflicting, the feature in embodiment and embodiment in the application can phase Mutually combination.

As shown in Fig. 2 a kind of direct current relay protection and control circuit, it include controller, Pulse Width Control on-off circuit and Relay, the controller is used for time-delay relay switch controlling signal, and to Pulse Width Control on-off circuit output a period of time Pulse signal；The Pulse Width Control on-off circuit is used for according to the pulse signal for receiving, and make the relay two touch Point conducting.The controller includes A ports, B ports, C-terminal mouth and earth terminal, and the impulse controller on-off circuit includes A Port, B ports, C-terminal mouth, coil one end of the relay is grounded one end and is connected with the B ports of the controller, the control The A ports of device are used for acknowledging relay coil control signal, the C-terminal mouth of the controller and the Pulse Width Control on-off circuit C-terminal mouth connects, and the A ports and B ports of the Pulse Width Control on-off circuit are connected respectively with 2 switch contacts of the relay.

Its operation principle is：

1. when controller A end input voltages, controller C-terminal will give pulse by the pulse of 10-15mS, this pulse is produced Controlling switch circuit；

2. turn in short-term with B ends when the pulse control signal that Pulse Width Control on-off circuit receives 10-15mS will control its A end 10-15mS；

3. when A ends receive input voltage, by time delay 1-2mS by B ends output voltage driving coil, while contact-carrying is inhaled Close；

4. in the attracting process of contact, contact two ends switch adhesive, therefore contact two ends potential by Pulse Width Control Essentially identical, the mechanical shaking that now contact adhesive is produced will not bring voltage dithering between contact, therefore be not in showing for sparking As；

5. when the input of controller A ends disconnects, controller C-terminal can also produce the pulse of 10-15mS, and this pulse will give arteries and veins Rush controlling switch circuit；

6. turn in short-term with B ends when the pulse control signal that Pulse Width Control on-off circuit receives 10-15mS will control its A end 10-15mS；

7. when A ends disconnect input voltage, B ends after time delay 1-2mS are disconnected into output, relay coil dead electricity, relay Contact disconnects, and (now Pulse Width Control on-off circuit A ends close with B ends, and contact two ends potential is identical, and contact disconnects and is not in Spark phenomenon) disconnection of succeeding impulse controlling switch, contact is fully disconnected.

In the present embodiment, the controller includes single-chip microcomputer, ARM or FPGA, is loaded using single-chip microcomputer, ARM or FPGA Pulse signal produces software, and to reach generation pulse signal, pulse signal generating routine is known to the skilled person general knowledge, Here is not described in detail.

Preferred described, it is that 15MS prolongs that the controller can also design a time constant with the effect of electric capacity impulse electricity When impulse circuit.

It is further used as preferred embodiment, it includes that the Pulse Width Control on-off circuit includes audion or metal-oxide-semiconductor, The collector and emitter of the specific audion distinguishes two contacts of contact relay, and its base stage is used to receive controller output Pulse signal, mos pipe in the same manner here do not repeat.

Present invention also offers a kind of direct current relay protection and control method, it includes：

Pulse controlling switch circuit is used without the MOST switches of contact realizing in the present invention, and MOST on-off circuits are main It is to realize turning in short-term, it is ensured that in relay contact closure and in that 10-15mS time of disconnection, guard relay contact two ends are electric Gesture is essentially identical.Guarantee that basic potential-free is poor during the break-make of contact, occurs without the situation of electric discharge well, accomplish the work of contact protection With, to greatest extent extend relay contact service life.Combine the advantage of solid-state relay and electromagnetic relay, it is short When conducting if, heating can very little (this is the advantage of solid-state), can solve again electromagnetic relay contact sparking problem, can Postpone service life significantly.

It is more than that the preferable enforcement to the present invention is illustrated, but the invention is not limited to the enforcement Example, those of ordinary skill in the art can also make a variety of equivalent variations on the premise of without prejudice to spirit of the invention or replace Change, the deformation or replacement of these equivalents are all contained in the application claim limited range.

Claims

1. a kind of direct current relay protection and control circuit, it is characterised in that it include controller, Pulse Width Control on-off circuit and after Electrical equipment, the controller is used for time-delay relay switch controlling signal, and exports a period of time to Pulse Width Control on-off circuit Pulse signal；The Pulse Width Control on-off circuit is used for according to the pulse signal for receiving, and makes two contacts of the relay Conducting.

2. direct current relay protection and control circuit according to claim 1, it is characterised in that：The controller includes monolithic Machine, ARM or FPGA.

3. direct current relay protection and control circuit according to claim 1, it is characterised in that it includes that the Pulse Width Control is opened Powered-down road includes audion or metal-oxide-semiconductor.

4. a kind of direct current relay protection and control method, it is characterised in that it includes：

S1, enter line delay T1 for a period of time to relay switch control signal, while making the contact of relay two in preset time T 2 Interior conducting, the T2 is more than T1；

S2, when the level of two contacts it is consistent, control relay coil is turned on or off, and makes two contact adhesives or the pass of relay Close.