CN208753967U - A kind of UMDs DC bus protective device - Google Patents
A kind of UMDs DC bus protective device Download PDFInfo
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- CN208753967U CN208753967U CN201821541234.7U CN201821541234U CN208753967U CN 208753967 U CN208753967 U CN 208753967U CN 201821541234 U CN201821541234 U CN 201821541234U CN 208753967 U CN208753967 U CN 208753967U
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- 230000001681 protective effect Effects 0.000 title claims abstract description 15
- 238000001514 detection method Methods 0.000 claims abstract description 14
- 239000003990 capacitor Substances 0.000 claims description 33
- 239000003381 stabilizer Substances 0.000 claims description 21
- 230000000087 stabilizing effect Effects 0.000 claims description 11
- 230000005611 electricity Effects 0.000 claims description 7
- 238000005070 sampling Methods 0.000 claims description 6
- 238000012544 monitoring process Methods 0.000 claims description 4
- 238000007689 inspection Methods 0.000 claims description 2
- 230000000694 effects Effects 0.000 description 7
- 230000002459 sustained effect Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 230000005284 excitation Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000002093 peripheral effect Effects 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000001208 nuclear magnetic resonance pulse sequence Methods 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Abstract
The utility model provides a kind of UMDs DC bus protective device, is related to the technical field of direct current power of motor.A kind of UMDs DC bus protective device, including voltage-stabilizing output circuit, busbar voltage lower limit value detection circuit and its actuating of relay circuit and multivibrator circuit；The input terminal of the voltage-stabilizing output circuit is connected with uninterruptible power supply, and output end is connected with the input terminal in busbar voltage lower limit value detection circuit and its actuating of relay circuit and multivibrator circuit respectively；The output end of the busbar voltage lower limit value detection circuit and its actuating of relay circuit and multivibrator circuit is all connected to terminal block.UMDs DC bus protective device provided by the utility model; all built using analog circuit; it is contacted between circuit portions even closer; response speed greatly improves; strong antijamming capability; the connection of battery pack and DC bus can be disconnected after the voltage drop of DC bus end is as low as certain value, and alarm.
Description
Technical field
The utility model relates to the technical field of direct current power of motor more particularly to a kind of UMDs DC bus protection dresses
It sets.
Background technique
Often there is many dc motors and synchronous motor in industrial enterprise, and both motors are required to direct current
Source carries out excitation to it, and DC power supply is to be connected by DC bus with the excitation winding of motor.Thus protection direct current is female
The voltage value of line in a certain range, is of great significance for the normal work of motor.
For uninterrupted electric motor protecting equipment (abbreviation UMDs), its inside equally exists DC bus.And it is existing at present
UMDs lack to DC bus-bar voltage detection device so that when DC bus-bar voltage fall it is many when, system cannot
The connection for cutting off battery pack and bus in time, can not issue alarm signal and notify operator on duty, so will cause motor
Misoperation even results in the quality decline of produced product.
Utility model content
In view of the drawbacks of the prior art, the utility model provides a kind of UMDs DC bus protective device, works as DC bus
After end voltage drop is as low as certain value, disconnect DC bus with battery pack, and alarm.
A kind of UMDs DC bus protective device, comprising: voltage-stabilizing output circuit, busbar voltage lower limit value detection circuit and its
Actuating of relay circuit and multivibrator circuit；
The input terminal of the voltage-stabilizing output circuit is connected with uninterruptible power supply, and output end is examined with busbar voltage lower limit value respectively
Slowdown monitoring circuit and its actuating of relay circuit are connected with the input terminal of multivibrator circuit；The busbar voltage lower limit value detection electricity
The output end of road and its actuating of relay circuit and multivibrator circuit is all connected to terminal block.
Preferably, the voltage-stabilizing output circuit includes: transformer T1 and its current-limiting resistance R1, diode D1~D4 composition
Rectifier bridge, three groups of filter capacitors, voltage-stabiliser tube LM317T and its adjust resistance R3 and RV1, protection triode Q1 and its additional electrical
Hinder R4 and R2, protection diode D5, wire jumper JP1, three end integrated stable voltage circuit LM7805C, instruction diode (LED) 1 and its current limliting
Resistance R5；
The primary side of the transformer T1 is connected by current-limiting resistance R1 with uninterruptible power supply, and it is whole that secondary side connects diode
Flow the input terminal of bridge；The output end of the diode rectifier bridge is by first group of filter capacitor C1 and C2 and voltage-stabiliser tube in parallel
The input terminal of LM317T is connected；The output terminal of the voltage-stabiliser tube LM317T is connected to a slide rheostat RV1 and one solid
Determine valued resistor R3, the adjusting terminal of voltage-stabiliser tube LM317T is connected to a triode Q1 and its additional resistance R4 and R2, voltage-stabiliser tube
LM317T output terminal is connected by a diode D5 with second group of filter capacitor C3 and C4 in parallel；After level-one pressure stabilizing
Output voltage passes through wire jumper JP1 and third group filter capacitor C5, is connected to the input terminal of three end integrated stable voltage circuit LM7805C
Son；The output terminal of the three ends integrated stable voltage circuit LM7805C is by the 4th group of filter capacitor C6 and C7 and current limliting in parallel
Resistance R5 is connected with instruction diode (LED) 1, adjusts terminal ground；
Preferably, the busbar voltage lower limit value detection circuit and its actuating of relay circuit include: voltage sampling resistor
R6~R11, input balance resistance R12 and capacitor C8, clamp diode D6, zener diode ZD1, reference voltage adjust resistance
RV2, input balance resistance R13 and capacitor C9, voltage comparator LM258, output current limiting resistance R14, negative-feedback diode D7 and
Big resistance R15, transistor base biasing resistor R16 and R17, triode Q2, instruction diode (LED) 2 and its current-limiting resistance R18,
Alarm buzzer BZ1, relay RL1 and its sustained diode 8；
Bus end voltage is after voltage sampling resistor R6~R11 series connection, with balance resistance R12 in parallel and capacitor C8 phase
Even, then it is connected with the midpoint of clamp diode D6 and zener diode ZD1, and lead to voltage comparator from their midpoint
The negative polarity input terminal of LM258；Adjustable busbar voltage lower limit value connects by balance resistance R13 and capacitor C9 in parallel
To the positive polarity input terminal of voltage comparator LM258；The output end of the voltage comparator LM258 passes through a current-limiting resistance
After R14, the positive polarity input terminal of one group of concatenated feedback diode D7 and big resistance R15 to voltage comparator LM258 is connected；Institute
The output end current-limiting resistance R14 of voltage comparator LM258 is stated after transistor base biasing resistor R16 and R17, with triode
The base stage of Q2 is connected；The instruction diode (LED) 2 and its current-limiting resistance R18, alarm buzzer BZ1, relay RL1 and relay
The sustained diode 8 of device RL1 is connected in parallel, their one of common ends are connected with the collector of triode Q2；
Preferably, the multivibrator circuit includes: multivibrator, the transistor base being made of 555 timers
Biasing resistor R19 and R20, triode Q3；
3 feet of 555 timer pass through transistor base biasing resistor R19 and R20, the base stage phase with triode Q3
Even.
As shown from the above technical solution, the utility model has the beneficial effects that: a kind of UMDs provided by the utility model
DC bus protective device, is all built using analog circuit, and even closer, response speed is contacted between circuit portions
It greatly improves, strong antijamming capability, battery pack and DC bus can be disconnected after the voltage drop of DC bus end is as low as certain value
Connection, and alarm.Each integrated circuit modules price is more cheap simultaneously, greatly reduces manufacturing cost.
Detailed description of the invention
Fig. 1 is a kind of structural block diagram of UMDs DC bus protective device provided by the embodiment of the utility model；
Fig. 2 is the circuit structure diagram of voltage-stabilizing output circuit provided by the embodiment of the utility model；
Fig. 3 is busbar voltage lower limit value detection circuit structure diagram provided by the embodiment of the utility model；
Fig. 4 is the actuating of relay loop structure of busbar voltage lower limit value detection circuit provided by the embodiment of the utility model
Figure；
Fig. 5 is the multivibrator circuit structure chart provided by the embodiment of the utility model being made of 555 timers.
Specific embodiment
With reference to the accompanying drawings and examples, specific embodiment of the present utility model is described in further detail.Below
Embodiment is not intended to limit the scope of the present invention for illustrating the utility model.
The present embodiment is by taking certain DC bus as an example, using the UMDs DC bus protective device of the utility model, to direct current
Bus is protected.
A kind of UMDs DC bus protective device, as shown in Figure 1, comprising: voltage-stabilizing output circuit, the inspection of busbar voltage lower limit value
Slowdown monitoring circuit and its actuating of relay circuit and multivibrator circuit；
The input terminal of the voltage-stabilizing output circuit is connected with uninterruptible power supply, and output end is examined with busbar voltage lower limit value respectively
Slowdown monitoring circuit and its actuating of relay circuit are connected with the input terminal of multivibrator circuit；The busbar voltage lower limit value detection electricity
The output end of road and its actuating of relay circuit and multivibrator circuit is all connected to terminal block.
The voltage-stabilizing output circuit includes: transformer T1 and its current-limiting resistance R1, diode D1~D4 group as shown in Figure 2
At rectifier bridge, three groups of filter capacitors, voltage-stabiliser tube LM317T and its adjust resistance R3 and RV1, protection triode Q1 and its additional
Resistance R4 and R2, protection diode D5, wire jumper JP1, three end integrated stable voltage circuit LM7805C, instruction diode (LED) 1 and its limit
Leakage resistance R5.
The primary side of the transformer T1 is connected by current-limiting resistance R1 with uninterruptible power supply, and it is whole that secondary side connects diode
Flow the input terminal of bridge；The output end of the diode rectifier bridge is by first group of filter capacitor C1 and C2 and voltage-stabiliser tube in parallel
The input terminal of LM317T is connected；The output terminal of the voltage-stabiliser tube LM317T is connected to a slide rheostat RV1 and one solid
Determine valued resistor R3, the adjusting terminal of voltage-stabiliser tube LM317T is connected to a triode Q1 and its additional resistance R4 and R2, voltage-stabiliser tube
LM317T output terminal is connected by a diode D5 with second group of filter capacitor C3 and C4 in parallel；After level-one pressure stabilizing
Output voltage passes through wire jumper JP1 and third group filter capacitor C5, is connected to the input terminal of three end integrated stable voltage circuit LM7805C
Son；The output terminal of the three ends integrated stable voltage circuit LM7805C is by the 4th group of filter capacitor C6 and C7 and current limliting in parallel
Resistance R5 is connected with instruction diode (LED) 1, adjusts terminal ground.
The effect of voltage-stabilizing output circuit are as follows: one, export the continuously adjustable voltage of 1.25~37V and supplied to device peripheral circuit
Electricity；Two, by second level pressure stabilizing, instruction diode power supply is given.The method of voltage-stabilizing output circuit work are as follows: introduced first from UPS
Exchange is electrically accessed transformer primary side, and Circuit Fault on Secondary Transformer is rectified into direct current by diode rectifier bridge.The direct current passes through
Capacitor filters off AC compounent, is linked into the input terminal of voltage-stabiliser tube LM317T.The output terminal of voltage-stabiliser tube LM317T is connected to one
Slide rheostat and a fixed resistance value resistance, effect are to adjust voltage-stabiliser tube output voltage.The adjustable side of voltage-stabiliser tube LM317T
Son is connected to a triode and its additional resistance, and effect is to prevent slide rheostat movable contact contacts bad and cause pressure stabilizing
Pipe output voltage is excessive, burns out load.To an indirect diode for filter capacitor, act on is voltage-stabiliser tube LM317T output voltage
Using diode unilateral conduction, prevent filter capacitor electric discharge from burning out voltage-stabiliser tube LM317T.It can be with through filtered output voltage
It powers to device peripheral circuit, above-mentioned is level-one pressure stabilizing.Output voltage after level-one pressure stabilizing passes through wire jumper and filter capacitor, even
It is connected to the input terminal of three sections of integrated stable voltage circuit LM7805C, output voltage (5V) passes through filter capacitor and current-limiting resistance, gives
Indicate diode power supply, this is second level pressure stabilizing.
The busbar voltage lower limit value detection circuit and its actuating of relay circuit include: that voltage takes as shown in Figure 3 and Figure 4
Sample resistance R6~R11, input balance resistance R12 and capacitor C8, clamp diode D6, zener diode ZD1, reference voltage are adjusted
Resistance RV2, input balance resistance R13 and capacitor C9, voltage comparator LM258, output current limiting resistance R14, negative-feedback diode
D7 and big resistance R15, transistor base biasing resistor R16 and R17, triode Q2, instruction diode (LED) 2 and its current-limiting resistance
R18, alarm buzzer BZ1, relay RL1 and its sustained diode 8.
Bus end voltage is after voltage sampling resistor R6~R11 series connection, with balance resistance R12 in parallel and capacitor C8 phase
Even, then it is connected with the midpoint of clamp diode D6 and zener diode ZD1, and lead to voltage comparator from their midpoint
The negative polarity input terminal of LM258；Adjustable busbar voltage lower limit value is connected to electricity by balance resistance R13 and capacitor C9 in parallel
Press the positive polarity input terminal of comparator LM258；The output end of the voltage comparator LM258 after a current-limiting resistance R14,
Connect the positive polarity input terminal of one group of concatenated feedback diode D7 and big resistance R15 to voltage comparator LM258；The voltage
Base of the output end current-limiting resistance R14 of comparator LM258 after transistor base biasing resistor R16 and R17, with triode Q2
Extremely it is connected；The instruction diode (LED) 2 and its current-limiting resistance R18, alarm buzzer BZ1, relay RL1 and relay RL1
Sustained diode 8 is connected in parallel, their one of common ends are connected with the collector of triode Q2.
The effect of busbar voltage lower limit value detection circuit and its actuating of relay loop feature are as follows: when busbar voltage is lower than one
When definite value (i.e. battery voltage is lower than lower limit value), high potential, thus triode ON is presented in transistor base, indicates diode
It lights, buzzer warning, relay circuit obtains electric, contact actuation, and the bus-bar fault indicator light outside device is lighted, by outer
The continuous power loss of portion's circuit multiple groups relay, battery pack are finally cut off from DC bus.The bus end voltage that will test first
After voltage sampling resistor, one group of balance resistance capacitor is connected to ground, separately draws a clamp diode, two pole of pressure stabilizing from VDD
It manages to ground, and leads to the negative polarity input terminal of operational amplifier from their midpoint.Wherein clamp diode and zener diode
Effect be make voltage comparator negative polarity input voltage be no more than zener diode pressure stabilizing value or vdd voltage value.Secondly will
Adjustable busbar voltage lower limit value is connected to the positive polarity input terminal of amplifier by one group of balancing capacitance resistance.Voltage comparator
Output end after a current-limiting resistance, connect the anode of one group of concatenated feedback diode and big resistance to voltage comparator
Property input terminal.The effect of voltage comparator is to be compared bus sampled voltage with busbar voltage lower limit value.When voltage ratio
When high level is presented compared with device output end (bus sampled voltage is lower than busbar voltage lower limit value), the biasing resistor of transistor base
The high level can be maintained, be conducive to the reliable conducting of triode.After triode ON, instruction diode is lighted, buzzing
Device alarm, relay circuit obtain electric, contact actuation, and the bus-bar fault indicator light outside device is lighted, more by external circuit
The continuous power loss of group relay, battery pack are finally cut off from DC bus.
The multivibrator circuit includes: multivibrator, the triode base being made of 555 timers as shown in Figure 5
Pole biasing resistor R19 and R20, triode Q3；
3 feet of 555 timer pass through transistor base biasing resistor R19 and R20, the base stage phase with triode Q3
Even.
The effect of multivibrator circuit are as follows: the relay contact of the circuit shown in Fig. 4 is attracted, it will so that outside device
A certain relay electric-loss, and then its normally closed auxiliary contact is closed, so that the VCC foot of 555 timers be made to be connected to power supply, generates one group
Square-wave signal can be stopped indicator light flashing with the bus outside driving device, show that DC bus has logged out operation at this time.It is first
First by 3 foot output pulse sequences of 555 timers, which stops instruction by the bus outside triode access device
Lamp circuit.
Finally, it should be noted that above embodiments are only to illustrate the technical solution of the utility model, rather than its limitations；
Although the utility model is described in detail with reference to the foregoing embodiments, those skilled in the art should understand that:
It can still modify to technical solution documented by previous embodiment, or to some or all of the technical features
It is equivalently replaced；And these are modified or replaceed, it does not separate the essence of the corresponding technical solution, and the utility model right is wanted
Seek limited range.
Claims (4)
1. a kind of UMDs DC bus protective device, it is characterised in that: include: voltage-stabilizing output circuit, the inspection of busbar voltage lower limit value
Slowdown monitoring circuit and its actuating of relay circuit and multivibrator circuit；
The input terminal of the voltage-stabilizing output circuit is connected with uninterruptible power supply, and output end detects electricity with busbar voltage lower limit value respectively
Road and its actuating of relay circuit are connected with the input terminal of multivibrator circuit；The busbar voltage lower limit value detection circuit and
The output end of its actuating of relay circuit and multivibrator circuit is all connected to terminal block.
2. a kind of UMDs DC bus protective device according to claim 1, it is characterised in that: the pressure stabilizing exports electricity
Road includes: the rectifier bridge of transformer T1 and its current-limiting resistance R1, diode D1~D4 composition, three groups of filter capacitors, voltage-stabiliser tubes
LM317T and its adjusting resistance R3 and RV1, protection triode Q1 and its additional resistance R4 and R2, protection diode D5, wire jumper
JP1, three end integrated stable voltage circuit LM7805C, instruction diode (LED) 1 and its current-limiting resistance R5；
The primary side of the transformer T1 is connected by current-limiting resistance R1 with uninterruptible power supply, and secondary side connects diode rectifier bridge
Input terminal；The output end of the diode rectifier bridge is by first group of filter capacitor C1 and C2 and voltage-stabiliser tube LM317T in parallel
Input terminal be connected；The output terminal of the voltage-stabiliser tube LM317T is connected to a slide rheostat RV1 and a fixed resistance value
The adjusting terminal of resistance R3, voltage-stabiliser tube LM317T are connected to triode Q1 and its additional resistance R4 and R2, voltage-stabiliser tube LM317T
Output terminal is connected by a diode D5 with second group of filter capacitor C3 and C4 in parallel；Output electricity after level-one pressure stabilizing
Pressure passes through wire jumper JP1 and third group filter capacitor C5, is connected to the input terminal of three end integrated stable voltage circuit LM7805C；It is described
Filter capacitor C6 and C7 and current-limiting resistance R5 of the output terminal of three end integrated stable voltage circuit LM7805C by the 4th group of parallel connection,
It is connected with instruction diode (LED) 1, adjusts terminal ground.
3. a kind of UMDs DC bus protective device according to claim 1, it is characterised in that: the busbar voltage lower limit
Value detection circuit and its actuating of relay circuit include: voltage sampling resistor R6~R11, input balance resistance R12 and capacitor C8,
Clamp diode D6, zener diode ZD1, reference voltage adjust resistance RV2, input balance resistance R13 and capacitor C9, voltage ratio
Compared with device LM258, output current limiting resistance R14, negative-feedback diode D7 and big resistance R15, transistor base biasing resistor R16 and
R17, triode Q2, instruction diode (LED) 2 and its current-limiting resistance R18, alarm buzzer BZ1, relay RL1 and its afterflow two
Pole pipe D8；
Bus end voltage is connected after voltage sampling resistor R6~R11 series connection with balance resistance R12 and capacitor C8 in parallel,
Then it is connected with the midpoint of clamp diode D6 and zener diode ZD1, and leads to voltage comparator LM258 from their midpoint
Negative polarity input terminal；Adjustable busbar voltage lower limit value is connected to voltage ratio by balance resistance R13 and capacitor C9 in parallel
Positive polarity input terminal compared with device LM258；The output end of the voltage comparator LM258 is after a current-limiting resistance R14, connection
The positive polarity input terminal of one group of concatenated feedback diode D7 and big resistance R15 to voltage comparator LM258；The voltage compares
Base stage phase of the output end current-limiting resistance R14 of device LM258 after transistor base biasing resistor R16 and R17, with triode Q2
Even；The afterflow of the instruction diode (LED) 2 and its current-limiting resistance R18, alarm buzzer BZ1, relay RL1 and relay RL1
Diode D8 is connected in parallel, their one of common ends are connected with the collector of triode Q2.
4. a kind of UMDs DC bus protective device according to claim 1, it is characterised in that: the multivibrator returns
Road includes: multivibrator, transistor base the biasing resistor R19 and R20, triode Q3 being made of 555 timers；
3 feet of 555 timer pass through transistor base biasing resistor R19 and R20, are connected with the base stage of triode Q3.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201821541234.7U CN208753967U (en) | 2018-09-20 | 2018-09-20 | A kind of UMDs DC bus protective device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201821541234.7U CN208753967U (en) | 2018-09-20 | 2018-09-20 | A kind of UMDs DC bus protective device |
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| Publication Number | Publication Date |
|---|---|
| CN208753967U true CN208753967U (en) | 2019-04-16 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201821541234.7U Expired - Fee Related CN208753967U (en) | 2018-09-20 | 2018-09-20 | A kind of UMDs DC bus protective device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114325059A (en) * | 2022-01-10 | 2022-04-12 | 重庆三电智能科技有限公司 | High-power direct current bus detection device |
-
2018
- 2018-09-20 CN CN201821541234.7U patent/CN208753967U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114325059A (en) * | 2022-01-10 | 2022-04-12 | 重庆三电智能科技有限公司 | High-power direct current bus detection device |
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| CF01 | Termination of patent right due to non-payment of annual fee | ||
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Granted publication date: 20190416 Termination date: 20210920 |