CN110514903A - Ground resistance state evaluation and on-line early warning cloud monitoring system - Google Patents

Abstract

The invention proposes a grounding resistance state evaluation and online early warning cloud monitoring system, including several detection terminals, the detection terminal includes a box body, the box body is installed on the pole tower cross arm, the upper part of the box body is equipped with a solar panel, and the bottom of the box body There is an outlet hole, and a signal processing unit is installed in the box. The signal processing unit is connected to the signal acquisition unit through the signal line through the outlet hole. The signal signal processing unit is connected to the MCU, and the MCU is respectively connected to the power conversion module and the signal generation unit. , the communication module, the clock module, the positioning module and the storage module are connected, the power conversion module is connected with the solar battery and the backup battery respectively, and the signal generation unit is connected with the signal acquisition unit. The present invention monitors the grounding resistance in each area in real time without being limited by distance, and the system is conveniently networked, so that the data of multiple monitoring points can be simultaneously monitored at different locations, and once an abnormality occurs, the person in charge of the area will be notified in time for maintenance.

Description

Grounding resistance status evaluation and online early warning cloud monitoring system

technical field

The invention relates to the technical field of ground resistance detection, in particular to a ground resistance state evaluation and online early warning cloud monitoring system.

Background technique

In recent years, lightning tripping has always been the first of all kinds of faults. Lightning disaster has become an important factor affecting the safe operation of transmission lines, and after the line is struck by lightning, the intrusive wave that enters the substation along the transmission line threatens the electrical in the substation. Equipment is often the main factor causing substation accidents, especially in areas with strong lightning activities, high soil resistivity, and complex terrain, the accident rate of distribution equipment is higher, causing huge economic losses.

And the lightning accidents of the line account for a large proportion in the total lightning accidents of the power system. Moreover, after the line is struck by lightning, the intrusive wave transmitted to the substation along the transmission line threatens the electrical equipment in the substation, and is often an important factor causing substation accidents. In short, lightning accidents on transmission lines occur frequently and cause great damage to the power system. At present, the method to solve the above-mentioned problems is to install a grounding device for the transmission line. A qualified grounding device can provide a discharge channel for the lightning current, thereby effectively avoiding the lightning tripping of the transmission line. The grounding resistance value is an important index to measure whether the grounding device is qualified. In order to ensure the safe and reliable operation of the grounding device of various electrical equipment and electrical equipment, the grounding resistance value of the grounding system must be measured and checked regularly according to regulations. However, due to the large number of towers in the power transmission system, the actual measurement of the grounding resistance of the grounding system becomes a very heavy work.

Contents of the invention

In view of the large number of transmission system towers in the region, the manual measurement work is very heavy, and the technical problems that manual errors are easily introduced during manual measurement, the present invention proposes a grounding resistance status evaluation and online early warning cloud monitoring system.

In order to solve the problems referred to above, technical scheme of the present invention is realized like this:

A grounding resistance state evaluation and online early warning cloud monitoring system, including several detection terminals, the detection terminal includes a box body, the box body is installed on the cross arm of the pole tower, the upper part of the box body is equipped with a solar panel, and the bottom of the box body is equipped with an outlet hole , the box is equipped with a signal processing unit, the signal processing unit is connected to the signal acquisition unit through the signal line through the outlet hole, the signal signal processing unit is connected to the MCU, and the MCU is respectively connected to the power conversion module, signal generation unit, communication module, The clock module, the positioning module and the storage module are connected, the power conversion module is connected with the solar battery and the backup battery respectively, the signal generation unit is connected with the signal acquisition unit; the communication module is connected with the upper computer, and the upper computer is connected with the background control system Connected, the background control system is connected with the mobile terminal.

Preferably, the lower part of the box body is provided with a connecting plate, and the bottom of the connecting plate is provided with an installation groove, and the installation groove is matched with the pole tower cross arm and the pole tower cross arm is connected with the connection plate.

Preferably, the signal acquisition unit includes a current transformer and a voltage transformer, both the current transformer and the voltage transformer are connected to the signal processing unit, and the voltage transformer is connected to the signal generation unit.

Preferably, the signal processing unit includes a current-voltage conversion module II, the current-voltage conversion module II is respectively connected to the current transformer and the voltage transformer in the signal acquisition unit, the current-voltage conversion module II is connected to the filter module, and the filter module It is connected with the range switching module, the range switching module is connected with the AC/DC conversion module, the AC/DC conversion module is connected with the AD conversion module, and the AD conversion module is connected with the MCU.

Preferably, the signal generation unit includes a signal generation module, the signal generation module is connected to the MCU, the signal generation module is connected to the current-voltage conversion module I, the current-voltage conversion module I is connected to the signal amplification module, and the signal amplification module is connected to the signal The selection modules are connected, the signal selection module is connected with the power amplification module, and the power amplification module is connected with the voltage transformer.

Preferably, the communication module is a GPRS communication module.

Preferably, the voltage transformer and the current transformer are ring-shaped voltage transformers and ring-shaped current transformers respectively.

Beneficial effects of the present invention: the present invention monitors the grounding resistance in each area in real time through the current transformer and the voltage transformer, and the voltage transformer doubles as a frequency conversion voltage signal injection coil, and the positioning module in the detection terminal performs positioning and monitoring of the detection position in real time, The detection parameters are transmitted to the MCU, and the MCU transmits the detection parameters to the host computer in real time through the communication module without distance restrictions. The system networking is convenient, and the background control system receives various detection parameters to simultaneously monitor multiple monitoring points at different locations Data monitoring, once there is an abnormality, the background control system will promptly notify the responsible personnel in the area to carry out maintenance.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

FIG. 1 is a system architecture diagram of the present invention.

FIG. 2 is a schematic structural diagram of a detection terminal in the present invention.

Fig. 3 is a bottom view of Fig. 2 .

Fig. 4 is a signal principle block diagram of the present invention.

In the figure, 1 is the MCU, 2 is the signal generation module, 3 is the current-voltage conversion module I, 4 is the signal amplification module, 5 is the signal selection module, 6 is the power amplification module, 7 is the voltage transformer, 8 is the current transformer , 9 is the current and voltage conversion module II, 10 is the filter module, 11 is the range switching module, 12 is the AC-DC conversion module, 13 is the AD conversion module, 14 is the positioning module, 15 is the power conversion module, 16 is the clock module, 17 18 is a 4G module, 19 is a solar battery, 20 is a box, 21 is a solar panel, 22 is a connecting plate, 23 is an installation slot, and 24 is an outlet hole.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

As shown in Figure 1, a grounding resistance state evaluation and online early warning cloud monitoring system includes several detection terminals, the detection terminal includes a box body 20, the box body 20 is installed on the cross arm of the tower, and the lower part of the box body 20 is provided with a connecting plate 22. There is an installation groove 23 at the bottom of the connecting plate 22. The installation groove 23 is matched with the cross arm of the tower and the cross arm of the tower is connected with the connecting plate 22, that is, the box is installed on the cross arm of the tower, and the connecting plate and the cross arm are connected by bolts. Fixed connection.

As shown in Figures 2 and 3, a solar panel 21 is provided on the top of the box body 20, the solar panel 21 is connected to the solar battery 19, an outlet hole 24 is provided at the bottom of the box body 20, and a signal processing unit is arranged inside the box body 20 , the signal processing unit is connected to the signal acquisition unit through the outlet hole 24 through the signal line, the signal signal processing unit is connected to the MCU1, and the MCU1 is respectively connected to the power conversion module 15, the signal generation unit, the communication module 18, the clock module 16, and the positioning module 14 is connected with the storage module 17, and the power conversion module 15 is connected with the solar battery 19 and the backup battery respectively, and the solar battery and the backup battery are used to switch the power supply with the power conversion module, so as to avoid the situation of power failure in the detection box, and the clock module is used For timing, timing, etc., the positioning module is a GPS positioning module or a Beidou positioning module for real-time positioning of the measurement position, the storage module is used for locally storing detection data, and the signal generation unit is connected with the signal acquisition unit; the communication module 18 is connected to the upper The machine phase is connected, the communication module 18 is a GPRS communication module, and the detection parameters are transmitted to the upper computer in real time by using the communication module, so that the monitoring center can understand the grounding resistance situation of each area in real time, the upper computer is connected with the background control system, and the background control system is connected with the mobile terminal. The mobile terminal is a smart phone or a tablet computer. Once the grounding resistance value of a tower downconductor is abnormal and is not within the safe range, the background control system will send an alarm message to the responsible person in the area to hold the mobile terminal to remind the area Responsible for maintenance.

Described signal acquisition unit comprises current transformer 8 and voltage transformer 7, and current transformer 8 and voltage transformer 7 are all connected with signal processing unit, and voltage transformer 7 and current transformer 8 are ring voltage transformer and ring respectively. Current transformers, voltage transformers and current transformers are placed in the installation slot when not in use. When the voltage transformers and current transformers are used for measurement, the voltage transformers and current transformers are respectively connected to the four down conductors of the tower. Above, both the current transformer 8 and the voltage transformer 7 are connected to the signal processing unit, and the voltage transformer 7 is connected to the signal generation unit.

The signal processing unit includes a current-voltage conversion module II9. The current-voltage conversion module II9 is used to convert the signal detected by the voltage transformer or current transformer. The current-voltage conversion module II9 is connected with the current transformer 8 and the current transformer in the signal acquisition unit respectively. The voltage transformers 7 are connected, the current and voltage conversion module II9 is connected with the filter module 10, and the converted signal is filtered by the filter module, the filter module 10 is connected with the range switching module 11, and the filtered signal is switched through the range switching module Within the range of digital quantities corresponding to the MCU, the range switching module 11 is connected to the AC-DC conversion module 12, and the processed signal is converted into DC by the AC-DC conversion module, and the AC-DC conversion module 12 is connected to the AD conversion module 13 , and finally convert the DC signal into a digital signal, and the AD conversion module 13 is connected with the MCU1.

The signal generation unit includes a signal generation module 2, the signal generation module 2 is connected to the MCU1, the MCU controls the signal generation module to inject a voltage signal into the down conductor, the voltage transformer doubles as a voltage injection coil, and the signal generation module 2 is connected with the current-voltage conversion The module I3 is connected, and the signal source is converted by the current-voltage conversion module I. The current-voltage conversion module I3 is connected with the signal amplification module 4. The signal amplification module is used to amplify the converted signal. The signal amplification module 4 and the signal The selection module 5 is connected, and the signal selection module is used to provide a choice to follow the given signal to three outputs, convert one signal into another signal compared with the standard quantity or reference quantity, and be used for dividing range control, For valve sequence or output selection, the signal selection module 5 is connected to the power amplification module 6 , which is used to amplify the selected signal, and the power amplification module 6 is connected to the voltage transformer 7 .

As shown in Figure 4, when in use, the voltage transformer and current transformer are connected to the down conductor, and the voltage transformer is used as the input coil of the frequency conversion signal to inject the frequency conversion signal into the multiple down conductors, and the measured voltage and current The signal is transmitted to the MCU in real time, and the MCU stores the location information, time information and voltage and current information in the storage module, and at the same time transmits the above information to the host computer through the GPRS communication network, and the monitoring center receives the detection of various places through the host computer. Information, and then through the free line measurement of the grounding resistance of the tower, a specific matrix equation is used to calculate, and the matrix equation of voltage and current is established by measuring the voltage and current of the grounding conductor. Specifically, Zg is the grounding resistance impedance value of the tower under test, and ZL is The parallel equivalent resistance impedance of all towers on the left side, ZR is the parallel equivalent resistance impedance value of all towers on the right side, Z1 and Z2 are the equivalent resistance impedance of two lightning protection lines between the tower under test and the first base tower on the left and right sides respectively value. By solving the matrix equations, the circuit parameters can be determined. Assuming the grounding resistance of the tower is Rg, then Rg=Re(Zg), which can realize the rapid measurement of the grounding resistance of the tower, avoiding the heavy work of the tester who has to untie the redundant down-conductors, and is applicable to any number of down-conductors. The tower of the line reduces the labor intensity of the staff, and also greatly improves the measurement accuracy and measurement efficiency. Once the grounding resistance value of the down-conductor of the tower in the area is not within the safe range, the background control system sends an alarm signal to the person in charge of the area to remind the person in charge of the area to overhaul and maintain the down-conductor in the area.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of the present invention. within the scope of protection.

Claims (7)

1. A grounding resistance state evaluation and online early warning cloud monitoring system, characterized in that it includes several detection terminals, the detection terminal includes a box (20), the box (20) is installed on the cross arm of the tower, and the box (20 ) is provided with a solar panel (21) on the upper part, the solar panel (21) is connected with the solar battery (19), the bottom of the box body (20) is provided with an outlet hole (24), and the box body (20) is provided with a signal processing The signal processing unit is connected to the signal acquisition unit through the signal line through the outlet hole (24), the signal signal processing unit is connected to the MCU (1), and the MCU (1) is respectively connected to the power conversion module (15) and the signal generation unit , the communication module (18), the clock module (16), the positioning module (14) and the storage module (17) are connected, the power conversion module (15) is connected with the solar battery (19) and the backup battery respectively, and the signal generating unit is connected with the The signal acquisition unit is connected; the communication module (18) is connected with the upper computer, the upper computer is connected with the background control system, and the background control system is connected with the mobile terminal. 2. The grounding resistance state evaluation and online early warning cloud monitoring system according to claim 1, characterized in that, the lower part of the box (20) is provided with a connecting plate (22), and the bottom of the connecting plate (22) is provided with an installation groove (23), the mounting groove (23) is matched with the pole tower cross arm and the pole tower cross arm is connected with the connecting plate (22). 3. The grounding resistance state evaluation and online early warning cloud monitoring platform according to claim 1, characterized in that, the signal acquisition unit includes a current transformer (8) and a voltage transformer (7), and the current transformer (8 ) and the voltage transformer (7) are connected to the signal processing unit and the voltage transformer (7) is connected to the signal generation unit. 4. The grounding resistance state evaluation and online early warning cloud monitoring system according to claim 1 or 3, characterized in that, the signal processing unit includes a current-voltage conversion module II (9), and the current-voltage conversion module II (9) respectively It is connected with the current transformer (8) and the voltage transformer (7) in the signal acquisition unit, the current-voltage conversion module II (9) is connected with the filter module (10), the filter module (10) is connected with the range switching module (11 ), the range switching module is connected with (11) the AC/DC conversion module (12), the AC/DC conversion module (12) is connected with the AD conversion module (13), and the AD conversion module (13) is connected with the MCU (1) connect. 5. The grounding resistance state evaluation and online early warning cloud monitoring system according to claim 3, characterized in that the signal generation unit includes a signal generation module (2), and the signal generation module (2) is connected to the MCU (1) , the signal generation module (2) is connected to the current-voltage conversion module I (3), the current-voltage conversion module I (3) is connected to the signal amplification module (4), the signal amplification module (4) is connected to the signal selection module (5) The signal selection module (5) is connected with the power amplification module (6), and the power amplification module (6) is connected with the voltage transformer (7). 6. The grounding resistance state evaluation and online early warning cloud monitoring system according to claim 1, characterized in that the communication module (18) is a GPRS communication module. 7. The grounding resistance state evaluation and online early warning cloud monitoring system according to claim 1, characterized in that the voltage transformer (7) and current transformer (8) are ring voltage transformers and ring current transformers respectively .