CN101893668B - Three-phase three-wire and three-phase four-wire compatible electrical parameter signal measurement and process system - Google Patents
Three-phase three-wire and three-phase four-wire compatible electrical parameter signal measurement and process system Download PDFInfo
- Publication number
- CN101893668B CN101893668B CN2010102085256A CN201010208525A CN101893668B CN 101893668 B CN101893668 B CN 101893668B CN 2010102085256 A CN2010102085256 A CN 2010102085256A CN 201010208525 A CN201010208525 A CN 201010208525A CN 101893668 B CN101893668 B CN 101893668B
- Authority
- CN
- China
- Prior art keywords
- phase
- voltage
- terminal
- current
- connection terminal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Measurement Of Current Or Voltage (AREA)
Abstract
The invention relates to a three-phase three-wire and three-phase four-wire compatible electrical parameter signal measurement and process system, which is characterized in that the system consists of a voltage connecting terminal, a current connection terminal, a connection mode switch, a divider resistor, a signal process circuit and a microcontroller MCU, wherein the signal process circuit is formed by orderly connecting a voltage transformer, a voltage path filter, a current transformer, a current path filter and a single phase electrical parameter measurement chip in series; the system is provided with three sets of independent signal process circuits totally; the voltage connecting terminal is externally connected with a power grid and is internally connected with the voltage transformer; the current connection terminal is externally connected in series to a power gird phase line and is internally connected to the current transformer in sequence; the voltage connection terminal and the current connection terminal are internally connected to the signal process circuit according to the respective access so as to read the parameter values of the circuits to a microcontroller and calculate to obtain the three-phase electrical parameters. The technical scheme of the invention can reduce the manufacturing cost, simplify the management of production and storage as well as the sale and is convenient for a user to buy and select the type.
Description
Technical field
The present invention relates to electrical parameter signal measurement and process system, relate in particular to phase three-wire three and three-phase and four-line Campatible three phase electrical parameters signal measurement and process system.
Background technology
Three-phase alternating current electrical parameter measuring instrument table is divided into two types of three-phase three-wire system and three-phase four-wire systems.The mode of connection of this instrument of two types, signal processing method are all inequality; Therefore when design, production and use, need clearly distinguish; The two can not be compatible, must sell respectively or buy, takes care of respectively, take respectively, brings a lot of inconvenience for the management of production and sales and use.
In the signal processing technology of three-phase alternating current electric parameter measurement; Typical technical scheme is special chip such as the signal core processing devices such as ADE7758, ATT7026A and ATT7022A that adopt three phase electrical parameters to measure; But these chip prices are high, account for the larger proportion of device total cost.
Summary of the invention
The objective of the invention is to propose a kind of signal processing system scheme that adopts cheap single-phase electricity parameter measurement chip to realize measuring three phase electrical parameters in order to overcome above-mentioned deficiency, this system can compatible three-phase three-wire system and two kinds of modes of connection of three-phase four-wire system.Adopt technical scheme of the present invention can significantly reduce manufacturing cost, simplify production storage and the management of selling, make things convenient for the user to buy type selecting.
Realize that the technical scheme that above-mentioned purpose adopts is: a kind of Campatible three phase electrical parameters signal measurement and process system,, mode of connection change-over switch sub by voltage terminal, current terminal, divider resistance, signal processing circuit and microcontroller MCU form; Voltage terminal connects grid line outward, in connect mode for through being connected to voltage transformer (VT), voltage channel wave filter, single-phase electricity parameter measurement chip successively after the divider resistance parallel connection mode of connection change-over switch; Current terminal connects mode outward for by to being series at the electrical network phase line, in be linked as and be connected to current transformer, current channel wave filter, single-phase electricity parameter measurement chip successively; Voltage terminal and current terminal are by being connected to signal processing circuit in the path separately; The measured parameter value of signal processing circuit is read microcontroller MCU; Carry out comprehensive calculation process according to phase three-wire three or the determined mathematical relation of the three-phase and four-line mode of connection again, calculate three phase electrical parameters.
Said voltage terminal has 4; Be UA, UB, UC and UN, UA, UB and UC are external in A, B, the C phase exit of the secondary side of electrical network A, B, three phase lines of C or instrument external voltage mutual inductor respectively; UN connects three-phase four-wire system electrical network center line, or connects three-phase three-wire system UB.
Said current terminal has 6; Two a pair of; Be specially IA/IAR, IB/IBR, IC/ICR; IA/IAR be used to be connected in series electrical network A phase line or connect the secondary side exit of the current transformer on the outer A phase line of instrument, IB/IBR be used to be connected in series electrical network B phase line or connect the secondary side exit of the current transformer on the outer B phase line of instrument, IC/ICR be used to be connected in series electrical network C phase line or connect the secondary side exit of the current transformer on the outer C phase line of instrument.
Described signal processing circuit; Contact successively by voltage transformer (VT), voltage channel wave filter, current transformer, current channel wave filter and single-phase electricity parameter measurement chip and to constitute; Have 3 cover separate signal treatment circuits in the native system; Wherein: voltage transformer (VT) is a two-port network, and its secondary side is connected to the input of voltage channel wave filter as the voltage channel wave filter, and the output of voltage channel wave filter is connected to the voltage channel input end of single-phase electricity parameter measurement chip; Current transformer is a two-port network, and its primary side is connected to each phase current connection terminal IA/IAN, IB/IBN, IC/ICN respectively by signal processing circuit, and secondary side is connected to the input of current channel wave filter as the current channel wave filter; The output of current channel wave filter is connected to the current channel input end of single-phase electricity parameter measurement chip; The end of divider resistance RA is connected with the sub-UA of voltage terminal, and the other end is connected with the upper end of the primary side of voltage transformer (VT) 1A; The end of divider resistance RB is connected with mode of connection change-over switch connection terminal X, the other end be connected with the upper end of the primary side of voltage transformer (VT) 1B; The end of divider resistance RC is connected with the sub-UC of voltage terminal, and the other end is connected with the upper end of the primary side of voltage transformer (VT) 1C.Adopt divider resistance that tested voltage is carried out dividing potential drop, make the voltage attenuation of the primary side that is added in voltage transformer (VT) so that described voltage channel wave filter and single-phase electricity parameter measurement chip carry out signal Processing;
Described mode of connection change-over switch is a DPDT toggle switch with 6 connection terminals of SA, SB, SC, SN, X and Y, and connection terminal SA is connected with the sub-UA of voltage terminal; Connection terminal SB links to each other with the sub-UB of voltage terminal; Connection terminal SC is connected with the sub-UC of voltage terminal; Connection terminal SN is connected with the sub-UN of voltage terminal, also is connected with the lower end of the primary side of the lower end of the primary side of voltage transformer (VT) 1A and voltage transformer (VT) 1C; Connection terminal X is connected with divider resistance RB; Connection terminal Y is connected with the lower end of the primary side of voltage transformer (VT) 1B.When mode of connection change-over switch is upwards dialled; The closed conducting of connection terminal X and connection terminal SA, break off with connection terminal SB; The closed conducting of connection terminal Y and terminal SC, break off with connection terminal SN; When switch when setting aside, the closed conducting of connection terminal X and connection terminal SB, break off with connection terminal SA, connection terminal Y and the closed conducting of connection terminal SN, with connection terminal SC disconnection.
Described single-phase electricity parameter measurement chip; Has single-phase electricity parameter measurement function; Can measure current effective value, voltage effective value, current instantaneous value, the instantaneous voltage of single-phase AC; Can accumulate the active energy in the short time, and these parameter values can be delivered to microcontroller MCU through serial communication mode;
Logical communication link between the above-mentioned 3 cover signal processing circuits is: the measured parameter value of 3 single-phase electricity parameter measurement chips is read microcontroller MCU respectively; Carry out comprehensive calculation process according to phase three-wire three or the determined mathematical relation of the three-phase and four-line mode of connection again, calculate three phase electrical parameters.
The present invention has following beneficial effect: can utilize three single-phase electricity parameter measurement chips to realize the signal Processing to the three-phase alternating current electric parameter measurement; Can the meter point counting mutually with close mutually electrical quantity such as line current, line voltage, phase voltage, active power, reactive power, applied power, power factor, frequency, zero-sequence current, active energy, reactive energy or the like, the use of mode of connection change-over switch can realize the signal Processing to the electric parameter measurement under the three-phase three-wire system and the three-phase four-wire system mode of connection.
Description of drawings
Fig. 1 is the modular structure figure of Campatible three phase electrical parameters signal measurement and process system
Fig. 2 is the circuit connection diagram of Campatible three phase electrical parameters signal measurement and process system.
Among Fig. 2, be that voltage terminal is organized in 6 the frame of broken lines, include 4 the sub-UA of voltage terminal, UB, UC and UN, connect three phase lines of A, B, C and the electrical network center line of electrical network during three-phase four-wire system with line respectively; Electrical network does not have center line during three-phase three-wire system, with line UN is connected to UB, and UA, UB, UC is connected to three phase lines of A, B, C of electrical network with line respectively; It in 7 the frame of broken lines current terminal group; Include 6 totally three couples the sub-IA/IAR of current terminal, IB/IBR, IC/ICR; IA/IAR be used to be connected in series electrical network A phase line or connect the secondary side exit of the current transformer on the outer A phase line of instrument; IB/IBR be used to be connected in series electrical network B phase line or connect the secondary side exit of the current transformer on the outer B phase line of instrument, IC/ICR be used to be connected in series electrical network C phase line or connect the secondary side exit of the current transformer on the outer C phase line of instrument; 8 frame of broken lines is expressed as mode of connection change-over switch, and it is the DPDT toggle switch with 6 connection terminals, and switch is to setting aside during three-phase four-wire system, and switch is upwards dialled during three-phase three-wire system; RA, RB, RC are 3 divider resistances, are used for tested voltage is carried out dividing potential drop, make the voltage attenuation of the primary side that is added in voltage transformer (VT).9 is microcontroller.
Embodiment
Below in conjunction with Fig. 2 technical scheme of the present invention is further described, a kind of Campatible three phase electrical parameters signal measurement and process system is by the sub-UA of voltage terminal, UB, UC and UN; Three couples of sub-IA/IAR of current terminal, B/IBR and IC/ICR, connection terminal SA, SB, SC, SN, X and Y in the mode of connection change-over switch, 3 voltage transformer (VT) 1A, 1B and 1C; 3 divider resistance RA, RB and RC; 3 voltage channel wave filter 2A, 2B and 2C, 3 current transformer 5A, 5B and 5C, 3 current channel wave filter 4A, 4B and 4C; 3 single-phase electricity parameter measurement chip 3A, 3B and 3C, 1 microcontroller (9) is formed;
It is UA, UB, UC and UN that voltage terminal group (6) comprises 4 voltage terminal altogether; It is IA/IAR, IB/IBR, IC/ICR that current terminal group (7) comprises 3 pairs of current terminal of 6 compositions altogether; Mode of connection change-over switch (8) is a DPDT toggle switch with 6 connection terminals; Its 6 terminals are respectively SA, SB, SC, SN, X and Y, and switch is upwards dialled when being used for three-phase three-wire system, terminal X and the closed conducting of terminal SA, with terminal SB disconnection; The closed conducting of terminal Y and terminal SC, break off with terminal SN; Switch is to setting aside when being used for three-phase four-wire system, the closed conducting of terminal X and terminal SB, break off with terminal SA, terminal Y and the closed conducting of terminal SN, with terminal SC disconnection;
To voltage transformer (VT) (1A, 1B, 1C), voltage channel wave filter (2A, 2B, 2C), current transformer (5A, 5B, 5C), current channel wave filter (4A, 4B, 4C), single-phase electricity parameter measurement chip (3A, 3B, 3C) totally 5 kinds of devices be divided into 3 groups of A, B, C; The last letter of device identification on the same group is identical; The device that promptly is designated 1A, 2A, 3A, 4A, 5A is the A group; The device that is designated 1B, 2B, 3B, 4B, 5B is the B group; The device that is designated 1C, 2C, 3C, 4C, 5C is the C group; 5 kinds of devices of every group interconnect and constitute 3 cover separate signal treatment circuits; Be respectively A phase sequence signal processing circuit, B phase sequence signal processing circuit and C phase sequence signal processing circuit; The inner connection mode of 3 cover signal processing circuits is identical; Its inner connection mode is: the secondary side of voltage transformer (VT) (1A, 1B, 1C) is connected to the input of voltage channel wave filter (2A, 2B, 2C) as voltage channel wave filter (2A, 2B, 2C); The output of voltage channel wave filter (2A, 2B, 2C) is connected to the voltage channel input end of single-phase electricity parameter measurement chip (3A, 3B, 3C), and the secondary side of current transformer (5A, 5B, 5C) is connected to the input of current channel wave filter (4A, 4B, 4C) as current channel wave filter (4A, 4B, 4C), and the output of current channel wave filter (4A, 4B, 4C) is connected to the current channel input end of single-phase electricity parameter measurement chip (3A, 3B, 3C);
The primary side of 3 current transformers (5A, 5B, 5C) is that A phase sequence, B phase sequence, C phase sequence are connected to described each phase current connection terminal respectively by the phase sequence of signal processing circuit, and promptly the primary side of current transformer (5A) primary side that connects the sub-IA/IAN of current terminal, current transformer (5B) primary side that connects the sub-IB/IBN of current terminal, current transformer (5C) connects the sub-IC/ICN of current terminal;
The upper end of the primary side of A phase sequence voltage transformer (VT) (1A) connects the end of divider resistance RA, and the other end of divider resistance RA connects the sub-UA of voltage terminal, and the lower end of the primary side of A phase sequence voltage transformer (VT) (1A) connects the sub-UN of voltage terminal; The upper end of the primary side of B phase sequence voltage transformer (VT) (1B) connects the end of divider resistance RB; The other end of divider resistance RB connects the terminal X of mode of connection change-over switch (8), and the lower end of the primary side of B phase sequence voltage transformer (VT) (1B) connects the terminal Y of mode of connection change-over switch (8); The upper end of the primary side of C phase sequence voltage transformer (VT) (1C) connects the end of divider resistance RC, and the other end of divider resistance RC connects the sub-UC of voltage terminal, and the lower end of the primary side of C phase sequence voltage transformer (VT) (1C) connects the sub-UN of voltage terminal; The terminal SA of mode of connection change-over switch (8) connects the sub-UA of voltage terminal; The terminal SB of mode of connection change-over switch (8) connects the sub-UB of voltage terminal; The terminal SC of mode of connection change-over switch (8) connects the sub-UC of voltage terminal, and the terminal SN of mode of connection change-over switch (8) connects the sub-UN of voltage terminal;
3 single-phase electricity parameter measurement chips (3A, 3B, 3C) have single-phase electricity parameter measurement function; Can measure current effective value, voltage effective value, current instantaneous value, the instantaneous voltage of single-phase AC; Can accumulate the active energy in the short time, and these parameter values can be delivered to microcontroller MCU (9) through serial communication mode;
Logical communication link between the above-mentioned 3 cover signal processing circuits is: the measured parameter value of 3 single-phase electricity parameter measurement chips (3A, 3B, 3C) is read microcontroller MCU (9) respectively; Carry out comprehensive calculation process according to phase three-wire three or the determined mathematical relation of the three-phase and four-line mode of connection again, calculate three phase electrical parameters.
The term that above technical scheme is used, symbol and example do not constitute restriction to application of the present invention, just for the ease of explanation.
Claims (5)
1. phase three-wire three and three-phase and four-line compatible electrical parameter signal measurement and process system, system is sub by voltage terminal, current terminal, mode of connection change-over switch, divider resistance, signal processing circuit and microcontroller MCU form; Voltage terminal connects grid line outward, in connect mode for through being connected to voltage transformer (VT), voltage channel wave filter, single-phase electricity parameter measurement chip successively after the divider resistance parallel connection mode of connection change-over switch; Current terminal connects mode outward for by to being series at the electrical network phase line, in be linked as and be connected to current transformer, current channel wave filter, single-phase electricity parameter measurement chip successively; Voltage terminal and current terminal are by being connected to signal processing circuit in the path separately; The measured parameter value of signal processing circuit is read microcontroller MCU; Carry out comprehensive calculation process according to phase three-wire three or the determined mathematical relation of the three-phase and four-line mode of connection again; Calculate three phase electrical parameters, it is characterized in that:
Described voltage terminal has 4; Be UA, UB, UC and UN, UA, UB and UC are external in A, B, the C phase exit of the secondary side of electrical network A, B, three phase lines of C or instrument external voltage mutual inductor respectively; UN connects three-phase four-wire system electrical network center line, or connects three-phase three-wire system UB;
Described mode of connection change-over switch is a DPDT toggle switch with 6 connection terminals of SA, SB, SC, SN, X and Y; Its middle connecting terminal SA is connected with the sub-UA of voltage terminal; Connection terminal SB links to each other with the sub-UB of voltage terminal; Connection terminal SC is connected with the sub-UC of voltage terminal, and connection terminal SN is connected with the sub-UN of voltage terminal, also is connected with the lower end of the primary side of the lower end of the primary side of voltage transformer (VT) 1A and voltage transformer (VT) 1C; Connection terminal X is connected with divider resistance RB, and connection terminal Y is connected with the lower end of the primary side of voltage transformer (VT) 1B; When mode of connection change-over switch is upwards dialled; The closed conducting of connection terminal X and connection terminal SA, break off with connection terminal SB; The closed conducting of connection terminal Y and terminal SC, break off with connection terminal SN; When switch when setting aside, the closed conducting of connection terminal X and connection terminal SB, break off with connection terminal SA, connection terminal Y and the closed conducting of connection terminal SN, with connection terminal SC disconnection.
2. phase three-wire three according to claim 1 and three-phase and four-line compatible electrical parameter signal measurement and process system; It is characterized in that described current terminal has 6; Two a pair of; Be specially IA/IAR, IB/IBR, IC/ICR; IA/IAR be used to be connected in series electrical network A phase line or connect the secondary side exit of the current transformer on the outer A phase line of instrument, IB/IBR be used to be connected in series electrical network B phase line or connect the secondary side exit of the current transformer on the outer B phase line of instrument, IC/ICR be used to be connected in series electrical network C phase line or connect the secondary side exit of the current transformer on the outer C phase line of instrument.
3. phase three-wire three according to claim 1 and three-phase and four-line compatible electrical parameter signal measurement and process system; It is characterized in that described signal processing circuit; Contact successively by voltage transformer (VT), voltage channel wave filter, current transformer, current channel wave filter and single-phase electricity parameter measurement chip and to constitute; Have 3 cover separate signal treatment circuits in the native system; Wherein: voltage transformer (VT) is a two-port network, and its secondary side is connected to the input of voltage channel wave filter as the voltage channel wave filter, and the output of voltage channel wave filter is connected to the voltage channel input end of single-phase electricity parameter measurement chip; Current transformer is a two-port network, and its primary side is connected to each phase current connection terminal IA/IAN, IB/IBN, IC/ICN respectively by signal processing circuit, and secondary side is connected to the input of current channel wave filter as the current channel wave filter; The output of current channel wave filter is connected to the current channel input end of single-phase electricity parameter measurement chip; The end of divider resistance RA is connected with the sub-UA of voltage terminal, and the other end is connected with the upper end of the primary side of voltage transformer (VT) 1A; The end of divider resistance RB is connected with mode of connection change-over switch connection terminal X, the other end be connected with the upper end of the primary side of voltage transformer (VT) 1B; The end of divider resistance RC is connected with the sub-UC of voltage terminal, and the other end is connected with the upper end of the primary side of voltage transformer (VT) 1C.
4. phase three-wire three according to claim 1 and three-phase and four-line compatible electrical parameter signal measurement and process system; It is characterized in that described single-phase electricity parameter measurement chip; Has single-phase electricity parameter measurement function; Can measure current effective value, voltage effective value, current instantaneous value, the instantaneous voltage of single-phase AC, the active energy in the short time is accumulated, and these parameter values can be delivered to microcontroller MCU through serial communication mode.
5. phase three-wire three according to claim 3 and three-phase and four-line compatible electrical parameter signal measurement and process system; It is characterized in that the logical communication link between the described 3 cover signal processing circuits is: the measured parameter value of 3 single-phase electricity parameter measurement chips is read microcontroller MCU respectively; Carry out comprehensive calculation process according to phase three-wire three or the determined mathematical relation of the three-phase and four-line mode of connection again, calculate three phase electrical parameters.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010102085256A CN101893668B (en) | 2010-06-24 | 2010-06-24 | Three-phase three-wire and three-phase four-wire compatible electrical parameter signal measurement and process system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010102085256A CN101893668B (en) | 2010-06-24 | 2010-06-24 | Three-phase three-wire and three-phase four-wire compatible electrical parameter signal measurement and process system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101893668A CN101893668A (en) | 2010-11-24 |
| CN101893668B true CN101893668B (en) | 2012-07-25 |
Family
ID=43102920
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010102085256A Expired - Fee Related CN101893668B (en) | 2010-06-24 | 2010-06-24 | Three-phase three-wire and three-phase four-wire compatible electrical parameter signal measurement and process system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101893668B (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI430315B (en) * | 2010-12-02 | 2014-03-11 | Richwave Technology Corp | Double pole double throw swith device |
| CN103901269B (en) * | 2014-04-01 | 2017-09-22 | 江南大学 | It is easy to switch the electrical quantity measurement arrangement of the mode of connection |
| CN112147559A (en) * | 2019-06-26 | 2020-12-29 | 浙江共同电子科技有限公司 | Unified field calibration method based on three-phase three-wire electric energy meter and three-phase four-wire electric energy meter |
| CN112130069B (en) * | 2020-09-15 | 2022-12-23 | 江苏科技大学 | Main distribution board of generator |
| CN112327114B (en) * | 2020-10-30 | 2022-11-29 | 上海卫星装备研究所 | Heater resistance insulation measuring device suitable for spacecraft thermal test |
| CN114019202A (en) * | 2021-11-05 | 2022-02-08 | 国网江苏省电力有限公司营销服务中心 | Self-adaptive switching monitoring device and method for three-phase three-wire and three-phase four-wire mutual inductor |
| CN117192189B (en) * | 2023-11-03 | 2024-03-12 | 浙江正泰物联技术有限公司 | Three-phase voltage measurement circuit, method and three-phase ammeter |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2689236Y (en) * | 2004-04-12 | 2005-03-30 | 吴沛峰 | Three-phase and four-wire electronic idle and active assembled electric energy meter |
| DE102005036777B4 (en) * | 2005-08-02 | 2020-01-09 | Phoenix Contact Gmbh & Co. Kg | Three-phase power amplifier |
| EP2017867B1 (en) * | 2005-08-02 | 2010-09-15 | Phoenix Contact GmbH & Co. KG | Measuring device for measuring a periodic analogue signal |
| CN200956524Y (en) * | 2006-10-20 | 2007-10-03 | 朱金根 | Intelligent multi-path power supply switching controller |
| CN201262644Y (en) * | 2008-09-29 | 2009-06-24 | 山西省电力公司晋城供电分公司 | Synthesis device for examining watthour meter wire splice and calculating balance electricity quantity |
| CN201352235Y (en) * | 2009-05-18 | 2009-11-25 | 深圳市森晖电子有限公司 | Three-phase multifunctional electric energy meter |
-
2010
- 2010-06-24 CN CN2010102085256A patent/CN101893668B/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN101893668A (en) | 2010-11-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101893668B (en) | Three-phase three-wire and three-phase four-wire compatible electrical parameter signal measurement and process system | |
| CN201707415U (en) | Compatible type three-phase electrical parameter signal measuring processor | |
| CN104569527A (en) | Metering box used for low-voltage distributed type photovoltaic power generation | |
| CN204789669U (en) | Current sampling circuit | |
| CN210109188U (en) | Electric information sampling circuit | |
| CN109637792B (en) | Test transformer | |
| CN202930941U (en) | Electrical load imbalance intelligent compensation device | |
| CN207488346U (en) | Prevent the electric energy meter of improper electricity consumption | |
| CN203385805U (en) | Metalized power capacitor rapid aging testing device | |
| CN108776252B (en) | Metering secondary current loop of main transformer | |
| CN209184259U (en) | A kind of power distribution station three-level balance optimizing device | |
| CN210109189U (en) | Electric information monitoring device | |
| CN207603558U (en) | Exchange header box with smoke alarm unit | |
| CN209087542U (en) | Low voltage lead structure and distribution transformer | |
| CN207603557U (en) | Intelligent AC header box | |
| CN207069550U (en) | A kind of Digital Relay Protection Appliance | |
| CN215989852U (en) | Low-voltage distribution box | |
| CN101452061B (en) | UPS steady state test method | |
| CN202455087U (en) | Zero sequence compensator | |
| CN202854324U (en) | Capacitive load electric energy meter calibrating device | |
| CN108023357A (en) | A kind of new reactive power automatic compensation device | |
| CN105675973B (en) | Intelligent wireless insert row | |
| CN202815036U (en) | Intelligent segmented metering box | |
| CN216252533U (en) | System power supply circuit | |
| CN203553957U (en) | Device capable of balancing three-phase current |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C41 | Transfer of patent application or patent right or utility model | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20151228 Address after: Cangshan District of Fuzhou City, Fujian province 350008 Yang Qia halfway No. 8 Patentee after: Fujian Friendly Environment Technology Development Co.,Ltd. Address before: Minhou County of Fuzhou City, Fujian province 350108 streets of Fujian Normal University Qishan Campus University Department of science and technology Patentee before: Fujian Normal University |
|
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20120725 |