CN102262178B - Voltage detecting and measuring circuit and detection and the method for measurement input AC voltage - Google Patents
Voltage detecting and measuring circuit and detection and the method for measurement input AC voltage Download PDFInfo
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- CN102262178B CN102262178B CN201110146661.1A CN201110146661A CN102262178B CN 102262178 B CN102262178 B CN 102262178B CN 201110146661 A CN201110146661 A CN 201110146661A CN 102262178 B CN102262178 B CN 102262178B
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- 239000004020 conductor Substances 0.000 claims description 18
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Abstract
A kind of voltage detecting and measuring circuit are provided.This circuit includes being operatively coupled to the first Zener diode of AC power input line and being operatively coupled to the second Zener diode of reference voltage line.First and second Zener diodes are configured to transmit the part of the input AC voltage from AC power input line to produce output waveform.This circuit also includes: photo-coupler, and it coupled to the first and second Zener diodes with reception from the output waveform of the first and second Zener diodes, inputs AC voltage with detection；Processing circuit, it is configured to receive the output waveform from photo-coupler, and determines the size of input AC voltage based on this output waveform；And control circuit, it is configured to size based on input voltage and controls the voltage of at least one electrical equipment.Each breakdown voltage of the first and second Zener diodes is adjusted to distinguish multiple input voltage.
Description
Technical field
The present invention relates generally to control system, particularly for voltage detecting and the measurement of this system
Circuit.
Background technology
For the electric power electrical apparatus used in such as industrial automation and control system, exist a variety of
Power supply.Electrical equipment can suffer from the multiple different power supply voltage level from power supply.Such as, exist
Different geographic regions in the world, supply voltage may be dramatically different.Additionally, voltage can be according to difference
Rated power supply value and different.
Generally it is desirable that detect the existence of input voltage while power supply is connected to electrical equipment.This
Outward, the size measuring the input voltage for configuring electrical equipment is useful.
A kind of mode of detection input voltage is to pass through isolating transformer.But, isolation voltage device may
Costly, and may not provide for control electrical equipment voltage required by input voltage size
Accurate measurement.
Therefore, it is intended that develop a kind of size that can automatically detect input voltage and this voltage of measurement
Voltage detecting and the system of measurement.
Summary of the invention
In simple terms, according to one embodiment of present invention, it is provided that a kind of voltage detecting and measuring circuit.
This circuit includes the first Zener diode being operatively coupled to AC power input line and is operatively coupled to
Second Zener diode of reference voltage line.First and second Zener diodes be configured to transmit from
The part of the input AC voltage of AC power input line is to produce output waveform.This circuit also includes:
Photo-coupler, it coupled to the first and second Zener diodes to receive from the first and second Zeners two
The output waveform of pole pipe, with detection input AC voltage；Processing circuit, it is configured to receive from light
The output waveform of bonder, and the size of input AC voltage is determined based on this output waveform；And
Control circuit, it is configured to size based on input voltage and controls the electricity of at least one electrical equipment
Pressure.Each breakdown voltage of the first and second Zener diodes is adjusted to distinguish multiple input electricity
Pressure.
According on the other hand, it is provided that a kind of detection and the method measuring input AC voltage.The method bag
Include and apply input AC voltage to multiple Zener diodes, and transmission inputs exceeding together of AC voltage
Receive diode breakdown voltage part with to photo-coupler provide output waveform.The feature of output waveform
Depend on the size of input voltage.The method also includes that the output processing photo-coupler is to detect input
AC voltage and estimate input voltage size, size based on estimated input voltage control to
A few electrical equipment, and the breakdown voltage of regulation Zener diode is to distinguish multiple input AC electricity
Pressure.
According on the other hand, it is provided that a kind of voltage detecting and measuring circuit.This circuit includes AC electric power
Input conductor and the first and second Zener diodes, the first and second Zener diodes coupled to AC
Electric power input conductor and be configured to transmit the input AC voltage from AC electric power input conductor
Part is to produce output waveform.This circuit includes the optical coupling coupleding to the first and second Zener diodes
Device.Photo-coupler is configured to receive the output waveform from the first and second Zener diodes.This electricity
Road includes the multiple resistors being arranged between AC electric power input conductor and photo-coupler.These resistance
Device is configured to limit by photo-coupler and the electric current of the first and second Zener diodes.This circuit is also
Including processing circuit, this process circuit is configured to the process output waveform from photo-coupler with detection
Multiple input voltage waveforms on input voltage signal and/or differentiation AC electric power input conductor；And
Control circuit, it is configured to size based on input AC voltage and controls at least one electrical equipment
Voltage.Wherein, each breakdown voltage of the first and second Zener diodes be adjusted to distinguish many
Individual input voltage waveform.
Accompanying drawing explanation
May be better understood when reading detailed further below referring to the drawings the present invention these and its
Its feature, aspect and advantage, reference similar in whole accompanying drawings represents similar parts.
Fig. 1 illustrates the system with voltage detecting and measuring circuit according to each side of the present invention.
Fig. 2 illustrates the system of voltage detecting and the measuring circuit with the Fig. 1 according to each side of the present invention
Example arrangement.
Fig. 3 illustrates have the voltage detecting by Fig. 1 and the corresponding output voltage waveforms of measuring circuit generation
Example input voltage waveform.
Fig. 4 illustrates the exemplary method for detecting and measure input voltage according to each side of the present invention.
Detailed description of the invention
As discussed in detail below, the embodiment of this technology plays offer voltage detecting and measuring circuit
Effect, this voltage detecting and measuring circuit are used for measuring applying to system, such as control and automatization
The input AC voltage of the parts of system.Specifically, this technology utilizes multiple Zener diode and light
Bonder produces the output waveform of the feature with instruction input voltage size.
" embodiment ", " embodiment ", " example embodiment " mentioned in description refers to be retouched
The embodiment stated can comprise a concrete feature, structure or characteristic, but is not each embodiment
This concrete feature, structure or characteristic must be comprised.Further, these terms are not necessarily referring to same reality
Execute example.Additionally, when describing concrete feature, structure or characteristic in conjunction with the embodiments, regardless of whether bright
Really explanation, all thinks that it is in this area skill that these features, structure or characteristic are attached to other embodiments
In the ken of art personnel.
Turning now to accompanying drawing, with reference first to Fig. 1, it is shown that have voltage detecting and measuring circuit 12
System, such as industrial control system 10.In the illustrated embodiment, system 10 includes AC electricity
Power input conductor 14, AC electric power input conductor 14 is configured to the AC voltage from power supply 16
It is supplied to the downstream electrical equipment such as represented by reference 18 and 20.In the illustrated embodiment,
Voltage detecting and measuring circuit 12 are configured to detect input voltage signal and distinguish input conductor 14
On multiple input voltage waveforms.
In this example embodiment, circuit 12 includes the first and second Zener diodes 22 and 24,
First and second Zener diodes 22 and 24 are operatively coupled to AC electric power input conductor 14 and quilt
It is configured to transmit the part of the input AC voltage from AC electric power input conductor 14 to produce output
Waveform.In the illustrated embodiment, the first Zener diode 22 coupled to AC electric power input conductor
14, and the second Zener diode 24 coupled to can be at earthy reference voltage line.
Additionally, photo-coupler 26 coupled to the first and second Zener diodes 22 and 24, and joined
It is set to receive the output waveform from the first and second Zener diodes 22 and 24.Additionally, circuit
12 include processing circuit 28, and it is configured to the process output waveform from photo-coupler 26 with detection
Multiple input voltage waveforms on input voltage signal and/or differentiation input conductor 14.
In this example embodiment, circuit 12 also includes filter circuit 30, its be configured to filter from
The higher order harmonics of the input AC voltage that power supply 16 receives.Additionally, this circuit includes being arranged in electricity
The resistor network 32 with multiple resistor between source 16 and photo-coupler 26.Resistor net
Network 32 is configured to limit by photo-coupler 26 and the first and second Zener diodes 22 and 24
Electric current.
In operation, process circuit 28 and be configured to detect input voltage signal and produce sampling output wave
Shape, to estimate the size of input voltage based on this sampled output waveform.In shown enforcement, logical
Cross display 34 and the size of the input voltage of estimation is shown to the user of system 10.Additionally, system
10 include control circuit 36, and control circuit 36 receives the size of the input voltage estimated and is configured
For controlling the voltage of electrical equipment 18 and 20 based on this estimated value.
In certain embodiments, process circuit 28 and be configured to network 40 by with estimated value
Input voltage measurement is sent to remotely control and/or monitoring station 38.As understood by a person skilled in the art,
Network 40 can include that the parts such as such as network cable, NIC, router and bridger come
Communicate with control circuit 36.Remotely control and/or monitoring station 38 can be additionally configured to remotely control
The input voltage of electrical equipment 18 and 20.
Fig. 2 illustrates the example arrangement of the system 10 with the voltage detecting of Fig. 1 and measuring circuit 12
50.In an illustrated embodiment, power supply 16 include being configured to exporting three-phase voltage (such as from
Electrical network) three phase mains.In an example embodiment, power supply 16 is configured to supply 110 volts
Special input voltage signal.In another example embodiment, power supply 16 is configured to supply 220 volts
Special input voltage signal.
In operation, the higher-order that filter circuit 30 filters from the input AC voltage of power supply 16 reception is humorous
Ripple.In an example embodiment, filter circuit 30 includes electromagnetic interference and harmonic filter.This
Outward, the resistor network 32 being arranged in filter circuit 30 downstream limits by the first and second Zeners two
Pole pipe 22 and 24 and the electric current of photo-coupler 26.
In this example is implemented, resistor network 32 includes reference 52,54,56 and 58 institute
Four resistors represented.Pass through however, it is possible to use greater or lesser number of resistor to limit
The electric current of the first and second Zener diodes 22 and 24.Furthermore, it is possible to reduce based on desired electric current
Select each resistance value in resistor 52,54,56 and 58.
As shown, the first Zener diode 22 coupled to AC electric power input conductor 14, and
Two Zener diodes 24 coupled to the most earthy reference voltage line.First and second Zener two poles
Pipe 22 and 24 be configured to transmission input AC voltage more than the first and second Zener diodes 22
With the part of each breakdown voltage of 24, to produce output waveform.
In this example embodiment, regulate in the first and second Zener diodes 22 and 24 is each
Breakdown voltage is to distinguish multiple input voltages.In certain embodiments, the first and second Zener diode
22 and 24 are additionally configured to each breakdown potential based on the first and second Zener diodes 22 and 24
Pressure carrys out filtered voltage noise.
In the illustrated embodiment, photo-coupler 26 is configured to receive the first and second Zener two poles
The output waveform of pipe 22 and 24.In this example embodiment, photo-coupler 26 includes bi-directional digital
Photo-coupler.Photo-coupler 26 includes the light emitting diode such as represented by reference 60 and is joined
It is set to based on the output waveform detection input voltage received from the first and second Zener diodes 22 and 24
The photoelectric detector 62 of existence.
Process circuit 28 to be configured to process the output waveform from photo-coupler, to estimate to be detected
The size of input voltage.In the illustrated embodiment, process circuit 28 to include being configured to storage
Memorizer 64 from the output waveform of photo-coupler 26.Additionally, process circuit 28 also include by
It is configured to estimate the processor 66 of the size of input voltage.
Memorizer 64 can include hard disk drive, CD drive, tape drive, deposit at random
Access to memory (RAM), read only memory (ROM), programmable read only memory (PROM),
Redundant array of independent disks (RAID), flash memory, magneto-optic memory, holographic memory, magnetic bubble
Memorizer, magnet drum, memory stick, Mai LaBand, intelligence dish, thin-film memory, Zip drive,
Etc..
It should be noted that the concrete process that the invention is not restricted to any process task for performing the present invention
Device.Term " processor " is intended to indicate that the required by task being able to carry out the present invention is wanted as used herein
Computing or any machine of calculating.Term " processor " is intended to indicate that and any can accept structure
That changes inputs and can process this input to produce the machine of output according to specified rule.
It should also be noted that as skilled in the art will understand, phrase used herein " is configured
For " refer to the processor combination equipped with the hardware and software of the task for performing the present invention.
In an example embodiment, processor 66 is configured to produce sampled output waveform and base
The size of input voltage is estimated in sampled output waveform.In the exemplary embodiment, based on output waveform
The root-mean-square value of amplitude estimate the size of input voltage.In an example embodiment, circuit
12 include analog-digital converter 68, and it coupled to process circuit 28 with the output wave by photo-coupler 26
Shape signal digitized.In certain embodiments, analog-digital converter 68 is integrated in the process of circuit 12
In circuit 28.
As it was previously stated, by control circuit 36 utilize the input voltage size of estimation to configure industry and from
One or more electrical equipment 18 and 20 (such as, fan) used in dynamic networked control systems.
Advantageously, detection and the measurement of input voltage promotes the input voltage to such as equipment 18 and 20
Control in real time.
Fig. 3 illustrates with the corresponding output voltage produced by voltage detecting and the measuring circuit 12 of Fig. 1
The example input voltage waveform 90 of waveform 92.In the illustrated embodiment, reference 94 and 96
Represent corresponding to 110 volts and the waveform of the input signal of 220 volts.Additionally, reference 98
Represent with 100 be supplied to photo-coupler 26 from the first and second Zener diodes 22 and 24
Corresponding output waveform.
It can be seen that output waveform 98 and 100 include input voltage waveform passed through the first He
The part of the second Zener diode 22 and 24.In the illustrated embodiment, selection first and second is neat
Receive each breakdown voltage of diode 22 to distinguish multiple input voltage waveform respectively, such as 110
Volt and the input voltage signal of 220 volts.
In the illustrated embodiment, reference 102 and 104 represents by the process circuit 28 of Fig. 1
The sampled output waveform produced.Reference 102 represents adopting of the input voltage corresponding to 110 volts
Sample waveform.Additionally, reference 104 represents the sample waveform of the input voltage corresponding to 220 volts.
Can use and process circuit 28 to revise the output waveform 102 and 104 of sampling to produce the ripple rebuild
Shape 106 and 108.It can be seen that the feature instruction input waveform 94 of output waveform 106 and 108
With 96 size, consequently facilitating the in real time detection of input voltage and measuring.
Fig. 4 illustrates the exemplary method for detecting and measure input voltage according to each side of the present invention
120.At frame 122, input AC voltage is applied to system.Then input AC voltage is by electricity
Resistance device network is to limit the electric current (frame 124) by components downstream.At frame 126, will input AC electricity
Pressure applies the multiple Zener diodes (frame 124) to voltage detecting and measuring circuit.
The part of the breakdown voltage exceeding Zener diode of input AC voltage passes through Zener diode,
To produce output waveform (frame 126 and 128).At frame 130, output waveform is supplied to photo-coupler.
In this example embodiment, the feature of output waveform depends on the size of input voltage.
Additionally, process the output of photo-coupler with detection input voltage and the size of estimation input voltage
(frame 132).At frame 134, the size of input voltage is shown to the user of system.Additionally, based on
The size of the input voltage estimated controls the voltage (frame 136) of at least one electrical equipment.
The various aspects of construction described above may be used for detection and measurement applies the input to system
AC voltage.Specifically, technology described above provide isolation output signal, its with indicate into
The feature of the input AC signal entered.Advantageously, by while providing low-voltage noise suppressed
The breakdown voltage value of regulation Zener diode, Zener diode is used for voltage detecting and measurement be easy to right
The detection of different voltage levvls.
This technology can be utilized in the system of such as industrial control system, with detection enter voltage and
Automatically configure the voltage of the parts of the fan of such as these systems, thus eliminate configuring these parts
The needs of manpower intervention.
Although the most only illustrate and describing some feature of the present invention, those skilled in the art can think
To many modifications and variations.It will therefore be appreciated that claims are intended to covering falls into this
The bright all such modifications and variations in true spirit.
Claims (16)
1. voltage detecting and a measuring circuit, including:
First Zener diode, it is configured to be operatively coupled to AC power input line；
Second Zener diode, it is configured to be operatively coupled to reference voltage line, wherein, described
One and second Zener diode be configured to transmit from described AC power input line input AC electricity
The part of pressure is to produce output waveform；
Photo-coupler, it coupled to described first and second Zener diodes to receive from described first
With the described output waveform of the second Zener diode, to detect described input AC voltage；
Processing circuit, it is configured to receive the described output waveform from described photo-coupler, and
Existence and/or the size of described input AC voltage is determined based on described output waveform；And
Control circuit, it is configured to size based on described input AC voltage and controls at least one
The voltage of electrical equipment,
Wherein, each breakdown voltage of described first and second Zener diodes be adjusted to distinguish many
Individual described input AC voltage.
Voltage detecting the most according to claim 1 and measuring circuit, also include resistor network,
Described resistor network is configured to limit by described photo-coupler and described first and second Zeners
The electric current of diode.
Voltage detecting the most according to claim 1 and measuring circuit, wherein, described benchmark electricity
Line ball includes earth potential.
Voltage detecting the most according to claim 1 and measuring circuit, wherein, described process electricity
Road is configured to produce sampled output waveform and estimate based on described sampled output waveform described defeated
Enter the size of AC voltage.
Voltage detecting the most according to claim 4 and measuring circuit, wherein, based on described defeated
Go out the root-mean-square value of amplitude of waveform to estimate the size of described input AC voltage.
Voltage detecting the most according to claim 1 and measuring circuit, wherein, described first He
Second Zener diode is configured to each puncturing based on described first and second Zener diodes
Voltage carrys out filtered voltage noise.
Voltage detecting the most according to claim 1 and measuring circuit, also include analog-digital converter,
Described analog-digital converter coupled to described process circuit, and is configured to from described photo-coupler
Output waveform signals digitized.
Voltage detecting the most according to claim 1 and measuring circuit, wherein, described optical coupling
Device includes that light emitting diode and photoelectric detector, described photoelectric detector are configured to based on from described
The described output waveform of the first and second Zener diodes detects the existence of described input AC voltage.
9., for detection and a method for measurement input AC voltage, described method includes:
Input AC voltage is applied to multiple Zener diodes；
Transmit described input AC voltage the breakdown voltage exceeding described Zener diode part with
Output waveform is supplied to photo-coupler, and wherein, the feature of described output waveform depends on described input
The size of AC voltage；
Process the output of described photo-coupler to detect described input AC voltage and to estimate described defeated
Enter the size of AC voltage；
Size based on estimated described input AC voltage controls at least one electrical equipment；With
And
Regulate the described breakdown voltage of described Zener diode to distinguish multiple input AC voltages.
Method the most according to claim 9, wherein, processes described output waveform and includes sampling
Described output waveform, and measure the amplitude of the waveform sampled to estimate described input AC voltage
Size.
11. 1 kinds of voltage detecting and measuring circuit, including:
AC electric power input conductor；
First and second Zener diodes, it coupled to described AC electric power input conductor, and is joined
It is set to transmit the part of the input AC voltage from described AC electric power input conductor to produce output wave
Shape；
Photo-coupler, it coupled to described first and second Zener diodes, and described photo-coupler is joined
It is set to receive the described output waveform from described first and second Zener diodes；
Multiple resistors, its be disposed in described AC electric power input conductor and described photo-coupler it
Between, described resistor is configured to limit by described photo-coupler and described first and second Zeners two
The electric current of pole pipe；
Processing circuit, it is configured to the process output waveform from described photo-coupler to detect input
Voltage signal and/or distinguish the multiple input voltage waveforms on described AC electric power input conductor；And
Control circuit, it is configured to size based on described input AC voltage and controls at least one
The voltage of electrical equipment,
Wherein, each breakdown voltage of described first and second Zener diodes is adjusted to distinguish institute
State multiple input voltage waveform.
12. voltage detecting according to claim 11 and measuring circuits, wherein, the plurality of
Input voltage waveform includes 110 volt signal or 220 volt signal.
13. voltage detecting according to claim 11 and measuring circuits, wherein, described first
It is configured to each institute based on described first and second Zener diodes with the second Zener diode
State breakdown voltage to filter low-voltage noise.
14. voltage detecting according to claim 11 and measuring circuits, also include filtering circuit,
To filter the noise from input AC voltage.
15. voltage detecting according to claim 11 and measuring circuits, wherein, described optocoupler
Clutch is configured to produce sampled output waveform, and described process circuit is configured with described sampling
Output waveform estimates the size of described input AC voltage.
16. voltage detecting according to claim 11 and measuring circuits, wherein, described optocoupler
Clutch includes bi-directional digital photo-coupler.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US12/787,188 US8674681B2 (en) | 2010-05-25 | 2010-05-25 | Voltage detection and measurement circuit |
| US12/787,188 | 2010-05-25 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102262178A CN102262178A (en) | 2011-11-30 |
| CN102262178B true CN102262178B (en) | 2016-12-14 |
Family
ID=
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|---|---|---|---|---|
| US4712153A (en) * | 1984-09-03 | 1987-12-08 | Charbonnages De France | Power circuit and trigger device comprising same |
| US4816960A (en) * | 1984-11-13 | 1989-03-28 | Westinghouse Brake & Signal Co., Ltd. | Fail-safe output switching device |
| CN2177270Y (en) * | 1993-06-30 | 1994-09-14 | 首钢总公司 | Fault guide safety input interface device |
| CN1182393A (en) * | 1995-04-19 | 1998-05-20 | Gec阿尔斯托姆Acec运输公司 | AC input cell for data acquisition circuit |
| CN2377540Y (en) * | 1999-06-08 | 2000-05-10 | 陆永安 | Automotive electrical system test pencil |
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4712153A (en) * | 1984-09-03 | 1987-12-08 | Charbonnages De France | Power circuit and trigger device comprising same |
| US4816960A (en) * | 1984-11-13 | 1989-03-28 | Westinghouse Brake & Signal Co., Ltd. | Fail-safe output switching device |
| CN2177270Y (en) * | 1993-06-30 | 1994-09-14 | 首钢总公司 | Fault guide safety input interface device |
| CN1182393A (en) * | 1995-04-19 | 1998-05-20 | Gec阿尔斯托姆Acec运输公司 | AC input cell for data acquisition circuit |
| CN2377540Y (en) * | 1999-06-08 | 2000-05-10 | 陆永安 | Automotive electrical system test pencil |
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Address after: ohio Patentee after: Rockwell automation technologies Address before: ohio Patentee before: Rockwell Automation Tech Inc. |