CN204287317U - A kind of three-phase intelligent ammeter with detection of electrical leakage - Google Patents
A kind of three-phase intelligent ammeter with detection of electrical leakage Download PDFInfo
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- CN204287317U CN204287317U CN201420769991.5U CN201420769991U CN204287317U CN 204287317 U CN204287317 U CN 204287317U CN 201420769991 U CN201420769991 U CN 201420769991U CN 204287317 U CN204287317 U CN 204287317U
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Abstract
The utility model discloses a kind of three-phase intelligent ammeter with detection of electrical leakage and comprise three-phase electric energy metering circuit, three-phase current Acquisition Circuit, three-phase voltage Acquisition Circuit, neutral line current Acquisition Circuit, microprocessor and warning circuit.Wherein the three-phase current collected and neutral line current data are transferred to microprocessor by the three-phase electrical energy computation chip of three-phase electric energy metering circuit, this microprocessor calculates three-phase combination phase current vector value according to three-phase current, again three-phase combination phase current vector value and neutral line current are carried out vector to subtract computing and draw total surplus electric current, again total surplus electric current and preset threshold value are compared, send whether alarm command according to comparative result; The alarm command that the warning circuit be electrically connected with microprocessor sends according to microprocessor performs warning.Whether therefore the utility model can detect in real time has leaky to occur, and reducing because electric leakage causes the accident of fire simultaneously, decreases the expense of electricity consumer.
Description
Technical field
The utility model relates to three-phase electric energy meter technical field, particularly relates to a kind of three-phase intelligent ammeter with detection of electrical leakage.
Background technology
Requirement according to electric fire monitoring system (GB14287): factory, retail shop, office building and high-rise residential building etc. easily occur because of the place causing fire failure of leaking electricity, and must install " residual current type detector for electric fire protection ".
Domestic adopted detector for electric fire protection is mostly a set of independently system at present, needs to buy separately.There is two problems in present settling mode: the first financial burden adding electric power users; During the second detector for electric fire protection work, need to be installed in supply line, and electric energy need be drawn from electrical network and carry out work, thus add the power consumption of user.
For above-mentioned technical matters, those skilled in the art are necessary to design a kind of electric energy meter self with earth leakage detection functions, while reduction causes fire failure because of electric leakage, also reduce the expense that user spends.
Utility model content
The purpose of this utility model is to provide a kind of three-phase intelligent ammeter with detection of electrical leakage, this intelligent electric meter itself has earth leakage detection functions, whether therefore the utility model can detect in real time has drain conditions to occur, and send warning in time when there being electric leakage, thus reduce the fire failure caused because of electric leakage, decrease the expense of electricity consumer.
For solving the problems of the technologies described above, the technical solution of the utility model is: a kind of three-phase intelligent ammeter with detection of electrical leakage comprises three-phase electric energy metering circuit, and described three-phase electric energy metering circuit comprises the three-phase electrical energy computation chip with neutral line current measurement function; Three-phase current Acquisition Circuit, the three-phase current of collection is transferred to described three-phase electrical energy computation chip by described three-phase current Acquisition Circuit; Three-phase voltage Acquisition Circuit, the three-phase voltage of collection is transferred to described three-phase electrical energy computation chip by described three-phase voltage Acquisition Circuit; Neutral line current Acquisition Circuit, the neutral line current of collection is transferred to described three-phase electrical energy computation chip by described neutral line current Acquisition Circuit; Microprocessor, described microprocessor is electrically connected with described three-phase electrical energy computation chip, and described three-phase electrical energy computation chip transmission three-phase current and neutral line current data give described microprocessor; Described microprocessor calculates three-phase combination phase current vector value according to the three-phase current data that described three-phase electrical energy computation chip transmits, more described three-phase combination phase current vector value and neutral line current are carried out vector ratio comparatively, sends whether alarm command according to comparative result; The warning circuit be electrically connected with described microprocessor, the alarm command that described warning circuit sends according to described microprocessor performs warning.
Optimal way is, described neutral line current Acquisition Circuit gathers neutral line current by manganese copper diverter.
Optimal way is, described microprocessor is electrically connected with fire plant by relay interface circuit.
Optimal way is, described warning circuit comprises sound alarm circuit.
Optimal way is, described warning circuit also comprises optical alarm circuit.
Optimal way is, described microprocessor is communicated with remote system by 485 serial communication protocols or carrier wave.
Optimal way is, described three-phase current Acquisition Circuit gathers each phase current by dividing the current transformer being located at three-phase.
Optimal way is, described three-phase voltage Acquisition Circuit gathers each phase voltage by dividing the resistor voltage divider circuit being located at three-phase.
Optimal way is, described three-phase electrical energy computation chip selects RN8302 chip.
After adopting technique scheme, the beneficial effects of the utility model are: because the three-phase intelligent ammeter with detection of electrical leakage of the present utility model comprises three-phase electric energy metering circuit, this three-phase electric energy metering circuit comprises the three-phase electrical energy computation chip with neutral line current measurement function.The utility model also comprises the three-phase current Acquisition Circuit, three-phase voltage Acquisition Circuit and the neutral line current Acquisition Circuit that are electrically connected with three-phase electrical energy computation chip, and three-phase electrical energy computation chip is also electrically connected with microprocessor simultaneously.This microprocessor calculates three-phase combination phase current vector value according to the three-phase current data that three-phase electrical energy computation chip transmits, then three-phase combination phase current vector value and neutral line current are carried out vector subtracts computing and draw total surplus electric current; Then the effective value of total surplus current value and preset residual current threshold value are compared, if total surplus circuit flow valuve is less than setting threshold value, without the need to reporting to the police, if be greater than threshold range, microprocessor sends alarm command.When leakage current reaches the threshold value of setting, microprocessor sends alarm command and passes to warning circuit, this warning circuit performs alarm command, notifies that this electric energy meter user has leaky to occur by alarm command, thus avoids because leaking electricity unmanned process that breaking out of fire is dangerous.And the self-contained earth leakage detection functions of the utility model, without the need to additional equipment, thus decrease the expense of electricity consumption user.
Because microprocessor is electrically connected with fire plant by relay interface circuit, this structure makes to touch fire plant during generation leaky, reaches the object of reporting to the police to fire fighter.
Because warning circuit comprises sound alarm circuit, hummer time this structure makes generation leaky in electric energy meter yowls, from acoustically reporting to the police.
Because warning circuit also comprises optical alarm circuit, time this structure makes generation leaky, backlight Chang Liang in electric energy meter, visually reports to the police.
Because microprocessor is communicated with remote system by 485 serial communication protocols or carrier wave; This structure makes detection of electrical leakage of the present utility model be uploaded to remote system, is convenient to Systematical control.
Because three-phase electrical energy computation chip selects RN8302 chip, the self-contained neutral line current measurement function of this computation chip.
In sum, whether the three-phase intelligent ammeter with detection of electrical leakage of the present utility model can detect in real time has leaky to occur, and can by sound and light and alarm, can also send alerting signal by fire plant, therefore the utility model can reduce the fire hazard caused because of the electric leakage of electric energy meter user power circuit greatly; Again because the utility model self has leakage current test function, thus reduce the expense of electricity consumption user.
Accompanying drawing explanation
Fig. 1 is the theory diagram of the three-phase intelligent ammeter with detection of electrical leakage of the present utility model;
Fig. 2 is the circuit diagram of the relay interface circuit of Fig. 1;
Fig. 3 is the circuit diagram of three-phase current Acquisition Circuit in Fig. 1 and neutral line current Acquisition Circuit;
Fig. 4 is the circuit diagram of the three-phase voltage Acquisition Circuit in Fig. 1;
Fig. 5 is the circuit diagram of the sound alarm circuit in Fig. 1;
Fig. 6 is the circuit diagram of the optical alarm circuit in Fig. 1.
Embodiment
In order to make the purpose of this utility model, technical scheme and advantage clearly understand, below in conjunction with drawings and Examples, the utility model is further elaborated.Should be appreciated that specific embodiment described herein only in order to explain the utility model, and be not used in restriction the utility model.
As shown in Figure 1, a kind of three-phase intelligent ammeter with detection of electrical leakage comprises three-phase electric energy metering circuit, and this three-phase electric energy metering circuit comprises the three-phase electrical energy computation chip with neutral line current measurement function, preferred RN8302 chip.This three-phase electrical energy computation chip also respectively with three-phase current Acquisition Circuit, three-phase voltage Acquisition Circuit and neutral line current Acquisition Circuit electrical connection; Above-mentioned electrical connection is specially: the three-phase current of collection is transferred to three-phase electrical energy computation chip by three-phase current Acquisition Circuit, the three-phase voltage of collection is transferred to three-phase electrical energy computation chip by three-phase voltage Acquisition Circuit, and the neutral line current of collection is transferred to three-phase electrical energy computation chip by neutral line current Acquisition Circuit.Then three-phase electrical energy computation chip measures all parameters of three-phase intelligent ammeter by self function, and the parameters such as such as three-phase electric energy, therefore the utility model maintains the script function of three-phase intelligent ammeter.Three-phase electrical energy computation chip is also electrically connected with microprocessor in addition, and this electrical connection is specially: three-phase electrical energy computation chip is transferred to microprocessor by after the three-phase current collected and the process of neutral line current value, the preferred single-chip microcomputer of microprocessor of the present embodiment.
The three-phase electricity flow valuve that this microprocessor can transmit according to three-phase electrical energy computation chip calculates three-phase combination phase current, and this three-phase combination phase current is vector.Then the three-phase combination phase current calculated and neutral line current are carried out vector and subtract computing and draw total surplus electric current by microprocessor again, and total surplus electric current specifically refers to three-phase current and the total residual electricity flow valuve of neutral line current; Then judge whether the effective value of total surplus current value exceedes the residual current alarm threshold value pre-set, residual current threshold value setting range of the present utility model is: effective value-20mA to 1000mA.If total surplus current effective value is less than setting threshold value, then electric energy meter does not detect that leakage phenomenon occurs; If be greater than setting threshold value, then show that electric energy meter has detected that leaky occurs; So microprocessor output alarm instruction, and alarm command is transferred to warning circuit.And warning circuit alarm command is changed into the concrete form such as sound, light to express electric energy meter electric leakage the fact, to notify personnel to process, thus reach prevent because electric energy meter electric leakage and the danger of breaking out of fire occur.Self-contained earth leakage detection functions of the present utility model in addition, makes user without the need to being equipped with equipment in addition, thus reduces the expense of electricity consumption user.
As shown in Figure 3, the three-phase current Acquisition Circuit of the present embodiment is gathered by three current transformers, the CTA1 end and the CTA2 termination that wherein gather current transformer circuit from figure of A phase current enter, and then A phase current enters RN8302 chip from I1P end and I1N termination; The CTB1 end and the CTB2 termination that wherein gather current transformer circuit from figure of B phase current enter, and then B phase current enters RN8302 chip from I2P end and I2N termination; The CTC1 end and the CTC2 termination that wherein gather current transformer circuit from figure of C phase current enter, and then C phase current enters RN8302 chip from I3P end and I3N termination.
As shown in Figure 4, the three-phase voltage Acquisition Circuit of the present embodiment is gathered by three groups of resistor voltage divider circuits, and wherein A phase voltage is from the UA end input of circuit, and then A phase voltage VA end and VAN termination from circuit enters RN8302 chip; Wherein B phase voltage is from the UB end input of circuit, and then B phase voltage enters RN8302 chip from the VB end circuit and VBN termination; Wherein C phase voltage is from the UC end input of circuit, and then C phase voltage enters RN8302 chip from the VC end circuit and VCN termination.The electric energy meter of the present embodiment is three-phase four-wire system in addition, notes neutral voltage UN during wiring.
As shown in Figure 3, the neutral line current Acquisition Circuit of the present embodiment is gathered by manganese copper diverter, and the IN1 end of this manganese copper diverter circuit from figure and IN2 termination enter, and then neutral line current enters RN8302 chip from INP end and INN termination.
As shown in Figure 2, the microprocessor of the present embodiment is electrically connected with fire plant by relay interface circuit, and this electrical connection is specially: the control coil of relay G5NB-1A-E is electrically connected with microprocessor.Microprocessor, by the disconnection of pilot relay, indirectly controls fire plant and starts, thus utilize fire plant to reach the object of warning, and namely the utility model prevents the fire caused because of electric leakage to occur further, adds the security of electricity consumption.
As shown in Figure 5, the warning circuit of the present embodiment comprises sound alarm circuit, and namely sound alarm circuit is electrically connected with microprocessor, and performs warning according to the alarm command that microprocessor sends.Above-mentioned electrical connection is specially: the FMQ end in sound alarm circuit is electrically connected with microprocessor, microprocessor is held by FMQ and is performed warning electric signal to sound alarm circuit input, hummer is made to continue sounding, thus make the utility model when electric leakage occurs electric energy meter, can from the object acoustically reaching warning.
As shown in Figure 6, the warning circuit of the present embodiment also comprises optical alarm circuit, and namely optical alarm circuit is electrically connected with microprocessor, and performs warning according to the alarm command that microprocessor sends.Above-mentioned electrical connection is specially: the BAKLED end in optical alarm circuit is electrically connected with microprocessor, microprocessor is held by BAKLED and is performed warning electric signal to optical alarm circuit input, make the LED continuous illumination be located in electric energy meter, thus make the utility model when electric energy meter generation leaky, visually can reach the object of warning.
As shown in Figure 1, the microprocessor of the present embodiment is also communicated with remote system by 485 serial communication protocols or carrier communication, be specially: by 485 serial communication protocols or carrier communication, the correlation parameter of electric energy meter and detection of electrical leakage information are uploaded to remote system, be convenient to remote system control and management, further increase the security of electricity consumption.
After the utility model is come into operation, the utility model can detect neutral line current value in real time, and every electric current and neutral line current data are transferred to microprocessor, this microprocessor, by after the calculating of data, comparing and judge, show whether the utility model detects that leaky occurs.If there is leaky to occur, microprocessor is to the instruction of warning circuit output alarm, warning circuit is made to perform alarm command in many ways, namely give notice in many ways and the signal that gives the alarm, can be keeped in repair in the very first time after making electric energy meter electric leakage be detected, thus be avoided the fire hazard caused because of subscriber's line circuit electric leakage.Simultaneously because the utility model itself has earth leakage detection functions, make user also can ensure Electrical Safety without the need to optional equipment equipment, thus decrease the expense of electricity consumption user.
The invention, on the basis realizing traditional three-phase intelligent ammeter Electro-metering and other electricity consumption data monitorings, adds circuit residual current monitoring function, realizes detection of electrical leakage, and be connected directly to existing fire plant by warning output interface
The above preferred embodiment of the present utility model; not in order to limit the utility model; all do within spirit of the present utility model and principle any amendment, etc. same with the improvement etc. of the three-phase intelligent ammeter structure of detection of electrical leakage, all should be included within protection domain of the present utility model.
Claims (9)
1. with a three-phase intelligent ammeter for detection of electrical leakage, it is characterized in that, comprise
Three-phase electric energy metering circuit, described three-phase electric energy metering circuit comprises the three-phase electrical energy computation chip with neutral line current measurement function;
Three-phase current Acquisition Circuit, the three-phase current of collection is transferred to described three-phase electrical energy computation chip by described three-phase current Acquisition Circuit;
Three-phase voltage Acquisition Circuit, the three-phase voltage of collection is transferred to described three-phase electrical energy computation chip by described three-phase voltage Acquisition Circuit;
Neutral line current Acquisition Circuit, the neutral line current of collection is transferred to described three-phase electrical energy computation chip by described neutral line current Acquisition Circuit;
Microprocessor, described microprocessor is electrically connected with described three-phase electrical energy computation chip, and described three-phase electrical energy computation chip transmission three-phase current and neutral line current data give described microprocessor; Described microprocessor calculates three-phase combination phase current vector value according to the three-phase current data that described three-phase electrical energy computation chip transmits, more described three-phase combination phase current vector value and neutral line current are carried out vector ratio comparatively, sends whether alarm command according to comparative result;
The warning circuit be electrically connected with described microprocessor, the alarm command that described warning circuit sends according to described microprocessor performs warning.
2. the three-phase intelligent ammeter with detection of electrical leakage according to claim 1, is characterized in that, described neutral line current Acquisition Circuit gathers neutral line current by manganese copper diverter.
3. the three-phase intelligent ammeter with detection of electrical leakage according to claim 1 and 2, is characterized in that, described microprocessor is electrically connected with fire plant by relay interface circuit.
4. the three-phase intelligent ammeter with detection of electrical leakage according to claim 3, is characterized in that, described warning circuit comprises sound alarm circuit.
5. the three-phase intelligent ammeter with detection of electrical leakage according to claim 4, is characterized in that, described warning circuit also comprises optical alarm circuit.
6. the three-phase intelligent ammeter with detection of electrical leakage according to claim 5, is characterized in that, described microprocessor is communicated with remote system by 485 serial communication protocols or carrier wave.
7. the three-phase intelligent ammeter with detection of electrical leakage according to claim 6, is characterized in that, described three-phase current Acquisition Circuit gathers each phase current by dividing the current transformer being located at three-phase.
8. the three-phase intelligent ammeter with detection of electrical leakage according to claim 7, is characterized in that, described three-phase voltage Acquisition Circuit gathers each phase voltage by dividing the resistor voltage divider circuit being located at three-phase.
9. the three-phase intelligent ammeter with detection of electrical leakage according to claim 8, is characterized in that, described three-phase electrical energy computation chip selects RN8302 chip.
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Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN105931412A (en) * | 2016-07-11 | 2016-09-07 | 安徽升隆电气有限公司 | Intelligent residual current type fire detecting monitor |
| CN107843799A (en) * | 2017-09-22 | 2018-03-27 | 国网浙江省电力公司丽水供电公司 | A kind of low pressure residue leakage current measurement instrument and its method of work |
| CN108037333A (en) * | 2015-11-27 | 2018-05-15 | 浙江八达电子仪表有限公司 | The adjustable three-phase intelligent electric-energy meter of residual current threshold value |
| CN108181502A (en) * | 2017-12-27 | 2018-06-19 | 上海贝岭股份有限公司 | Electric energy computation chip and electric energy metering device |
| CN109030935A (en) * | 2018-08-10 | 2018-12-18 | 国网湖南省电力有限公司 | A kind of three-phase and four-line intelligent meter of independent measurement neutral line current |
| CN109164345A (en) * | 2018-09-27 | 2019-01-08 | 深圳友讯达科技股份有限公司 | Live line Zero line Wiring detection method, device and intelligent electric meter |
| CN109946553A (en) * | 2017-12-21 | 2019-06-28 | 成都长城开发科技有限公司 | Three-phase kilowatt-hour meter and its earth-fault detecting method |
| CN111090001A (en) * | 2019-10-21 | 2020-05-01 | 浙江恒业电子有限公司 | Residual current testing system and method |
| CN112114272A (en) * | 2020-08-17 | 2020-12-22 | 宁波三星医疗电气股份有限公司 | Leakage current detection system and leakage current detection method for electric energy meter |
| CN112462296A (en) * | 2020-11-05 | 2021-03-09 | 广东电网有限责任公司阳江供电局 | Be applied to electrified alarm device at power consumption monitor terminal |
| CN113721070A (en) * | 2020-05-26 | 2021-11-30 | 天津首瑞智能电气有限公司 | Residual current detection device and residual current detection method |
| CN113834969A (en) * | 2021-08-12 | 2021-12-24 | 国网浙江省电力有限公司营销服务中心 | Direct access type direct current electric energy meter |
| CN114062772A (en) * | 2020-08-07 | 2022-02-18 | 天津首瑞智能电气有限公司 | Residual current measuring circuit |
| CN114280499A (en) * | 2021-12-21 | 2022-04-05 | 国能榆林能源有限责任公司 | Electric leakage detection method for coal mine underground power supply system and coal mine underground power supply system |
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| CN108037333A (en) * | 2015-11-27 | 2018-05-15 | 浙江八达电子仪表有限公司 | The adjustable three-phase intelligent electric-energy meter of residual current threshold value |
| CN108254599A (en) * | 2015-11-27 | 2018-07-06 | 浙江八达电子仪表有限公司 | Acquire the three-phase intelligent electric-energy meter structure of residual current |
| CN105931412A (en) * | 2016-07-11 | 2016-09-07 | 安徽升隆电气有限公司 | Intelligent residual current type fire detecting monitor |
| CN107843799A (en) * | 2017-09-22 | 2018-03-27 | 国网浙江省电力公司丽水供电公司 | A kind of low pressure residue leakage current measurement instrument and its method of work |
| CN109946553B (en) * | 2017-12-21 | 2021-06-22 | 成都长城开发科技有限公司 | Three-phase electric meter and ground fault detection method thereof |
| CN109946553A (en) * | 2017-12-21 | 2019-06-28 | 成都长城开发科技有限公司 | Three-phase kilowatt-hour meter and its earth-fault detecting method |
| CN108181502A (en) * | 2017-12-27 | 2018-06-19 | 上海贝岭股份有限公司 | Electric energy computation chip and electric energy metering device |
| CN109030935A (en) * | 2018-08-10 | 2018-12-18 | 国网湖南省电力有限公司 | A kind of three-phase and four-line intelligent meter of independent measurement neutral line current |
| CN109164345A (en) * | 2018-09-27 | 2019-01-08 | 深圳友讯达科技股份有限公司 | Live line Zero line Wiring detection method, device and intelligent electric meter |
| CN111090001A (en) * | 2019-10-21 | 2020-05-01 | 浙江恒业电子有限公司 | Residual current testing system and method |
| CN113721070A (en) * | 2020-05-26 | 2021-11-30 | 天津首瑞智能电气有限公司 | Residual current detection device and residual current detection method |
| CN113721070B (en) * | 2020-05-26 | 2024-03-29 | 天津首瑞智能电气有限公司 | Residual current detection device and residual current detection method |
| CN114062772A (en) * | 2020-08-07 | 2022-02-18 | 天津首瑞智能电气有限公司 | Residual current measuring circuit |
| CN112114272A (en) * | 2020-08-17 | 2020-12-22 | 宁波三星医疗电气股份有限公司 | Leakage current detection system and leakage current detection method for electric energy meter |
| CN112462296A (en) * | 2020-11-05 | 2021-03-09 | 广东电网有限责任公司阳江供电局 | Be applied to electrified alarm device at power consumption monitor terminal |
| CN113834969A (en) * | 2021-08-12 | 2021-12-24 | 国网浙江省电力有限公司营销服务中心 | Direct access type direct current electric energy meter |
| CN114280499A (en) * | 2021-12-21 | 2022-04-05 | 国能榆林能源有限责任公司 | Electric leakage detection method for coal mine underground power supply system and coal mine underground power supply system |
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