CN113037331B - Carrier information enhancement method used between interactive devices in power distribution network - Google Patents
Carrier information enhancement method used between interactive devices in power distribution network Download PDFInfo
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- CN113037331B CN113037331B CN202110254141.6A CN202110254141A CN113037331B CN 113037331 B CN113037331 B CN 113037331B CN 202110254141 A CN202110254141 A CN 202110254141A CN 113037331 B CN113037331 B CN 113037331B
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B3/00—Line transmission systems
- H04B3/54—Systems for transmission via power distribution lines
- H04B3/544—Setting up communications; Call and signalling arrangements
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B3/00—Line transmission systems
- H04B3/54—Systems for transmission via power distribution lines
- H04B3/58—Repeater circuits
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L69/00—Network arrangements, protocols or services independent of the application payload and not provided for in the other groups of this subclass
- H04L69/22—Parsing or analysis of headers
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Abstract
The invention relates to the technical field of power distribution network communication, and aims to provide a carrier information enhancement method used among interactive devices in a power distribution network.
Description
Technical Field
The invention relates to the technical field of power distribution network communication, in particular to a carrier information enhancement method used among interactive devices in a power distribution network.
Background
In the transmission of a lot of data information from Power distribution to consumer Power consumption, a High speed Power Line Carrier Communication (HPLC) method is adopted. The cable has been widely used for power data communication due to its advantages of convenient construction, low price, etc.
High-speed power carrier communication networks still have some drawbacks in practical use. For example, the distribution transformer has a blocking effect on the power carrier signal, so that the power carrier signal can be transmitted only in the area range of one distribution transformer, and the cross-station building communication network cannot be realized. Because the principle that the signal needs impedance match when transmitting on the wire, and the distribution branch box uses very extensively at the distribution side, and signal transmission impedance is obvious in these position difference changes, and the signal impedance mismatch when transmitting solves impedance mismatch and mainly has two kinds of modes: one is to adjust the self-impedance of the signal transmission line. The second is to adjust the wavelength of the transmission signal, that is, to change the carrier frequency of the transmission signal, which is also a commonly used method at present. However, the high-speed power carrier communication network has a longer communication distance in an environment with fewer power branch nodes, and may not be able to be networked or have unstable networking in a case with more power branch nodes or more power branch levels. The existing carrier relay only adds a signal repeater on a power transmission line, theoretically plays a role in amplifying an attenuation signal, has larger impedance change in the environment with more power branch boxes, and cannot effectively meet the requirement of signal remote transmission. And the function of networking across the distribution areas cannot be realized, so that at least one power carrier host is needed for one distribution area, and the cost is wasted.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a carrier information enhancement method used among interactive devices in a power distribution network.
The method is realized by the following technical scheme: a carrier information enhancement method for interactive devices in a power distribution network is provided, wherein carrier communication among the devices in the power distribution network often passes through a plurality of branch structures, wherein the multi-stage branch structure comprises a transformer, a power distribution cabinet, a ring main unit and a power branch box,
the output end of the transformer is connected with a power distribution cabinet, the power distribution cabinet is connected with a power branch box through a ring main unit, the power is transmitted to a user through the power branch box,
the multi-stage branch structure is provided with power carrier output interfaces for connecting four groups of signals of A phase, B phase, C phase and N phase, each group of signals comprises multi-path high-speed carrier signals, two ends of the power branch box are also provided with carrier expanders in parallel, a single-branch signal is expanded into multi-branch signals through the carrier expanders for output, the carrier expanders comprise a main controller, the input end of the carrier expander is defined as a main loop power circuit, the output end of the carrier expander is defined as a branch power circuit,
the main loop C phase and the N phase are connected with a main control through a power line isolation and signal coupling circuit of the main loop, the main controller is connected with the C phase and the N phase of the branch power line through a power line isolation and signal coupling circuit of the branch power line, a carrier expander is arranged between the transformers, and signals between the two transformers are sequentially connected through the carrier expander. Preferably, when the transformers between the transformer areas 1 and 2 are in signal connection, the method for controlling the carrier expanders between the transformers includes the following steps:
step 1: when the main controller is in an interruption or polling state, detecting and receiving a carrier signal sent by a concentrator on the station area 1, recording a specific signal type of a received communication message from the station area 1, judging the specific signal type, when the signal type is a broadcast signal, executing the step 2, when the signal type is not the broadcast signal, analyzing whether a header ID number of the carrier communication message exists in the database 1, if so, executing the step 3, if not, analyzing the carrier communication message, judging whether the header ID number exists in the database 2, if so, executing the step 4, if not, forwarding the received carrier signal to the station area 2 when A, B and C are the same, when the main controller is in the interruption or polling state, detecting whether response messages exist on all phases on the station area 2, if not, executing the step 5, if so, analyzing the message ID number and establishing the database 2 corresponding to equipment ID and phase on the station area 2, and continuing to execute the step 5;
step 2: releasing the record of the phase of the communication message received from the platform area 1, and forwarding the carrier signal to the platform area 2 when A, B and C are the same;
and 3, step 3: releasing the record of the phase of the communication message received from the platform area 1;
and 4, step 4: only forwarding the received carrier signal to the corresponding phase of the database ID number on the platform area 2, enabling the main controller to be in an interrupt triggering or polling state, only detecting the corresponding phase on the platform area 2, acquiring a response message, and executing the step 6;
and 5: establishing and recording a database 1 of which the equipment ID number is not in the station area 2;
and 6: the carrier signal responded by the device on station area 2 is transmitted to the phase recorded on station area 1.
Preferably, the method for controlling the carrier wave expander on the power branch box is the same as the method for controlling the carrier wave expander between the transformers, but the input end of the carrier wave expander on the power branch box is a main loop power line, but the output end of the carrier wave expander on the power branch box is a plurality of branch power lines.
Preferably, the power carrier signals on the plurality of branch power lines are the same.
In another aspect, a computer-readable storage medium is also provided, on which one or more computer programs are stored, which when executed by one or more processors implement the carrier information enhancement method as described above.
In another aspect, an apparatus for carrier information enhancement is also provided, including: one or more processors;
a computer readable storage medium storing one or more computer programs; the one or more computer programs, when executed by the one or more processors, implement the carrier information enhancement method as described above.
In another aspect, a system for enhancing carrier information between a power distribution network and a user is provided, including: the carrier expander, the transformer and the power branch box; wherein the content of the first and second substances,
the two ends of the power branch box are also provided with carrier expanders in parallel, a single-branch signal is expanded into a multi-branch signal through the carrier expanders for output, and the carrier expanders comprise a main controller;
the main controller has stored therein one or more computer programs which, when executed by one or more processors it has, implement the carrier information enhancement method as described above.
The invention has the beneficial effects that:
(1) Carrier expanders are arranged at two ends of the branch nodes to achieve the optimization effect of the key loss position of the signal, so that the signal reaches a post-stage branch line in an optimized mode;
(2) The device is arranged at the position of a branch node encountered by high-speed power carrier communication during signal transmission, so that the influence of the obvious position of impedance occurrence on the high-speed carrier communication is greatly reduced.
Drawings
Fig. 1 is a block diagram of a general architecture of a power branch on a power distribution side according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of the operation of a master controller in an embodiment of the present invention;
FIG. 3 is a schematic diagram of the operation of a carrier expander in an embodiment of the present invention;
FIG. 4 is a data communication diagram across a power branch box of the present invention;
fig. 5 is a diagram of data communication between different stations according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention are clearly and completely described below with reference to fig. 1 to 5 of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other implementations that can be derived by one of ordinary skill in the art based on the embodiments of the present invention without making creative efforts.
In the description of the present invention, it is to be understood that the terms "counterclockwise", "clockwise", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on those shown in the drawings, and are used for convenience of description only, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be considered as limiting.
Example 1:
referring to fig. 1 of the drawings,
the carrier communication among the devices in the distribution network often passes through a plurality of branch structures, wherein the multi-stage branch structure comprises a transformer, a distribution cabinet, a ring main unit and a power branch box,
the output end of the transformer is connected with a power distribution cabinet, the power distribution cabinet is connected with a power branch box through a ring main unit, the power is transmitted to a user through the power branch box,
the multi-stage branch structure is provided with power carrier output interfaces for connecting four groups of signals of A phase, B phase, C phase and N phase, each group of signals comprises multi-path high-speed carrier signals, two ends of the power branch box are also provided with carrier expanders in parallel, a single-branch signal is expanded into multi-branch signals through the carrier expanders for output, the carrier expanders comprise a main controller, the input end of the carrier expander is defined as a main loop power circuit, the output end of the carrier expander is defined as a branch power circuit,
referring to fig. 2, phase C and phase N of the main circuit are connected to the main controller through the power line isolation and signal coupling circuit of the main circuit, the main controller is connected to phase C and phase N of the branch power line through the power line isolation and signal coupling circuit of the branch power line,
a carrier expander is arranged between the transformers, signals between the two transformers are sequentially connected through the carrier expander, and when the transformers between the transformer areas 1 and 2 are in signal connection, please refer to fig. 3, the control method of the carrier expander between the transformers comprises the following steps:
step 1: when the main controller is in an interruption or polling state, detecting and receiving a carrier signal sent by a concentrator on the station area 1, recording a specific signal type of a received communication message from the station area 1, judging the specific signal type, when the signal type is a broadcast signal, executing the step 2, when the signal type is not the broadcast signal, analyzing whether a header ID number of the carrier communication message exists in the database 1, if so, executing the step 3, if not, analyzing the carrier communication message, judging whether the header ID number exists in the database 2, if so, executing the step 4, if not, forwarding the received carrier signal to the station area 2 when A, B and C are the same, when the main controller is in the interruption or polling state, detecting whether response messages exist on all phases on the station area 2, if not, executing the step 5, if so, analyzing the message ID number and establishing the database 2 corresponding to equipment ID and phase on the station area 2, and continuing to execute the step 5;
step 2: releasing the record of the phase of the communication message received from the platform area 1, and forwarding the carrier signal to the platform area 2 when A, B and C are the same;
and step 3: releasing the record of the phase of the communication message received from the platform area 1;
and 4, step 4: only forwarding the received carrier signal to the corresponding phase of the database ID number on the platform area 2, enabling the main controller to be in an interrupt triggering or polling state, only detecting the corresponding phase on the platform area 2, acquiring a response message, and executing the step 6;
and 5: establishing and recording a database 1 of which the equipment ID number is not in the station area 2;
step 6: the carrier signal responded by the device on station area 2 is transmitted to the phase recorded on station area 1.
It should be noted that the method for controlling the carrier wave expander on the power branch box is the same as the method for controlling the carrier wave expander between the transformers, except that in the above steps 1 to 6, the single output is changed to multiple outputs, that is, the input end of the carrier wave expander on the power branch box is one main loop power line, but the output end of the carrier wave expander on the power branch box is a plurality of branch power lines.
It should be noted that the power carrier signals on the plurality of branch power lines are the same.
It should be noted that, referring to fig. 1, the power consumption of the power distribution side generally passes through a multi-stage branch structure from the transformer to the user side, the multi-stage branch structure is a power distribution cabinet, a ring main unit, and a power branch box, the power line generally branches from one input to multiple outputs in the branch structure, and the nodes are generally connected by welding, screwing, and the like. The signal transmission impedance may vary significantly at these locations. The invention discloses a method for optimizing the critical loss position of a signal by installing carrier expanders at two ends of branch nodes as shown in figure 2, so that the signal reaches a post-stage branch line in an optimized way.
It should be noted that, referring to fig. 4 and 5, the carrier expander includes a high-speed power carrier signal input interface and a power carrier signal output interface. The power carrier signal input interface generally comprises four groups of signal lines, namely, an A phase signal, a B phase signal, a C phase signal and an N phase signal, which are connected to a power line and used for detecting a high-speed power carrier signal sent by a concentrator in the power line, and when the data concentrator calls an ammeter or other equipment in the power line for data communication or communication, the carrier expander detects the signal in the power line. The power carrier output interface generally comprises four groups of signals of an A phase, a B phase, a C phase and an N phase, but each group of signals respectively comprises a plurality of high-speed carrier signal lines which are used for connecting a plurality of power branch lines of the same phase and are used for sending or receiving high-speed carrier signals of a backward stage.
The carrier expander can also build a link for high-speed carrier communication by forwarding a high-speed carrier signal, and electric meters and other equipment in the transformer area and the transformer area 2 can share equipment in the transformer area 1.
The network comprehensive safety evaluation device of the invention comprises: a processor and a computer-readable storage medium storing a computer program which, when executed by the processor, implements a network integrated security assessment method capable of the present invention. Because the program logic of each step is different, a special processor or a general-purpose chip can be adopted to execute the corresponding step, so that the processing efficiency of the whole program is improved, and the cost is reasonably controlled. Therefore, those skilled in the art can adaptively design and adjust the number of processors and computer programs in the apparatus for carrier information enhancement according to the specific application.
In summary, because the principle that conducting wire impedance matching is required for long-distance stable and efficient transmission of signals on conducting wires is adopted, various branch line devices on a power communication line are widely used on the power distribution side, the difference of signal transmission impedance at the positions is obvious in change, the impedance of signals is not matched during transmission, and two main ways for solving the impedance mismatch are provided: one is to adjust the self-impedance of the signal transmission line. Secondly, adjusting the wavelength of the transmission signal, that is, changing the carrier frequency of the transmission signal, which is also a commonly used method at present in high-speed power carrier communication,
the device is installed at the position of a branch node when high-speed power carrier communication meets signal transmission from the perspective of adjusting the impedance of a high-speed signal on a transmission line, so that the influence of an obvious position of impedance on the high-speed carrier communication is greatly reduced. Therefore, the invention optimizes the high-number power carrier communication network from the perspective of adjusting the impedance of the signal transmission line, increases the communication distance of the high-speed power carrier, stabilizes the high-speed power carrier communication network more,
and the problem that mutual communication cannot be realized among a plurality of transformer areas due to the isolation effect of the transformer is solved, the number of concentrators is reduced, and the cost of high-speed power line carrier communication is optimized.
Claims (5)
1. A carrier information enhancement method used between interactive devices in a power distribution network is characterized in that carrier communication is achieved between devices in the power distribution network through a multi-stage branch structure, wherein the multi-stage branch structure comprises a transformer, a power distribution cabinet, a ring main unit and a power branch box, the output end of the transformer is connected with the power distribution cabinet, the power distribution cabinet is connected with the power branch box through the ring main unit, power is sent to users through the power branch box, power carrier output interfaces are arranged on the multi-stage branch structure and used for connecting four groups of signals of A phase, B phase, C phase and N phase, each group of signals comprises multi-path high-speed carrier signals, carrier expanders are further arranged at two ends of the power branch box in parallel, the single-path signals are expanded into multi-path signals to be output through the carrier expanders, the carrier expanders comprise a main controller, the input end of each carrier expander is defined as a main loop power line, the output end of each carrier expander is a branch power line, the C phase and the N phase of the main loop are connected with an isolation power line and a signal coupling circuit of the main controller, the C phase and the signal expander are connected with the main controller through a power line isolation and a signal coupling circuit, the C phase and the transformer, and the carrier expanders are sequentially connected with the two carrier signal expansion circuits of the two carrier;
when the transformers between the transformer areas 1 and 2 are in signal connection, the control method of the carrier expander between the transformers comprises the following steps:
step 1: when the main controller is in an interruption state or a polling state, detecting and receiving a carrier signal sent by a concentrator on the station area 1, recording a specific signal type of a received communication message from the station area 1, judging the specific signal type, when the signal type is a broadcast signal, executing a step 2, when the signal type is not the broadcast signal, analyzing whether a header ID number of the carrier communication message exists in the database 1, if so, executing a step 3, if not, analyzing the carrier communication message, judging whether the header ID number exists in the database 2, if so, executing a step 4, if not, forwarding the received carrier signal to A, B and C on the station area 2 when the header ID number is the same, if not, detecting whether response messages exist on all phases on the station area 2, if not, executing a step 5, if so, analyzing the message ID number and establishing a database 2 corresponding to equipment ID and phase on the station area 2 according to the carrier signal and phase returned on the station area 2, and continuing to execute the step 5;
and 2, step: releasing the record of the phase of the communication message received from the platform area 1, and forwarding the carrier signal to the platform area 2 when A, B and C are the same;
and 3, step 3: releasing the record of the phase of the communication message received from the platform area 1;
and 4, step 4: only forwarding the received carrier signal to the corresponding phase of the database ID number on the platform area 2, enabling the main controller to be in an interrupt triggering or polling state, only detecting the corresponding phase on the platform area 2, acquiring a response message, and executing the step 6;
and 5: establishing and recording a database 1 of which the equipment ID number is not in the station area 2;
and 6: sending a carrier signal responded by equipment in the platform area 2 to the phase recorded in the platform area 1;
the control method of the carrier expander on the power branch box is the same as that of the carrier expander between the transformers, but the input end of the carrier expander on the power branch box is a main loop power line, but the output end of the carrier expander on the power branch box is a plurality of branch power lines.
2. The method as claimed in claim 1, wherein the power carrier signals on the plurality of branch power lines are the same.
3. A computer-readable storage medium, wherein one or more computer programs are stored on the computer-readable storage medium, and wherein when executed by one or more processors, implement the carrier information enhancement method according to any one of claims 1 to 2.
4. An apparatus for carrier information enhancement, comprising: one or more processors;
a computer readable storage medium storing one or more computer programs; the one or more computer programs, when executed by the one or more processors, implement the method of carrier information enhancement as claimed in any one of claims 1 to 2.
5. A system for enhancing carrier information between a power distribution network and a user, comprising: the carrier expander, the transformer and the power branch box; the carrier expanders expand single-branch signals into multi-branch signals to be output, and each carrier expander comprises a main controller; the main controller has stored therein one or more computer programs that, when executed by one or more processors it has, implement the carrier information enhancement method of claim 1.
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| KR101587957B1 (en) * | 2014-06-02 | 2016-02-03 | 홍순용 | Power control system in power distribution panel |
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| CN205622317U (en) * | 2016-03-28 | 2016-10-05 | 安徽皖投新辉光电科技有限公司 | Multifunctional network system based on street lamp power network |
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