CN106569025A - Device of measuring power consumption, device and method of measuring power supply status in non-contact manner - Google Patents
Device of measuring power consumption, device and method of measuring power supply status in non-contact manner Download PDFInfo
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- CN106569025A CN106569025A CN201510643879.6A CN201510643879A CN106569025A CN 106569025 A CN106569025 A CN 106569025A CN 201510643879 A CN201510643879 A CN 201510643879A CN 106569025 A CN106569025 A CN 106569025A
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Abstract
The present invention relates to a device of measuring the power consumption, and a device and method of measuring the power supply status in a non-contact manner. The device of measuring the power consumption is used to measure the active power transmitted by power supply lines and comprises a detection unit and a calculation unit, the calculation unit obtains a power factor and an active power value according to an induction voltage signal and an induction current signal which are generated by the detection unit, and the detection unit comprises an electric field detector and a magnetic field detector. The two electrodes of the electric field detector are arranged nearby the power supply lines separately, the induction voltage signal is the potential difference between the two electrodes, and the two coils of the magnetic field detector are equipped with the iron cores separately and are arranged nearby the power supply lines. The winding directions of the two coils are reverse, and the two coils are in series coupling according to the same induction current directions, thereby obtaining the induction current signal.
Description
Technical field
The present invention relates to a kind of device, the dress of non-contact measurement power supply situation of measurement power consumption
Put and method, more particularly to one kind in a non-contact manner, senses the voltage on Alternating Current Power Supply line
With electric current, and then the device and method of power consumption is measured.
Background technology
Traditional Domestic electric meter, it is adaptable to civil power it is accumulative, it is generally direct by electrical lead
Measurement electric current and voltage swing, to measure electric power.In fact, it is that foundation has that electricity consumption is calculated
Work(power (real power or active power) as calculate benchmark, for representing power consumption
The active power of amount is relevant with power factor (power factor).For resistive load,
Power factor is 1.And for non-resistive load, such as inductive, capacity load, to it
Power factor during power supply is not 1.Wire type measurement can obtain actual current, virtual voltage,
With power factor.But contact type measurement has the impedance loss of measurement, also there is the potential danger of electric leakage
Danger, therefore design complex, and install loaded down with trivial details.
In addition, electric current hook table is the electric current on non-contact measurement supply lines.Compared to contact
Measurement, it has the characteristic of simplicity, and can avoid contact with the danger of electric leakage.However, using non-
The electric current hook table of contact type measurement, only energy is to real-time current, it is impossible to while obtaining real-time voltage
Also power factor cannot be obtained, also because power factor can not be obtained, therefore cannot be had
The value of work(power.In other words, in the case where power factor is not 1, using contactless
The electric current hook table of measurement, it is impossible to obtain active power.
The content of the invention
The technical problem to be solved is to provide a kind of for the deficiencies in the prior art
Device, the device and method of non-contact measurement power supply situation of measurement power consumption, it passes through to survey
The electric field of amount supply lines is obtained obtaining the voltage of supply lines by measuring the magnetic field of supply lines
The electric current of supply lines, and the power factor of alternating current is obtained, active power is obtained whereby.
The technical problem to be solved is achieved by the following technical solution：
The embodiment of the present invention provides a kind of device of measurement power consumption, for measuring single-phase three-wire
Active power that first live wire (L1) and the second live wire (L2) of 220V supply lines is transmitted or
In single-phase-two-wire 110V supply lines by live wire (L) and the neutral conductor (N) transmitted it is active
Power.The device of measurement power consumption includes detecting unit and computing unit, and computing unit electrically connects
Detecting unit is connect, induced voltage signal and induced-current that computing unit is produced according to detecting unit
Both signal of change phase difference obtains power factor, and according to induced voltage signal, induced-current
Signal obtains active power value with power factor.The device of measurement power consumption is characterised by：Detect
Survey unit and there is electric field detector and magnetic field detector, detecting unit is arranged adjacently to into the first confession
Electric wire and the second supply lines, wherein electric field detector have first electrode and second electrode, magnetic field
Detector has the first coil and the second coil of magnetic conductive component of arranging in pairs or groups respectively.First electrode and the
Two electrodes are respectively provided with and are adjacent to the first supply lines and the first supply lines, and first electrode is supplied with first
Electric wire causes on the first electrode the first current potential according to capacity effect, and second electrode is supplied with second
Electric wire causes on the second electrode the second current potential according to capacity effect, and induced voltage signal is the
The potential difference of one current potential and the second current potential.First coil and the second coil are respectively provided with and are adjacent to the
The direction of winding of one supply lines and the second supply lines, first coil and the second coil is conversely, first
Coil and the second coil coupled in series according to identical inductive current direction, to obtain corresponding to the
The sensor current signal of the electric current of one supply lines and the second supply lines, this direction of winding is contrary and goes here and there
The mode of connection coupling can be effective against earth magnetism, substantially reduce the difference of earth magnetism in different occasions and
Affect measurement result.
The embodiment of the present invention provides a kind of method of measurement power consumption, supplies by first for measuring
The active power that electric wire and the second supply lines are transmitted, the method is comprised the following steps, first,
First electrode and second electrode are respectively provided with and are adjacent to the first supply lines and the second supply lines, and
First coil and the second coil are respectively provided with and are adjacent to the first supply lines and the second supply lines, its
Middle first coil is contrary with the direction of winding of the second coil.Then, the current potential of first electrode is obtained
Induced voltage signal is produced with the potential difference of the current potential of second electrode.Then, by first coil
With the second coil according to identical inductive current direction coupled in series, with obtain corresponding to first supply
The sensor current signal of the electric current of electric wire and the second supply lines.Come again, according to induced voltage signal
Phase difference between sensor current signal to obtain power factor, and using computing unit foundation
Induced voltage signal, sensor current signal and power factor are calculated and obtain active power.
The embodiment of the present invention provides a kind of contactless power supply situation arrangement for detecting, for simultaneously
The induced voltage signal and sensor current signal of measurement supply lines, supply lines has further included first
Supply lines and the second supply lines, power supply situation arrangement for detecting is arranged at and keeps non-connecing with supply lines
The position of tactile specific range, and with electric field detector and magnetic field detector；Electric field detector
Respectively the first supply lines and the are arranged adjacently to specific range with first electrode and second electrode
Two supply lines, first electrode is caused on the first electrode with the first supply lines according to capacity effect
First current potential, second electrode is caused on the second electrode with the second supply lines according to capacity effect
The potential difference of the second current potential, the first current potential and the second current potential is induced voltage signal；Wherein,
There is magnetic field detector first coil to be positioned adjacent to first with specific range respectively with the second coil
The direction of winding of supply lines and the second supply lines, first coil and the second coil is conversely, First Line
Circle with the second coil according to identical inductive current direction coupled in series, with acquisition corresponding to first
The sensor current signal of supply lines and the second supply lines.
The embodiment of the present invention provides a kind of device of non-contact measurement supply current, for measuring
The magnitude of current that supply lines is transmitted, supply lines has further included the first supply lines and the second supply lines,
And the device for measuring supply current includes detecting unit, detecting unit has magnetic field detector, its
In, magnetic field detector has first coil and the second coil；And first coil and the second coil point
Be not arranged adjacently to the first supply lines and the second supply lines, and first coil and the second coil around
Line is in opposite direction, first coil and the second coil coupled in series according to identical inductive current direction,
To obtain corresponding to the first supply lines and the sensor current signal of the electric current of the second supply lines.
In other words, the present invention provides a kind of device of measurement power consumption, for measuring supply lines
The active power transmitted, the supply lines has further included the first supply lines and the second supply lines,
And the device of the measurement power consumption includes a detecting unit and a computing unit, the computing unit electricity
Property connect the detecting unit, the induced voltage letter that the computing unit is produced according to the detecting unit
Number a power factor is obtained with a sensor current signal, and according to the induced voltage signal, the sense
Induced current signal obtains the active power with the power factor, and there is the detecting unit electric field to detect
Device and a magnetic field detector are surveyed, for being arranged adjacently to first supply lines and second supply lines,
Wherein the electric field detector has a first electrode and a second electrode, and the magnetic field detector has
One first coil and one second coil；Wherein, the first electrode is respectively provided with the second electrode
Be adjacent to first supply lines and second supply lines, the first electrode and first supply lines according to
Cause in the first electrode one first current potential according to capacity effect, the second electrode with this second
Supply lines causes one second current potential according to capacity effect in the second electrode, the induced voltage
Signal is the potential difference of first current potential and second current potential；Wherein, the first coil with this
Two coil is respectively provided with and is adjacent to first supply lines and second supply lines, the first coil with
The direction of winding of second coil conversely, the first coil with second coil according to identical sensing
The sense of current and coupled in series, to obtain corresponding to first supply lines and second supply lines
The sensor current signal of electric current.
The cosine value of the phase difference between the induced voltage signal and the sensor current signal is work(
Rate factor, the active power corresponds to the induced voltage signal, the sensor current signal and the work(
The product of rate factor.
The magnetic field detector further includes one first magnetic conductance element and one second magnetic conductance element, and this first
Coil is set around the first magnetic conductance element, and second coil is set around the second magnetic conductance element.
The first coil be used for sensing one first magnetic field produced by the electric current of first supply lines and
One first inductive current direction is obtained, second coil is used for sensing the electric current of second supply lines
Produced one second magnetic field and obtain one second inductive current direction, wherein first magnetic field
In the direction opposite the direction in second magnetic field, first inductive current direction and second induced electricity
Stream direction is identical.
The computing unit by the induced voltage signal, the sensor current signal in comparison with a look-up table,
To be corrected to the active power value.
The present invention also provides a kind of method of measurement power consumption, for measuring the first confession of supply lines
The active power that electric wire and one second supply lines are transmitted, the method includes：It is electric by one first
Pole is respectively provided with a second electrode and is adjacent to first supply lines and second supply lines, and will
One first coil is respectively provided with one second coil and is adjacent to first supply lines with second power supply
Line, the wherein first coil are contrary with the direction of winding of second coil；Obtain the first electrode
Current potential and the second electrode current potential potential difference and produce an induced voltage signal；By this
One coil and second coil coupled in series according to identical inductive current direction, to obtain correspondence
In first supply lines and a sensor current signal of the electric current of second supply lines；And foundation
Phase difference between the induced voltage signal and the sensor current signal to obtain a power factor,
And using a computing unit according to the induced voltage signal, the sensor current signal and the power because
Number is calculated and obtains the active power.
In the step of obtaining the active power, the induced voltage signal and the sensor current signal
Between phase difference cosine value be power factor, the computing unit by the induced voltage signal,
The sensor current signal is multiplied to obtain the active power with the power factor.
The method of the measurement power consumption is further included：The computing unit by the induced voltage signal, should
Sensor current signal in comparison with a look-up table, to be corrected to the active power value.
It is adjacent to first supply lines and is somebody's turn to do the first coil and second coil is respectively provided with
In the step of second supply lines, the first coil is used for sensing the electric current of first supply lines and is produced
Raw one first magnetic field and obtain one first inductive current direction, second coil is used for sensing this
One second magnetic field produced by the electric current of the second supply lines and obtain one second inductive current direction,
The wherein direction in the direction opposite second magnetic field in first magnetic field, the first induced-current side
To identical with second inductive current direction.
It is adjacent to first supply lines and is somebody's turn to do the first coil and second coil is respectively provided with
Further including in the step of second supply lines makes the first coil be set around one first magnetic conductance element, makes
Second coil is set around one second magnetic conductance element.
The present invention also provides a kind of contactless power supply situation arrangement for detecting, for measuring simultaneously
The induced voltage signal and sensor current signal of supply lines, the supply lines has further included one first
Supply lines and one second supply lines, the power supply situation arrangement for detecting is arranged to be protected with the supply lines
The position of a non-contacting specific range is held, and with an electric field detector and a magnetic field detector；
There is the electric field detector first electrode to arrange adjacent with the specific range respectively with a second electrode
It is bordering on first supply lines and second supply lines, the first electrode and the first supply lines foundation
Capacity effect and one first current potential is caused in the first electrode, the second electrode with this second supply
Electric wire according to capacity effect and one second current potential is caused in the second electrode, first current potential with
The potential difference of second current potential is the induced voltage signal；Wherein, the magnetic field detector has
One first coil is positioned adjacent to first supply lines with the specific range respectively with one second coil
With second supply lines, the direction of winding of the first coil and second coil conversely, this first
Coil and second coil coupled in series according to identical inductive current direction, with obtain corresponding to
The sensor current signal of first supply lines and second supply lines.
The first coil is set around one first magnetic conductance element, and second coil is set around one second magnetic
Guiding element.
The specific range is to measure the supply lines to the contactless power supply situation arrangement for detecting
Beeline, the beeline is more than 15 millimeters.
The present invention also provides a kind of device of non-contact measurement supply current, for measuring power supply
The magnitude of current that line is transmitted, the supply lines has further included the first supply lines and the second supply lines,
And the device of the measurement supply current includes a detecting unit, there is the detecting unit magnetic field to detect
Device is surveyed, wherein, the magnetic field detector has a first coil and one second coil；And this first
Coil is respectively provided with second coil and is adjacent to first supply lines and second supply lines, and
The direction of winding of the first coil and second coil is conversely, the first coil and second coil
The coupled in series according to identical inductive current direction, to obtain corresponding to first supply lines and be somebody's turn to do
One sensor current signal of the electric current of the second supply lines.
The first coil is set around one first magnetic conductance element, and second coil is set around one second magnetic
Guiding element.
In sum, the embodiment of the present invention provides a kind of device, contactless of measurement power consumption
The device and method of measurement power supply situation, is sensed using two electrodes according to the principle of capacity effect
Voltage change on supply lines, and using the curent change on two coil-induced supply lines,
After obtaining the electric current and voltage change of supply lines, compare the phase place of electric current and both voltage changes
Difference is obtained power factor, therefore can obtain active power.Based on this contactless measurement,
Device and method of this measurement power consumption does not have the impedance loss of wire type measurement and complicated and can
The operation sequence that can be caused danger, is also not in contact with the potential danger leaked electricity.
For enable be further understood that the present invention feature and technology contents, refer to below in connection with
Detailed description of the invention and accompanying drawing, but this explanation is only used for illustrating the present invention with appended accompanying drawing,
Rather than make any restriction to protection scope of the present invention.
Description of the drawings
Fig. 1 is the functional block diagram of the device of measurement power consumption provided in an embodiment of the present invention；
Fig. 2 is the survey of the electric field detector of the device of measurement power consumption provided in an embodiment of the present invention
The schematic diagram of the electric field of amount supply lines；
Fig. 3 is the magnetic field detector measurement of the device of measurement power consumption provided in an embodiment of the present invention
The circuit diagram in the magnetic field of supply lines；
Fig. 4 is the power consumption of the measurement device supply lines of measurement power consumption provided in an embodiment of the present invention
The configuration diagram of amount；
Fig. 5 is the flow chart of the method for the measurement power consumption that present example is provided；
Fig. 6 is the oscillogram of the voltage of traditional single-phase three-wire supply lines；
Fig. 7 is the schematic diagram that the single-phase three-wire that another embodiment of the present invention is provided supplies electricity to load；
Fig. 8 is the electric field detector of the device of the measurement power consumption that another embodiment of the present invention is provided
Measurement supply lines electric field schematic diagram；
Fig. 9 is the magnetic field detector of the device of the measurement power consumption that another embodiment of the present invention is provided
The circuit diagram in the magnetic field of measurement supply lines.
【Description of reference numerals】
1：The device of measurement power consumption
11：Electric field detector
12：Magnetic field detector
111：First electrode
112：Second electrode
113：Voltage signal provides unit
2：Computing unit
3：Supply lines
SV：Induced voltage signal
SI：Sensor current signal
EF：Electric field
MF：Magnetic field
V1：First current potential
V2：Second current potential
31：First supply lines
32：Second supply lines
+、-：Polarity
4、4’：Power supply
5、6：Load
121：First coil
122：Second coil
123：Current signal provides unit
M1：First magnetic field
M2：Second magnetic field
D1：First inductive current direction
D2：Second inductive current direction
I：Electric current
13：Module
121M：First magnetic conductance element
122M：Second magnetic conductance element
S110、S120、S130、S140：Steps flow chart
L1：First live wire
L2：Second live wire
G：Ground connection
D：Specific range
Specific embodiment
Embodiment one
The present embodiment is device of the device with non-contact measurement power supply situation for measuring power consumption
Embodiment.
Fig. 1 is refer to, Fig. 1 is the work(of the device of measurement power consumption provided in an embodiment of the present invention
Can block diagram.The device of the measurement power consumption of the present embodiment is used for being supplied using non-contact mode measuring
The active power that electric wire 3 is transmitted, the supply lines 3 at least includes the first supply lines and second
Supply lines.In the present embodiment, the first supply lines and the second supply lines are that single-phase-two-wire 110V is supplied
Live wire (L) and the neutral conductor (N) in wire gauge, but the present invention not therefore restriction.
The device of measurement power consumption includes detecting unit 1 and computing unit 2, and computing unit 2 is electric
Property connection detecting unit 1, the induced voltage signal that computing unit 2 is produced according to detecting unit 2
SV and sensor current signal SI acquisitions power factor (PF), and foundation induced voltage signal SV,
Sensor current signal SI obtains active power value with power factor (PF).The dress of measurement power consumption
Put and be characterised by：Detecting unit 1 has electric field detector 11 and magnetic field detector 12, is used for
It is arranged adjacently to the live wire and the neutral conductor of supply lines 3.Electric field detector 11 is detectd by contactless
The electric field EF of supply lines is surveyed, and induced voltage signal SV is produced according to electric field EF, and will sensing
Voltage signal SV is sent to computing unit 2.Magnetic field detector 12 is powered by noncontact detecting
The magnetic field MF of line, and sensor current signal SI is produced according to magnetic field MF, and induced-current is believed
Number SI is sent to computing unit 2.Computing unit 2 can provide computing induced voltage signal SV with sense
Induced current signal SI, and storage correspondence parameter or look-up table (Look-Up Table, LUT)
Function.The e.g. microprocessor (MCU) of computing unit 2, but the present invention not therefore restriction.
In one embodiment, detecting unit 1 can be produced simulation by computing unit 2 using sampling mechanism
The induced voltage signal SV and sensor current signal SI of matter is converted to digital signal to carry out numeral
Calculate and record, but therefore the present invention does not also limit.Detect with regard to electric field detector 11 and magnetic field
Survey device 12 and refer to the follow-up explanation corresponding to Fig. 2 and Fig. 3.
Then, Fig. 2 is refer to, Fig. 2 is the dress of measurement power consumption provided in an embodiment of the present invention
The schematic diagram of the electric field of the measurement supply lines of the electric field detector put.In fig. 2, supply lines with
First supply lines 31 is represented with the section of the second supply lines 32.Electric field detector is electric with first
Pole 111 and second electrode 112, the supply lines 31 (e.g. live wire) of first electrode 111 and first
According to capacity effect and the first current potential V1 is caused in first electrode 111, second electrode 112 with
Second supply lines 32 (the e.g. neutral conductor) is made according to capacity effect in second electrode 112
Into the second current potential V2.Induced voltage signal SV in fig. 2 represents the first current potential V1 and
The potential difference (V1-V2) of two current potential V2.Voltage signal provides unit 113 and obtains the first current potential
The potential difference (V1-V2) of V1 and the second current potential V2 and produce induced voltage signal SV.Voltage
Signal provides unit 113 for example, at least includes potentiometer.But in practical application, in order to feel
Voltage signal SV is answered to be supplied to the computing unit 2 of Fig. 1, voltage signal to provide unit 113 and more may be used
Induced voltage signal SV is converted to and is suitable to the signal that computing unit 2 is received, the present invention is not limited
Determine the implementation of induced voltage signal SV.
Then, in the present embodiment, the first supply lines 31 can also be the neutral conductor (N), correspondence
The second supply lines 32 of ground is then live wire (L), the first supply lines 31 and the whichever of the second supply lines 32
Be live wire (L) whichever be operation that the neutral conductor (N) has no effect on electric field detector, Yi Ji
The electric field induction principle of one electrode 111 and second electrode 112.That is, the of the present embodiment
Relation of one electrode 111 with second electrode 112 relative to two power lines can be exchanged, simply electricity
Pressure signal provide the potential difference measured by unit 113 polarity (as shown in Figure 2+polarity with
- polarity) may be contrary.However, the principle based on alternating current, can learn the first supply lines 31
Can periodically change with the potential difference (V1-V2) of the second supply lines 32, and potential difference (V1-V2)
Polarity also can alternate change.Therefore, in practical application, the polarity of potential difference (V1-V2)
It is also periodic alternate change with the time.Typically, the voltage of supply lines is the time
Function, such as Vm*sin (ω t+ θ 1), Vm is the maximum of voltage, is the frequency of ω alternating currents
Rate, θ 1 is voltage-phase, and t is the time.And the first current potential V1 is in response to the second current potential V2
In alternating current voltage Vm*sin (ω t+ θ 1) in the first supply lines 31 and the second supply lines 32
On the current potential set up, therefore, the phase place of potential difference (V1-V2) should be able to correspond to voltage
Phase theta 1.
Then, Fig. 3 is refer to, Fig. 3 is the dress of measurement power consumption provided in an embodiment of the present invention
The circuit diagram in the magnetic field of the magnetic field detector measurement supply lines put.Power supply 4 utilizes the first supply lines
31 and the delivering power of the second supply lines 32 to load 5.Magnetic field detector has first coil 121
With the second coil 122, the coil 122 of first coil 121 and second is respectively provided with and is adjacent to the first confession
Electric wire 31 (such as live wire (L)) and the second supply lines (such as neutral conductor (N)) 32, first
The direction of winding of the coil 122 of coil 121 and second is conversely, the coil of first coil 121 and second
122 according to identical inductive current direction coupled in series, to obtain corresponding to live wire and the neutral conductor
The sensor current signal SI of electric current.In the present embodiment, sensor current signal SI is in figure 3
First coil 121 with first coil 122 affected by the changes of magnetic field of supply lines 31,32 and
The induced-current of generation.
Specifically, in the example in figure 3, if first coil 121 is with coiling clockwise,
Second coil 122 so can be caused in the case of same magnetic direction with anti-clockwise windings,
First coil 121 is contrary with the inductive current direction of the second coil 122.First coil 121 is used
To sense the first magnetic field M1 produced by the electric current I of the first supply lines 31 (such as live wire (L))
And obtain the first inductive current direction D1.First coil 121 is used for sensing the second supply lines 32
The second magnetic field M2 produced by the electric current I of (such as the neutral conductor (N)) and obtain the second induced electricity
Stream direction D2, wherein the direction in the direction opposite the second magnetic field M2 of the first magnetic field M1, the
One inductive current direction D1 is identical with the second inductive current direction D2.Briefly, based on
The situation in opposite direction of the electric current I of the sense of current of one supply lines 31 and the second supply lines 32,
First inductive current direction D1 of first coil 121 and the second induced-current of the second coil 122
Direction D2 is identical.That is, using first coil 121 with the second coil 122 according to identical
Inductive current direction (D1 and D2) and the mode of coupled in series, can obtain corresponding to live wire simultaneously
With the sensor current signal SI of the electric current I of the neutral conductor.
In addition, in figure 3, magnetic field detector is except first coil 121, the second coil 122
Outside further include current signal provide unit 123.Current signal provides unit 123 and is used for according to stream
Cross the electric current of the coil 122 of first coil 121 and second and produce sensor current signal SI.Electric current
It is, for example, galvanometer that signal provides unit 123.Current signal provides unit 123 and is used for sensing
Current signal SI is converted into being applied to the signal for allowing the computing unit 2 of Fig. 1 to receive.However, this
Invention not current limit signal provide unit 123 implementation.
In addition, when the phase place for considering sensor current signal SI, the coil of first coil 121 and second
122 faradic phase place should be able to be corresponding on the first supply lines 31 and the second supply lines 32
The phase place (here ignores hesitation) of contained electric current I.For example, electric current I is expressed as Im*sin
(ω t+ θ 2), Im is the maximum of electric current, is the frequency of ω alternating currents, and θ 2 is current phase,
T is the time.Therefore, the faradic phase place of the coil 122 of first coil 121 and second should
Can be corresponding to the phase theta 2 of electric current I.
Further, because the direction of winding of the coil 122 of first coil 121 and second conversely,
So that under same magnetic field environment, the sense that the coil 122 of first coil 121 and second is excited
Induced current is in opposite direction and mutually offsets.For example, in the presence of earth magnetism or external magnetic field are disturbed,
In such a manner the coil 122 of first coil 121 and second of coupled in series can resist environment or
Impact or interference of the outside magnetic field to detecting result.Therefore, the first coil 121 of the present embodiment
More accurately measurement result can be obtained with the design of the second coil 122.
Then, with regard to power factor, when it is not pure resistive loads to load 5, the phase of voltage
Position θ 1 can be different from the phase theta 2 of electric current.Accordingly, when the phase of the induced voltage signal SV for obtaining
Position and the phase place of sensor current signal SI, then can obtain the voltage of supply lines and the phase difference of electric current,
Power factor is obtained accordingly.Briefly, induced voltage signal SV and sensor current signal SI
Between phase difference (can be considered the difference of phase theta 1 and phase theta 2) cosine value (Cos
(θ 1- θ 2)) it is power factor (PF), and active power is corresponding to induced voltage signal SV, sense
The product of induced current signal SI and power factor (PF).Although induced voltage signal SV, sense
Induced current signal SI is the signal of sensing, exhausted with current signal size with the voltage on supply lines
It is different to value, but the actual value of active power is compared to induced voltage signal SV, induced electricity
Stream signal SI is a proportionality constant with the difference of the product of power factor (PF), accordingly only
Correction program must be passed through can then be readily obtained the actual value of active power.Surveyed using this every time
Only need to be corrected once before the device of amount power consumption.Even, as long as this measures power consumption
Relative position of the device relative to supply lines 3 (including the first supply lines 31 and the second supply lines 32)
Put and do not change, then correct power consumption can be kept to detect.
In practice, computing unit 2 can be utilized induced voltage signal SV, sensor current signal
SI in comparison with a look-up table (Look-up Table, LUT), to be corrected to active power value.
When correction program is done, the device of this measurement power consumption must be positioned according to aforesaid mode first
In the adjacent place of power line, the contact line power measuring apparatus then with unification standard are entered
Row measurement, then by the present embodiment measurement power consumption device obtained by active power numerical value
Relatively, to obtain the correlation-corrected parameter such as scale parameter, and can be big in various different capacities
Measure in the case of little, and set up look-up table, so that the device of measurement power consumption is normal
Can coordinate simple calculating via the look-up table that this is determined in advance during work and accurately be had
Work(magnitude of power.
Then Fig. 4 is refer to, Fig. 4 is the device of measurement power consumption provided in an embodiment of the present invention
The configuration diagram of the power consumption of measurement supply lines.First supply lines 31 of two-wire supply lines 3 with
The top of the second supply lines 32 is respectively adjacent to setting first electrode 111 and second electrode 112.It is double
First supply lines 31 of line supply lines 3 and the top of the second supply lines 32 are also respectively adjacent to setting
The coil 122 of first coil 121 and second.
In practice, for the ease of using, by electric field detector 11 (including first electrode 111
With second electrode 112) and magnetic field detector 12 (including the coil 122 of first coil 121 and second)
It is integrated into same module 13.Thus, only need will comprising first electrode 111, second electrode 112,
The module 13 of the coil 122 of first coil 121 and second be positioned adjacent to the first supply lines 31 with
The part of second supply lines 32, and measure and correction means, you can reach correct power consumption gauge
Calculate.
In the diagram, first electrode 111 be arranged at the first supply lines 31 and first coil 121 it
Between, but the present invention not therefore restriction.Second electrode 112 is arranged at the second supply lines 32 and
Between two coil 122, but therefore the present invention does not also limit.Substantially, two electrodes (
One electrode 111, second electrode 112) relative to two coils (first coil 121, the second line
Circle relative position 122) has no effect on the result of detecting.Because, first electrode 111, second
Electrode 112 is that (the first supply lines 31, second for being subject to supply lines 3 is powered with regard to electric field detecting
The impact of the variable voltage (or referred to as current potential) of line 32).Also, first coil 121,
Two coil 122 is that it is subject to the first supply lines 31, second of supply lines 3 with regard to magnetic field detecting
The electric current of supply lines 32 is affected, and here is especially pointed out, the line of first coil 121 and second
Circle 122 direction of winding conversely, first coil 121 with the second coil 122 according to identical sensing
The sense of current and coupled in series, to obtain the induced-current corresponding to live wire and the electric current of the neutral conductor
Signal SI.
Based on the explanation of Fig. 2 to Fig. 4, electric field detector 11 and the magnetic field of detecting unit 1 are detected
Device 12 is arranged at and keeps the position of non-contacting specific range D, such as described spy with supply lines 3
Set a distance D is the beeline for measuring supply lines to detecting unit 1, is more than 15 millimeters
(mm)。
In the diagram, magnetic field detector 12 further includes the first magnetic conductance element 121M and the second magnetic conductance
Element 122M, first coil 121 is set around the first magnetic conductance element 121M, the second coil 122
It is set around the second magnetic conductance element 122M.The magnetic conductance element is typically silicon steel sheet or iron oxide or magnetic
Iron, is generally referred to as with iron core, to help coil to concentrate the magnetic line of force.The present invention does not limit described
The shape of magnetic conductance element, and one of ordinary skill in the art should be readily understood by magnetic conductance element
Implementation, repeats no more.
Embodiment two
The present embodiment is the embodiment of the method for measuring power consumption.
Fig. 5 is refer to, Fig. 5 is the flow process of the method for the measurement power consumption that present example is provided
Figure.The method of measurement power consumption is used for measuring being transmitted by the first supply lines and the second supply lines
Active power, its can be applicable to previous embodiment measurement power consumption device.The method bag
Include following steps.First, in step s 110, by first electrode (111) and second electrode
(112) it is respectively provided with and is adjacent to the first supply lines and the second supply lines, and by first coil (121)
It is respectively provided with the second coil (122) and is adjacent to the first supply lines and the second supply lines, wherein the
One coil (121) is contrary with the direction of winding of the second coil (122).In one embodiment,
With reference to aforesaid Fig. 3, in comparison with above-mentioned step S110, first coil (121) is for feeling
Answer the first magnetic field (M1) produced by the electric current of the first supply lines and obtain the first induced-current side
To (D1), the second coil (122) is for sensing second produced by the electric current of the second supply lines
Magnetic field (M2) and obtain the second inductive current direction (D2), wherein the first magnetic field (M1)
In the direction opposite the direction of the second magnetic field (M2), the first inductive current direction (D1) and second
Inductive current direction (D1) is identical.Also, in practice, step S110 more may include, is made
One coil (121) is set around the first magnetic conductance element (121M), makes the second coil (122) winding
In the second magnetic conductance element (122M), with reference to shown in Fig. 4 of previous embodiment.
Then, in the step s 120, the current potential and second electrode of first electrode (111) are obtained
(112) potential difference of current potential and produce induced voltage signal (SV).Then, in step S130
In, by first coil (121) with the second coil (122) according to identical inductive current direction
Coupled in series, to obtain corresponding to the first supply lines and the induced-current of the electric current of the second supply lines
Signal (SI).
Next, in step S140, calculating induced voltage signal (SV) and induced-current
Phase difference between signal (SI) to obtain power factor (PF), and using computing unit (2)
Calculate according to induced voltage signal (SV), sensor current signal (SI) and power factor (PF)
Obtain active power.The step of active power is obtained in (S140), induced voltage signal (SV)
It is power factor (PF) with the cosine value of the phase difference between sensor current signal (SI), counts
Unit (2) is calculated by induced voltage signal (SV), sensor current signal (SI) and power factor
(PF) it is multiplied to obtain active power.In addition, first after the device for arranging measurement power consumption
When using, following steps are more may include after step S140, computing unit (2) is by induced electricity
Signal (SV), sensor current signal (SI) are pressed in comparison with look-up table (LUT), with to active
Performance number is corrected.
Embodiment three
The present embodiment is device of the device with non-contact measurement power supply situation for measuring power consumption
Another embodiment.
Referring again to Fig. 1, in the present embodiment, supply lines 3 changes is powered with single-phase three-wire 220V
As a example by line gauge lattice, supply lines 3 includes the first supply lines, the second supply lines and ground wire (G), the
One supply lines and the second supply lines are respectively first live wires (L1) of single-phase three-wire 220V supply lines
With the second live wire (L2).Fig. 6 is refer to, single-phase three-wire 220V has two live wires and difference
180 degree, can be considered the effect that single-phase-two-wire has the sense of current to be one-in-and-one-out because of loop structure,
It is as shown in Figure 7 to the wiring for loading.
Then, Fig. 8 is refer to, similar to the embodiment of Fig. 2, the first of electric field detector 11
The supply lines of electrode 111 and first (the first live wire L1) is according to capacity effect in first electrode 111
On cause the first current potential V1, and the supply lines 32 (the second live wire L2) of second electrode 112 and second
The second current potential V2 is caused in second electrode 112 according to capacity effect.Sensing in fig. 8
Voltage signal SV represents the potential difference (V1-V2) of the first current potential V1 and the second current potential V2.
Then, Fig. 9 is refer to, similar to the embodiment of Fig. 3, power supply 4 ' is using the first power supply
Line (the first live wire L1) is with the second supply lines (the second live wire L2) delivering power to load 6.
Magnetic field detector 12 has the coil 122 of first coil 121 and second, first coil 121 and the
Two coil 122 is respectively provided with and is adjacent to the first supply lines (the first live wire L1) and the second supply lines
(the second live wire L2), the direction of winding of the coil 122 of first coil 121 and second is conversely, first
Coil 121 and the second coil 122 coupled in series according to identical inductive current direction, to obtain
Corresponding to the first live wire L1 and sensor current signal SI of the electric current of the second live wire L2.
Then, detecting unit 1 can be produced simulation by the computing unit 2 of Fig. 1 using sampling mechanism
The induced voltage signal SV and sensor current signal SI of property is converted to digital signal to enter line number
Word is calculated and recorded.The content of induced voltage signal SV and sensor current signal SI, and it is right
It calculates the mode for processing, and refer to the explanation of preceding embodiment, repeats no more.
In sum, the device and method of the measurement power consumption that the embodiment of the present invention is provided, profit
With the voltage change on the principle inductive power supply line of two electrodes according to capacity effect, and utilize two
Curent change on individual coil-induced supply lines, obtain supply lines electric current and voltage change it
After power factor is obtained, therefore active power can be obtained.The device of measurement power consumption is detectd
Surveying unit neighbouring in a modular fashion can be arranged at the supply lines that must be measured.Based on this noncontact
The measurement of formula, the device and method of this measurement power consumption does not have the impedance loss of wire type measurement,
Also it is not in contact with the potential danger leaked electricity.
Embodiments of the invention are the foregoing is only, it is not used for limiting to the protection model of the present invention
Enclose.
Claims (15)
1. it is a kind of measurement power consumption device, for measuring the active power that supply lines is transmitted,
The supply lines has further included the first supply lines and the second supply lines, and the dress of the measurement power consumption
Put including a detecting unit and a computing unit, the computing unit is electrically connected with the detecting unit,
An induced voltage signal and a sensor current signal that the computing unit is produced according to the detecting unit
A power factor is obtained, and according to the induced voltage signal, the sensor current signal and the power
Factor obtains the active power, it is characterised in that：
The detecting unit has an electric field detector and a magnetic field detector, for being arranged adjacently to
First supply lines and second supply lines, wherein the electric field detector have a first electrode with
One second electrode, the magnetic field detector has a first coil and one second coil；
Wherein, the first electrode and the second electrode be respectively provided be adjacent to first supply lines with
Second supply lines, the first electrode and first supply lines according to capacity effect this first
One first current potential is caused on electrode, the second electrode is with second supply lines according to capacity effect
One second current potential, the induced voltage signal is caused to be first current potentials and be somebody's turn to do in the second electrode
The potential difference of the second current potential；
Wherein, the first coil and second coil be respectively provided be adjacent to first supply lines with
The direction of winding of second supply lines, the first coil and second coil is conversely, the First Line
Circle with second coil according to identical inductive current direction coupled in series, with acquisition corresponding to this
The sensor current signal of the electric current of the first supply lines and second supply lines.
2. it is according to claim 1 measurement power consumption device, it is characterised in that the sense
The cosine value for answering the phase difference between voltage signal and the sensor current signal is power factor,
The active power is corresponding to the induced voltage signal, the sensor current signal and the power factor
Product.
3. it is according to claim 1 measurement power consumption device, it is characterised in that the magnetic
Field detector further includes one first magnetic conductance element and one second magnetic conductance element, the first coil winding
In the first magnetic conductance element, second coil is set around the second magnetic conductance element.
4. the device of measurement power consumption according to claim 1, it is characterised in that this
One coil is used for one first magnetic field sensed produced by the electric current of first supply lines and obtains one the
One inductive current direction, second coil is used for sensing produced by the electric current of second supply lines
One second magnetic field and obtain one second inductive current direction, wherein first magnetic field is in opposite direction
In the direction in second magnetic field, first inductive current direction and the second inductive current direction phase
Together.
5. it is according to claim 1 measurement power consumption device, it is characterised in that the meter
Unit is calculated by the induced voltage signal, the sensor current signal in comparison with a look-up table, with to this
Active power value is corrected.
6. a kind of method of measurement power consumption, for measuring first supply lines and one the of supply lines
The active power that two supply lines are transmitted, it is characterised in that：
The method includes：
One first electrode and a second electrode are respectively provided be adjacent to first supply lines with this
Two supply lines, and a first coil and one second coil are respectively provided with are adjacent to first power supply
Line and second supply lines, wherein first coil is contrary with the direction of winding of second coil；
Obtain the potential difference of the current potential of the first electrode and the current potential of the second electrode and produce a sense
Answer voltage signal；
By the first coil and second coil according to identical inductive current direction coupled in series,
Believed with the induced-current obtained corresponding to first supply lines and the electric current of second supply lines
Number；And
According to the phase difference between the induced voltage signal and the sensor current signal obtaining a work(
Rate factor, and using a computing unit according to the induced voltage signal, the sensor current signal with
The power factor is calculated and obtains the active power.
7. it is according to claim 6 measurement power consumption method, it is characterised in that obtaining
In the step of obtaining the active power, between the induced voltage signal and the sensor current signal
The cosine value of phase difference is power factor, and the computing unit is by the induced voltage signal, the sensing
Current signal is multiplied to obtain the active power with the power factor.
8. it is according to claim 6 measurement power consumption method, it is characterised in that the survey
The method of amount power consumption is further included：
The computing unit by the induced voltage signal, the sensor current signal in comparison with a look-up table,
To be corrected to the active power value.
9. it is according to claim 6 measurement power consumption method, it is characterised in that will
The first coil is respectively provided with second coil and is adjacent to first supply lines with second power supply
In the step of line, the first coil is used for sensing one the produced by the electric current of first supply lines
One magnetic field and obtain one first inductive current direction, second coil be used for sense this second power supply
One second magnetic field produced by the electric current of line and obtain one second inductive current direction, wherein this
The direction in the direction opposite second magnetic field in one magnetic field, first inductive current direction with this
Two inductive current directions are identical.
10. it is according to claim 6 measurement power consumption method, it is characterised in that
The first coil and second coil are respectively provided with and are adjacent to first supply lines with second confession
Further including in the step of electric wire makes the first coil be set around one first magnetic conductance element, make this second
Coil is set around one second magnetic conductance element.
11. a kind of contactless power supply situation arrangement for detecting, for measuring supply lines simultaneously
Induced voltage signal and sensor current signal, the supply lines further included one first supply lines with
And one second supply lines, it is characterised in that：
The power supply situation arrangement for detecting is arranged at and keeps a non-contacting specific range with the supply lines
Position, and with an electric field detector and a magnetic field detector；
There is the electric field detector first electrode to be set with the specific range respectively with a second electrode
Put and be adjacent to first supply lines and second supply lines, the first electrode and first supply lines
One first current potential is caused in the first electrode according to capacity effect, the second electrode with this
Two supply lines cause one second current potential according to capacity effect in the second electrode, and this is first electric
Position is the induced voltage signal with the potential difference of second current potential；
Wherein, the magnetic field detector has a first coil specific with this respectively with one second coil
Distance is positioned adjacent to first supply lines and second supply lines, the first coil with this second
The direction of winding of coil conversely, the first coil with second coil according to identical induced-current side
To and coupled in series, to obtain the induced electricity corresponding to first supply lines and second supply lines
Stream signal.
12. contactless power supply situation arrangement for detecting according to claim 11, it is special
Levy and be, the first coil is set around one first magnetic conductance element, second coil is set around one
Two magnetic conductance elements.
13. contactless power supply situation arrangement for detecting according to claim 11, it is special
Levy and be, the specific range is to measure the supply lines to the contactless power supply situation detecting dress
The beeline put, the beeline is more than 15 millimeters.
A kind of 14. devices of non-contact measurement supply current, are transmitted for measuring supply lines
The magnitude of current, the supply lines has further included the first supply lines and the second supply lines, and the measurement
The device of supply current includes a detecting unit, it is characterised in that：
The detecting unit has a magnetic field detector, wherein, the magnetic field detector has one first
Coil and one second coil；And the first coil and second coil be respectively provided be adjacent to this
One supply lines and second supply lines, and the direction of winding phase of the first coil and second coil
Instead, the first coil and second coil according to identical inductive current direction coupled in series, with
Obtain the sensor current signal corresponding to first supply lines and the electric current of second supply lines.
The device of 15. non-contact measurement supply currents according to claim 14, it is special
Levy and be, the first coil is set around one first magnetic conductance element, second coil is set around one
Two magnetic conductance elements.
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| CN201510643879.6A CN106569025A (en) | 2015-10-08 | 2015-10-08 | Device of measuring power consumption, device and method of measuring power supply status in non-contact manner |
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