CN2907019Y - Multi-functional current limiting protection solid-state relay - Google Patents
Multi-functional current limiting protection solid-state relay Download PDFInfo
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- CN2907019Y CN2907019Y CN 200620051416 CN200620051416U CN2907019Y CN 2907019 Y CN2907019 Y CN 2907019Y CN 200620051416 CN200620051416 CN 200620051416 CN 200620051416 U CN200620051416 U CN 200620051416U CN 2907019 Y CN2907019 Y CN 2907019Y
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Abstract
The utility model relates to a solid state relay, in particular to a solid state relay with a multifunctional current limiting protection, comprising a low pressure control and a high voltage switch, which is characterized in that a high/low voltage group indicator and a current limiting protection part are arranged on the relay, a low voltage indicator LED1, a high voltage indicator LED2, an adjustable resistance TR and a reset button AN are arranged on a relay shell; an external control power signal is received by the low voltage control part, then the state of signal power input is indicated, meanwhile, the output part of the indicator switch of the high voltage belt is driven by the internal conversion to enable the opening and closing of the solid state relay. When the high voltage loop is switched on, the high voltage loop current in output part of the indicator switch of the high voltage belt is detected by the reset protection part of the current limiting belt, when the current exceeds the set value, the low voltage belt indicator is stopped by the movement of the reset protection part of the current limiting belt, a reset button AN is arranged in the protective reset circuit, which is used to stop the protection of the controllable element in the short circuit and restore the pre-fault state.
Description
Technical field
The utility model relates to solid-state relay, refers in particular to be with multi-functional current-limiting protection formula solid-state relay.
Background technology
Existing solid-state relay load end mostly is interchange, voltage range 24V～600V, current range 0A～125A; Control end mostly is direct current, and input voltage 3V～32V is about input current 10mA.Insulation voltage 4KV, input and output isolation voltage 2.5KV.Generally form by low voltage control part and high-voltage switch gear output two parts.Low voltage control partly obtains low-voltage control signal provides stable electric current to the photoelectricity buffer circuit that is coupled by triode, photoelectricity coupling buffer circuit separates low voltage control partial circuit and high-voltage switch gear output circuit, but control signal can be flowed to the high-voltage switch gear output.The high-voltage switch gear output receives the switch controlling signal that photoelectricity coupling buffer circuit is sent here, carries out the action in switch high-pressure loop by output element (TRIAC or anti-parallel connection thyristor).Realize the function in low-voltage control signal switch high-pressure loop.The high-voltage switch gear output also has the RC circuit and piezo-resistance absorbs to make surge.The major defect of existing solid-state relay is all not have the current limliting defencive function, does not close means automatically when the permission operating current appears surpassing in the high-voltage switch gear output loop of solid-state relay, will continue this big electric current of circulation, and element causes damage in to high tension loop.Even it is also bad to add the protective device effect in the external circuit of high tension loop because the output element of solid-state relay very responsive tens of in addition tens milliseconds in can damage, general protective device can't play a protective role.Solid-state relay has not maintenanceability, must change after the damage, will cause fault recovery to postpone, and easily causes more large economy loss.
Summary of the invention
The purpose of this utility model is improved, is innovated at shortcoming that exists in the background technology and problem, and a kind of stable performance is provided, the multi-functional current-limiting protection formula solid-state relay that the life-span is long.
The technical solution of the utility model is: construct a kind of solid-state relay with current-limiting protection device; comprise low voltage control part and high-voltage switch gear part; be characterized in that the utility model is provided with high-low pressure combination indication and current limliting band reset and protection part; and on the relay housing, be provided with low pressure indicator light LED1; HT pilot LED2; adjustable resistance TR and rest button AN; wherein the current-limiting protection part is by the current limliting signal detection circuit; commutating ratio is than the value circuit; protection action output circuit and protection reset circuit are formed; described low voltage control partly receives the external control power supply signal; indicated the signal power source input, driven high pressure belt indicator cock output by internal conversion simultaneously and carry out the switch motion of solid-state relay.Current limliting band reset and protection is partly surveyed high pressure belt indicator cock output and is connected the high tension loop electric current that flows through after the high tension loop; if electric current surpasses the protection value of setting; then current limliting band reset and protection partly moves depression belt indication control section is quit work; be provided with rest button AN in the protection reset circuit; in order to the thyristor in the short circuit current make the protection stop, returning to fault actions before.
The utlity model has high life and highly reliable performance, and do not have mechanical movement structure, the contact function is finished by solid state device, and switching speed can be a Millisecond; No electromagnetic interference does not have input " coil " and contact striking and rebound, is zero voltage switch, turn-offs at the conducting of no-voltage place, zero current place, does not almost have the switching transient effect.After the protection action, use reset button can realize checking whether the fault point is got rid of, if do not get rid of, protection will be moved, if get rid of, solid-state relay will recover normal operating conditions.
Description of drawings
Fig. 1 is the utility model electricity functional-block diagram
Fig. 2 is the electrical schematic diagram of single phase poaer supply band fixed resistance and rest button and combination indicator light
Fig. 3 is the electrical schematic diagram of single phase poaer supply band adjustable resistance and rest button and combination indicator light
Fig. 4 is the electrical schematic diagram that three phase mains band fixed resistance and rest button and combination indicator light can cut off three-phase simultaneously
Fig. 5 is the electrical schematic diagram that three phase mains band adjustable resistance and rest button and combination indicator light can cut off three-phase simultaneously
Fig. 6 is three phase mains band fixed resistance and rest button and combination indicator light disengagement failure electrical schematic diagram mutually
Fig. 7 is three phase mains band adjustable resistance and rest button and combination indicator light disengagement failure electrical schematic diagram mutually
Fig. 8 is the three-phase and the one-phase relay shell schematic diagram of band LED combination indicator light and rest button
Fig. 9 is the three-phase and the one-phase relay shell schematic diagram of band LED combination indicator light, adjustable resistance TR end and rest button
Embodiment
As shown in Figure 1; the utility model comprises low voltage control part (1) and high-voltage switch gear output (2); be characterized in that the utility model is provided with the low pressure indication; high pressure indication and current limliting band reset and protection part (3); and on the relay housing, be provided with low pressure indicator light LED1; HT pilot LED2; adjustable resistance TR and rest button AN; wherein current-limiting protection part (3) is by current limliting signal detection circuit (3-1); commutating ratio is than value circuit (3-2); protection action output circuit (3-3) and protection reset circuit (3-4) are formed; described low voltage control part (1) receives the external control power supply signal; indicated the signal power source input, driven high pressure belt indicator cock output (2) by internal conversion simultaneously and carry out the switch motion of solid-state relay.Current limliting band reset and protection part (3) is surveyed high pressure belt indicator cock output (2) and is connected the high tension loop electric current that flows through after the high tension loop; if electric current surpasses the protection value of setting; then current limliting band reset and protection part (3) action quits work depression belt indication control section (1); be provided with rest button AN in the protection reset circuit (3-4); in order to the thyristor in the short circuit current make the protection stop, returning to fault actions before.
By Fig. 2 to 9 as can be known, low voltage control part described in the utility model (1) is made up of the current stabilization drive circuit (1-1) and the photoelectricity coupling buffer circuit (1-2) of band voltage stabilizing indication, the current stabilization drive circuit (1-1) of band indication links to each other with photoelectricity coupling buffer circuit (1-2), when the external control power supply signal is imported, be that direct current signal then directly uses, if AC signal then becomes direct current signal by rectification, simultaneously, the indicator light indication has the low-voltage signal input, direct current signal makes the input of photoelectricity coupling buffer circuit (1-2) receive this signal after being with the element current stabilization in the current stabilization drive circuit (1-1) of indicating, and photoelectricity coupling buffer circuit (1-2) is sent to the switch output (2) that high pressure belt is indicated with this low-tension supply signal by output.Described high-voltage switch gear output (2) comprises high voltage switch circuit (2-1), main surge absorbing circuit (2-2) and high-voltage indicating circuit (3-3), and high voltage switch circuit (2-1) mesohigh switch element or TRIAC or anti-parallel connection thyristor are connected in the output of photoelectricity coupling buffer circuit (1-2).When the output of photoelectricity coupling buffer circuit (1-2) provides signal, then make the switch element of high voltage switch circuit (2-1) carry out switch motion, main surge absorbing circuit (2-2) and high-voltage indicating circuit (2-3) all and be connected on the high voltage switch circuit (2-1), high-voltage indicating circuit (2-3) indication high tension loop has the high-tension electricity potential difference.Described current limliting band reset and protection part (3) is by current limliting signal detection circuit (3-1); commutating ratio is than value circuit (3-2); protection action output circuit (3-3) and protection reset circuit (3-4) are formed; current limliting signal detection circuit (3-1) obtains AC signal voltage by the high tension loop electric current of induction high pressure belt indicator cock output (2); this AC signal voltage is sent to commutating ratio to carry out rectification than value circuit (3-2) and becomes direct current; commutating ratio is sent to protection action output circuit (3-3) than value circuit (3-2) with this d. c. voltage signal value and compares; if this signal voltage is greater than the protection operation voltage of protecting action output circuit (3-3); then protection action output circuit (3-3) protection action; indicate the current stabilization drive circuit (1-1) of the band voltage stabilizing indication of control section (1) to close depression belt; make high pressure belt indicator cock output (2) can not get signal and quit work, protection action back protection reset circuit (3-4) makes system come back to operating state.Described protection reset circuit (3-4) comprises rest button AN and thyristor SCR31; wherein rest button AN and thyristor SCR31 are connected in parallel; by rest button AN 31 liang of terminal shortcircuits of controllable silicon SCR are no longer worked, make circuit return to initial condition.Applicable to single phase poaer supply and three phase mains, during three phase mains, the protection value that the electric current of any phase high tension loop surpass to be set can be cut off single-phase separately or three-phase cuts off simultaneously.Described whole circuit can be encapsulated in the industrial box of standard solid state relay; insulation, curing glue fire-retardant, heat conduction can be made multi-functional current-limiting protection formula solid-state relay in the filling, and wherein the box appearance is provided with LED light and adjustable resistance TR end and rest button AN.
Physical circuit of the present utility model is formed and operation principle:
Low pressure indication control section circuit: by triode Q1, Q2 LED 1, voltage stabilizing didoe WD1, WD2, resistance R 11, R12, R13, R14, R15 form the current stabilization drive circuit (1-1) of band voltage stabilizing indication; Optocoupler components IC forms photoelectricity coupling buffer circuit (1-2).After low-voltage control power carried signal to come, power supply provided an operating current for WD2, LED1 by R14, makes its voltage set up a benchmark job electrical voltage point in the amplification service area of Q2.Because Q2 is connected into emitter-base bandgap grading output, multiplication factor mainly is to follow the tracks of base voltage, improve input impedance, power output is provided for 1.(having utilized stable tube voltage drop of LED1 and good temperature-compensating here), increase electric current so that it keeps suitable brightness under free voltage by R15 when the output of control power supply LED1 brightness too low, this moment of Q2 when being 3V.The electric current that has had R15 to provide can slightly be raised the Q2 base voltage, compensate when the control input voltage is on the low side output voltage influence.When behind the stable power voltage of Q2 emitter output, its voltage by R11, R12, WD1 ground connection, the inherent voltage that has produced voltage-stabiliser tube WD1 between R12 and the WD1, this voltage in the amplification service area of Q1, set up a benchmark job electrical voltage point it and feedback resistance R13 cooperates quite as infinitely-great internal resistance source, its load current by the collector load electric current of R13 is definite, load voltage is equivalent to WD1 voltage, Q1 substantially not with the mains voltage variations quite stable, make the photo-electric control working stability.The consumption that reaches whole low power consumption control partial circuit do not increase with the control power supply and operating current strengthen, guaranteed that the caloric value of multi-functional current-limiting protection formula solid-state relay inside is very low.IC is by the while conducting when Q1 is switched on, and the IC output links to each other with high pressure indicator cock output (2 ones).LED 1 is in parallel with IC, if IC work, then LED1 work is luminous.
High pressure indicator cock output: form high voltage switch circuit (2-1) by anti-parallel connection thyristor SCR21, SCR22, resistance R 21; Resistance R 22 and capacitor C 21 or piezo-resistance are formed main surge absorbing circuit (2-2); Resistance R 23, C22, D21 and LED 2 are formed high-voltage indicating circuit (2-3).Optocoupler components IC excites interior lights electric induction when its input flows through electric current, in the output conducting that two controllable silicon SCR 21, the SCR22 of high voltage switch circuit is open-minded, and closing and opening of SCR21, SCR22 is exactly the switch motion of high tension loop.C21 and R22 form main surge absorbing circuit, when surge voltage appears in high tension loop, can absorb with the protection silicon controlled main rectifier.R23, C22, D21 and LED2 form the high pressure indication, when high tension loop has potential difference on solid-state relay, luminously provide indication.
Band combination indicator light: LED1 is bright a low pressure input, and LED2 is bright to be had the high pressure input but do not work, and LED1, LED2 are simultaneously bright, and expression current-limiting protection was moved, and needed to check to reset.
Current limliting band reset and protection part: form current limliting signal detection circuit (3-1) by current transformer TA, adjustable resistance TR (or fixed resistance R31); Resistance R 32 and bridge rectifier diode D1～D4 forms commutating ratio than value circuit (3-2); Resistance R 33, capacitor C 31 and controllable silicon SCR 31 are formed protection action output circuit (3-3).Reset button AN forms protection reset circuit (3-4).After high tension loop is opened, there is electric current to flow through in the high tension loop.Current transformer TA can produce a corresponding output current.TR (R31) is connected with TA.When TA has electric current when output, can produce at the two ends of TR (R31) one with the electric current correspondent voltage, can obtain signal voltage with the corresponding different proportion of electric current by the size of adjusting TR (R31).The signal voltage that will obtain at TR (R31) two ends flows through R32 and becomes direct-flow signal voltage at its two ends behind bridge rectifier D1～D4.Its voltage and SCR31 trigger voltage compare, and it is not open-minded to be lower than trigger voltage SCR31, and then SCR31 is open-minded to be higher than trigger voltage.R33 is connected in the SCR31 control end and plays metering function.C31 also rises at the SCR31 control end and to prevent that SCR31 from because of external interference misoperation taking place.After SCR31 is opened, formed the closed-loop path of low-voltage control power, cause the base voltage of Q1 not enough, thereby can't make the Q1 conducting, cause optocoupler components IC not have signal, the high-voltage switch gear output is closed.Reach the purpose of current-limiting protection.Reset button AN and SCR31 are connected in parallel, and after the protection action, thereby by AN SCR31 are no longer worked by short circuit, make circuit return to initial condition.Three-phase diagram is consistent with single-phase figure principle, and the use element of each phase is all identical.When being the protection action, different protection winding diagrams can allow a protection action disengagement failure phase or three-phase cut off simultaneously.Button AN is for clicking, and three-phase recovers simultaneously.
The utility model can solve former solid-state relay unprotect function and the flimsy defective of short circuit.Its circuit element can directly make an addition in original solid-state relay standard industry box.When having super setting to allow electric current to flow through in the multi-functional current-limiting protection formula solid-state relay high-voltage switch gear output loop; the current-limiting protection structure just can be moved in the one-period of electric current solid-state relay is turn-offed, and restriction output loop fault current is to reach the function of protection solid-state relay and whole high tension loop.When selecting trimmable resistance for use, the value of this fault current can on-the-spotly be adjusted, and carries out corresponding protection and adjusts.The combination of its indicator light can show whether be in malfunction, can judge the part that fault takes place by the demonstration combination of indicator light.
Embodiment described in the utility model only is the description that preferred implementation of the present utility model is carried out; be not that the utility model design and scope are limited; do not breaking away under the preceding topic of the utility model design philosophy; engineers and technicians make the technical solution of the utility model in this area various modification and improvement; all should fall into protection range of the present utility model; the technology contents that the utility model is asked for protection all is documented in claims.
Claims (7)
1; a kind of multi-functional current-limiting protection formula solid-state relay; comprise low voltage control part (1) and high-voltage switch gear output (2); it is characterized in that the utility model is provided with high-low pressure combination indication and current limliting band reset and protection part (3); and on the relay housing, be provided with low pressure indicator light LED1; HT pilot LED2; adjustable resistance TR and rest button AN; wherein current-limiting protection part (3) is by current limliting signal detection circuit (3-1); commutating ratio is than value circuit (3-2); protection action output circuit (3-3) and protection reset circuit (3-4) are formed; described low voltage control part (1) receives the external control power supply signal; indicated the signal power source input, driven high pressure belt indicator cock output (2) by internal conversion simultaneously and carry out the switch motion of solid-state relay.Current limliting band reset and protection part (3) is surveyed high pressure belt indicator cock output (2) and is connected the high tension loop electric current that flows through after the high tension loop; if electric current surpasses the protection value of setting; then current limliting band reset and protection part (3) action quits work depression belt indication control section (1); be provided with rest button AN in the protection reset circuit (3-4); in order to the thyristor in the short circuit current make the protection stop, returning to fault actions before.
2; multi-functional current-limiting protection formula solid-state relay according to claim 1; it is characterized in that described low voltage control part (1) is made up of the current stabilization drive circuit (1-1) of band voltage stabilizing indication and the photoelectricity buffer circuit (1-2) that is coupled; the current stabilization drive circuit (1-1) of band voltage stabilizing indication links to each other with photoelectricity coupling buffer circuit (1-2); when the external control power supply signal is imported; be that direct current signal then directly uses; if AC signal then becomes direct current signal by rectification; simultaneously; the indicator light indication has the low-voltage signal input; direct current signal makes the input of photoelectricity coupling buffer circuit (1-2) receive this signal after by the element current stabilization in the current stabilization drive circuit (1-1) of band voltage stabilizing indication, and photoelectricity coupling buffer circuit (1-2) is sent to high pressure belt indicator cock output (2 ones) with this low-tension supply signal by output.
3, multi-functional current-limiting protection formula solid-state relay according to claim 1; it is characterized in that described high-voltage switch gear output (2) comprises high voltage switch circuit (2-1), main surge absorbing circuit (2-2) and high-voltage indicating circuit (3-3), high voltage switch circuit (2-1) mesohigh switch element or TRIAC or anti-parallel connection thyristor are connected in the output of photoelectricity coupling buffer circuit (1-2).When the output of photoelectricity coupling buffer circuit (1-2) provides signal, the switch element of high voltage switch circuit (2-1) carries out switch motion, main surge absorbing circuit (2-2) and high-voltage indicating circuit (2-3) all and be connected on the high voltage switch circuit (2-1), high-voltage indicating circuit (2-3) indication high tension loop has the high-tension electricity potential difference.
4; multi-functional current-limiting protection formula solid-state relay according to claim 1; it is characterized in that described current limliting band reset and protection part (3) is by current limliting signal detection circuit (3-1); commutating ratio is than value circuit (3-2); protection action output circuit (3-3) and protection reset circuit (3-4) are formed; current limliting signal detection circuit (3-1) obtains AC signal voltage by the high tension loop electric current of induction high pressure belt indicator cock output (2); this AC signal voltage is sent to commutating ratio to carry out rectification than value circuit (3-2) and becomes direct current; commutating ratio is sent to protection action output circuit (3-3) than value circuit (3-2) with this d. c. voltage signal value and compares; if signal voltage is greater than the protection operation voltage of protecting action output circuit (3-3); protection action output circuit (3-3) protection action; the current stabilization drive circuit (1-1) that the band voltage stabilizing of low voltage control part (1) is indicated cuts out; make high pressure belt indicator cock output (2) can not get signal and quit work, protection action back protection reset circuit (3-4) makes system come back to operating state.
5, multi-functional current-limiting protection formula solid-state relay according to claim 1; it is characterized in that described protection reset circuit (3-4) comprises rest button AN and thyristor SCR31; wherein rest button AN and thyristor SCR31 are connected in parallel; by rest button AN 31 liang of terminal shortcircuits of controllable silicon SCR are no longer worked, make circuit return to initial condition.
6, multi-functional current-limiting protection formula solid-state relay according to claim 1; it is characterized in that applicable to single phase poaer supply and three phase mains; during three phase mains, the protection value that the electric current of any phase high tension loop surpass to be set can be cut off single-phase separately or three-phase cuts off simultaneously.
7, according to claim 1 or 2 or 3 or 4 or 5 or 6 described multi-functional current-limiting protection formula solid-state relays; it is characterized in that described whole circuit can be encapsulated in the industrial box of standard solid state relay; insulation, curing glue fire-retardant, heat conduction can be made multi-functional current-limiting protection formula solid-state relay in the filling, and wherein the box appearance is provided with LED light and adjustable resistance TR end and rest button AN.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200620051416 CN2907019Y (en) | 2006-06-18 | 2006-06-18 | Multi-functional current limiting protection solid-state relay |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200620051416 CN2907019Y (en) | 2006-06-18 | 2006-06-18 | Multi-functional current limiting protection solid-state relay |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2907019Y true CN2907019Y (en) | 2007-05-30 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200620051416 Expired - Fee Related CN2907019Y (en) | 2006-06-18 | 2006-06-18 | Multi-functional current limiting protection solid-state relay |
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| CN (1) | CN2907019Y (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109254182A (en) * | 2018-10-12 | 2019-01-22 | 山东阅芯电子科技有限公司 | The current limiting protecting method of power device dynamic test |
| CN109613373A (en) * | 2019-01-07 | 2019-04-12 | 蜂巢能源科技有限公司 | High voltage loop of electric automobile protects diagnostic system and diagnostic method and vehicle |
-
2006
- 2006-06-18 CN CN 200620051416 patent/CN2907019Y/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109254182A (en) * | 2018-10-12 | 2019-01-22 | 山东阅芯电子科技有限公司 | The current limiting protecting method of power device dynamic test |
| CN109613373A (en) * | 2019-01-07 | 2019-04-12 | 蜂巢能源科技有限公司 | High voltage loop of electric automobile protects diagnostic system and diagnostic method and vehicle |
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| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20070530 Termination date: 20100618 |