CN209056980U - A kind of three-phase voltage remotely monitors and protection circuit - Google Patents
A kind of three-phase voltage remotely monitors and protection circuit Download PDFInfo
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- CN209056980U CN209056980U CN201822006699.9U CN201822006699U CN209056980U CN 209056980 U CN209056980 U CN 209056980U CN 201822006699 U CN201822006699 U CN 201822006699U CN 209056980 U CN209056980 U CN 209056980U
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Abstract
The utility model discloses a kind of three-phase voltages remotely to monitor and protection circuit; including signal conditioning module, main control chip, serial port module and the end PC; the output end of the signal conditioning module and the input terminal of main control chip connect; the main control chip is bi-directionally connected with serial port module, and the serial port module is bi-directionally connected with the end PC；The signal conditioning module includes signal reduction voltage circuit, signal transformation circuit and AD protection circuit; the output end of the signal reduction voltage circuit and the input terminal of signal transformation circuit connect; the output end of the signal transformation circuit is connect with the input terminal of AD protection circuit, and the output end of the AD protection circuit and the input terminal of main control chip connect.The utility model has the advantages that cheap, low-loss, computing capability are strong, data processing is fast, precision is high, remote controlled.
Description
Technical field
The utility model relates to safety technique for using electricity fields, remotely monitor more particularly, to a kind of three-phase voltage and protection electricity
Road.
Background technique
With flourishing for economic construction of China, demand of the society to electric power resource is growing, and user is to power train
The requirement of system is also higher and higher, and the reliability and stability of power supply have become the weight for ensureing economic growth and meeting user demand
Want problem.In modern industry electricity consumption, any electrical equipment failure will lead to assembly line, even entire factory makees
The interruption of industry causes unthinkable loss.Meanwhile for ordinary user, household electrical appliance are for a long time in non-voltage rating or frequency
It works under rate, the service life of electrical equipment can be seriously affected.We are also in the epoch of one " movement ", mobile office, shifting
Dynamic communication, mobile leisure and amusement, in mobile state, people not only need the low-voltage direct supplied by battery or storage battery
Electricity, while with greater need for our indispensable 220 volts of alternating currents in surroundings, therefore it is same in inverter to meet our demands
When, higher technical requirements are proposed to the stability of the three-phase voltage of inverter output.Three-phase voltage protection used at present
Device is mostly to use transformer and bridge circuit to carry out signal condition, and control core is the circuit structure of single-chip microcontroller, this circuit
It is expensive, have ferromagnetic loss although being simply easily achieved, and that there are computing capabilitys is poor, data processing speed is slow, essence
Spend low problem.
Utility model content
The purpose of the utility model is to overcome above-mentioned deficiencies in the prior art, provide a kind of three-phase voltage monitoring electricity
Road, the circuit device have that cheap, low-loss, computing capability is strong, data processing is fast, precision is high, remote controlled excellent
Point.
In order to achieve the above purposes, the technical solution adopted by the utility model is:, and a kind of three-phase voltage remotely monitors and protection
Circuit, it is characterised in that: including signal conditioning module, main control chip, serial port module and the end PC, the signal conditioning module it is defeated
The connection of the input terminal of outlet and main control chip, the main control chip are bi-directionally connected with serial port module, the serial port module and the end PC
It is bi-directionally connected；The signal conditioning module includes signal reduction voltage circuit, signal transformation circuit and AD protection circuit, the signal drop
The output end of volt circuit and the input terminal of signal transformation circuit connect, and the output end and AD of the signal transformation circuit protect circuit
Input terminal connection, the output end of AD protection circuit and the input terminal of main control chip connect.
A kind of above-mentioned three-phase voltage remotely monitors and protection circuit, it is characterised in that: the end PC is to be equipped with RS232
Interface and the personal computer that three-phase voltage data monitoring and obstruction warning status inquiry can be carried out.
A kind of above-mentioned three-phase voltage remotely monitors and protection circuit, it is characterised in that: the main control chip is for model
TMS320F28035 and dsp chip containing 16X12 AD conversion ends, No. 28 pins of the main control chip are data receiver
End, No. 24 pins of the main control chip are data sending terminal.
A kind of above-mentioned three-phase voltage remotely monitors and protection circuit, it is characterised in that: the signal reduction voltage circuit includes
Primary coil current-limiting resistance R1, the Hall voltage sensor for measuring resistance R2 and model LV25-P, primary coil current-limiting resistance
The resistance value of R1 is 12K Ω, and the resistance value of the measurement resistance R2 is 33 Ω, No. 1 pin of the Hall voltage sensor and former line
One end connection of current-limiting resistance R1 is enclosed, the other end of primary coil current-limiting resistance R1 is signal input part, the Hall voltage
No. 2 pins of sensor are grounded, and No. 3 pins of the Hall voltage sensor are connect with one end of measurement resistance R2, the survey
Measure the other end ground connection of resistance the R2 ,+12V power supply that No. 4 pins and external power source circuit of the Hall voltage sensor provide
Connection, No. 5 pins of the Hall voltage sensor are connect with -12V the power supply that external power source circuit provides, the Hall voltage
No. 3 pins of sensor are signal output end, the input terminal of No. 3 pins and signal transformation circuit of the Hall voltage sensor
Connection.
A kind of above-mentioned three-phase voltage remotely monitors and protection circuit, it is characterised in that: the signal transformation circuit includes
LM324 chip, a potentiometer W1 and four resistance values are resistance R1, resistance R2, resistance R3 and the resistance R4 of 1K, the current potential
No. 1 end of device W1 is connect with+3.3V the power supply that external power source circuit provides, No. 2 ends ground connection of the potentiometer W1, the current potential
No. 3 ends of device W1 are connect with one end of resistance R2, and the 3 of the other end of the resistance R2 and one end of resistance R1 and LM324 chip
Number pin is all connected with, and No. 1 pin and No. 2 pins of the LM324 chip are connect with resistance R4, and No. 2 of the LM324 chip
Pin is connect with one end of resistance R3, the other end ground connection of the resistance R3, No. 4 pins and external electrical of the LM324 chip
+ 15V power supply the connection that source circuit provides, the other end of the resistance R1 are signal input part, the other end of the resistance R1 with
No. 3 pins of Hall voltage sensor connect, and No. 1 pin of the LM324 chip is signal output end, the LM324 chip
The input terminal of No. 1 pin and AD protection circuit connect.
A kind of above-mentioned three-phase voltage remotely monitors and protection circuit, it is characterised in that: the AD protection circuit includes two
Pole pipe DQ1 and diode DQ2, the plus earth of the diode DQ1, the cathode of the diode DQ1 and the sun of diode DQ2
Pole connection, the cathode of the diode DQ2 are connect with+3.3V the power supply that external power source circuit provides, the yin of the diode DQ1
Pole and the anode junction of diode DQ2 connect with No. 1 pin of LM324 chip and the position the 16X12 AD conversion end of main control chip
It connects.
A kind of above-mentioned three-phase voltage remotely monitors and protection circuit, it is characterised in that: the serial port module includes
MAX232 chip and four 104 capacitors, four 104 capacitors are respectively capacitor C1, capacitor C2, capacitor C3 and capacitor C4, institute
No. 1 pin and No. 3 pins for stating MAX232 chip are connect with the both ends of capacitor C1 respectively, No. 4 pins of the MAX232 chip
Connect respectively with the both ends of capacitor C2 with No. 5 pins, No. 2 pins and No. 16 pins of the MAX232 chip respectively with capacitor C3
Both ends connection, No. 15 pins and No. 6 pins of the MAX232 chip connect with the both ends of capacitor C4 respectively, the MAX232
No. 16 pins of chip are connect with+3.3V the power supply that external power source circuit provides, No. 6 pins ground connection of the MAX232 chip,
No. 10 pins of the MAX232 chip are DSP data sending terminal, No. 10 pins of the MAX232 chip and main control chip
The connection of No. 28 pins, No. 9 pins of the MAX232 chip are DSP data receiver, No. 9 pins of the MAX232 chip with
No. 24 pins of main control chip connect and realization and main control chip two-way communication, No. 8 pins of the MAX232 chip are PC number
According to receiving end, No. 8 pins of the MAX232 chip are connect by Serial Port Line with No. 3 endpoints of the RS232 interface at the end PC, described
No. 7 pins of MAX232 chip are PC data sending terminal, and No. 7 pins of the MAX232 chip pass through Serial Port Line and the end PC
No. 7 endpoints of RS232 interface are connected and are realized and the two-way communication of the end PC.
Compared with the prior art, the utility model has the following advantages:
1, the utility model uses dsp chip as control core, with interface is convenient, stability is good, precision is high, can weigh
It answers, operational capability is strong, fireballing advantage.
2, the utility model carries out signal condition using Hall voltage sensor and Noninverting summing operation circuit, has precision
The fast advantage of height, good linearity, bandwidth, response.
3, the utility model uses power level conversion chip of the MAX232 chip as serial port module, has low in energy consumption
Advantage.
4, the utility model is furnished with the end PC, can remotely monitor instantaneous value, virtual value, frequency and the phase of three-phase voltage, when
Instantaneous value, phase shortage, misphase detection are broken down, and are exported fault message immediately, can be monitored in real time, and electric appliance loss, protection are reduced
Economic loss.
Below by drawings and examples, the utility model is further described in detail.
Detailed description of the invention
Fig. 1 is the schematic block circuit diagram of the utility model.
Fig. 2 is the circuit diagram of the utility model signal reduction voltage circuit.
Fig. 3 is the circuit diagram of the utility model signal transformation circuit.
Fig. 4 is the circuit diagram that the utility model AD protects circuit.
Fig. 5 is the circuit diagram of the utility model serial port module.
Description of symbols:
1-signal conditioning module；2-main control chips；3-serial port modules；
4-the ends PC；5-signal reduction voltage circuits；6-signal transformation circuits；
7-AD protect circuit.
Specific embodiment
As shown in Figure 1, the utility model includes signal conditioning module 1, main control chip 2, serial port module 3 and the end PC 4, it is described
The output end of signal conditioning module 1 is connect with the input terminal of main control chip 2, the main control chip 2 and the two-way company of serial port module 3
It connects, the end serial port module 3 and PC 4 is bi-directionally connected；The signal conditioning module 1 includes signal reduction voltage circuit 5, signal shaping electricity
Road 6 and AD protect circuit 7, and the output end of the signal reduction voltage circuit 5 is connect with the input terminal of signal transformation circuit 6, the letter
The output end of number shaping circuit 6 connect with the input terminal of AD protection circuit 7, the output end and master control core of the AD protection circuit 7
The input terminal of piece 2 connects.
In the present embodiment, the end PC 4 is to be equipped with RS232 interface and can carry out three-phase voltage data monitoring and obstacle report
The personal computer of alert status inquiry, the personal computer that the end PC 4 is sold by market.
In the present embodiment, the main control chip 2 is that model is TMS320F28035 and containing 16X12 AD conversion ends
Dsp chip, No. 28 pins of the main control chip 2 are data receiver, and No. 24 pins of the main control chip 2 are data transmission
End, the dsp chip that the TMS320F28035 chip is sold by market.
As shown in Fig. 2, the signal reduction voltage circuit 5 includes primary coil current-limiting resistance R1, measurement resistance R2 and model
The Hall voltage sensor of LV25-P, the resistance value of primary coil current-limiting resistance R1 are 12K Ω, the resistance value of the measurement resistance R2
No. 1 pin for 33 Ω, the Hall voltage sensor is connect with one end of primary coil current-limiting resistance R1, primary coil current limliting
The other end of resistance R1 is signal input part, and No. 2 pins of the Hall voltage sensor are grounded, the Hall voltage sensor
No. 3 pins with measurement resistance R2 one end connect, it is described measurement resistance R2 the other end be grounded, the Hall voltage sensor
No. 4 pins connect with+12V the power supply that external power source circuit provides, No. 5 pins and external electrical of the Hall voltage sensor
- 12V power supply the connection that source circuit provides, No. 3 pins of the Hall voltage sensor are signal output end, the Hall voltage
No. 3 pins of sensor are connect with the input terminal of signal transformation circuit 6.
As shown in figure 3, it is 1K that the signal transformation circuit 6, which includes LM324 chip, a potentiometer W1 and four resistance values,
Resistance R1, resistance R2, resistance R3 and resistance R4, the potentiometer W1 the+3.3V electricity that is provided with external power source circuit of No. 1 end
Source connection, No. 2 ends ground connection of the potentiometer W1, No. 3 ends of the potentiometer W1 are connect with one end of resistance R2, the resistance
The other end of R2 is all connected with one end of resistance R1 and No. 3 pins of LM324 chip, No. 1 pin of the LM324 chip and 2
Number pin is connect with resistance R4, and No. 2 pins of the LM324 chip are connect with one end of resistance R3, and the resistance R3's is another
One end ground connection, No. 4 pins of the LM324 chip are connect with+15V the power supply that external power source circuit provides, the resistance R1's
The other end is signal input part, and the other end of the resistance R1 and No. 3 pins of Hall voltage sensor connect, the LM324
No. 1 pin of chip is signal output end, and No. 1 pin of the LM324 chip is connect with the input terminal of AD protection circuit 7.
As shown in figure 4, the AD protection circuit 7 includes diode DQ1 and diode DQ2, the anode of the diode DQ1
Ground connection, the cathode of the diode DQ1 are connect with the anode of diode DQ2, cathode and the external power supply electricity of the diode DQ2
+ 3.3V power supply the connection that road provides, the cathode of the diode DQ1 and the anode junction of diode DQ2 and LM324 chip
The position the 16X12 AD conversion end of No. 1 pin and main control chip 2 is all connected with.
As shown in figure 5, the serial port module includes MAX232 chip and four 104 capacitors, four 104 capacitors difference
For capacitor C1, capacitor C2, capacitor C3 and capacitor C4, No. 1 pin and No. 3 pins of the MAX232 chip are respectively with capacitor C1's
Both ends connection, No. 4 pins and No. 5 pins of the MAX232 chip are connect with the both ends of capacitor C2 respectively, the MAX232 core
No. 2 pins and No. 16 pins of piece are connect with the both ends of capacitor C3 respectively, No. 15 pins and No. 6 pins of the MAX232 chip
It is connect respectively with the both ends of capacitor C4 ,+3.3V the power supply that No. 16 pins and external power source circuit of the MAX232 chip provide
Connection, No. 6 pins ground connection of the MAX232 chip, No. 10 pins of the MAX232 chip are DSP data sending terminal, described
No. 10 pins of MAX232 chip are connect with No. 28 pins of main control chip 2, and No. 9 pins of the MAX232 chip are DSP number
According to receiving end, No. 9 pins of the MAX232 chip connect with No. 24 pins of main control chip 2 and realize and main control chip 2 pairs
To communication, No. 8 pins of the MAX232 chip are PC data receiver, and No. 8 pins of the MAX232 chip pass through serial ports
Line is connect with No. 3 endpoints of the RS232 interface at the end PC 4, and No. 7 pins of the MAX232 chip are PC data sending terminal, described
No. 7 pins of MAX232 chip are connect and are realized two-way with the end PC 4 with No. 7 endpoints of the RS232 interface at the end PC 4 by Serial Port Line
Communication.
The working principle of the utility model are as follows: primary coil current-limiting resistance of three-phase voltage signal input signal reduction voltage circuit 5
R1 passes through Hall voltage sensor later, exports from No. 6 pins of Hall voltage sensor, and voltage is reduced to original 0.007
Times, the resistance R1 of the voltage signal input signal shaping circuit 6 after decompression, after the shaping of Noninverting summing operation circuit summation
It is exported from No. 1 pin of LM324 chip, inputs the cathode of the diode DQ1 of AD protection circuit 7 and the sun of diode DQ2 later
Pole junction, at this time output voltage signal control can satisfy main control chip 2 (TMS320F28035 chip) in (0-3.3) V
The position 16X12 AD conversion end require.
By the input terminal of voltage signal input main control chip 2 (TMS320F28035 chip) of AD protection circuit 7, pass through
The position the 16X12 AD conversion end of main control chip 2 is converted to the digital signal for meeting the requirement of main control chip 2, and by main control chip 2
Frequency detecting algorithm, pile defection algorithm, misphase detection algorithm and RMS to DC algorithm calculate and fault detection, judges whether
Faulty exception.
Main control chip 2 will test what the data transfer after calculating and being shown in remotely controlled by 3 input terminal of serial port module
On 4 computer screen of the end PC, if there is failure exception, there is alarm signal in computer screen, while the query demand order at the end PC 4 can
Main control chip 2 is inputted by serial port module 3, main control chip 2 calculates by program and shows 4 information needed of the end PC in 4 electricity of the end PC
On brain screen.
The above is only the preferred embodiment of the utility model, not imposes any restrictions to the utility model, all
According to the utility model technical spirit any simple modification, change and equivalent structure transformation to the above embodiments, still
Belong in the protection scope of technical solutions of the utility model.
Claims (7)
1. a kind of three-phase voltage remotely monitors and protection circuit, it is characterised in that: including signal conditioning module (1), main control chip
(2), serial port module (3) and the end PC (4), the output end of the signal conditioning module (1) and the input terminal of main control chip (2) connect
It connects, the main control chip (2) is bi-directionally connected with serial port module (3), and the serial port module (3) is bi-directionally connected with the end PC (4)；It is described
Signal conditioning module (1) includes signal reduction voltage circuit (5), signal transformation circuit (6) and AD protection circuit (7), the signal drop
The output end of volt circuit (5) is connect with the input terminal of signal transformation circuit (6), the output end of the signal transformation circuit (6) with
AD protects the input terminal connection of circuit (7), and the output end of AD protection circuit (7) is connect with the input terminal of main control chip (2).
2. a kind of three-phase voltage described in accordance with the claim 1 remotely monitors and protection circuit, it is characterised in that: the end PC
It (4) is the personal computer for being equipped with RS232 interface and three-phase voltage data monitoring and obstruction warning status inquiry being carried out.
3. a kind of three-phase voltage remotely monitors and protection circuit according to claim 2, it is characterised in that: the master control core
Piece (2) is that model is TMS320F28035 and the dsp chip containing 16X12 AD conversion ends, No. 28 of the main control chip (2)
Pin is data receiver, and No. 24 pins of the main control chip (2) are data sending terminal.
4. a kind of three-phase voltage described in accordance with the claim 3 remotely monitors and protection circuit, it is characterised in that: the signal drop
Volt circuit (5) includes primary coil current-limiting resistance R1, the Hall voltage sensor for measuring resistance R2 and model LV25-P, the original
The resistance value of coil current-limiting resistance R1 be 12K Ω, it is described measurement resistance R2 resistance value be 33 Ω, the 1 of the Hall voltage sensor
Number pin is connect with one end of primary coil current-limiting resistance R1, and the other end of primary coil current-limiting resistance R1 is signal input part,
No. 2 pins of the Hall voltage sensor are grounded, No. 3 pins of the Hall voltage sensor and one end of measurement resistance R2
Connection, the other end ground connection of the measurement resistance R2, No. 4 pins and external power source circuit of the Hall voltage sensor provide
The connection of+12V power supply, No. 5 pins of the Hall voltage sensor connect with -12V the power supply that external power source circuit provides, institute
No. 3 pins for stating Hall voltage sensor are signal output end, No. 3 pins of the Hall voltage sensor and signal shaping electricity
The input terminal on road (6) connects.
5. a kind of three-phase voltage remotely monitors and protection circuit according to claim 4, it is characterised in that: the signal is whole
Shape circuit (6) includes resistance R1, resistance R2, resistance R3 and the electricity that LM324 chip, a potentiometer W1 and four resistance values are 1K
R4 is hindered, No. 1 end of the potentiometer W1 is connect with+3.3V the power supply that external power source circuit provides, No. 2 ends of the potentiometer W1
Ground connection, No. 3 ends of the potentiometer W1 connect with one end of resistance R2, the other end of the resistance R2 and one end of resistance R1 and
No. 3 pins of LM324 chip are all connected with, and No. 1 pin and No. 2 pins of the LM324 chip are connect with resistance R4, described
No. 2 pins of LM324 chip are connect with one end of resistance R3, the other end ground connection of the resistance R3, and the 4 of the LM324 chip
Number pin is connect with+15V the power supply that external power source circuit provides, and the other end of the resistance R1 is signal input part, the electricity
No. 3 pins of the other end and Hall voltage sensor that hinder R1 connect, and No. 1 pin of the LM324 chip is signal output end,
No. 1 pin of the LM324 chip is connect with the input terminal of AD protection circuit (7).
6. a kind of three-phase voltage remotely monitors and protection circuit according to claim 5, it is characterised in that: the AD protection
Circuit (7) includes diode DQ1 and diode DQ2, the plus earth of the diode DQ1, the cathode of the diode DQ1 with
The anode of diode DQ2 connects, and the cathode of the diode DQ2 is connect with+3.3V the power supply that external power source circuit provides, described
No. 1 pin and main control chip (2) of the cathode of diode DQ1 and the anode junction of diode DQ2 and LM324 chip
16X12 AD conversion ends are all connected with.
7. a kind of three-phase voltage remotely monitors and protection circuit according to claim 6, it is characterised in that: the serial ports mould
Block (3) includes MAX232 chip and four 104 capacitors, four 104 capacitors be respectively capacitor C1, capacitor C2, capacitor C3 and
Capacitor C4, No. 1 pin and No. 3 pins of the MAX232 chip are connect with the both ends of capacitor C1 respectively, the MAX232 chip
No. 4 pins and No. 5 pins connect respectively with the both ends of capacitor C2, No. 2 pins of the MAX232 chip and No. 16 pins point
It not being connect with the both ends of capacitor C3, No. 15 pins and No. 6 pins of the MAX232 chip are connect with the both ends of capacitor C4 respectively,
No. 16 pins of the MAX232 chip are connect with+3.3V the power supply that external power source circuit provides, and No. 6 of the MAX232 chip
Pin ground connection, No. 10 pins of the MAX232 chip are DSP data sending terminal, No. 10 pins of the MAX232 chip and master
No. 28 pins connection of chip (2) is controlled, No. 9 pins of the MAX232 chip are DSP data receiver, the MAX232 chip
No. 9 pins connect with No. 24 pins of main control chip (2) and realize with main control chip (2) two-way communication, the MAX232 core
No. 8 pins of piece are PC data receiver, and No. 8 pins of the MAX232 chip are connect by Serial Port Line and the RS232 of the end PC (4)
No. 3 endpoints connection of mouth, No. 7 pins of the MAX232 chip are PC data sending terminal, No. 7 pins of the MAX232 chip
It is connect and is realized and the end PC (4) two-way communication with No. 7 endpoints of the RS232 interface of the end PC (4) by Serial Port Line.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201822006699.9U CN209056980U (en) | 2018-11-30 | 2018-11-30 | A kind of three-phase voltage remotely monitors and protection circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201822006699.9U CN209056980U (en) | 2018-11-30 | 2018-11-30 | A kind of three-phase voltage remotely monitors and protection circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN209056980U true CN209056980U (en) | 2019-07-02 |
Family
ID=67054616
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201822006699.9U Expired - Fee Related CN209056980U (en) | 2018-11-30 | 2018-11-30 | A kind of three-phase voltage remotely monitors and protection circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN209056980U (en) |
-
2018
- 2018-11-30 CN CN201822006699.9U patent/CN209056980U/en not_active Expired - Fee Related
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Granted publication date: 20190702 Termination date: 20201130 |