CN111693904B - Terminal box access line sequence detection circuit and detection method using same - Google Patents
Terminal box access line sequence detection circuit and detection method using same Download PDFInfo
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- CN111693904B CN111693904B CN202010356424.7A CN202010356424A CN111693904B CN 111693904 B CN111693904 B CN 111693904B CN 202010356424 A CN202010356424 A CN 202010356424A CN 111693904 B CN111693904 B CN 111693904B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/66—Testing of connections, e.g. of plugs or non-disconnectable joints
- G01R31/67—Testing the correctness of wire connections in electric apparatus or circuits
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
- G01R15/20—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using galvano-magnetic devices, e.g. Hall-effect devices, i.e. measuring a magnetic field via the interaction between a current and a magnetic field, e.g. magneto resistive or Hall effect devices
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Abstract
The invention discloses a circuit for detecting the access sequence of an end button box, wherein three anti-electricity-theft CTs are arranged in the end button box and respectively correspond to an A phase, a B phase and a C phase, the detection circuit comprises an MCU control circuit, a current sampling circuit, an anti-electricity-theft resonance sampling circuit and an AC/DC conversion circuit, the output end of the alternating current/direct current conversion circuit is connected to one input end of each phase of electricity stealing prevention CT through a power resistor, the current signal output end of each phase of electricity stealing prevention CT is connected to the input end of the current sampling circuit, the electricity stealing prevention signal output end of each phase of electricity stealing prevention CT is connected to the input end of the electricity stealing prevention resonance sampling circuit, the output ends of the current sampling circuit and the electricity larceny prevention resonance sampling circuit are both connected to the input end of the MCU control circuit, and a switch element which is controlled to be switched on and off by the MCU control circuit is connected between the two input ends of each phase of electricity larceny prevention CT. A current and anti-electricity-theft access line sequence detection method using the detection circuit is also disclosed.
Description
Technical Field
The invention relates to the field of electronic measurement, in particular to a terminal box access line sequence detection circuit and a detection method using the same.
Background
An electric power terminal product, such as an electric energy meter, is a metering tool for metering electric energy, and a terminal box is an important component of the electric energy meter. In the power industry, southern power grids require the function of electricity larceny prevention for terminal products, and most of the electricity larceny prevention structures used at present are electricity larceny prevention CTs (current transformers). The primary side of the anti-electricity-theft CT used by the southern power grid terminal is welded on a current terminal of a terminal box, namely the terminal box and the anti-electricity-theft CT are integrated, and a current terminal and an anti-electricity-theft terminal are led out from the secondary side of each phase of CT. Referring to fig. 1, the primary side on the left side has a primary coil L1, the secondary side on the right side has a secondary coil L2, the primary coil L1 is welded on the current terminal of the terminal box, and an inductance L for preventing electricity stealing is added on the secondary side. Therefore, the terminal box has 3 paths of current access (output through L2) and 3 paths of electricity stealing prevention access (output through L).
The terminal box of the three-phase electric energy meter disclosed in the Chinese patent with the application number of 201611264785.9 comprises a terminal box, a relay and a mutual inductor; the terminal button box is provided with an A-phase wire inlet end, a B-phase wire inlet end, a C-phase wire inlet end, an A-phase wire outlet end, a B-phase wire outlet end and a C-phase wire outlet end; one side of the terminal button box is provided with an accommodating box, and the relay and the mutual inductor are arranged in the accommodating box as an integrated structure and are connected with an A-phase wire inlet end, a B-phase wire inlet end, a C-phase wire inlet end, an A-phase wire outlet end, a B-phase wire outlet end and a C-phase wire outlet end of the terminal button box.
When the terminal product is produced, whether the line sequence accessed by the anti-electricity-theft CT is correct or not is required to be detected, and welding manufacture is carried out on the access terminal on the premise of ensuring correct line sequence access.
The detection of the access line sequence in the existing production workshop is manually detected, and the anti-electricity-theft 3-way access lines are white and have no color distinction, so that the manual detection efficiency is low, and manual stations are occupied. With the intense competition of enterprises, automated production is a necessary skill for the survival of enterprises, and therefore, a device and a method capable of automatic detection are urgently needed.
Disclosure of Invention
The first technical problem to be solved by the present invention is to provide a terminal box access line sequence detection circuit, which can realize automatic detection of an access line sequence and improve detection efficiency, aiming at the defects existing in the prior art.
The second technical problem to be solved by the present invention is to provide a method for detecting a current access line sequence by using the above detection circuit.
The third technical problem to be solved by the present invention is to provide a method for detecting an access line sequence for preventing electricity stealing by using the above detection circuit.
The technical scheme adopted by the invention for solving the first technical problem is as follows: the utility model provides an end button box access line preface detection circuitry, be provided with three anti-electricity-theft CT in the end button box, correspond A looks, B looks and C looks respectively, its characterized in that: the detection circuit comprises an MCU control circuit, a current sampling circuit, an electricity larceny prevention resonance sampling circuit and an alternating current/direct current conversion circuit, wherein the output end of the alternating current/direct current conversion circuit is connected to one input end of each phase of electricity larceny prevention CT through a power resistor, the current signal output end of each phase of electricity larceny prevention CT is connected to the input end of the current sampling circuit, the electricity larceny prevention signal output end of each phase of electricity larceny prevention CT is connected to the input end of the electricity larceny prevention resonance sampling circuit, the output ends of the current sampling circuit and the electricity larceny prevention resonance sampling circuit are both connected to the input end of the MCU control circuit, and a switch element which is controlled to be switched on and switched off by the MCU control circuit is connected between the two input ends of each phase of electricity larceny prevention CT.
Preferably, the electricity stealing prevention CT has a structure in which a primary side of each phase electricity stealing prevention CT has a primary coil as an input terminal of the electricity stealing prevention CT, and a secondary side of each phase electricity stealing prevention CT has a secondary coil as a current signal output terminal and an inductor as an output terminal of the electricity stealing prevention signal.
Further, in order to facilitate sampling, the current sampling circuit is connected with the secondary coil in series, and the electricity larceny prevention resonance sampling circuit is connected with the inductor in parallel.
Preferably, the power resistor comprises a first resistor corresponding to the phase-A electricity stealing prevention CT, a second resistor corresponding to the phase-B electricity stealing prevention CT, and a third resistor corresponding to the phase-C electricity stealing prevention CT.
Preferably, in order to facilitate the control of the on-off between the input ends of the anti-electricity-theft CT, a relay which is controlled by the MCU control circuit to be turned on and off and serves as a switching element is connected in parallel to the two input ends of each phase of the anti-electricity-theft CT.
Preferably, the relay includes a first relay connected in parallel between two input terminals of the phase a electricity stealing prevention CT, a second relay connected in parallel between two input terminals of the phase B electricity stealing prevention CT, and a third relay connected in parallel between two input terminals of the phase C electricity stealing prevention CT.
The technical scheme adopted by the invention for solving the second technical problem is as follows: a current access sequence detection method utilizing the terminal button box access sequence detection circuit is characterized in that: the method comprises the following steps:
1) Firstly, the MCU control circuit controls each switch element to be opened, so that an open circuit is formed between two input ends of each phase of the anti-electricity-theft CT, and the alternating current/direct current conversion circuit inputs current to the input end of each phase of the anti-electricity-theft CT;
2) the current sampling circuit processes the sampled current signal of the output end of each phase of the anti-electricity-theft CT and inputs the processed current signal into the MCU control circuit, and the MCU control circuit judges whether the access line sequence of each phase is correct according to the received current signal:
2.1) judging whether the A-phase current sampling value received by the MCU control circuit is equal to the current value input to the A-phase electricity larceny prevention CT, if so, indicating that the current access line sequence of the A-phase electricity larceny prevention CT is correct, and finishing the detection; if not, indicating that the current access line sequence of the A-phase electricity larceny prevention CT is wrong, and ending the detection;
2.2) judging whether the sampling value of the phase B current received by the MCU control circuit is equal to the current value input to the phase B electricity stealing prevention CT, if so, indicating that the current access line sequence of the phase B electricity stealing prevention CT is correct, and finishing the detection; if not, the current access line sequence of the B-phase electricity larceny prevention CT is wrong, and the detection is finished;
2.3) judging whether the C-phase current sampling value received by the MCU control circuit is equal to the current value input to the C-phase electricity larceny prevention CT, if so, indicating that the current access line sequence of the C-phase electricity larceny prevention CT is correct, and finishing the detection; if not, the current access line sequence of the C-phase electricity larceny prevention CT is wrong, and the detection is finished.
In order to facilitate the MCU control circuit to determine the current sampling value, the resistance values of the power resistors connected to the output terminals of the anti-electricity-theft CT and ac/dc conversion circuits of each phase are different from each other, so that the current values input to the anti-electricity-theft CT of each phase are different from each other.
The technical scheme adopted by the invention for solving the third technical problem is as follows: the anti-electricity-theft access line sequence detection method for the terminal button box access line sequence detection circuit is characterized in that: the method comprises the following steps:
1) the MCU control circuit controls the switch elements to be opened, so that an open circuit is formed between two input ends of each phase of electricity stealing prevention CT, the AD value of each phase of electricity stealing prevention CT sampling voltage is respectively tested and stored as KA, KB and KC;
2) the MCU control circuit controls a switch element connected in parallel with the input end of the phase-A electricity stealing prevention CT to be closed, so that two input ends of the phase-A electricity stealing prevention CT are short-circuited, the sampled anti-theft electric signals of the phase-A electricity stealing prevention CT are processed by the anti-electricity stealing resonance sampling circuit (5) and then input into the MCU control circuit (1), the MCU control circuit (1) reads the AD value DA of the phase-A electricity stealing prevention electric signals at the moment, whether DA > KA is established or not is judged, if yes, the anti-electricity stealing access line sequence of the phase-A electricity stealing prevention CT is judged to be not wrong, and the step 3 is carried out; if not, judging that the electricity stealing prevention access line sequence of the phase A electricity stealing prevention CT is wrong, and entering the step 3);
3) The MCU control circuit controls a switch element connected in parallel with the input end of the B-phase electricity stealing prevention CT to be closed, so that the two input ends of the B-phase electricity stealing prevention CT are short-circuited, the sampled electricity stealing prevention signal of the B-phase electricity stealing prevention CT is processed by the electricity stealing prevention resonance sampling circuit and then is input into the MCU control circuit, the MCU control circuit reads the AD value DB of the B-phase electricity stealing prevention signal at the moment, whether DB > KB is established or not is judged, if yes, the electricity stealing prevention access line sequence of the B-phase electricity stealing prevention CT is judged to have no error, and the step 4 is carried out; if not, judging that the electricity larceny prevention access line sequence of the CT for preventing electricity larceny of the phase B is wrong, and entering the step 4);
4) the MCU control circuit (1) controls a switch element connected in parallel with the input end of the C-phase electricity stealing prevention CT to be closed, so that two input ends of the C-phase electricity stealing prevention CT are short-circuited, the sampled electricity stealing prevention signal of the C-phase electricity stealing prevention CT is processed by the electricity stealing prevention resonance sampling circuit and then is input into the MCU control circuit, the MCU control circuit (1) reads an AD value DC of the C-phase electricity stealing prevention signal at the moment, whether DC & gt KC is established or not is judged, if yes, the electricity stealing prevention access line sequence of the C-phase electricity stealing prevention CT is judged to be not wrong, and the detection is finished; if not, judging that the electricity stealing prevention access line sequence of the C-phase electricity stealing prevention CT is wrong, and finishing the detection.
Preferably, the anti-electricity-theft resonant sampling circuit and the anti-electricity-theft signal output end of the anti-electricity-theft CT form a parallel RLC resonant circuit so as to collect voltage signals at two ends of the R as anti-electricity-theft signals.
Compared with the prior art, the invention has the advantages that: the current sampling circuit for sampling the output current of the anti-electricity-theft CT and the anti-electricity-theft resonance sampling circuit for sampling the anti-electricity-theft signal output by the anti-electricity-theft CT are arranged, and the MCU control circuit can automatically judge whether the access line sequence is correct or not by utilizing the sampling signal, so that the detection process can be saved, the labor cost can be saved, and the detection efficiency of the access line sequence can be improved.
Drawings
FIG. 1 is a prior art CT electrical schematic diagram for preventing electricity theft;
FIG. 2 is a block diagram of an access line sequence detection tool according to an embodiment of the present invention;
FIG. 3 is a flowchart illustrating CT access sequence detection for a button box according to an embodiment of the present invention;
fig. 4 is a flow chart of detecting the terminal box anti-electricity-theft access line sequence according to the embodiment of the invention.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar functions.
In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present invention and to simplify the description, but are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and that the directional terms are used for purposes of illustration and are not to be construed as limiting, for example, because the disclosed embodiments of the present invention may be oriented in different directions, "lower" is not necessarily limited to a direction opposite to or coincident with the direction of gravity. Furthermore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.
Referring to fig. 2, the terminal box access line sequence detection circuit includes an MCU control circuit 1, a first relay 21, a second relay 22, a third relay 23, three power resistors (a first resistor 31, a second resistor 32, and a third resistor 33), a current sampling circuit 4, an electricity larceny prevention resonance sampling circuit 5, and an ac/dc conversion circuit 6. The detection circuit is electrically connected with a terminal box 7 with anti-electricity-theft CTs (three anti-electricity-theft CTs, corresponding to three phases), and the circuit principle of each phase of anti-electricity-theft CT is the same as that of the prior art, as shown in figure 1.
The ac/dc conversion circuit 6 may be, for example, a transformer, connected to the commercial power to convert 220V ac power into 2V dc power. The output end of the ac/dc conversion circuit 6 connects the current signal to one end of the primary coil L1 on the primary side of the anti-fraudulent use CT of electricity of the terminal box 7 through three power resistors, the resistance value of the first resistor 31 is preferably 4 Ω, the resistance value of the second resistor 32 is preferably 2 Ω, and the resistance value of the third resistor 33 is preferably 1 Ω. The a-phase current, the B-phase current, and the C-phase current are inputted through the first resistor 31, the second resistor 32, and the third resistor 33, respectively, and are outputted from the other end of the primary winding L1 on the primary side of the electricity stealing prevention CT of the terminal box 7 to the ac/dc conversion circuit 6.
One end of a secondary coil L2 on the secondary side of the electricity larceny prevention CT of the terminal box 7 is electrically connected to the current sampling circuit 4, so that a current signal is connected to the current sampling circuit 4, processed by the current sampling circuit 4 and then input to the input end of the MCU control circuit 1. The two ends of the anti-electricity-theft inductor L of the anti-electricity-theft CT of the terminal box 7 are electrically connected to the anti-electricity-theft resonant sampling circuit 5, so that the anti-electricity-theft signal is accessed to the anti-electricity-theft resonant sampling circuit 5, and the resonant signal is processed by the anti-electricity-theft resonant sampling circuit 5 and then input to the input end of the MCU control circuit 1. The MCU control circuit 1 determines whether the current access line sequence and the electricity larceny prevention access line sequence are correct according to the input current AD value (the value obtained by digitizing the analog circuit signal) and the electricity larceny prevention AD value (the value obtained by digitizing the analog circuit signal). Meanwhile, the current sampling circuit 4 and the electricity larceny prevention resonance sampling circuit 5 can also output three-phase signals to return to the secondary side of the electricity larceny prevention CT of the terminal box 7.
The current sampling circuit 4 can adopt the existing current sampling circuit, and is connected with the secondary coil L2 of each phase of anti-electricity-theft CT in series, and the anti-electricity-theft resonance sampling circuit 5 can adopt the existing voltage sampling circuit, in the embodiment, the anti-electricity-theft resonance sampling circuit 5 selects the matched resistor and capacitor according to the parallel RLC resonance circuit principle, namely, the resistor and capacitor of the anti-electricity-theft resonance sampling circuit 5 are connected in series and then connected in parallel at two ends of the anti-electricity-theft inductor L to form the RLC resonance circuit, so that the frequency f is 2 pi omega, and when in resonance, the current is minimum, and the resistance is maximum. Because the short circuit and the open circuit of the primary coil L1 on the primary side can cause the change of inductance L of the anti-electricity-theft inductor on the secondary side, the inductance is large when the inductor is open (the current is maximum, the resistance is minimum, and the sampling voltage at two ends of the resistor is minimum), and the inductance is low when the inductor is short (the current is minimum, the resistance is maximum, and the sampling voltage at two ends of the resistor is maximum when no inductor exists). Therefore, the sampling value of the anti-electricity-theft resonant sampling circuit 5 during short circuit is obviously much larger than that of the anti-electricity-theft resonant sampling circuit 5 during open circuit, so as to judge whether the access line sequence is correct.
One relay is connected in parallel to the access terminal (both ends of the primary coil L1) of each phase current, that is, the first relay 21 is connected in parallel to the terminal of the a-phase current input, the second relay 22 is connected in parallel to the terminal of the B-phase current input, and the third relay 23 is connected in parallel to the terminal of the C-phase current input. Each relay is electrically connected to the output end of the MCU control circuit 1, and the on-off state of each relay is controlled by the MCU control circuit 1. Alternatively, other switching elements, such as contactors, electronic switches, air switches, etc., may be used in place of the relays.
The current access line sequence can be detected and judged in a parallel mode through different input currents, time is saved, the inductance value of the electricity larceny prevention inductor L is fixed, the resonance frequency is fixed, and the detection and judgment are carried out in a serial mode.
Specifically, referring to fig. 3, the detection process of the current access line sequence includes the following steps:
1) initially, the MCU control circuit 1 controls the three relays to be turned on, and at this time, the two ends of the primary coil L1 are open, and the ac/dc conversion circuit 6 can input current to the primary coil L1 of the electricity larceny prevention CT of the terminal box 7, where the a-phase input current is 0.5A (first current value), the B-phase input current is 1A (second current value), and the C-phase input current is 2A (third current value), and the current values are determined according to the resistances of the three power resistors;
2) the current sampling circuit 4 processes the sampled current signal of each phase of the secondary coil L2 on the secondary side, and inputs the processed current signal into the MCU control circuit 1, and the MCU control circuit 1 determines whether the access line sequence of each phase is correct according to the received current signal:
2.1) judging whether the sampling value of the A-phase current received by the MCU control circuit 1 is equal to 0.5A (first current value), if so, indicating that the access line sequence of the A-phase current (secondary coil L2 of the electricity stealing prevention CT) is correct, and finishing the detection; if not, the access error of the A-phase CT sampling line is indicated, and the detection is finished;
2.2) judging whether the sampling value of the phase B current received by the MCU control circuit 1 is equal to 1A (second current value), if so, indicating that the access line sequence of the phase B current (secondary coil L2 of the electricity larceny prevention CT) is correct, and finishing the detection; if not, the access error of the B-phase CT sampling line is indicated, and the detection is finished;
2.3) judging whether the C-phase current sampling value received by the MCU control circuit 1 is equal to 2A (third current value), if so, indicating that the access line sequence of the C-phase current (secondary coil L2 of the electricity larceny prevention CT) is correct, and finishing the detection; if not, the access error of the C-phase CT sampling line is indicated, and the detection is finished.
Referring to fig. 4, the procedure for detecting the access line sequence of the anti-electricity-theft CT access includes the following steps:
1) firstly, the MCU control circuit 1 controls three relays to be opened, the AD values of three-phase electricity stealing prevention CT (three circuits respectively corresponding to an A phase, a B phase and a C phase) sampling voltages are respectively tested and stored as KA, KB and KC, and at the moment, two ends of a primary coil L1 of each phase are opened;
2) the MCU control circuit 1 controls the first relay 21 to be closed, so that a primary coil L1 on the primary side of the anti-electricity-theft CT of the phase A is short-circuited, the anti-electricity-theft resonant sampling circuit 5 processes the anti-electricity-theft signal of the phase A at the moment and inputs the processed signal into the MCU control circuit 1, the MCU control circuit 1 reads an AD value DA of the anti-electricity-theft signal of the phase A at the moment, whether DA > KA is established or not is judged, if yes, the fact that the access line sequence of the anti-electricity-theft CT of the phase A (an inductance L of the anti-electricity-theft CT) is not wrong is judged, and the step 3 is carried out; if not, judging that the line sequence of the phase A electricity stealing prevention (the inductance L of the electricity stealing prevention CT) access line is wrong, and entering the step 3);
3) Controlling the second relay 22 to close, so that a primary coil L1 on the primary side of the anti-electricity-theft CT of the B phase is short-circuited, the anti-electricity-theft resonant sampling circuit 5 processes the anti-electricity-theft signal of the B phase at the moment and inputs the processed signal into the MCU control circuit 1, the MCU control circuit 1 reads an AD value DB of the anti-electricity-theft signal of the B phase at the moment, whether DB > KB is established or not is judged, if yes, the access line sequence of the anti-electricity-theft CT of the B phase (an inductance L of the anti-electricity-theft CT) is judged to be error, and the step 4 is carried out; if not, judging that the access line sequence of the B-phase electricity larceny prevention (the inductor L of the electricity larceny prevention CT) is wrong, and entering the step 4);
4) controlling the third relay 23 to be closed, so that a primary coil L1 on the primary side of the anti-electricity-theft CT of the C phase is short-circuited, the anti-electricity-theft resonant sampling circuit 5 processes the anti-electricity-theft signal of the C phase at the moment and inputs the processed signal into the MCU control circuit 1, the MCU control circuit 1 reads an AD value DC of the anti-electricity-theft signal of the C phase at the moment and judges whether DC > KC is established, if so, the C phase anti-electricity-theft (an inductance L of the anti-electricity-theft CT) access line sequence is judged to have no error, and the detection is finished; if not, judging that the access line sequence of the C-phase electricity stealing prevention electricity (the inductance L of the electricity stealing prevention CT) is wrong, and finishing the detection.
In the above detection process, after the MCU control circuit 1 detects that the access line sequence is correct or incorrect, the detection result can be output in different manners, such as lighting color, sound, or displaying on a display screen.
Claims (10)
1. The utility model provides an end button box access line preface detection circuitry, be provided with three anti-electricity-theft CT in the end button box, correspond A looks, B looks and C looks respectively, its characterized in that: the detection circuit comprises an MCU control circuit (1), a current sampling circuit (4), an electricity larceny prevention resonance sampling circuit (5) and an alternating current/direct current conversion circuit (6), wherein the output end of the alternating current/direct current conversion circuit (6) is connected to one input end of each phase of electricity larceny prevention CT through a power resistor, the current signal output end of each phase of electricity larceny prevention CT is connected to the input end of the current sampling circuit (4), the electricity larceny prevention signal output end of each phase of electricity larceny prevention CT is connected to the input end of the electricity larceny prevention resonance sampling circuit (5), the output ends of the current sampling circuit (4) and the electricity larceny prevention resonance sampling circuit (5) are both connected to the input end of the MCU control circuit (1), and a switch element which is controlled to be switched on or switched off by the MCU control circuit (1) is connected between the two input ends of each phase of the electricity larceny prevention CT.
2. The terminal box access line sequence detection circuit of claim 1, wherein: the primary side of each phase electricity stealing prevention CT is provided with a primary coil (L1) as an electricity stealing prevention CT input end, and the secondary side of each phase electricity stealing prevention CT is provided with a secondary coil (L2) as a current signal output end and an inductor (L) as an electricity stealing prevention signal output end.
3. The terminal box access sequence detection circuit according to claim 2, characterized in that: the current sampling circuit (4) is connected with the secondary coil (L2) in series, and the electricity larceny prevention resonance sampling circuit (5) is connected with the inductor (L) in parallel.
4. The terminal box access line sequence detection circuit of claim 1, wherein: the power resistor comprises a first resistor (31) corresponding to the phase-A electricity stealing prevention CT, a second resistor (32) corresponding to the phase-B electricity stealing prevention CT and a third resistor (33) corresponding to the phase-C electricity stealing prevention CT.
5. The terminal box access line sequence detection circuit of claim 1, wherein: two input ends of each phase of the anti-electricity-theft CT are connected in parallel with a relay which is controlled by the MCU control circuit (1) to be switched on and off and is used as a switching element.
6. The terminal box access sequence detection circuit according to claim 5, characterized in that: the relay comprises a first relay (21) connected between two input ends of the A-phase electricity stealing prevention CT in parallel, a second relay (22) connected between two input ends of the B-phase electricity stealing prevention CT in parallel, and a third relay (23) connected between two input ends of the C-phase electricity stealing prevention CT in parallel.
7. A current access sequence detection method using the terminal box access sequence detection circuit according to any one of claims 1 to 6, characterized in that: the method comprises the following steps:
1) Firstly, the MCU control circuit (1) controls each switch element to be opened, so that an open circuit is formed between two input ends of each phase of electricity stealing prevention CT, and the alternating current/direct current conversion circuit (6) inputs current to the input end of each phase of electricity stealing prevention CT;
2) the current sampling circuit (4) processes the sampled current signal of the output end of each phase of the anti-electricity-theft CT, and then inputs the processed current signal into the MCU control circuit (1), and the MCU control circuit (1) judges whether the access line sequence of each phase is correct according to the received current signal:
2.1) judging whether the sampling value of the A-phase current received by the MCU control circuit (1) is equal to the current value input to the A-phase electricity larceny prevention CT or not, if so, indicating that the current access line sequence of the A-phase electricity larceny prevention CT is correct, and finishing the detection; if not, the current access line sequence of the A-phase electricity larceny prevention CT is wrong, and the detection is finished;
2.2) judging whether the sampling value of the phase B current received by the MCU control circuit (1) is equal to the current value input to the phase B electricity stealing prevention CT, if so, indicating that the current access line sequence of the phase B electricity stealing prevention CT is correct, and finishing the detection; if not, the current access line sequence of the B-phase electricity larceny prevention CT is wrong, and the detection is finished;
2.3) judging whether the C-phase current sampling value received by the MCU control circuit (1) is equal to the current value input to the C-phase electricity stealing prevention CT, if so, indicating that the current access line sequence of the C-phase electricity stealing prevention CT is correct, and finishing the detection; if not, the current access line sequence of the C-phase electricity larceny prevention CT is wrong, and the detection is finished.
8. The method for detecting the current access sequence of the terminal box access sequence detection circuit according to claim 7, wherein: the resistance values of the power resistors connected with the output ends of the anti-electricity-theft CT and the AC/DC conversion circuit (6) of each phase are different, so that the current values input to the anti-electricity-theft CT of each phase are different.
9. An electricity-stealing prevention access sequence detection method using the terminal box access sequence detection circuit according to any one of claims 1 to 6, characterized in that: the method comprises the following steps:
1) the MCU control circuit (1) controls each switch element to be opened, so that an open circuit is formed between two input ends of each phase of electricity stealing prevention CT, the AD value of each phase of electricity stealing prevention CT sampling voltage is respectively tested and stored as KA, KB and KC;
2) the method comprises the following steps that the MCU control circuit (1) controls a switch element connected in parallel with the input end of the phase-A electricity stealing prevention CT to be closed, so that the two input ends of the phase-A electricity stealing prevention CT are in short circuit, the sampled electricity stealing prevention signal of the phase-A electricity stealing prevention CT is processed by the electricity stealing prevention resonance sampling circuit (5) and then is input into the MCU control circuit (1), the MCU control circuit (1) reads the AD value DA of the current phase-A electricity stealing prevention signal, whether DA > KA is established or not is judged, if yes, the electricity stealing prevention access line sequence of the phase-A electricity stealing prevention CT is judged to be not wrong, and the step 3 is carried out; if not, judging that the electricity stealing prevention access line sequence of the phase A electricity stealing prevention CT is wrong, and entering the step 3);
3) The MCU control circuit (1) controls a switch element connected in parallel with the input end of the B-phase electricity stealing prevention CT to be closed, so that the two input ends of the B-phase electricity stealing prevention CT are short-circuited, the sampled electricity stealing prevention signal of the B-phase electricity stealing prevention CT is processed by the electricity stealing prevention resonance sampling circuit (5) and then is input into the MCU control circuit (1), the MCU control circuit (1) reads an AD value DB of the B-phase electricity stealing prevention signal at the moment, whether DB > KB is established or not is judged, if yes, the electricity stealing prevention access line sequence of the B-phase electricity stealing prevention CT is judged to be not wrong, and the step 4 is entered; if not, judging that the electricity larceny prevention access line sequence of the CT for preventing electricity larceny of the phase B is wrong, and entering the step 4);
4) the MCU control circuit (1) controls a switch element connected in parallel with the input end of the C-phase electricity stealing prevention CT to be closed, so that the two input ends of the C-phase electricity stealing prevention CT are short-circuited, the sampled electricity stealing prevention electric signal of the C-phase electricity stealing prevention CT is processed by the electricity stealing prevention resonance sampling circuit (5) and then is input into the MCU control circuit (1), the MCU control circuit (1) reads the AD value DC of the C-phase electricity stealing prevention electric signal at the moment, whether DC & gt KC is established or not is judged, if yes, the electricity stealing prevention access line sequence of the C-phase electricity stealing prevention CT is judged to be wrong, and the detection is finished; if not, judging that the electricity stealing prevention access line sequence of the C-phase electricity stealing prevention CT is wrong, and finishing the detection.
10. The method for detecting the anti-electricity-theft access sequence of the terminal box access sequence detection circuit according to claim 9, wherein: the anti-electricity-theft resonance sampling circuit (5) and the anti-electricity-theft signal output end of the anti-electricity-theft CT form a parallel RLC resonance circuit.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201373892Y (en) * | 2009-02-23 | 2009-12-30 | 凯迈(洛阳)电子有限公司 | Real-time detection circuit for preventing electricity-stealing in current method |
| CN105203905A (en) * | 2015-09-21 | 2015-12-30 | 国家电网公司 | Electric energy measuring secondary circuit rapid line inspection instrument |
| CN106443304A (en) * | 2016-11-07 | 2017-02-22 | 北京博纳电气股份有限公司 | Method for detecting secondary side loop state of once metering CT on ammeter exterior and detection device |
| CN206583984U (en) * | 2017-01-26 | 2017-10-24 | 国家电网公司 | A kind of anti-electricity-theft device based on transformer |
| CN107526001A (en) * | 2017-09-07 | 2017-12-29 | 广东电网有限责任公司江门供电局 | A kind of intelligent line sequence detector and its detection method |
| CN109782213A (en) * | 2018-12-21 | 2019-05-21 | 国网山西省电力公司长治供电公司 | Fault finding system and method based on secondary circuit characteristic quantity |
-
2020
- 2020-04-29 CN CN202010356424.7A patent/CN111693904B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201373892Y (en) * | 2009-02-23 | 2009-12-30 | 凯迈(洛阳)电子有限公司 | Real-time detection circuit for preventing electricity-stealing in current method |
| CN105203905A (en) * | 2015-09-21 | 2015-12-30 | 国家电网公司 | Electric energy measuring secondary circuit rapid line inspection instrument |
| CN106443304A (en) * | 2016-11-07 | 2017-02-22 | 北京博纳电气股份有限公司 | Method for detecting secondary side loop state of once metering CT on ammeter exterior and detection device |
| CN206583984U (en) * | 2017-01-26 | 2017-10-24 | 国家电网公司 | A kind of anti-electricity-theft device based on transformer |
| CN107526001A (en) * | 2017-09-07 | 2017-12-29 | 广东电网有限责任公司江门供电局 | A kind of intelligent line sequence detector and its detection method |
| CN109782213A (en) * | 2018-12-21 | 2019-05-21 | 国网山西省电力公司长治供电公司 | Fault finding system and method based on secondary circuit characteristic quantity |
Non-Patent Citations (2)
| Title |
|---|
| On-line analysis of suspicious electricity stealing based on level-change detection;Yang Haitao 等;《2019 IEEE 3rd International Electrical and Energy Conference》;20200427;第90-94页 * |
| 基于异频法的分流窃电监测方法和装置;姜春阳 等;《电子科技》;20171231;第30卷(第3期);第185-188页 * |
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