Passive high voltage cable intermediate joint temperature measuring equipment
Technical field
The present invention relates to cable monitoring technical fields, are passive high voltage cable intermediate joint temperature measuring equipments specifically.
Background technique
High-tension cable is the conductor for being used for transmission and distributing electric energy in electric system, is different from overhead transmission line, and cable is general
It is embedded in underwater, underground or is laid in tunnel, pipeline, in channel.As the expansion of city size, high-tension cable obtain extensively
General application.On the other hand, the increase of cable dosage, the sustainable growth of power load, once breaking down, harm is serious.And
Cable intermediate joint existed by insulating material properties, manufacture craft and contact resistance, cold and hot contraction and sealed heat-dissipating etc. because
The influence of element, is particularly susceptible and breaks down.End failure is multiple failure and cable tunnel fire in cable tunnel
Arch-criminal.Fire was once made because cable tunnel inner cable head explodes by many enterprises, caused heavy loss.
These failures will undergo a progressive process by quantitative change to qualitative change, therefore, to cable intermediate joint
The variation of temperature for a long time, continuously monitor, so that it may understand and grasp its operation conditions.The prevention that past China takes
Property measure be periodical power failure carry out DC break down voltage and shake survey insulation, this can only have the case where obvious shortcoming to be reacted insulation,
It not can effectively prevent and reduce paroxysmal cable fault.And in actual motion before cable head fail, often generate heat,
Accelerate insulation ag(e)ing, eventually causes puncture short " blowing out ".Its skin temperature can be more high than under normal circumstances during this period.
It was found that the temperature of some joint location is excessively high or excessive with environment temperature difference or variation is too fast, just illustrate the exhausted of the position
Edge is weaker, or there are contact resistances to cause fever phenomenon.It continues to run and may result in serious failure generation,
System should issue alarm signal in time at this time, so that operator on duty is handled rapidly, avoid accident.
For the temperature monitoring of cable, the current country is mainly the following means:
1) temperature collecting cells such as thermocouple, thermal resistance are arranged in high-voltage cable insulating surface of outer sheath, measures partial points
Temperature, this method installation is simple, at low cost, can only generally survey hull-skin temperature, and larger by such environmental effects.
2) temperature sensing is carried out to temperature measuring point using infrared thermal imager, this method can only obtain the surface temperature of temperature measuring point
Degree, needs staff's handheld device to remove field monitoring, cannot accomplish that real-time online obtains temperature information.
3) distributed optical fiber temperature measurement is most common cable temperature monitoring means, this method by by fibre optic installations in
Cable surface, using based on by verifying Raman time domain reflection technology and OTDR optical time domain reflection technology, using reflected light with
The relationship of temperature monitors the temperature along optical fiber by measuring the size of reflected light.
Traditional thermocouple, resistance and temperature acquisition unit are covered in the insulating outer protective cover surface of high-tension cable, acquisition
Only skin temperature, with actual core temperature there are the biggish temperature difference, and it is influenced by environmental temperature, for connector etc.
The temperature of easy heat generating spot captures accuracy and substantially reduces, and reference significance is little, and the thermometric mode is chiefly used in switch cabinet of converting station
End, it is convenient to provide the place of power supply to data sink, it can not be arranged extensively in any temperature measuring point of long cable.
Using infrared thermal imager thermometric, needs staff to hold thermal imaging system to scene, institute is captured by thermal imaging system
Need temperature.And cable is generally layed in cable trench or buried soil and underwater.Do not have staff in most cases
The condition of handheld device scene thermometric.And thermal infrared imager capture be also cable insulation epidermis temperature.Between core
Possibly even reach tens of degree temperature difference.
Distributed optical fiber temperature measurement is also that temperature collecting cell is covered in cable insulation epidermis, is had with above-mentioned technology same
Limitation.The means focus on the temperature anomaly situation for monitoring whole cable run, the advantage with global analysis.But it is right
But there is limitation in the monitoring of part easily heating position.
Above-mentioned traditional thermometry is all unable to satisfy " emphasis monitors actual temperature at high-voltage cable middle joint core "
This actual demand.
Summary of the invention
The purpose of the present invention is to provide passive high voltage cable intermediate joint temperature measuring equipments, accurate to obtain among high-tension cable
Actual temperature at connector core is powered the space limitation for breaking temperature measuring point arrangement by CT power supply.
The present invention is achieved through the following technical solutions: passive high voltage cable intermediate joint temperature measuring equipment, including is mounted on electricity
In cable core connector engaging portion and middle part open up cyclic annular slot position connecting tube, are mounted on slot position and tightly docile is adopted in connecting tube temperature
Collection unit collects temperature Centralized processing unit and setting that multiple temperature collecting cells acquire data by RF radio-frequency module
The CT ring powered by Current Mutual Inductance to temperature collecting cell, temperature Centralized processing unit on high-tension cable;The temperature is adopted
Collect the sensor for the passive and wireless that unit is annular.
It, will be in high-tension cable when carrying out power network monitoring using passive high voltage cable intermediate joint temperature measuring equipment of the present invention
Between connector with setting temperature Centralized processing unit connecting tube connection, by CT ring by electric current incude be powered, multiple temperature
The temperature data of the high-voltage cable joint respectively acquired is sent at temperature Centralized by acquisition unit by RF radio-frequency communication
Unit is managed, while data exchange is carried out by temperature Centralized processing unit and backstage main station system.
Further, in order to preferably realize the present invention, the connecting tube both ends are the copper docked with cable core connector
Pipe fitting or aluminium tube joint, in slot position filled with wrap temperature collecting cell outer layer and flushed with cable core insulating layer half
Conductor adhesive tape layer.
Further, in order to preferably realize the present invention, the temperature Centralized processing unit includes connecting with RF radio-frequency module
The CPU that connects, the remote communication module and difference that temperature Centralized processing unit data are transmitted to backstage main station system are connect with CPU
Serial communication interface, the GPRS communication interface being connect with remote communication module.
In the present invention, temperature collecting cell constantly acquires temperature at corresponding high-voltage cable middle joint by the frequency acquisition of setting
Degree, and it is sent to temperature Centralized processing unit, the temperature of multiple temperature collecting cell acquisitions is summarized by temperature Centralized processing unit
Data.The temperature Centralized processing unit passes through remote communication module and its serial communication interface, the GPRS communication interface of connection
It is communicated with power supply system backstage main station system.User terminal can access power supply system network, directly to electric in compass of competency
Cable temperature is effectively supervised, and can also inquire temperature information by modes such as short messages.
Further, in order to preferably realize the present invention, the CT ring includes the current transformer for being coated at cable, and
It is sequentially connected in series the protection circuit in current transformer output end, rectification circuit, BUCK switch buck circuit, power supply output control electricity
Road, while power supply output control circuit also enables control circuit with switching power source chip and is connected;The BUCK switch buck circuit
Including switching power source chip U1 and the Voltage Feedback being connected between the anode and ground that switching power source chip U1 is inputted sampling electricity
Hinder R6, R7.
Further, in order to preferably realize the present invention, the protection circuit includes bidirectional triode thyristor Q1, bidirectional triode thyristor
Q2, resistance R1, resistance R2, resistance R3, zener diode D1, zener diode D2;The resistance R1, zener diode D1, with
Zener diode D1 oppositely arranged zener diode D2, resistance R2 is sequentially connected in series the first series circuit, bidirectional triode thyristor
The Q1 and resistance R3 that bidirectional triode thyristor Q1 control electrode is arranged in forms the second series circuit, the first series circuit, the second series electrical
Circuit is connected in parallel between its output terminal of current transformer AC1, output terminal AC2 simultaneously where road, silicon-controlled Q2;It is described controllable
The pole T2 of silicon Q2 is connected between bidirectional triode thyristor Q1, resistance R3, and the control electrode of bidirectional triode thyristor Q1 is connected to two pole of pressure stabilizing
Between pipe D2 and resistance R2.
Further, in order to preferably realize the present invention, the rectification circuit includes rectifier bridge VD1 and is connected in parallel on respectively whole
Flow diode D3, the super capacitor C1, super capacitor C2, capacitor C3 between its terminal 2 of bridge VD1 and terminal 4;The super capacitor
C1, super capacitor C2 are for bearing filtering and energy storage.
Further, in order to preferably realize the present invention, the BUCK switch buck circuit further include sustained diode 4,
Play the energy storage inductor L1 of energy storage, play filter capacitor C4, C5, C6, C7 of energy storage and filter action;The switching power source chip
1 foot of U1 connects input power anode, and 3 feet of switching power source chip U1 connect the ground of input power, switching power source chip U1 output end 2
Foot connects the cathode of sustained diode 4 and one end of energy storage inductor L1, the plus earth of sustained diode 4, energy storage inductor L1
The other end be connected with the anode of filter capacitor C4, C5, C6, C7, switching power source chip U1 control 5 foot control level of foot by switching
Power supply chip enables control circuit and generates;Voltage Feedback sample resistance R6, R7 series connection be followed by out-put supply anode and cathode it
Between, the connecting pin of Voltage Feedback sample resistance R6, R7 are connected with 4 foot of feedback voltage input pin of switching power source chip U1.
Sustained diode 4 plays afterflow when Switching Power Supply is exported and turned off in the BUCK switch buck circuit;Energy storage
Inductance L1 plays energy storage;Filter capacitor C4, C5, C6, C7 play energy storage and filter action;Voltage Feedback sample resistance R6, R7 will
Output voltage sampling access switching power source chip U1, enables switching power source chip U1 accurately to adjust voltage, adjusts Voltage Feedback and take
The ratio of sample resistance R6, R7 can realize output voltage adjustment function.
Further, in order to preferably realize the present invention, it includes comparator that the switching power source chip, which enables control circuit,
A1, voltage reference chip TL431, zener diode D5, triode Q3, triode Q4 and resistance R31, R32, R33, R34,
R35, zener diode D5, triode Q3 form pressure stabilizing output unit;The connecting pin of described Voltage Feedback sample resistance R6, R7 connect
Enter 3 foot of positive input terminal of comparator A1, the negative input end 2 of 2 foot of the output pin access comparator A1 of voltage reference chip TL431
1 foot of output pin of foot, comparator A1 is connect by resistance R35 with the base stage of triode Q4, and 8 foot of power input of comparator A1 connects
The emitter-base bandgap grading of triode Q3,4 foot of ground input terminal of comparator A1 connect the ground of switching power source chip U1 input, the output end of comparator A1
1 foot is pulled upward to the emitter-base bandgap grading of triode Q3 by resistance R34;The one end the resistance R31 and switching power source chip U1 Input voltage terminal
And triode Q3 collector is connected, the other end of resistance R31 is connected with the cathode of the base stage of triode Q3 and zener diode D5,
The anode of zener diode D5 connects power ground, and the emitter-base bandgap grading input voltage of triode Q3 is limited by D5 cathode voltage at zener diode
System, voltage stabilization is below setting voltage value;One end of the resistance R32 is connected with triode Q3 emitter-base bandgap grading, and the other end is compared with
2 foot of negative input end of device A1 and 1,2 feet of voltage reference chip TL431 are connected;The resistance R33 connection comparator A1's is just defeated
Enter 3 feet of end and 1 foot of output end;The resistance R35 is connected to the emitter-base bandgap grading of triode Q3 and the base stage of triode Q4, triode Q4's
Emitter-base bandgap grading connects power ground, and the control foot of the collector connection switch power supply chip U1 of triode Q4 simultaneously passes through resistance R36 and triode
The emitter-base bandgap grading of Q3 is connected.
The switching power source chip enables control circuit and realizes that the sluggish of input voltage is compared, and turns off and opens when brownout
Powered-down source chip U1.
Further, in order to preferably realize the present invention, the power supply output control circuit is mainly by comparator A2, three poles
Pipe Q5, field-effect tube Q6, LED light D7 and resistance R5, R19, R20, R21, R22 composition;The Voltage Feedback sample resistance R6,
The junction R7 is connect with 5 foot of positive input terminal of comparator A2,6 foot of negative input end and voltage reference chip TL431 of comparator A2
The reference voltage foot of generation is connected, and 7 foot of output end of comparator A2 is connected to out-put supply anode, resistance R19 by resistance R20
Both ends be connected on 7 foot of 5 foot of positive input terminal and output end of comparator A2, resistance R21 connection comparator A2 output end 7
The collector of the base stage of foot and triode Q5, triode Q5 emitter grounding, triode Q5 is connected with the grid of field-effect tube Q6, electricity
One end of resistance R5 is connect with the collector of triode Q5 and the source electrode of the other end of resistance R5 and field-effect tube Q6 are connected, field-effect
The drain electrode of pipe Q6 connects the final output of power supply;The resistance R22 connects with LED light D7 is followed by drain electrode and the ground of scene effect pipe Q6
Between.
The power supply output control circuit realizes that the sluggish of output voltage is compared, and when voltage is lower than setting value, passes through field
The output of effect pipe power cutoff, and can indicate whether power supply has output by LED light D7.
Compared with prior art, the present invention have the following advantages that and the utility model has the advantages that
(1) present invention accurately obtains high-voltage cable middle joint by installation temperature collecting cell connecting tube in setting slot position
Core temperature, rather than the temperature of surface coat;
(2) present invention setting CT ring, do not need battery power supply, only by electric current induction mode obtain temperature collecting cell,
The power supply that temperature Centralized processing unit needs;
(3) present invention designs the power supply on the spot for realizing temperature Centralized processing unit by unique CT power supply, breaks thermometric
The space limitation of point arrangement;
(4) present invention realizes the remote data communication with backstage main station system by remote communication module, and realization remotely exists
Line monitors the operating parameter of cable, provides the necessary technical means for supervision power grid.
Detailed description of the invention
Fig. 1 is passive high voltage cable intermediate joint temperature measuring equipment use state diagram;
Fig. 2 is the structural schematic diagram of connecting tube;
Fig. 3 is the schematic diagram for protecting circuit;
Fig. 4 is the schematic diagram of rectification circuit;
Fig. 5 is the schematic diagram of BUCK switch buck circuit;
Fig. 6 is the schematic diagram that switching power source chip enables control circuit;
Fig. 7 is the schematic diagram of power supply output control circuit;
Fig. 8 is the internal circuit schematic diagram of CT ring;
Wherein: 001- connecting tube;002- temperature collecting cell;003- temperature Centralized processing unit;004-CT ring.
Specific embodiment
The present invention is described in further detail below with reference to embodiment, embodiments of the present invention are not limited thereto.
Embodiment 1:
Passive high voltage cable intermediate joint temperature measuring equipment as shown in Figure 1 and Figure 2, including is mounted on the combination of cable core connector
In portion and middle part open up cyclic annular slot position connecting tube 001, are mounted on slot position and tightly docile is in 001 temperature collecting cell of connecting tube
002, temperature Centralized processing unit 003, the Yi Jishe that multiple temperature collecting cells 002 acquire data are collected by RF radio-frequency module
Set the CT ring 004 powered by current transformer to temperature Centralized processing unit 003 on high-tension cable;The temperature acquisition list
Member 002 is the sensor of the passive and wireless of annular.
Cable intermediate connector nearby can not almost provide 220V alternating current, in order to ensure temperature information can be sent in time
Daemon software platform, this programme use CT ring 004 and take and can and power for temperature Centralized processing unit 003.It can reduce into this way
This, simply solves the problems, such as data remote transmission.
As shown in Figure 1, it is temperature that the present invention, which obtains the energy on high-voltage cable using electric current principle of induction by CT ring 004,
Centralized processing unit 003 is spent to power.Multiple temperature collecting cells 002 are transmitted data summarization is single to temperature Centralized processing by RF
Member 003, and realized by temperature Centralized processing unit 003 by remote communication module and led to the teledata of backstage main station system
News realize the operating parameter of remote on-line monitoring cable.Backstage main station system can integrate the letter of multiple temperature Centralized collectors
Breath.
As shown in Fig. 2, the present invention installs 002 connecting tube 001 of annular temperature collecting cell by slot position, cable core is realized
The accurate measurement of temperature.001 both ends of connecting tube are the copper pipe joint or aluminium tube joint docked with cable core connector, slot position
In filled with wrapping in 002 outer layer of temperature collecting cell and the semi-conductor adhesive belt that is flushed with cable core insulating layer.
When installation, both ends cable core end is inserted into respectively in its copper pipe joint of cable intermediate joint or aluminium tube joint, is led to
Cross after hydraulic tongs compress, temperature collecting cell 002 is tightly attached to cable intermediate joint slot position, wind semi-conductor adhesive band to ensure and
Cable insulation flushes.After end installs prefabricated cold shrink sleeve, in order to ensure wireless signal energy when winding shields copper mesh
The gap of 2-3 5mm wide should be reserved across shielding copper mesh.Reserving gaps are for field distribution etc. without influence.
In addition, 001 middle part of crimping connecting tube should be avoided when hydraulic tongs crimp cable intermediate joint, avoid to temperature
The pressure of acquisition unit 002 is destroyed.
It is difficult that the present invention is obtained for temperature measuring point actual temperature, has carried out design again to the transition joint of high-tension cable,
As connecting tube 001 in the present invention.001 integrated design of entire connecting tube, reserved 002 slot position of temperature collecting cell in centre, temperature
Degree acquisition unit 002 is fitted into the practical heating temperature that can directly acquire core.The connecting tube 001 be copper pipe or aluminum pipe,
Cable core accesses copper pipe or aluminum pipe, and is fixed using hydraulic tongs.The access of connecting tube 001 in the present invention, will not be to height
The electric field of equipment is pressed to generate distortion.The semi-conductor adhesive band copper pipe that is intertwined and connected is allowed to concordant with cable insulation, reuses shrinkage set
Pipe post-processing does not increase any accessory, has technique aesthetic feeling.
Embodiment 2:
The present embodiment advanced optimizes on that basi of the above embodiments, further, the temperature Centralized processing unit
003 include the CPU being connect with RF radio-frequency module, connect with CPU 003 data of temperature Centralized processing unit are transmitted to backstage main website
The remote communication module of system and the serial communication interface being connect respectively with remote communication module, GPRS communication interface.
There are serial communication interface or GPRS communication interface inside the temperature Centralized processing unit 003, multiple twin can be passed through
Line or mobile phone signal are sent to backstage main station system, carry out Correlative data analysis and accident early warning service.
The temperature Centralized processing unit 003 passes through the temperature information that 2.4G frequency collection temperature collecting cell 002 transmits.
Meanwhile the temperature Centralized processing unit 003 receives message search request by serial communication interface or GPRS communication interface,
After receiving short message enquiry, query information is actively replied.User can actively obtain 002 phase of temperature collecting cell by the function
Close acquisition situation.RS232/RS485 interface is arranged in the temperature Centralized processing unit 003.The temperature Centralized processing unit 003
Alarm temperature I value, II value can be set by 485 interface of MODBUS or short message;When measuring temperature and reaching alarming value, temperature
Degree centralized processing unit will be indicated by LED light and send short message progress alarm prompt by built-in GPRS module.
When carrying out information transmission using SMS, backstage main station system data acquisition and analysis.It is super that temperature occurs
Temperature over-range alarm message is sent from the equipment person liable of trend default in limited time.
Short message content includes: the information such as location of the machine to be installed, current temperature, 002 operating voltage of wireless temperature acquisition unit.
Transmission frequency can be set.Such as: sending set of frequency is every 5 minutes primary, if user is afraid of that harassing and wrecking can actively reply stopping
Order, system then stop sending short message alarm.
When being carried out data transmission using GPRS, by GPRS by the relevant information synchronous driving of acquisition to backstage system of main website
System.The case where being installed according to backstage (electric power Intranet or internet net), user can remotely access backstage main station system phase
Close data.
The present invention all uses wireless communication mode.It is adopted between temperature collecting cell 002 and temperature Centralized processing unit 003
With Zigbee mechanics of communication, frequency 2.4GHz.The technology has a low-power consumption, low complex degree, and network capacity is big, can the spies such as ad hoc network
Point.Using the data-transmission mode can convenient, flexible arrangement temperature measuring point, when signal strength is inadequate, pass through increase repeater realize
The force transfer of signal.When temperature measurement terminal is increased with reducing, dynamic reorganization is may be implemented in temp measuring system.Different from computer network
User obtains node information by IP address, and centered on the operation of entire temp measuring system is transmitted by data, each node can pass through
The acquisition of the signal relay realization most concerned temperature information data of user.Temperature Centralized processing unit collects temperature collecting cell
002 all temperature informations.Serial communication and GPRS communication are provided, by temperature data be transmitted to monitoring backstage for
Analysis.When temperature over-range occurs, data concentrator is sent to responsible person concerned by built-in GPRS module, by warning information.
High-voltage cable middle joint is along cable distribution, and much tens kilometers of the length of a cable, along the line without special electricity
Source is the power supply of temperature Centralized processing unit.Thus traditional wireless temperature measurement mode is unable to satisfy system flexible arrangement, adapts to scene
The demand of situation.For the difficult problem of temperature Centralized processing unit power supply, the present invention devises a CT power supply, in primary side electricity
When stream reaches 17A, temperature Centralized processing unit steady operation can be driven.Solving taking for temperature Centralized processing unit can ask
Topic, then whole system build just become it is flexible with it is abundant.We can arrange our temp measuring system in any place, gram
Take spatially bring limitation.
Embodiment 3:
The present embodiment advanced optimizes on that basi of the above embodiments, as shown in figure 8, the CT ring 004 includes housing
In the current transformer of cable, and it is sequentially connected in series current transformer, protection circuit, rectified current in current transformer output end
Road, BUCK switch buck circuit, power supply output control circuit, while power supply output control circuit is also enabled with switching power source chip
Control circuit is electrically connected.
The protection circuit is CT output overvoltage protection circuit, limits power input voltage in OK range, avoids inputting
Overtension leads to late-class circuit component wear.
After CT output terminals A C1, AC2 voltage difference is greater than 39V, voltage will be gradually increasing on resistance R2, reach triode Q1's
Triode Q1 is connected after opening thresholding.After triode Q1 conducting, current flowing resistance R3, as the raising of CT output voltage, resistance R3
Upper voltage is greater than triode Q2 cut-in voltage, triode Q2 conducting, and CT output is short-circuited, and high voltage is not transferred to rear class electricity
Road.
As shown in figure 3, the protection circuit includes bidirectional triode thyristor Q1, bidirectional triode thyristor Q2, resistance R1, resistance R2, electricity
Hinder R3, zener diode D1, zener diode D2;It is the resistance R1, zener diode D1, oppositely arranged with zener diode D1
Zener diode D2, resistance R2 be sequentially connected in series the first series circuit, bidirectional triode thyristor Q1 and be arranged in bidirectional triode thyristor
The resistance R3 of Q1 control electrode forms the second series circuit, and circuit where the first series circuit, the second series circuit, silicon-controlled Q2 is same
When be connected in parallel between its output terminal of current transformer AC1, output terminal AC2;The pole T2 of the silicon-controlled Q2 is connected to two-way
Between silicon-controlled Q1, resistance R3, and the control electrode of bidirectional triode thyristor Q1 is connected between zener diode D2 and resistance R2.
Exchange is converted to direct current by the rectification circuit.Super capacitor C1, super capacitor C2 are that capacitance is biggish super
Capacitor plays filtering and energy storage.
As shown in figure 4, the rectification circuit includes rectifier bridge VD1 and is connected in parallel on its terminal 2 of rectifier bridge VD1 and terminal respectively
Diode D3, super capacitor C1, super capacitor C2, capacitor C3 between 4;The super capacitor C1, super capacitor C2 are for bearing
Load filtering and energy storage.
As shown in figure 5, the BUCK switch buck circuit further includes sustained diode 4, the energy storage inductor for playing energy storage
L1, filter capacitor C4, C5, C6, the C7 for playing energy storage and filter action;1 foot of the switching power source chip U1 is connecing input power just
Pole, 3 feet of switching power source chip U1 connect the ground of input power, and 2 foot of switching power source chip U1 output end connects sustained diode 4
Cathode and energy storage inductor L1 one end, the plus earth of sustained diode 4, the other end and filter capacitor of energy storage inductor L1
The anode of C4, C5, C6, C7 are connected, and switching power source chip U1 control 5 foot control level of foot is made to can control electricity by switching power source chip
Road generates;Voltage Feedback sample resistance R6, R7 series connection are followed by between out-put supply anode and cathode, Voltage Feedback sample resistance
The connecting pin of R6, R7 are connected with 4 foot of feedback voltage input pin of switching power source chip U1.
The DC voltage that rectification circuit exports is down to the lower electricity of electrical equipment needs by the BUCK switch buck circuit
Pressure.This circuit can adjust output voltage by adjusting Voltage Feedback sample resistance R6, R7.
Sustained diode 4 plays afterflow when Switching Power Supply is exported and turned off;Energy storage inductor L1 plays energy storage;Filtering
Capacitor C4, C5, C6, C7 play energy storage and filter action;Output voltage is sampled access switch by Voltage Feedback sample resistance R6, R7
Power supply chip U1, enables switching power source chip U1 accurately to adjust voltage, and the ratio of adjusting Voltage Feedback sampling R6, R7 can be realized defeated
Voltage adjusts function out.
The switching power source chip enables control circuit, and effect is the reliably disconnecting circuit when input voltage is too low, and
Allow circuit can be with intermittent work when input power is smaller to take up load completely.It may be led without the mistake low-voltage of control
It causes late-class circuit or electricity consumption element manipulation in critical state, causes wrong and unexpected.
As shown in fig. 6, the switching power source chip enable control circuit include comparator A1, voltage reference chip TL431,
Zener diode D5, triode Q3, triode Q4 and resistance R31, R32, R33, R34, R35, zener diode D5, triode
Q3 forms pressure stabilizing output unit;The positive input terminal 3 of the connecting pin access comparator A1 of described Voltage Feedback sample resistance R6, R7
Foot, 2 foot of negative input end of 2 foot of the output pin access comparator A1 of voltage reference chip TL431,1 foot of output pin of comparator A1
It is connect by resistance R35 with the base stage of triode Q4,8 foot of power input of comparator A1 connects the emitter-base bandgap grading of triode Q3, comparator
4 foot of ground input terminal of A1 connects the ground of switching power source chip U1 input, and 1 foot of output end of comparator A1 is pulled upward to by resistance R34
The emitter-base bandgap grading of triode Q3;The one end the resistance R31 is connected with switching power source chip U1 Input voltage terminal and triode Q3 collector,
The other end of resistance R31 is connected with the cathode of the base stage of triode Q3 and zener diode D5, and the anode of zener diode D5 connects
The emitter-base bandgap grading input voltage of power ground, triode Q3 is limited by D5 cathode voltage at zener diode, and voltage stabilization is in setting voltage
Value is following;One end of the resistance R32 is connected with triode Q3 emitter-base bandgap grading, 2 foot of negative input end and electricity of the other end and comparator A1
1,2 feet of fiducial chip TL431 are pressed to be connected;1 foot of 3 foot of positive input terminal and output end of the resistance R33 connection comparator A1;Institute
It states resistance R35 and is connected to the emitter-base bandgap grading of triode Q3 and the base stage of triode Q4, the emitter-base bandgap grading of triode Q4 meets power ground, triode Q4
Collector connection switch power supply chip U1 control foot and be connected with the emitter-base bandgap grading of triode Q3 by resistance R36.
The switching power source chip enables control circuit and realizes that the sluggish of input voltage is compared, and turns off and opens when brownout
Powered-down source chip.
The power supply output control circuit working principle is identical as the enabled control circuit working principle of switching power source chip.?
It is disconnected when output voltage is too low, when preventing brownout, user equipment operation irregularity.The design of CT power supply ensure that temperature Centralized
The normal work power supply of processing unit.Temperature Centralized processing unit normal work can be driven when primary side current reaches 17A.
As shown in fig. 7, the power supply output control circuit is mainly by comparator A2, triode Q5, field-effect tube Q6, LED
Lamp D7 and resistance R5, R19, R20, R21, R22 composition;The junction Voltage Feedback sample resistance R6, R7 is with comparator A2's
The connection of 5 foot of positive input terminal, 6 foot of negative input end of comparator A2 are connected with the reference voltage foot that voltage reference chip TL431 is generated,
7 foot of output end of comparator A2 is connected to out-put supply anode by resistance R20, and the both ends of resistance R19, which are connected to, compares
On 7 foot of 5 foot of positive input terminal and output end of device A2, the base stage of resistance R21 connection comparator A2 output end 7 foot and triode Q5,
The collector of triode Q5 emitter grounding, triode Q5 is connected with the grid of field-effect tube Q6, one end of resistance R5 and triode
The collector of Q5 connects and the other end of resistance R5 is connected with the source electrode of field-effect tube Q6, and the drain electrode of field-effect tube Q6 connects power supply
Final output;The resistance R22 connects with LED light D7 to be followed by between the drain electrode and ground of scene effect pipe Q6.Our department's parallel circuit is real
The sluggish of existing output voltage is compared, and when voltage is lower than setting value, is exported by field-effect tube power cutoff, and can pass through LED
Whether lamp D7 instruction power supply has output.
Embodiment 4:
The present embodiment advanced optimizes on that basi of the above embodiments, passive high voltage cable intermediate joint temperature measuring equipment,
Including connecting tube 001, positioned at the temperature collecting cell 002 of high-tension cable core junction and multiple 002 nothings of temperature collecting cell
The temperature Centralized processing unit 003 of line communication.The temperature collecting cell 002, temperature Centralized processing unit 003 are by being set in
CT ring 004 on high-voltage cable passes through electric current inductive power supply.
It is mounted on cable core connector engaging portion and middle part opens up cyclic annular slot position connecting tube 001, is mounted in slot position and tight
It is close to clothes and collects the multiple acquisition of temperature collecting cells 002 numbers in 001 temperature collecting cell 002 of connecting tube, by RF radio-frequency module
According to temperature Centralized processing unit 003 and be arranged on high-tension cable by Current Mutual Inductance to temperature collecting cell 002, temperature
Spend the CT ring 004 that centralized processing unit 003 is powered;The temperature collecting cell 002 is the sensor of the passive and wireless of annular.
The wireless communication distance at least 10m of the temperature collecting cell 002.Wireless communication distance is too short, a temperature collection
The covered high-tension cable core connector negligible amounts of middle 003 acquisition range of processing unit institute, device layout are limited.
The temperature acquisition range of the temperature collecting cell 002 is -20 DEG C to 150 DEG C.This temperature range meets high-voltage electricity
Temperature requirement when cable practical normal work.
The temperature acquisition period of the temperature collecting cell 002 is not more than 2min.Excessive cycle is unfavorable for temperature data
Real-time Feedback, the period, too short acquisition data were more, and data processing amount is big, be easy to cause system redundancy.
The weight of the temperature collecting cell 002 is 20g.The angle born a heavy burden from cable, temperature collecting cell 002
Weight is the smaller the better, but pursues the light-weight of temperature collecting cell 002 simply, excessively high to technical requirements, also will increase cost branch
Out, deficiency in economic performance.
003 radio frequency standard of temperature Centralized processing unit is IEEE802.15.4.Each temperature Centralized processing unit
003 can manage 002 quantity of temperature collecting cell at 10000 or more.
The above is only presently preferred embodiments of the present invention, not does limitation in any form to the present invention, it is all according to
According to technical spirit any simple modification to the above embodiments of the invention, equivalent variations, protection of the invention is each fallen within
Within the scope of.