CN204536414U - A kind of low-voltage network residual current monitoring system - Google Patents

A kind of low-voltage network residual current monitoring system Download PDF

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Publication number
CN204536414U
CN204536414U CN201520181326.9U CN201520181326U CN204536414U CN 204536414 U CN204536414 U CN 204536414U CN 201520181326 U CN201520181326 U CN 201520181326U CN 204536414 U CN204536414 U CN 204536414U
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China
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module
residual current
electrically
signal
electric energy
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CN201520181326.9U
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戚星宇
严永辉
黄申茂
庄壬
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State Grid Corp of China SGCC
State Grid Jiangsu Electric Power Co Ltd
Changzhou Power Supply Co of Jiangsu Electric Power Co
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State Grid Corp of China SGCC
State Grid Jiangsu Electric Power Co Ltd
Changzhou Power Supply Co of Jiangsu Electric Power Co
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Priority to CN201520181326.9U priority Critical patent/CN204536414U/en
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Abstract

The utility model provides a kind of low-voltage network residual current monitoring system, comprises and can measure residual current electric energy meter, backstage monitor server and communication channel; The user side that the distribution of residual current electric energy meter is arranged at low-voltage network can be measured, respectively can measure residual current electric energy meter and be electrically connected with backstage monitor server two-way signaling by communication channel; Communication channel adopts RS485 bus or power line carrier communication channel; Residual current electric energy meter can be measured and comprise housing, terminal block, phase line, zero line, relay, phase line current sampling resistor, residual current transformer and circuit arrangement.The utility model structure is simple, cost-saving, easy for installation, safe and reliable, be easy to spread, the residual current with early warning user effectively can be monitored during use, remote controlled cut-out user electric current is with the generation of the malignant events such as fire preventing if desired, ensures power supply safety.

Description

A kind of low-voltage network residual current monitoring system
Technical field
The utility model relates to field of distribution network, is specifically related to a kind of low-voltage network residual current monitoring system based on measuring residual current electric energy meter.
Background technology
At society, electric power has become the most important energy of the mankind.Along with the fast development of China's economy, electric energy plays more and more important effect in economic construction and daily life.But while electric energy benefits people's life, electrical fire also occurs in a large number, causes huge loss thereupon.China public security fire-fighting office investigation 1996 up to more than 26 ten thousand, accounts for 23.9% of fire sum to the electrical fire in 2005.In electrical fire, have and caused by residual current greatly.Meanwhile, residual current also may cause the accidents such as the person electric shock, device damage.For this reason, the common practice of countries in the world is in low voltage electric network, install RCD (RCD).But residual current operated protective device can only carry out trip protection when residual current transfinites, early warning and Real-Time Monitoring cannot be carried out.In addition, the misoperation of residual current operated protective device is the thing that power supply department and user are puzzled always, and this has not only had a strong impact on the result of use of protector, also directly affects the reliability of power supply.Cause the reason of RCD misoperation to be complicated and diversified, these faults need staff to investigate from door to door to scene, the manpower and materials of at substantial, and efficiency is very low.
Utility model content
The purpose of this utility model is: the low-voltage network residual current monitoring system providing a kind of structure simple, cost-saving, easy for installation, safe and reliable, when it uses, effectively can solve the Real-Time Monitoring problem of user side residual current in low-voltage network, ensure power supply safety.
The technical solution of the utility model is: low-voltage network residual current monitoring system of the present utility model, and its design feature is: comprise and can measure residual current electric energy meter, backstage monitor server and communication channel;
The user side that the distribution of residual current electric energy meter is arranged at low-voltage network can be measured; Respectively can measure residual current electric energy meter to be electrically connected with backstage monitor server two-way signaling by communication channel;
The above-mentioned residual current measured electric energy meter comprises housing, terminal block, relay, phase line current sampling resistor, phase line, zero line, residual current transformer and circuit arrangement; Terminal block comprises the first connection terminal, the second connection terminal, the 3rd connection terminal and the 4th connection terminal; Terminal block is fixedly mounted on housing; Relay, phase line current sampling resistor, phase line, zero line and residual current transformer are all arranged in housing; One end of zero line is electrically connected with the 3rd connection terminal; The other end of zero line is electrically connected with the 4th connection terminal; One end of phase line current sampling resistor is electrically connected with the first connection terminal; The other end of phase line current sampling resistor is electrically connected with relay; One end of phase line is electrically connected with the second connection terminal; The other end of phase line is electrically connected with relay; Residual current transformer is arranged at phase line with zero line mutually near place, and phase line and zero line are through residual current transformer; Circuit arrangement is electrically connected respectively with relay, phase line current sampling resistor and residual current transformer.
Further scheme is: above-mentioned communication channel is RS485 bus.
Further scheme is: above-mentioned communication channel is voltage Power Line Carrier Channel.
Further scheme also has: the circuit arrangement of the above-mentioned residual current measured electric energy meter comprises voltage sample module, signal processing module, A/D modular converter, electric energy metering module, single chip processing module, relay control module, communication module, LCD display module, key-press module and power module;
Voltage sample module, signal processing module, A/D modular converter, electric energy metering module, single chip processing module, relay control module, communication module and power module are arranged in housing;
Voltage sample module is provided with signal output part; Signal processing module is provided with voltage sampling signal input end, phase line current sampled signal input end, residual current signal input part and signal output part; A/D modular converter is provided with signal input part, the first signal output part and secondary signal output terminal; Electric energy metering module is provided with signal input part and signal output part; Single chip processing module is provided with sampled signal input end, power consumption signal input end, relay control signal output terminal, communication ends, display output terminal and push button signalling input end; Relay control module is provided with signal input part and control signal output terminal; Communication module is provided with internal communication ends and correspondence with foreign country end; LCD display module is provided with signal input part; Key-press module is provided with signal output part;
The voltage sampling signal input end of signal processing module, phase line current sampled signal input end and residual current signal input part are respectively with signal output part, the phase line current sampling resistor of voltage sample module with residual current transformer is corresponding is electrically connected; The signal input part of A/D modular converter is electrically connected with the signal output part of signal processing module; The signal input part of electric energy metering module is electrically connected with the first signal output part signal of A/D modular converter; The sampled signal input end of single chip processing module is electrically connected with the secondary signal output end signal of A/D modular converter; The power consumption signal input end of single chip processing module is electrically connected with electric energy metering module signal output part signal; The signal input part of relay control module is electrically connected with the relay control signal output end signal of single chip processing module; The control signal output terminal of relay control module is electrically connected with the control end of relay; The internal communication ends of communication module is electrically connected with the communication ends two-way signaling of single chip processing module; The correspondence with foreign country end of communication module is electrically connected with above-mentioned communication channel signal; The signal input part of LCD display module is electrically connected with the display output end signal of single chip processing module; The signal output part of key-press module is electrically connected with the push button signalling input end signal of single chip processing module; Power module provides working power.
The utility model has positive effect: (1) low-voltage network residual current of the present utility model monitoring system, form by being distributed in the residual current the measured electric energy meter of user side, communication channel and backstage monitor server, structure is simple, cost-saving, easy for installation, safe and reliable, is easy to spread.(2) low-voltage network residual current monitoring system of the present utility model, its communication channel can adopt RS485 bus or voltage Power Line Carrier Channel, and it is convenient to realize, and cost is lower.(3) low-voltage network residual current monitoring system of the present utility model, it in use, realize carrying out Real-Time Monitoring, record to the residual current of the user side in low-voltage distributing line by residual current electric energy meter can be measured, the residual current event of transfiniting exceeding preset alarming threshold value is reported to the police; Residual current measurement data and the record of all user sides upload to backstage monitor server by RS485 bus or voltage Power Line Carrier Channel, statistical study is carried out by the residual current event of backstage monitor server to all user sides, and finally early warning is carried out to the residual current event of user side, thus can prevent trouble before it happens, user's electric current is cut off in the remote controlled actuating of relay of measuring in residual current electric energy meter of backstage monitor server if desired, with the generation of the malignant events such as fire preventing, ensure power supply safety.
Accompanying drawing explanation
Fig. 1 is structural representation of the present utility model;
Fig. 2 is the structural representation can measuring residual current electric energy meter in Fig. 1, and figure middle shell eliminates protecgulum and do not draw;
Fig. 3 is the circuit structure schematic block diagram can measuring residual current electric energy meter in Fig. 1.
Reference numeral in above-mentioned accompanying drawing is as follows:
Residual current electric energy meter 101 can be measured, housing 1, terminal block 2, the first connection terminal 21, second connection terminal 22,3rd connection terminal the 23, four connection terminal 24, relay 3, phase line current sampling resistor 4, phase line 5, zero line 6, residual current transformer 7, circuit arrangement 8;
Backstage monitor server 102,
Communication channel 103.
Embodiment
Below in conjunction with the drawings and specific embodiments, the utility model is described in further detail.
(embodiment)
See Fig. 1 to Fig. 3, the low-voltage network residual current monitoring system of the present embodiment, form primarily of residual current electric energy meter 101, backstage monitor server 102 and communication channel 103 can be measured.
The user side that residual current electric energy meter 101 distribution is arranged at low-voltage network can be measured; Respectively can measure residual current electric energy meter 101 to be electrically connected with backstage monitor server 102 two-way signaling by communication channel 103.
Residual current electric energy meter 101 can be measured form primarily of housing 1, terminal block 2, relay 3, phase line current sampling resistor 4, phase line 5, zero line 6, residual current transformer 7 and circuit arrangement 8.
Relay 3 is fixedly installed in housing 1.In the present embodiment, relay 3 preferably adopts JML82 type magnetic latching relay.
Phase line current sampling resistor 4 is arranged in housing 1.Preferably copper-manganese sampling resistor is adopted in phase line current sampling resistor 4 the present embodiment.One end of phase line current sampling resistor 4 is electrically connected with the first connection terminal 21; The other end of phase line current sampling resistor 4 is electrically connected with relay 3.
Phase line 5, zero line 6 and residual current transformer 7 are all arranged in housing 1.
One end of phase line 5 is electrically connected with the second connection terminal 22; The other end of phase line 5 is electrically connected with relay 3.
One end of zero line 6 is electrically connected with the 3rd connection terminal 23; The other end of zero line 6 is electrically connected with the 4th connection terminal 24.Zero line 6 is mutually close with phase line 5 in housing 1, and zero line 6 is bent into square shape with phase line 5 near place, for guaranteeing that residual current transformer 7 can residual current in correct sample user circuit when the normal wiring of ammeter.
Residual current transformer 7 is arranged at phase line 5 with zero line 6 mutually near place, and phase line 5 and zero line 6 are through residual current transformer 7.In the present embodiment, residual current transformer 7 preferably adopts HLTY1 type current transformer.
Circuit arrangement 8 forms primarily of voltage sample module 81, signal processing module 82, A/D modular converter 83, electric energy metering module 84, single chip processing module 85, relay control module 86, communication module 87, LCD display module 88, key-press module 89 and power module 80.
The voltage sample module 81 of circuit arrangement 8, signal processing module 82, A/D modular converter 83, electric energy metering module 84, single chip processing module 85, relay control module 86, communication module 87 and power module 80 are arranged in housing 1.
Voltage sample module 81 is provided with signal output part; Signal processing module 82 is provided with voltage sampling signal input end, phase line current sampled signal input end, residual current signal input part and signal output part; A/D modular converter 83 is provided with signal input part, the first signal output part and secondary signal output terminal; Electric energy metering module 84 is provided with signal input part and signal output part; Single chip processing module 85 is provided with sampled signal input end, power consumption signal input end, relay control signal output terminal, communication ends, display output terminal and push button signalling input end; Relay control module 86 is provided with signal input part and control signal output terminal; Communication module 87 is provided with internal communication ends and correspondence with foreign country end; LCD display module 88 is provided with signal input part; Key-press module 89 is provided with signal output part.
The voltage sampling signal input end of signal processing module 82, phase line current sampled signal input end and residual current signal input part are respectively with signal output part, the phase line current sampling resistor 4 of voltage sample module 81 with residual current transformer 7 is corresponding is electrically connected; The signal input part of A/D modular converter 83 is electrically connected with the signal output part of signal processing module 82; The signal input part of electric energy metering module 84 is electrically connected with the first signal output part signal of A/D modular converter 83; The sampled signal input end of single chip processing module 85 is electrically connected with the secondary signal output end signal of A/D modular converter 83; The power consumption signal input end of single chip processing module 85 is electrically connected with electric energy metering module 84 signal output part signal; The signal input part of relay control module 86 is electrically connected with the relay control signal output end signal of single chip processing module 85; The control signal output terminal of relay control module 86 is electrically connected with the control end of relay 3; The internal communication ends of communication module 87 is electrically connected with the communication ends two-way signaling of single chip processing module 85; With monitoring background communication when the correspondence with foreign country end of communication module 87 uses; The signal input part of LCD display module 88 is electrically connected with the display output end signal of single chip processing module 85; The signal output part of key-press module 89 is electrically connected with the push button signalling input end signal of single chip processing module 85; Power module 80 provides working power for electric energy meter.
The LCD display module 88 of circuit arrangement 8 comprises the LCD display be arranged on housing 1; Key-press module 89 comprises the button be arranged on housing 1.The display of the warning message when LCD display of LCD display module 88 transfinites for the power consumption and residual current showing user during normal work.Button on key-press module 89 is used for power consumer and consults the mutual of power consumption information etc. and electric energy meter.
In communication module 87 the present embodiment, preferably include infrared communication interface, RS485 communication interface and carrier communication interface.Infrared communication interface, RS485 communication interface and carrier communication interface are respectively equipped with internal communication ends and correspondence with foreign country end; The internal communication ends of infrared communication interface, RS485 communication interface and carrier communication interface forms the internal communication ends of aforesaid communication module 87 jointly; The correspondence with foreign country end of infrared communication interface, RS485 communication interface and carrier communication interface forms the correspondence with foreign country end of aforesaid communication module 87 jointly.The infrared communication interface of communication module 87 is used for the on-the-spot parameters of staff and reads data in table.RS485 communication interface and carrier communication interface are mainly used in the monitoring background communication with power supply department.
Residual current electric energy meter 101 can be measured and phase line current loop is made up of phase line current sampling resistor 4, relay 3 and phase line 5; Phase line current flows into from the first connection terminal 21 of terminal block 2, the second connection terminal 22 flows out; Phase line current signal obtains by phase line current sampling resistor 4; Neutral line current loop is made up of zero line 6, and neutral line current flows into from the 4th connection terminal 24 of terminal block 2, and the 3rd connection terminal 23 flows out; Residual current signal is obtained by residual current sampling mutual inductor 7.
(application examples)
The low-voltage network residual current monitoring system of previous embodiment, it in use, when the residual current the measured electric energy meter 101 being divided into each user side of low-voltage network works, its phase line current sampled signal, residual current sampled signal deliver to circuit arrangement 8, wherein phase line current signal is used for real time electrical quantity calculating, residual current sampled signal is used for carrying out Real-Time Monitoring to the residual electricity flow valuve of subscriber's line, and timing carries out record to the residual electricity flow valuve in low-voltage distributing line.Once the residual electricity flow valuve in discovery subscriber's line exceedes preset alarming threshold value, electric energy meter is at once to User Alarms, form residual current overload alarm logout, and in time by communication channel 103(RS485 bus or voltage Power Line Carrier Channel) notify backstage monitor server 102.Backstage monitor server 102 reads residual current record and the overload alarm event of the residual current the measured electric energy meter 101 of user side by RS485 bus or voltage Power Line Carrier Channel, and statistical study is carried out to residual current overload alarm event, residual current contingent in subscriber's line circuit is transfinited and predicts, and residual current electric energy meter 101 can be measured by communication channel 103 to this user and send information, residual current electric energy meter 101 can be measured given warning in advance to user by this.If desired, remote controlled relay 3 action of measuring in residual current electric energy meter 101 of backstage monitor server 102, cuts off user's electric current, with the generation of the malignant events such as fire preventing.
Above embodiment and application examples are the explanations to embodiment of the present utility model; but not to restriction of the present utility model; person skilled in the relevant technique is not when departing from spirit and scope of the present utility model; can also make various conversion and change and obtain corresponding equivalent technical scheme, therefore all equivalent technical schemes all should be included into scope of patent protection of the present utility model.

Claims (4)

1. a low-voltage network residual current monitoring system, is characterized in that: comprise and can measure residual current electric energy meter (101), backstage monitor server (102) and communication channel (103);
The user side that residual current electric energy meter (101) distribution is arranged at low-voltage network can be measured; Respectively can measure residual current electric energy meter (101) to be electrically connected with backstage monitor server (102) two-way signaling by communication channel (103);
The described residual current measured electric energy meter (101) comprises housing (1), terminal block (2), relay (3), phase line current sampling resistor (4), phase line (5), zero line (6), residual current transformer (7) and circuit arrangement (8); Terminal block (2) comprises the first connection terminal (21), the second connection terminal (22), the 3rd connection terminal (23) and the 4th connection terminal (24); Terminal block (2) is fixedly mounted on housing (1); Relay (3), phase line current sampling resistor (4), phase line (5), zero line (6) and residual current transformer (7) are all arranged in housing (1); One end of zero line (6) is electrically connected with the 3rd connection terminal (23); The other end of zero line (6) is electrically connected with the 4th connection terminal (24); One end of phase line current sampling resistor (4) is electrically connected with the first connection terminal (21); The other end of phase line current sampling resistor (4) is electrically connected with relay (3); One end of phase line (5) is electrically connected with the second connection terminal (22); The other end of phase line (5) is electrically connected with relay (3); Residual current transformer (7) is arranged at phase line (5) with zero line (6) mutually near place, and phase line (5) and zero line (6) are through residual current transformer (7); Circuit arrangement (8) is electrically connected respectively with relay (3), phase line current sampling resistor (4) and residual current transformer (7).
2. low-voltage network residual current monitoring system according to claim 1, is characterized in that: described communication channel (103) is RS485 bus.
3. low-voltage network residual current monitoring system according to claim 1, is characterized in that: described communication channel (103) is voltage Power Line Carrier Channel.
4. low-voltage network residual current monitoring system according to claim 1, is characterized in that: the circuit arrangement (8) of the described residual current measured electric energy meter (101) comprises voltage sample module (81), signal processing module (82), A/D modular converter (83), electric energy metering module (84), single chip processing module (85), relay control module (86), communication module (87), LCD display module (88), key-press module (89) and power module (80);
Voltage sample module (81), signal processing module (82), A/D modular converter (83), electric energy metering module (84), single chip processing module (85), relay control module (86), communication module (87) and power module (80) are arranged in housing (1);
Voltage sample module (81) is provided with signal output part; Signal processing module (82) is provided with voltage sampling signal input end, phase line current sampled signal input end, residual current signal input part and signal output part; A/D modular converter (83) is provided with signal input part, the first signal output part and secondary signal output terminal; Electric energy metering module (84) is provided with signal input part and signal output part; Single chip processing module (85) is provided with sampled signal input end, power consumption signal input end, relay control signal output terminal, communication ends, display output terminal and push button signalling input end; Relay control module (86) is provided with signal input part and control signal output terminal; Communication module (87) is provided with internal communication ends and correspondence with foreign country end; LCD display module (88) is provided with signal input part; Key-press module (89) is provided with signal output part;
The voltage sampling signal input end of signal processing module (82), phase line current sampled signal input end and residual current signal input part are respectively with signal output part, the phase line current sampling resistor (4) of voltage sample module (81) with residual current transformer (7) is corresponding is electrically connected; The signal input part of A/D modular converter (83) is electrically connected with the signal output part of signal processing module (82); The signal input part of electric energy metering module (84) is electrically connected with the first signal output part signal of A/D modular converter (83); The sampled signal input end of single chip processing module (85) is electrically connected with the secondary signal output end signal of A/D modular converter (83); The power consumption signal input end of single chip processing module (85) is electrically connected with electric energy metering module (84) signal output part signal; The signal input part of relay control module (86) is electrically connected with the relay control signal output end signal of single chip processing module (85); The control signal output terminal of relay control module (86) is electrically connected with the control end of relay (3); The internal communication ends of communication module (87) is electrically connected with the communication ends two-way signaling of single chip processing module (85); The correspondence with foreign country end of communication module (87) is electrically connected with described communication channel (103) signal; The signal input part of LCD display module (88) is electrically connected with the display output end signal of single chip processing module (85); The signal output part of key-press module (89) is electrically connected with the push button signalling input end signal of single chip processing module (85); Power module (80) provides working power.
CN201520181326.9U 2015-03-27 2015-03-27 A kind of low-voltage network residual current monitoring system Active CN204536414U (en)

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CN201520468644.3U CN204832327U (en) 2015-03-27 2015-03-27 Lower low voltage network residual current monitoring system of cost
CN201520181326.9U CN204536414U (en) 2015-03-27 2015-03-27 A kind of low-voltage network residual current monitoring system

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016070676A1 (en) * 2014-11-05 2016-05-12 江苏省电力公司常州供电公司 Smart electric meter capable of measuring residual current

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016070676A1 (en) * 2014-11-05 2016-05-12 江苏省电力公司常州供电公司 Smart electric meter capable of measuring residual current

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