CN202600047U - High-voltage three-phase electric energy metering device - Google Patents
High-voltage three-phase electric energy metering device Download PDFInfo
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- CN202600047U CN202600047U CN 201220242309 CN201220242309U CN202600047U CN 202600047 U CN202600047 U CN 202600047U CN 201220242309 CN201220242309 CN 201220242309 CN 201220242309 U CN201220242309 U CN 201220242309U CN 202600047 U CN202600047 U CN 202600047U
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Abstract
The utility model provides a high-voltage three-phase electric energy metering device. An appointed phase is determined in high-voltage three-phase alternating current, and other two phases are non-appointed phases; an electric energy metering unit is positioned at a high-level end of the appointed phase; an emission module is arranged in the electric energy metering unit; a current signal acquisition part comprises two current sensors, namely a first current sensor L1 and a second current sensor L2; primary coils of the first current sensor L1 and the second current sensor L2 are arranged at the high levels of the non-appointed phases; secondary coils of the first current sensor L1 and the second current sensor L2 are connected to the electric energy metering unit; a voltage signal acquisition part adopts two interphase voltage sharers, namely a first interphase voltage sharer U1 and a second interphase voltage sharer U2; the first interphase voltage sharer U1 and the second interphase voltage sharer U2 are respectively connected between the two non-appointed phases and the appointed phase; low-voltage arms of the first interphase voltage sharer U1 and the second interphase voltage sharer U2 are connected to the high-level end of the appointed phase; high-voltage arms are connected with the non-appointed phases; and voltage sharing arms are connected with the electric energy metering unit.
Description
Technical field
The utility model belongs to the electric energy metrical technical field, is specifically related to a kind of high pressure three-phase electric energy metering device.The electric power meter that specially refers to a kind of electric quantity acquisition, data processing and communicate by letter and all realize at the same point noble potential.
Background technology
There are a lot of problems in existing electric energy metrical technology.The quantity of considering high-voltage electric-energy meter is huge especially, and the consequence that these problems are brought can be very serious.
At first, existing high pressure measurement device is that electric current, voltage transformer (VT) and low-voltage electric energy table by separation constitutes together.The error of electric current, voltage transformer (VT) and low-pressure meter meter can only be known, the global error of high pressure measurement device can not be directly measured.Secondly, the quantity of electric power mutual-inductor consume material, particularly metal material is big, does not meet current international and domestic energy-saving and cost-reducing requirement.The 3rd, the low-pressure meter meter is arranged on electronegative potential, and wiring error takes place easily, causes the electric weight incorrect posting.Particularly be not easy to avoid the generation of stealing activity.A large amount of stealings is one of power supply enterprise's profit main reasons for decrease.The 4th, the use of ferromagnetic type electric power mutual-inductor causes ferroresonance easily, thereby brings out the electric system major accident.The 5th, existing mutual inductor and WT-MSR volume be big, it is big to take up room, and is badly in need of improving.The 6th, more existing new technologies can partly address the above problem, but they have brought some new problems again.For example: the three-phase electric weight is done metering respectively and always added the problem of bringing synchronous difficulty big, the complicated problems of communicating by letter, relatively poor too complicated low problem of WT-MSR product quality and the corresponding too high problem of cost of goods manifactured of causing of problem, technology of data processing accuracy.
Present existing high voltage electric energy gauging method has a variety of.Can be divided into following three types:
First kind, with traditional electromagnetic type electric current, voltage transformer (VT) high voltage, big electric current are reduced respectively and become general low-voltage, little electric current (for example: 100 volts of rated voltages, rated current 5 peace or 1A), carry out electric energy metrical with the low-voltage electric energy table then.The advantage of this technology is: it is a kind of technology of classics.The accuracy of measuring and constant product quality.Its shortcoming is a lot: the labor material particularly non-ferrous metal, can't the overall approval error, the ferroresonance accident takes place easily, the accuracy of measuring is low.
Second kind, substitute traditional electromagnetic type mutual inductor with unconventional voltage and current sensor, constitute electric power meter together with low-voltage standards or non-standard electric energy meter.Present how tame high-voltage electric energy meter just uses this principle to process.The characteristics of this type technology are, the sensing of electric energy metrical, data processing and communicate by letter and all accomplish in low-pressure side.Its advantage is electric current, voltage sensor miniaturization, and sensor and low-voltage electric energy table are integrated.This causes the saving of material and the minimizing of volume.Its shortcoming is that this technology is the same with traditional know-why in itself fully.Technology is the progress of essence not.
The third utilizes non-traditional electric current, voltage sensor is placed hot end, obtains A, B, C voltage in three phases and current signal in the high-pressure side.The electric energy metrical unit that the chip that uses a computer becomes with electronics configuration, A, B, C three relative each phase current, the voltage at high-tension electricity carries out signal Processing and calculating respectively, obtains the electric flux of every phase.At last, three-phase electric flux is separately always added and adds up obtain the three-phase electric energy metering result.The principal feature of this technology is: the sensing of electric energy metrical, data processing and communicate by letter and all accomplish in the high-pressure side.It can cause material particularly metal material significantly save.The most outstanding advantage is that this technology can cause the fusion fully of sensor and table meter.Be easy to realize the integral verification.Its another advantage is, the ability that whole device anti-is struck by lightning with switching overvoltage greatly promotes.Its shortcoming is: three-phase electric energy metering is to conduct to B by the electric energy metrical that carries out separately mutually at A, C to do mutually and always add and add up and accomplish.This will cause the increase of alternate optical fiber communication passage.Except increasing manufacturing cost, this structure also can increase the fault probability of happening of high-voltage electric energy meter.
More than measure according to so-called " genuine standard ".To the central point isolated neutral system, can also utilize " two meter technique " to accomplish three electric energy metricals.The principal feature of this technology is: use current transformer, voltage transformer (VT) and a metering units less, save metal material than genuine standard.
Number of patent application is that " high voltage electric energy direct metered system and method " current acquisition module of 200810002310.1 lays respectively at A, C mutually, and with A, C same potential, metering units is divided into two parts, lays respectively at A, C phase, comprehensively adds up mutually at B then; Not only metering units is many in this scheme, and needs the communication link between metering units spare, has improved manufacturing cost, and complex structure has reduced the reliability of function.
Summary of the invention
The purpose of the utility model is to solve above-mentioned technical matters, and a kind of high pressure three-phase electric energy metering device is provided.Three-phase high-potential current and voltage sensing signal can be connected directly on a certain noble potential mutually, make the electric energy metrical unit on this noble potential realize electric energy metrical.Thereby the problem and shortage of avoiding existing electric energy gauging method to exist.
The technical scheme of the utility model: the high pressure three-phase electric energy metering device of the utility model comprises current signal collecting part, voltage signal acquisition part and electric energy metrical unit; Confirm that in the high pressure three-phase alternating current is specified a phase, other two is non-appointment phase mutually; The electric energy metrical unit is positioned at the hot end of specifying phase, and electric energy metrical is provided with transmitter module in the unit, can realize the wireless telecommunications of data; The current signal collecting part comprises two current sensors; The first current sensor L1 and the second current sensor L2; The first current sensor L1 and the second current sensor L2's once is non-appointment current potential mutually; The secondary coil of the first current sensor L1 and the second current sensor L2 is connected to the electric energy metrical unit, for specifying the phase current potential; Voltage signal acquisition partly adopts two alternate voltage dividers; The first alternate voltage divider U1 and the second alternate voltage divider U2; Between the first alternate voltage divider U1 and the second alternate voltage divider U2 are connected to two non-appointments and specify mutually; The low-voltage arm of the first alternate voltage divider U1 and the second alternate voltage divider U2 is connected with appointment mutually, and high-voltage arm is connected with non-appointment, and the low-voltage arm voltage division signal inserts the electric energy metrical unit.
Described alternate voltage divider uses non-ferromagnetic type sensor, like capacitive divider or resitstance voltage divider or RC divider.
Described current sensor first and second between insulation isolate, withstand voltage level is according to the voltage between phases design levels.
Described high pressure three-phase electric energy metering device utilizes the encapsulation of metallic shield box with described electric energy metrical unit, working power and communication unit.
The working power of described electric energy metrical unit is supplied with by the three-phase alternating current dividing potential drop, comprises voltage divider V1 and the 4th alternate voltage divider V2 between third phase, and the low-voltage arm of voltage divider V1 and the 4th alternate voltage divider V2 all is connected to working power between third phase.
Described high pressure three-phase electric energy metering device; Utilize insulating material to be encapsulated in one the genus shielding box of voltage divider V1 and the 4th alternate voltage divider V2 and electric energy metrical unit, working power and communication unit between described current signal collecting part, voltage signal acquisition part, third phase, form the electric power meter of a direct access type of high voltage.
The advantage of the utility model:
1. current signal has sensed the noble potential of specifying phase with the method for insulation isolation, and this has established theoretic basic point and basis for the conceptual design of the utility model; Metering required voltage, current signal serve as simulation ground to specify mutually all; Function of measuring can be concentrated realization; Saved the metering circuit that is positioned at non-appointment phase; Save the communication link in original scheme, saved manufacturing cost and improved the reliability of function, and reduced the operation power consumption of entire equipment.
2. voltage signal has sensed the noble potential of specifying phase with the method for voltage divider; High pressure is got and can be realized more easily by voltage divider; Voltage signal voltage divider and current sensor load are the high impedance electronic circuit, and design capacity is extremely low, reduce greatly with respect to traditional voltage, current transformer volume weight; Make the product small volume and less weight, practiced thrift manufacturing cost significantly.
3. principle of compositionality, hardware, software and the algorithm, inexpensive device etc. of low pressure three-phase electric energy meter have been transplanted to and have been specified noble potential mutually; On noble potential, realize " two meter technique " electric energy measurement principle; The realization of function of measuring and traditional low-pressure meter meter are similar; Can use for reference at present and have ripe experience, and check system also can be general.Also help stabilizing and increasing of new product quality.
4. electric current, voltage signal acquisition part are encapsulated in the metallic shield box of noble potential with electric energy metrical unit, working power and communication unit.Purpose is to improve the anti-electromagnetic interference capability of device. guarantee and improve the High-Voltage Insulation level of each parts and device.
The utility model is compared with prior art:
The device volume of the utility model littler, take up room forr a short time, structure is simpler;
2. save more materials.Reduce high pressure body production cost;
3. implement the whole verification of error of new high voltage electric power meter more easily;
4. the accuracy of the utility model high-voltage electric-energy meter is higher.
Description of drawings
Fig. 1 is the principle of device block diagram of the utility model.
Embodiment
The utility model is a kind of direct access type electric power meter of making according to " two meter technique " principle in the 3-35kV high-pressure side.
Fig. 1 is the principle of device block diagram of the utility model: a kind of high pressure three-phase electric energy metering device of the utility model comprises current signal collecting part, voltage signal acquisition part and electric energy metrical unit; Confirm that in the high pressure three-phase alternating current is specified a phase, other two is non-appointment phase mutually; Electric energy metrical is positioned at the hot end of specifying phase, and electric energy metrical is provided with transmitter module in the unit; The current signal collecting part comprises two current sensors; The first current sensor L1 and the second current sensor L2; The first current sensor L1 and the second current sensor L2's once is non-appointment current potential mutually; The secondary coil of the first current sensor L1 and the second current sensor L2 is connected to the electric energy metrical unit, for specifying the phase current potential; Voltage signal acquisition partly adopts two alternate voltage dividers; The first alternate voltage divider U1 and the second alternate voltage divider U2; Between the first alternate voltage divider U1 and the second alternate voltage divider U2 are connected to two non-appointments and specify mutually; The low-voltage arm of the first alternate voltage divider U1 and the second alternate voltage divider U2 is connected with appointment mutually, and high-voltage arm is connected with non-appointment, and the low-voltage arm voltage division signal inserts the electric energy metrical unit.
Described alternate voltage divider uses capacitive divider or resitstance voltage divider or RC divider.The second alternate voltage divider U1 that first alternate voltage divider U1 that C1, C2 form among the figure and C3, C4 form.
Or resitstance voltage divider: the second alternate voltage divider U1 that first alternate voltage divider U1 that R1, R2 form among the figure and R3, R4 form.
Or RC divider: the second alternate voltage divider U1 that first alternate voltage divider U1 that R5, C5 form among the figure and R6, C6 form.
Use insulating material to isolate between first and second coil of described current sensor, withstand voltage level is according to the voltage between phases design levels.
The working power of described electric energy metrical unit is supplied with by the three-phase alternating current dividing potential drop; Comprise voltage divider V1 and the 4th alternate voltage divider V2 between the third phase of being made up of two groups of capacitor C B, CL, voltage divider V1 and the 4th alternate voltage divider V2 are connected to working power between third phase.
Described electric energy metrical unit, working power and communication unit are utilized the encapsulation of metallic shield box.Its role is to high-voltage electromagnetic field is shielded, weaken or avoid interference and the influence of high-voltage electromagnetic field these parts and circuit thereof.
Described high pressure three-phase electric energy metering device; Utilize insulating material to be encapsulated in one in the metallic shield box of voltage divider V1 and the 4th alternate voltage divider V2 and electric energy metrical unit, working power, communication unit between described current signal collecting part, voltage signal acquisition part, third phase, form the electric power meter of a direct access type of high voltage.
Fig. 1 is to serve as the theory diagram of appointment phase mutually with B.
When specifying be the A phase time mutually, non-appointment be the B phase mutually with C mutually.Electric current is ia, ib;
When specifying be the C phase time mutually, non-appointment be the A phase mutually with B mutually.Electric current is ia, ib.
The current sensing signal of the non-appointment phase of the utility model is incorporated into the noble potential of specifying phase (is example with B mutually) through the insulation isolating means.Current sensor can adopt the various coil formations that magnetic core arranged or do not have magnetic core.Use and do insulation between conductor and the secondary coil lead of the primary current that high-intensity insulating material will be through coil and isolate.Make the voltage between phases that can tolerate three-phase electricity between primary current conductor and the secondary coil conductor.This is engraved in the primary current lead on the non-appointment phase current potential, with the lead of secondary coil cause specify mutually and make it current potential for specifying the noble potential of phase.So that be in same current potential, possibility is provided for signal focuses on the voltage sensor secondary lead that will obtain.
In Fig. 1, voltage sensor is realized through utilizing voltage divider.The novelty key point of voltage sensor is the branch pressure arm of voltage divider (getting the small-signal end) is arranged on the appointment phase.That is, with low-voltage arm one end of voltage divider and specify mutually that (is example with B mutually) connects.Alternate voltage is mainly carried by the high-voltage arm of voltage divider.The purpose of doing like this is the needed voltage between phases sensing of electric energy metrical pending to specifying the phase noble potential to concentrate.
After the hot end of specifying phase has obtained above-mentioned voltage sensing signal and current sensing signal, can give the electric energy metrical cell processing.The principle of compositionality of electric energy metrical unit and method and low-voltage electric energy epiphase are together.The electric energy metrical unit can be always to add after the single-phase processing (principle is shown in formula 1) to obtain the three-phase electric energy value.Also can be directly to the disposable processing of whole signals (two meter technique of principle shown in formula 2) thus obtain the three-phase electric energy value.The electric energy metrical unit possesses metering memory function as a result.Electric energy metrical unit in the noble potential operation is different with the running environment of low-voltage electric energy table.Need to the electric energy metrical unit carry out specialty electromagnetic screen protection design.In addition, the design of the power consumption of electric energy metrical unit also is different from the method for traditional low-voltage electric energy table.
As shown in Figure 1, the enforcement of the utility model also need be considered the power supply design proposal of electric energy metrical unit.Power supply can through special-purpose or public voltage divider get can and the supply of electrical energy metering units, make the electric energy metrical unit can operate as normal.Power supply is to be operated in the high-pressure side of specifying phase equally.Power supply also need provide working power for the communication unit that the back is mentioned except for the electric energy metrical unit provides the working power.So the reliability of power supply self and power guarantee that ability is an important design effort.
As shown in Figure 1, reach in the device of processing in view of the above in the utility model scheme, sensor, electric energy metrical unit all are on the noble potential of specifying phase.So the electric energy metrical result need be delivered to the device or the network of electronegative potential (also not discharging other noble potential) appointment through communication, offer electric energy metrical result's the person of needs.Communication unit can use (including but not limited to) optical fiber, small wireless, infrared and GPRS to accomplish as telecommunication media and specified device or network and communicate by letter; Thereby mail to object to the metering and the measurement result of electric flux and other electric parameters, thereby accomplish the communication transmission of metering result from the hot end to the cold end.
As shown in Figure 1, the WT-MSR of the utility model scheme and formation thereof is to be made up of voltage sensor, current sensor and electric energy metrical unit etc.Can they be packaged together, form an incorporate single unit system.Also can encapsulate respectively and be fabricated to two or more splits, when in use they are connected to become a single unit system.
The utility model lithium battery capable of using and/or ultracapacitor are as standby power supply, and the electric energy metrical unit is stored and memory electric energy value during in order to power failure or accident.
The core of the utility model is at the hot end of specifying phase the electric energy metrical unit to be set, and it serves as simulation ground to specify the phase current potential all that the First Astronautic Research Institute for Measurement and Test needs all signals, and therefore, electric energy metrical can all be accomplished in appointment mutually.Therefore, it serves as to simulate ground to specify the phase current potential all that every First Astronautic Research Institute for Measurement and Test needs all signals, all belongs to the protection domain of the utility model.
Claims (9)
1. high pressure three-phase electric energy metering device; Comprise current signal collecting part, voltage signal acquisition part, electric energy metrical unit, working power and communication unit; It is characterized in that: confirm that in the high pressure three-phase alternating current is specified a phase, other two is non-appointment phase mutually; Electric energy metrical unit, working power and communication unit are positioned at the hot end of specifying mutually, and communication unit is realized communication of data; The current signal collecting part comprises two current sensors; The first current sensor L1 and the second current sensor L2; The primary winding of the first current sensor L1 and the second current sensor L2 is a non-appointment current potential mutually; The secondary coil of the first current sensor L1 and the second current sensor L2 is connected to the electric energy metrical unit, for specifying the phase current potential; Voltage signal acquisition partly adopts two alternate voltage dividers; The first alternate voltage divider U1 and the second alternate voltage divider U2; Between the first alternate voltage divider U1 and the second alternate voltage divider U2 are connected to two non-appointments and specify mutually; The low-voltage arm of the first alternate voltage divider U1 and the second alternate voltage divider U2 is connected with appointment mutually, and high-voltage arm is connected with non-appointment, and the low-voltage arm voltage division signal inserts the electric energy metrical unit.
2. high pressure three-phase electric energy metering device according to claim 1 is characterized in that: alternate voltage divider uses non-ferromagnetic type sensor, like capacitive divider or resitstance voltage divider or RC divider.
3. high pressure three-phase electric energy metering device according to claim 1 and 2 is characterized in that: current sensor first and second between insulation isolate, withstand voltage level is according to the voltage between phases design levels.
4. high pressure three-phase electric energy metering device according to claim 1 and 2; It is characterized in that: the working power of electric energy metrical unit is supplied with by the three-phase alternating current dividing potential drop; Comprise voltage divider V1 and the 4th alternate voltage divider V2 between third phase, the low-voltage arm of voltage divider V1 and the 4th alternate voltage divider V2 all is connected to the input end of working power between third phase.
5. high pressure three-phase electric energy metering device according to claim 1 and 2 is characterized in that: described electric energy metrical unit, working power and communication unit are utilized the encapsulation of metallic shield box.
6. high pressure three-phase electric energy metering device according to claim 1 and 2; It is characterized in that: utilize insulating material to be encapsulated in one described current signal collecting part, voltage signal acquisition part, electric energy metrical unit, working power and communication unit, form the electric power meter of a direct access type of high voltage.
7. high pressure three-phase electric energy metering device according to claim 3; It is characterized in that: the working power of electric energy metrical unit is supplied with by the three-phase alternating current dividing potential drop; Comprise voltage divider V1 and the 4th alternate voltage divider V2 between third phase, the low-voltage arm of voltage divider V1 and the 4th alternate voltage divider V2 all is connected to the input end of working power between third phase.
8. high pressure three-phase electric energy metering device according to claim 4; It is characterized in that: utilize insulating material to be encapsulated in one voltage divider V1 and the 4th alternate voltage divider V2 between described current signal collecting part, voltage signal acquisition part, electric energy metrical unit, working power and communication unit, third phase, form the electric power meter of a direct access type of high voltage.
9. high pressure three-phase electric energy metering device according to claim 5; It is characterized in that: utilize insulating material to be encapsulated in one the genus shielding box of voltage divider V1 and the 4th alternate voltage divider V2 and electric energy metrical unit, working power and communication unit between described current signal collecting part, voltage signal acquisition part, third phase, form the electric power meter of a direct access type of high voltage.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220242309 CN202600047U (en) | 2012-05-28 | 2012-05-28 | High-voltage three-phase electric energy metering device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220242309 CN202600047U (en) | 2012-05-28 | 2012-05-28 | High-voltage three-phase electric energy metering device |
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| CN202600047U true CN202600047U (en) | 2012-12-12 |
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| CN 201220242309 Expired - Lifetime CN202600047U (en) | 2012-05-28 | 2012-05-28 | High-voltage three-phase electric energy metering device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103941082A (en) * | 2014-04-08 | 2014-07-23 | 武汉国测恒通智能仪器有限公司 | High-voltage electric energy direct metering device and method with double-channel data redundancy |
| CN106771575A (en) * | 2017-01-03 | 2017-05-31 | 陈永山 | A kind of three element high-voltage meters |
-
2012
- 2012-05-28 CN CN 201220242309 patent/CN202600047U/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103941082A (en) * | 2014-04-08 | 2014-07-23 | 武汉国测恒通智能仪器有限公司 | High-voltage electric energy direct metering device and method with double-channel data redundancy |
| CN103941082B (en) * | 2014-04-08 | 2017-02-15 | 武汉国测恒通智能仪器有限公司 | High-voltage electric energy direct metering device and method with double-channel data redundancy |
| CN106771575A (en) * | 2017-01-03 | 2017-05-31 | 陈永山 | A kind of three element high-voltage meters |
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| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term |
Granted publication date: 20121212 |