A method for constructing carrier communication attenuation model based on data statistics

Abstract

The present invention discloses a method for constructing a carrier communication attenuation model based on a data statistics method, and its technical solution includes: step 1, collecting low-voltage channel attenuation data from transformer to primary node, point-to-point and ultra-long distance in different periods of the pilot area; step 2, obtaining the average channel attenuation of the segment; step 3, respectively counting the segmented probability distribution of the attenuation data from transformer to primary node, point-to-point and ultra-long distance, and obtaining a data statistical model of channel attenuation. The model can truly simulate the attenuation environment on site, which helps R&D personnel to grasp the attenuation characteristics of the carrier communication channel, so as to optimize the communication algorithm in a targeted manner.

Description

Technical Field

[0001] The present invention relates to the technical field of low-voltage power line carrier communication, and in particular to a method for constructing a carrier communication attenuation model based on data statistics. Background Art

[0002] Low-voltage power line carrier communication uses power lines as the transmission medium to transmit power and information. With its wide coverage and no need for additional investment, power lines have attracted widespread attention in the fields of smart grids and remote meter reading. However, the low-voltage distribution network is an open network, and the random access and disconnection of different loads make the power line channel exhibit strong time-varying characteristics. In particular, the load diversity, impedance mismatch, various noise interference and other phenomena on the power channel make the power line channel environment very harsh. In order to further improve the efficiency of carrier communication and improve the reliability of carrier communication technology, it is very necessary to study the characteristics of low-voltage power line carrier communication channels.

[0003] As for the attenuation characteristics of the low-voltage power line carrier communication channel, the different distances and positions of the transceiver nodes in the same distribution area, and the different configurations of power equipment in different distribution areas will affect the attenuation characteristics between the transceiver nodes. In addition, the carrier communication channel is also frequency selective and time-varying. Therefore, in order to grasp the attenuation characteristics of the carrier communication channel and realize the simulation of the carrier communication channel attenuation in the software, it is necessary to establish a model for the carrier communication channel attenuation. Summary of the invention

[0004] The present invention proposes a method for constructing a carrier communication attenuation model based on data statistics, which proposes to collect carrier communication channel attenuation data from transformer to primary node, point to point and ultra-long distance in multiple time periods. And according to the collected attenuation data, a segmented carrier communication attenuation model based on data statistics is established.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A method for constructing a carrier communication attenuation model based on data statistics comprises the following steps:

[0007] Step 1: Select the pilot low-voltage power line carrier communication channel to be modeled, and use data collection equipment to collect at least 100 sets of low-voltage power line carrier communication channel attenuation from transformer to primary node, point-to-point and ultra-long distance in different time periods.

[0008] Step 2: Consider the frequency band attenuation of the high-speed carrier communication frequency of 0.781MHz~11.96MHz. Group every N frequency points of the 0.781MHz~11.96MHz frequency band as a small frequency band. Take the average of the attenuation amplitude of each small frequency band as the approximate attenuation of the small frequency band. Connect the approximate attenuation values ​​of each small frequency band to get the average channel attenuation of the segment. The value of N is in the range of 1 to 10.

[0009] Step 3: After obtaining the average channel attenuation of all segments using the method in step 2, the probability distribution of the average attenuation of each small frequency band from the transformer to the primary node, point-to-point and ultra-long distance attenuation data is statistically analyzed to obtain the segmented average channel attenuation probability distribution diagram, which is the data statistical model of low-voltage channel attenuation.

[0010] Furthermore, the primary node in step 1 is generally the first electric meter from the transformer to each branch in the power topology, located at the connection between each branch and the main line. Point-to-point attenuation collection refers to the attenuation collection between two electric meters, and attenuation collection between ultra-long distances generally refers to the attenuation collection between two points over 200 meters.

[0011] Furthermore, in step 2, since 511 subcarriers are specified in the low-voltage power line high-speed carrier communication protocol, the subcarrier spacing is 0.024414 MHz. The 0.781 MHz to 11.96 MHz frequency band is grouped into N frequency points as a small frequency band, that is, the bandwidth of each small frequency band is 0.024414·N MHz. The average channel attenuation calculation method for each 0.024414·N MHz bandwidth is:

[0012]

[0013] Where H i It represents the channel attenuation of the i-th frequency point, and N represents that the small frequency band contains N frequency points in total.

[0014] The beneficial effects of the present invention are as follows: a method for constructing a carrier communication attenuation model based on data statistics is provided, the carrier communication frequency band 0.781MHz~11.96MHz is divided into multiple small frequency bands, the average attenuation of each sub-frequency band is statistically analyzed, and a segmented carrier communication attenuation model based on data statistics is obtained. By using this model, not only can the on-site attenuation environment be truly simulated and the objective law of attenuation on the carrier communication frequency band be mastered, but also the extreme environment on site can be simulated according to simulation needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the method flow of the present invention.

[0016] Figure 2 is a set of channel attenuations in the embodiment of the present invention.

[0017] Figure 3 is a group of segmented average channel attenuations in the embodiment of the present invention.

[0018] Figure 4 This is the channel attenuation probability distribution model from the transformer to the primary node in the embodiment of the present invention.

[0019] Figure 5 This is a point-to-point channel attenuation probability distribution model in an embodiment of the present invention.

[0020] Figure 6 This is the channel attenuation probability distribution model for ultra-long distances in an embodiment of the present invention. Implementation

[0021] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not limit the present invention.

[0022] Combined with Figure 1 , a method for constructing a carrier communication attenuation model based on data statistics, comprising the following steps:

[0023] Step 1: Divide a day into 5 time periods (9:00 to 11:00, 11:00 to 13:00, 14:00 to 16:00, 17:00 to 19:00, and 19:00 to 21:00) to collect attenuation data from the transformer to the primary node, point-to-point, and ultra-long distance carrier communication channels. A total of 70 sets of attenuation data from the transformer to the primary node, 15 sets of attenuation data from the meter end to the meter end, and 15 sets of attenuation data from ultra-long distances were collected.

[0024] Step 2: Take the 0.781MHz~11.96MHz frequency band as a group of 10 frequency points as a small frequency band, that is, the bandwidth of each small frequency band is 0.24414MHz, and take the average of the attenuation amplitude of each small frequency band as the approximate attenuation within each 0.24414MHz bandwidth. Connect the approximate attenuation values ​​of each small frequency band to get the average channel attenuation of the segment. The average channel attenuation calculation method for each small frequency band is:

[0025]

[0026] In this example, H i represents the channel attenuation of the ith frequency point, and N equals 10, which means that the small frequency band contains 10 frequency points in total. Taking a set of attenuation curves as an example, the original channel attenuation is as follows: Figure 2 As shown, the segmented average channel attenuation is Figure 3 shown.

[0027] Step 3: After obtaining the average channel attenuation of all segments using the method in step 2, the segmented average attenuation probability distribution of 70 groups of transformer to primary node attenuation data, the segmented average attenuation probability distribution of 15 groups of point-to-point attenuation data, and the segmented attenuation probability distribution of 15 groups of ultra-long distance attenuation data are statistically analyzed to obtain the segmented average channel attenuation probability distribution diagrams, as shown in Figure 2. Figure 4-Figure 6 As shown in FIG. 1 , this is the data statistical model of low-voltage channel attenuation.

[0028] The above embodiments are descriptions of specific implementation methods of the present invention rather than limitations of the present invention. Technical personnel in the relevant technical field may make various changes and modifications to obtain corresponding equivalent technical solutions without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions should be included in the patent protection scope of the present invention.

Claims

1. A method for constructing a carrier communication attenuation model based on data statistics, characterized in that: The following steps are involved: Step 1: Select a pilot low-voltage power line carrier communication channel to be modeled, and use a collection device to collect attenuation data of no less than 100 groups of low-voltage power line carrier communication channels from transformer to primary node, point to point, and ultra-long distance in different time periods; Step 2: Consider the frequency band attenuation of the high-speed carrier communication frequency band of 0.781MHz~11.96MHz. Take every N frequency points of the frequency band of 0.781MHz~11.96MHz as a group as a small frequency band. The average attenuation amplitude of each small frequency band is taken as the approximate attenuation of the small frequency band. The approximate attenuation values ​​of each small frequency band are connected to obtain the average channel attenuation of the segment. The value of N is in the range of 1~10. Step 3, after obtaining the average channel attenuation of all segments using the method in step 2, the probability distribution of the average attenuation of each small frequency band from the transformer to the primary node, point-to-point and ultra-long distance attenuation data is statistically analyzed to obtain the segmented average channel attenuation probability distribution diagram, which is the data statistical model of the low-voltage power line carrier communication channel attenuation.

2. The method for constructing a carrier communication attenuation model based on data statistics according to claim 1, characterized in that: The primary node in step 1 is the first electric meter from the transformer to each branch in the power topology, located at the connection between each branch and the main line. Point-to-point attenuation collection refers to the attenuation collection between two electric meters, and attenuation collection between ultra-long distances refers to the attenuation collection between two points over 200 meters.

3. The method for constructing a carrier communication attenuation model based on data statistics according to claim 1, characterized in that: In step 2, the subcarrier spacing is 0.024414 MHz; each N frequency points in the 0.781 MHz to 11.96 MHz frequency band are grouped as a small frequency band, that is, the bandwidth of each small frequency band is 0.024414· N MHz; every 0.024414 N The average channel attenuation in MHz bandwidth is calculated as: In the formula H i Indicates i The channel attenuation of each frequency point is N, where N means that the small frequency band contains N frequency points in total.

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