CN207148213U - Signal acquisition circuit, protection circuit and motor - Google Patents
Signal acquisition circuit, protection circuit and motor Download PDFInfo
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- CN207148213U CN207148213U CN201720923164.0U CN201720923164U CN207148213U CN 207148213 U CN207148213 U CN 207148213U CN 201720923164 U CN201720923164 U CN 201720923164U CN 207148213 U CN207148213 U CN 207148213U
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Abstract
The utility model discloses a kind of signal acquisition circuit, protection circuit and motor.Wherein, the signal acquisition circuit includes：Acquisition circuit is used to gather differential signal；Processor couples with acquisition circuit, and processor includes：Over-sampled converter, over-sampled converter include：Modulator and decimation filter；Wherein, modulator is used to couple the differential signal sampling of acquisition circuit collection and incremental encoding, decimation filter with modulator, and for obtaining the incremental encoding of modulator offer, incremental encoding is converted to the data signal of Linear Pulse Code Modulation.The utility model, which solves prior art, can not take into account sample frequency, signal magnitude and calculating speed so that the distorted signals in catastrophe failure and can not provide motor protection technical problem.
Description
Technical field
Circuit field is the utility model is related to, in particular to a kind of signal acquisition circuit, protection circuit and horse
Reach.
Background technology
When catastrophe failure occurs for motor, the fault current rated current more than 10 times sometimes, required in relay protection
Motor protector, using the teaching of the invention it is possible to provide fast tripping protection, tripping failure, so as to protect motor.
But existing motor protector needs to provide fast tripping protection according to ration standard, meeting rapidity and accurate
Under the conditions of property, each product protection scope and actuation time are different, and in data processing, sampled signal must is fulfilled for certain
Sample frequency and amplitude so that can tripping failure during motor failure.
Existing product is difficult to take into account sample frequency, signal magnitude and calculating speed so that in catastrophe failure, signal loses
Motor protection can not be very provided.
Sample frequency, signal magnitude and calculating speed can not be taken into account for prior art so that believed in catastrophe failure
Number distortion and the problem of motor protection can not be provided, not yet propose effective solution at present.
Utility model content
The utility model embodiment provides a kind of signal acquisition circuit, protection circuit and motor, existing at least to solve
There is technology can not take into account sample frequency, signal magnitude and calculating speed so that the distorted signals in catastrophe failure and can not carry
For the technical problem of motor protection.
According to the one side of the utility model embodiment, there is provided a kind of signal acquisition circuit, including：Acquisition circuit,
For gathering differential signal；Processor, coupled with the acquisition circuit, wherein, the processor includes：Over-sampled converter,
The over-sampled converter includes：Modulator and decimation filter, the modulator are used for the difference to acquisition circuit collection
Sub-signal is sampled and incremental encoding, and the decimation filter couples with the modulator, is carried for obtaining the modulator
The incremental encoding supplied, the incremental encoding is converted to the data signal of Linear Pulse Code Modulation.
Further, the decimation filter is used for the linear impulsive volume that the incremental encoding is converted to predetermined resolution
The data signal of code modulation.
Further, the decimation filter is used for the linear impulsive coding tune that the incremental encoding is converted to 24 bits
The data signal of system.
Further, the processor is handles the data signal using the data window of half cycles, and generation is simultaneously
Send the processor of fault-signal.
According to another embodiment of the present utility model, above-mentioned protection circuit, including above-mentioned signal acquisition electricity are additionally provided
Road, the protection circuit also include：Protector, it is connected with the processor, the failure letter sent for receiving the processor
Number, and according to the fault-signal tripping failure.
Further, the protector includes：Relay.
Further, the protector includes：Digital circuit, the digital circuit are used for the triggering in the fault-signal
Lower tripping failure.
Further, the processor is used to surpass in the data signal of N number of continuous Linear Pulse Code Modulation
In the case of crossing predetermined threshold, the fault-signal is sent to the protector.
According to another embodiment of the present utility model, a kind of motor is additionally provided, including：Motor；Above-mentioned protector, its
In, the protector is used for the failure of motor described in tripping.
Further, the normal work rotating speed of the motor is less than desired speed value.
In the utility model embodiment, by the differential signal in acquisition circuit Acquisition Circuit, then by with collection
The processor of return circuit coupling is handled differential signal, and sampling circuit is gathered using the modulator in over-sampled converter
Differential signal is sampled and incremental encoding, and the increasing of modulator offer is then obtained by the decimation filter coupled with modulator
Amount is encoded, and incremental encoding is converted to the data signal of Linear Pulse Code Modulation, so as to obtain high-resolution number
Word signal, improve sampling precision and reduce the requirement being filtered to sensor signal, sample frequency, motor signal can be taken into account
Size and calculating speed, it is ensured that motor protecting effect can be also provided in the case of motor signal distortion, solve prior art
Sample frequency, signal magnitude and calculating speed can not be taken into account so that the distorted signals in catastrophe failure and motor can not be provided
The technical problem of protection.
Brief description of the drawings
Accompanying drawing described herein is used for providing further understanding to of the present utility model, forms the part of the application,
Schematic description and description of the present utility model is used to explain the utility model, does not form to of the present utility model improper
Limit.In the accompanying drawings：
Fig. 1 is the schematic diagram according to a kind of optional signal acquisition circuit of the utility model embodiment；
Fig. 2 is the schematic diagram according to a kind of optional protection circuit of the utility model embodiment；
Fig. 3 is the schematic diagram according to a kind of optional motor of the utility model embodiment；
Fig. 4 is the schematic diagram according to a kind of signal of optional low voltage motor quick-break of the utility model embodiment；
Fig. 5 is the schematic diagram according to a kind of optional anti-saturation functional software part of the utility model embodiment.
Embodiment
In order that those skilled in the art more fully understand the utility model, it is real below in conjunction with the utility model
The accompanying drawing in example is applied, the technical scheme in the embodiment of the utility model is clearly and completely described, it is clear that be described
Embodiment is only the embodiment of the utility model part, rather than whole embodiments.Based on the reality in the utility model
Example is applied, the every other embodiment that those of ordinary skill in the art are obtained under the premise of creative work is not made, all should
When the scope for belonging to the utility model protection.
It should be noted that term " first " in specification and claims of the present utility model and above-mentioned accompanying drawing,
" second " etc. is for distinguishing similar object, without for describing specific order or precedence.It should be appreciated that so
The data used can exchange in the appropriate case, so that embodiment of the present utility model described herein can be with except at this
In diagram or description those beyond order implement.In addition, term " comprising " and " having " and their any deformation, meaning
Figure be to cover it is non-exclusive include, be not necessarily limited to clearly for example, containing a series of process of units, system, product or equipment
Those units listed to Chu, but may include not listing clearly or intrinsic for these processes, product or equipment
Other units.
Fig. 1 be according to a kind of schematic diagram of optional signal acquisition circuit of the utility model embodiment, as shown in figure 1,
The device can include：Acquisition circuit 11, for gathering differential signal；Processor 13, is coupled with acquisition circuit, wherein, processing
Device includes：Over-sampled converter 131, over-sampled converter includes：Modulator 1311 and decimation filter 1313, modulator is used for
The differential signal of acquisition circuit collection is sampled and incremental encoding, decimation filter couple with modulator, is adjusted for obtaining
The incremental encoding that device processed provides, incremental encoding is converted to the data signal of Linear Pulse Code Modulation.
According to the utility model above-described embodiment, by the differential signal in acquisition circuit Acquisition Circuit, then by with
The processor of acquisition circuit coupling is handled differential signal, and sampling circuit is adopted using the modulator in over-sampled converter
The differential signal of collection is sampled and incremental encoding, and then obtaining modulator by the decimation filter coupled with modulator provides
Incremental encoding, and incremental encoding is converted to the data signal of Linear Pulse Code Modulation, so as to obtain high-resolution
Data signal, improve sampling precision reduce the requirement being filtered to sensor signal, sample frequency, motor can be taken into account
Signal magnitude and calculating speed, it is ensured that motor protecting effect can be also provided in the case of motor signal distortion, solved existing
Technology can not take into account sample frequency, signal magnitude and calculating speed so that the distorted signals in catastrophe failure and can not provide
The technical problem of motor protection.
Alternatively, above-mentioned processor can use 16 sigma-delta type ADC CPU processor, wherein, sigma-delta type ADC bags
Include simulation sigma-delta modulator and decimation filter of digital.
As a kind of optional embodiment, decimation filter is used for the linear arteries and veins that incremental encoding is converted to predetermined resolution
Rush the data signal of coded modulation.
It is that incremental encoding is converted into predetermined resolution by decimation filter using the utility model above-described embodiment
The data signal of Linear Pulse Code Modulation, so as to which incremental encoding is converted into high-resolution Linear Pulse Code Modulation
Data signal, realize digital filtering, reduce the requirement being filtered to transducing signal.
As a kind of optional embodiment, decimation filter is used to incremental encoding being converted to the linear of 24bit24 bits
The data signal of pulse code modulation.
Using the utility model above-described embodiment, incremental encoding is converted to the linear arteries and veins of 24 bits by decimation filter
The data signal of coded modulation is rushed, the resolution ratio of signal can be improved, improves sampling precision.
As a kind of optional embodiment, processor is raw to be handled using the data window of half cycles data signal
Into and send the processor of fault-signal.
Using utility model above-described embodiment, processor is handled data signal using the data window of half cycles, can
To accelerate the speed of amplitude analysis, quickly generate fault-signal, and the fault-signal is sent, it is ensured that fast tripping protection it is fast
Speed starts.
Fig. 2 is according to a kind of schematic diagram of optional protection circuit of the utility model embodiment, as shown in Fig. 2 the guarantor
The protection circuit device can include：Above-mentioned signal acquisition circuit；And protector 21, it is connected with processor 13, for receiving area
The signal that the fault-signal that device is sent is sent is managed, and according to fault-signal tripping failure.
According to the utility model above-described embodiment, in the protection circuit, protector is connected with processor, guarantor can be passed through
Protect the fault-signal that device reception processing device is sent, and protector tripping failure controlled according to the fault-signal, and and indirect
Protector is controlled according to the motor signal of collection, so as to take into account sample frequency, motor signal size and calculating speed, it is ensured that
Motor protecting effect can be also provided in the case of motor signal distortion, sample frequency, signal can not be taken into account by solving prior art
Size and calculating speed so that the distorted signals in catastrophe failure and can not provide motor protection technical problem.
As a kind of optional embodiment, protector includes：Relay.
Using utility model above-described embodiment, relay is set in protector, can be by relay according to processor
The signal of transmission realizes the control to protection circuit, so as to carry out motor protection automatically, ensures that the rapid of fast tripping protection opens
It is dynamic.
As a kind of optional embodiment, protector includes：Digital circuit, digital circuit are used for the triggering in fault-signal
Under, tripping failure.
Using utility model above-described embodiment, digital circuit is used in protector, the failure that can be sent by processor
Signal triggers to digital circuit, the tripping failure under Digital Circuit Control, fast tripping protection circuit is entered so as to realize
Row is digital control, improves accuracy of the motor fast tripping protection circuit to breakdown judge.
As a kind of optional embodiment, processor is used for the data signal in N number of continuous linear impulsive code adjustment
In the case of exceeding threshold value, fault-signal is sent to protector.
Using utility model above-described embodiment, threshold is above in the data signal of N number of continuous linear impulsive code adjustment
In the case of value, i.e., in the case that the data of multiple sampled points exceed threshold value, assert faulty generation, and then send out to protector
Corresponding fault-signal is sent, it is low so as to be judged by the data signal of N number of continuous linear impulsive code adjustment higher than threshold value
Whether pressure motor is broken down, and the judgement of failure can be made more accurate.
Fig. 3 is according to a kind of schematic diagram of optional motor of the utility model embodiment, as shown in figure 3, the device can
With including：Motor 31；Above-mentioned protector 21, wherein, protector is used for the failure of tripping motor.
According to the utility model above-described embodiment, in motor, motor is connected by protector, event can occur in motor
In the case of barrier, by the failure of protector tripping motor, so as to protect motor, the protection to motor is realized.
As a kind of optional embodiment, the normal work rotating speed of motor is less than desired speed value.
Using the utility model above-described embodiment, motor judges electricity in the case where working speed is less than desired speed value
Machine normal work；Judge that the working condition of motor breaks down in the case where motor speed is higher than desired speed value, start horse
Up to fast tripping protection, so as to protect the safety of motor.
The utility model additionally provides a kind of preferred embodiment, and the preferred embodiment provides a kind of low voltage motor quick-break and protected
The anti-saturation function of shield.
The utility model provides a kind of wide scope, the data processing method of high-precision anti-saturation so that during catastrophe failure
Signal is undistorted, and reliably protecting is provided to motor.
Fig. 4 is according to a kind of schematic diagram of the signal of optional low voltage motor quick-break of the utility model embodiment, such as Fig. 4
Shown, the oscillogram of the signal of low voltage motor quick-break under normal operating conditions is sine curve.
Alternatively, during motor catastrophe failure, the mutation of fault-signal amplitude, (it is unsatisfactory for once current transformer scope is too small
It is more than 10 times of rated current), distorted signals when will cause failure (saturation, waveform disappear top), now as still entered according to normal waveform
Row analysis calculates, and can not correctly be identified when may result in failure and damage protection object-based device.
Alternatively, the achievement unit of anti-saturation function provided by the utility model point includes：Hardware components, software function are calculated
Method.
In hardware components, the signal acquisition core of low voltage motor fast tripping protection is on signal acquisition circuit, current main-stream CPU
ADC Analog-digital Converters be 3V reference sources, 12bit digital conversion results, the range of signal of collection is wider, signal resolution
Smaller, sampling precision is more difficult to ensure.
Alternatively, technical scheme provided by the utility model can be selected at a kind of CPU with 24 sigma-delta type ADC
Manage device and carry out signal acquisition, improve the resolution ratio of signal, improve sampling precision, meanwhile, acquisition circuit is inputted using differential signal
Carry out signal acquisition.
It should be noted that ∑-Δ type ADC is also known as over-sampled converter, it is before using incremental encoding mode
The size of the difference of one value and latter value carries out quantization encoding.∑-Δ type ADC includes simulation sigma-delta modulator sum
Word decimation filter.Sigma-delta modulator mainly completes signal sampling and incremental encoding, and it provides increment to decimation filter of digital
Coding is ∑-Δ code；Decimation filter of digital completes the filtering extraction to ∑-Δ code, and incremental encoding is converted into high-resolution
Linear Pulse Code Modulation data signal.Therefore decimation filter is effectively equivalent to a code pattern converter.
By the utility model above-described embodiment, the signal of low voltage motor fast tripping protection is gathered by ∑-Δ type ADC, can
Make the resolution ratio of collection signal higher with volume, up to 24；The switching rate of low voltage motor is higher, can be higher than integral form and pressure
Frequency changing type ADC；And ∑-Δ type ADC price is low；∑-Δ type ADC high frequency multiplication the oversampling technique of inner utilization, realize
Digital filtering, reduces the requirement being filtered to sensor signal.
It should be noted that it is that, by controlling " benchmark " voltage, can be easy to using first benefit of differential signal
Ground identifies less signal.With " " in the system of the single ended signaling scheme that does benchmark, the exact value of measurement signal relies on system
In system " " uniformity.Signal source and signal receiver distance are more remote, the part of low voltage motor fast tripping protection " " voltage
Discrepant possibility is bigger between value.From differential signal recover signal value largely with " " exact value without
Close, and within a certain range.Second key benefit of differential signal is that Difference signal pair external electromagnetic interference (EMI) is high
What degree was immunized.Influence to one almost identical degree of interference source every one end of Difference signal pair.Since voltage differences determine signal
Value, will so it ignore any same interference occurred on two conductors.Except less sensitive outer to disturbing, differential signal is than singly
The EMI of end signal generation will also lack.The 3rd benefit that differential signal provides is, being capable of essence calmly in a single supply system
Really handle " bipolar " signal.It is single-ended in order to handle, " bipolar " signal of single supply system, it is necessary between ground and electrical mains
At certain free voltage (be typically midpoint) establish a void " ".With higher than it is empty " " voltage represent positive signal, be less than
It is empty " " voltage represent negative signal.Next, virtual earth must be correctly distributed in whole system.And for difference
Signal, it is not necessary to it is such a it is empty " ", this just makes processing and propagates " bipolar " signal to have a high-true, and need not rely on empty
" " stability.
Fig. 5 is according to a kind of schematic diagram of optional anti-saturation functional software part of the utility model embodiment, such as Fig. 5
It is shown, gather per phase current information of voltage, smoothing processing is done to sample point data, judges whether electric current has mutation, is had in electric current
In the case of mutation, continuous multipoint mutation is judged whether, if in the presence of continuous multipoint mutation, with half cycles calculating current width
Value, is not mutated in electric current, or electric current has mutation but judges whether to reach timing ga(u)ge in the case of multipoint mutation is not present
Evaluation time, if reaching timing ga(u)ge evaluation time, with whole wave calculating current amplitude, if not reaching timing ga(u)ge evaluation time, Huo Zheyong
Whole wave calculating current amplitude, and with half cycles calculating current amplitude in the case of, judge amplitude whether exceed protection setting
Value, if more than protection setting value, trip protection, then terminate；If amplitude directly terminates not less than protection setting value.
1st, a cycle (the cycle 20mS of sine wave one, sample 48 points), due to being differential signal, sample point data has filtered
Common mode interference signal, data processing are more many soon than single ended data acquisition process speed.
2nd, monitoring sample point data change is implemented in sampling process, when setting data are mutated threshold value as catastrophe failure
Basis for estimation, when continuous 6 sample point datas exceed threshold value, it is believed that truly have failure, now the meter of current amplitude
Calculation is no longer dependent on timing sampling calculating, but starts amplitude analysis immediately, to ensure quick, the data of calculating of fast tripping protection
Window no longer takes whole wave (20mS) computational methods, but uses the data window of half cycles, is calculated with half cycle Fu's formula algorithm
Amplitude.
3rd, once amplitude starts output and sends trip command disengagement failure electric current immediately more than the fault threshold values set,
Protect motor.
The utility model above-described embodiment, precision transformers more than 10 times of rated current can be used to carry out data and adopted
Collection.
The utility model above-described embodiment, sample frequency (one week 48 point sampling), data-signal size can be taken into account simultaneously
(16 ∑s-Δ differential signal), data processing speed (half weekly data).
The utility model above-described embodiment, data mutational formats can be used to start fast tripping protection.
, can be wider than the protection domain of general motor fast tripping protection device using the utility model above-described embodiment, tight
Can be by fast tripping protection tripping failure in the case of weight failure, rather than wait higher level's protection equipment to trip, so as to reduce
Failure face.
Above-mentioned the utility model embodiment sequence number is for illustration only, does not represent the quality of embodiment.
In above-described embodiment of the present utility model, the description to each embodiment all emphasizes particularly on different fields, in some embodiment
The part not being described in detail, it may refer to the associated description of other embodiment.
In several embodiments provided herein, it should be understood that disclosed technology contents, others can be passed through
Mode is realized.Wherein, device embodiment described above is only schematical, such as the division of the unit, Ke Yiwei
A kind of division of logic function, can there is an other dividing mode when actually realizing, for example, multiple units or component can combine or
Person is desirably integrated into another system, or some features can be ignored, or does not perform.Another, shown or discussed is mutual
Between coupling or direct-coupling or communication connection can be INDIRECT COUPLING or communication link by some interfaces, unit or module
Connect, can be electrical or other forms.
The unit illustrated as separating component can be or may not be physically separate, show as unit
The part shown can be or may not be physical location, you can with positioned at a place, or can also be distributed to multiple
On unit.Some or all of unit therein can be selected to realize the purpose of this embodiment scheme according to the actual needs.
In addition, each functional unit in each embodiment of the utility model can be integrated in a processing unit,
Can be that unit is individually physically present, can also two or more units it is integrated in a unit.It is above-mentioned integrated
Unit can both be realized in the form of hardware.
Described above is only preferred embodiment of the present utility model, it is noted that for the common skill of the art
For art personnel, on the premise of the utility model principle is not departed from, some improvements and modifications can also be made, these improve and
Retouching also should be regarded as the scope of protection of the utility model.
Claims (10)
- A kind of 1. signal acquisition circuit, it is characterised in that including：Acquisition circuit, for gathering differential signal；Processor, coupled with the acquisition circuit, wherein, the processor includes：Over-sampled converter, the over-sampling conversion Device includes：Modulator and decimation filter, the modulator are used to be sampled the differential signal of acquisition circuit collection And incremental encoding, the decimation filter couple with the modulator, compiled for obtaining the increment that the modulator provides Code, the incremental encoding is converted to the data signal of Linear Pulse Code Modulation.
- 2. signal acquisition circuit according to claim 1, it is characterised in that the decimation filter is used for the increment Code conversion is the data signal of the Linear Pulse Code Modulation of predetermined resolution.
- 3. signal acquisition circuit according to claim 2, it is characterised in that the decimation filter is used for the increment Code conversion is the data signal of the Linear Pulse Code Modulation of 24 bits.
- 4. signal acquisition circuit according to claim 1, it is characterised in that the processor is the data using half cycles Window is handled the data signal, generates and sends the processor of fault-signal.
- 5. a kind of protection circuit, it is characterised in that described including the signal acquisition circuit any one of Claims 1-4 Protection circuit also includes：Protector, it is connected with the processor, the fault-signal sent for receiving the processor, and is believed according to the failure Number tripping failure.
- 6. protection circuit according to claim 5, it is characterised in that the protector includes：Relay.
- 7. protection circuit according to claim 5, it is characterised in that the protector includes：Digital circuit, the numeral Circuit is used for the tripping failure under the triggering of the fault-signal.
- 8. protection circuit according to claim 5, it is characterised in that the processor is used in N number of continuous line Property pulse code modulation data signal exceed predetermined threshold in the case of, send the fault-signal to the protector.
- A kind of 9. motor, it is characterised in that including：Motor；Protector any one of claim 5 to 8, wherein, the protector is used for the failure of motor described in tripping.
- 10. motor according to claim 9, it is characterised in that the normal work rotating speed of the motor is less than desired speed Value.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720923164.0U CN207148213U (en) | 2017-07-27 | 2017-07-27 | Signal acquisition circuit, protection circuit and motor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720923164.0U CN207148213U (en) | 2017-07-27 | 2017-07-27 | Signal acquisition circuit, protection circuit and motor |
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| Publication Number | Publication Date |
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| CN207148213U true CN207148213U (en) | 2018-03-27 |
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| CN201720923164.0U Active CN207148213U (en) | 2017-07-27 | 2017-07-27 | Signal acquisition circuit, protection circuit and motor |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107422177A (en) * | 2017-07-27 | 2017-12-01 | 北京德威特继保自动化科技股份有限公司 | Signal acquisition circuit and method, protection circuit and method and motor |
-
2017
- 2017-07-27 CN CN201720923164.0U patent/CN207148213U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107422177A (en) * | 2017-07-27 | 2017-12-01 | 北京德威特继保自动化科技股份有限公司 | Signal acquisition circuit and method, protection circuit and method and motor |
| CN107422177B (en) * | 2017-07-27 | 2020-10-09 | 北京德威特电气科技股份有限公司 | Signal acquisition circuit and method, protection circuit and method, and motor |
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Address after: 101300 1, 1 yuan 17, Juyuan Road, Mapo Town, Shunyi District, Beijing. Patentee after: Beijing DeWitt electric Polytron Technologies Inc Address before: 101300 1, 1 yuan 17, Juyuan Road, Mapo Town, Shunyi District, Beijing. Patentee before: Beijing Devote Relay Protection Technology Co., Ltd. |