CN206132853U - Aerogenerator ground net on -line monitoring early warning device - Google Patents
Aerogenerator ground net on -line monitoring early warning device Download PDFInfo
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- CN206132853U CN206132853U CN201621103279.7U CN201621103279U CN206132853U CN 206132853 U CN206132853 U CN 206132853U CN 201621103279 U CN201621103279 U CN 201621103279U CN 206132853 U CN206132853 U CN 206132853U
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- 238000012544 monitoring process Methods 0.000 title claims abstract description 34
- 239000002689 soil Substances 0.000 claims abstract description 46
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- 239000004973 liquid crystal related substance Substances 0.000 claims description 8
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Abstract
The utility model discloses an aerogenerator ground net on -line monitoring early warning device, it includes main control unit, frequency conversion constant current source, switching circuit, communication module, peripheral hardware part and soil temperature and humidity sensor, communication module, peripheral hardware part and soil temperature and humidity sensor link to each other with main control unit respectively, the frequency conversion constant current source passes through serial ports and main control unit communication, just the frequency conversion constant current source includes true RMS calculating unit, current transformer, voltage transformer, permanent flow regulator and sinusoidal wave synthesizer, the switching circuit includes four at least hilted broadsword multi -throw switch and eight at least branch road interfaces. The utility model discloses monitor ground resistance, soil resistivity, soil temperature and humidity, through setting for the warning threshold value, judge by monitoring earth mat operating condition. The utility model discloses simple structure, can remote real -time monitoring.
Description
Technical Field
The utility model relates to a aerogenerator ground net monitoring technology field specifically is an aerogenerator ground net on-line monitoring early warning device.
Background
In a grounding system of a wind driven generator, not only the grounding resistance of a fan needs to be known in time, but also the influence of the soil environment on a grounding grid needs to be considered, so that the influence of the soil resistivity, the soil temperature and humidity and the like on the grounding resistance is evaluated in addition to the testing of the grounding resistance of the fan.
In the existing solution, soil sensors are mostly adopted for direct measurement, the measurement means is single, the transmission and the processing of measurement result data are simple, the efficiency is low, the effect is not good, and the whole test process cannot be intelligently managed. In the existing grounding test system, most of the grounding test systems are tested from a single aspect, such as the simple test of grounding resistance or the simple test of soil resistivity, but the comprehensive test of factors influencing grounding is not carried out.
The publication number is: the utility model of CN204256047U discloses a novel composite function soil resistivity tester, which comprises a functional circuit module, wherein the functional circuit module comprises a soil resistivity testing part, a GPS part, a clock part and a data storage part, and the soil resistivity testing part comprises a DC/AC conversion functional module, an alternating current amplification functional module, a filtering functional module, an analog acquisition module and a reference value sampling module which are sequentially connected between a power supply and a microprocessor; the GPS part comprises a GPS position positioning module and a GPS power supply management module; the clock part comprises a clock recording module and a clock standby battery power supply module. The utility model discloses a with GPS (location), clock (time recording) function and soil resistivity tester ingenious integrated as an organic whole for monitoring and record to the soil resistivity of same place and region are more convenient and swift, also do not have the possibility that the people made mistakes of record. However, this utility model uses the GPS location to carry out the position determination of soil monitoring point, prevents to record the technical scheme who makes mistakes, and the design is complicated, does not carry out teletransmission to the backstage with data to extract more information from the post processing.
The publication number is: the utility model of CN202974924U discloses an on-line monitoring system for soil resistivity, which comprises an industrial computer, a resistivity acquisition module, an environmental data measurement module, a data transmission module and a remote control computer; the resistivity acquisition module comprises a square wave signal source, a multi-channel selection switch and an electrode which are sequentially connected; the square wave signal source, the multi-channel selection switch and the environmental data measuring module are respectively connected with the industrial computer; the data transmission module is respectively connected with the industrial computer and the remote control computer. The utility model discloses a be used for the real-time on-line monitoring of the seasonal variation law along with the soil resistivity numerical value of power system transformer substation or transmission line position, its integrated level is high, and degree of automation is high, and the configuration is nimble, and the system reliability is high, has realized synchronous acquisition and the teletransmission of multiclass data, and the practicality is strong. The utility model discloses a realized long-range on-line monitoring, can monitor soil resistivity for a long time, but owing to adopted industrial computer, increased design cost.
The publication number is: the utility model discloses a CN 202693684U's utility model discloses a ground resistance monitoring system, concretely relates to multilayer soil resistivity monitoring system, surveyed telluric electricity field including data processing center, an at least monitor, a current earthing pole, a voltage earthing pole and two at least, the point that needs the monitoring is installed under soil to surveyed telluric electricity field, data processing center is connected with the monitor, the monitor is connected with current earthing pole, voltage earthing pole and surveyed telluric electricity field respectively, the built-in accumulator of monitor. The utility model discloses a function is: the manual instant measurement and unmanned automatic timing measurement of the resistivity of the multi-layer soil at the same site are realized; long-term wired networking monitoring or wireless networking monitoring of distributed multi-site multi-layer soil resistivity based on a data center is realized; the monitoring data transmission, distribution, storage, display, query, statistics, analysis, printing and other operations are realized. The utility model discloses an integrated manual measurement and automatic measure, but its data transmission mode is single, lacks the early warning to unreasonable data and handles.
In the solution of the grounding grid monitoring system of the wind driven generator, the existing monitoring device has the disadvantages of complex design, single data transmission, low intelligence degree and higher cost, and can not perform complete systematic test on factors affecting grounding and the like.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to overcome prior art not enough, provide a aerogenerator ground net on-line monitoring early warning device to reach the long-term fixed point at least and to the monitoring of ground resistance, soil resistivity, soil humiture and with the effect at data remote transmission to backstage terminal.
The purpose of the utility model is realized through the following technical scheme: an on-line monitoring and early warning device for a grounding grid of a wind driven generator comprises a main controller, a variable-frequency constant current source, a switching circuit, a soil temperature and humidity sensor, a communication module and external components; the input and output ends of the communication module and the input and output ends of the peripheral components are respectively connected with the input and output ends of the main controller; the input and output ends of the soil temperature and humidity sensor are connected with the input and output end of the main controller; the variable-frequency constant current source is communicated with the main controller through a serial port; the switching circuit comprises at least four single-pole multi-throw switches and at least eight branch interfaces;
the variable-frequency constant current source comprises a true effective value calculating unit, a current transformer, a voltage transformer, a constant current regulator, an E pole interface, an ES pole interface, a P pole interface, a C pole interface and a sine wave synthesizer; the current signal output end of the current transformer is connected with the current input end of the true effective value calculating unit; the voltage signal output end of the voltage transformer is connected with the voltage input end of the true effective value calculating unit; the input and output ends of the adjusting signal of the true effective value calculating unit are connected with the input and output ends of the adjusting signal of the constant current adjuster; the control signal output end of the constant current regulator is connected with the control signal input end of the sine wave synthesizer;
the variable-frequency constant-current source is connected with the movable end of the first single-pole multi-throw switch through an E pole interface, connected with the movable end of the second single-pole multi-throw switch through an ES pole interface, connected with the movable end of the third single-pole multi-throw switch through a P pole interface and connected with the movable end of the fourth single-pole multi-throw switch through a C pole interface; the at least eight branch interfaces comprise an E1 pole interface, an ES1 pole interface, a P1 pole interface, a C1 pole interface, an E2 pole interface, an ES2 pole interface, a P2 pole interface and a C2 pole interface;
two of the immobile ends of the first single-pole multi-throw switch are respectively connected with an E1 pole interface and an E2 pole interface, two of the immobile ends of the second single-pole multi-throw switch are respectively connected with an ES1 pole interface and an ES2 pole interface, two of the immobile ends of the third single-pole multi-throw switch are respectively connected with a P1 pole interface and a P2 pole interface, two of the immobile ends of the fourth single-pole multi-throw switch are respectively connected with a C1 pole interface and a C2 pole interface, the other ends of the E1 pole interface, the ES1 pole interface, the P1 pole interface, the C1 pole interface, the P2 pole interface and the C2 pole interface are connected with a tested ground network, and the other ends of the E2 pole interface and the ES2 pole interface are respectively connected with a grounding body.
The communication module is an optical fiber module, and an interface of the optical fiber module is connected with a communication interface of the main controller.
The soil temperature and humidity sensor is a fully-encapsulated soil temperature and humidity sensor; the fully-encapsulated soil temperature and humidity sensor is communicated with the main controller in an RS485 bus communication mode.
The peripheral components comprise an information memory, an operation keyboard, a liquid crystal module and a real-time clock; and the input and output ends of the information memory, the operation keyboard, the liquid crystal module and the real-time clock are respectively connected with the input and output end of the main controller.
The serial port is a UART serial port or an SPI interface.
The single-pole multi-throw switch is a single-pole double-throw switch.
The utility model has the advantages that: the utility model is suitable for a long-term fixed point is to the monitoring of ground resistance, soil resistivity, soil humiture. Different sampling intervals can be set according to different requirements of users, sampled data are transmitted to a client through an optical fiber network, multi-machine centralized monitoring can be achieved, and meanwhile, an alarm threshold value can be set by a monitor to prompt the users whether a monitored ground network is in a reasonable range or not. The utility model discloses still have the characteristics that the design is simple, efficiency of software testing is high.
Drawings
Fig. 1 is a block diagram of the present invention.
Detailed Description
The technical solution of the present invention is described in further detail below with reference to the accompanying drawings, but the scope of the present invention is not limited to the following description.
An on-line monitoring and early warning device for a grounding grid of a wind driven generator comprises a main controller, a variable-frequency constant current source, a switching circuit, a soil temperature and humidity sensor, a communication module and external components; the input and output ends of the communication module and the input and output ends of the peripheral components are respectively connected with the input and output ends of the main controller; the input and output ends of the soil temperature and humidity sensor are connected with the input and output end of the main controller; the variable-frequency constant current source is communicated with the main controller through a serial port; the switching circuit comprises at least four single-pole multi-throw switches and at least eight branch interfaces;
the variable-frequency constant current source comprises a true effective value calculating unit, a current transformer, a voltage transformer, a constant current regulator, an E pole interface, an ES pole interface, a P pole interface, a C pole interface and a sine wave synthesizer; the current signal output end of the current transformer is connected with the current input end of the true effective value calculating unit; the voltage signal output end of the voltage transformer is connected with the voltage input end of the true effective value calculating unit; the input and output ends of the adjusting signal of the true effective value calculating unit are connected with the input and output ends of the adjusting signal of the constant current adjuster; the control signal output end of the constant current regulator is connected with the control signal input end of the sine wave synthesizer;
the variable-frequency constant-current source is connected with the movable end of the first single-pole multi-throw switch through an E pole interface, connected with the movable end of the second single-pole multi-throw switch through an ES pole interface, connected with the movable end of the third single-pole multi-throw switch through a P pole interface and connected with the movable end of the fourth single-pole multi-throw switch through a C pole interface; the at least eight branch interfaces comprise an E1 pole interface, an ES1 pole interface, a P1 pole interface, a C1 pole interface, an E2 pole interface, an ES2 pole interface, a P2 pole interface and a C2 pole interface;
two of the immobile ends of the first single-pole multi-throw switch are respectively connected with an E1 pole interface and an E2 pole interface, two of the immobile ends of the second single-pole multi-throw switch are respectively connected with an ES1 pole interface and an ES2 pole interface, two of the immobile ends of the third single-pole multi-throw switch are respectively connected with a P1 pole interface and a P2 pole interface, two of the immobile ends of the fourth single-pole multi-throw switch are respectively connected with a C1 pole interface and a C2 pole interface, the other ends of the E1 pole interface, the ES1 pole interface, the P1 pole interface, the C1 pole interface, the P2 pole interface and the C2 pole interface are connected with a tested ground network, and the other ends of the E2 pole interface and the ES2 pole interface are respectively connected with a grounding body.
The communication module is an optical fiber module, and an interface of the optical fiber module is connected with a communication interface of the main controller.
The soil temperature and humidity sensor is a fully-encapsulated soil temperature and humidity sensor; the fully-encapsulated soil temperature and humidity sensor is communicated with the main controller in an RS485 bus communication mode.
The peripheral components comprise an information memory, an operation keyboard, a liquid crystal module and a real-time clock; and the input and output ends of the information memory, the operation keyboard, the liquid crystal module and the real-time clock are respectively connected with the input and output end of the main controller.
The serial port is a UART serial port or an SPI interface.
The single-pole multi-throw switch is a single-pole double-throw switch.
As shown in fig. 1, the main controller is usually a Micro Control Unit (MCU) chip, and includes a CPU, a RAM, a ROM, a timing counter, various I/O interfaces, and various driving peripheral interfaces. The main controller is used as a core to distribute and schedule other parts to work in order. Because of its powerful function, it usually plays the role of "brain", responsible for data communication with external devices, interaction of man-machine devices (here, keys and incoming LCD liquid crystal modules), and commanding the effective measurement of variable frequency constant current source. The frequency conversion constant current source is used as a complete module and is communicated with the main controller through a UART serial port or an SPI interface to receive commands or return test data.
The process of measuring the grounding resistance is as follows: after the variable-frequency constant current source receives an instruction of the main controller through a serial port, the sine wave synthesizer generates a sine wave which flows out from a pole C and returns to a pole E through a tested earth network to form a current loop, at the moment, the current passes through the first current transformer and then sends a signal to a true effective value (RMS) calculation unit to calculate the magnitude of current injected into the earth network, and if the current deviates from a set value, the first constant current regulator is driven to achieve the purpose of constant current. Meanwhile, the ES pole and the P pole are sampled to a certain voltage in a current loop through a voltage transformer, the voltage is also subjected to true effective value (RMS) calculation to calculate a true voltage, and finally, the resistance value of the grounding resistor is calculated according to ohm's law.
The information storage will be used to store critical information set by the customer, such as alarm threshold values, sampling time intervals, etc., while also providing additional storage media for the system. The operation keyboard and the liquid crystal module are essential parts for man-machine interaction. The real-time clock provides important information such as year, month, day, Beijing time and the like for monitoring, and interval sampling must depend on the important information.
After the online monitoring and early warning device samples data, the data is uploaded to a server end through a communication module, and the server stores and processes the data; the client (PC) calls, queries and counts the data received by the server through the network port. In such a way, the client (PC) can realize data query, statistics and remote real-time monitoring of a plurality of grounding resistors.
The full encapsulation soil temperature and humidity sensor can work in the buried soil for a long time, and a 485 bus mode is adopted due to the fact that the test environment is changeable and the distance between a host and the sensor is not fixed. The 485 bus samples the differential mode transmission signal, and this mode interference killing feature is strong, and communication distance is far away, satisfies the system requirement.
And the grounding resistance test of the grounding body is realized through the switching circuit. And then, reversely deducing the soil resistivity through a grounding resistance calculation formula of the grounding body.
The inverse soil resistivity formula is:
wherein,
rho-soil resistivity, in Ω · m;
L1-the length of the grounding body, in m;
Rd-the grounding body power frequency grounding resistance is in units of Ω;
d is the diameter of the grounding body (or the equivalent edge width of the angle steel) and the unit m.
The foregoing has described the general principles and features of the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (6)
1. The utility model provides a aerogenerator ground net on-line monitoring early warning device which characterized in that: the device comprises a main controller, a variable-frequency constant current source, a switching circuit, a soil temperature and humidity sensor, a communication module and peripheral components; the input and output ends of the communication module and the input and output ends of the peripheral components are respectively connected with the input and output ends of the main controller; the input and output ends of the soil temperature and humidity sensor are connected with the input and output end of the main controller; the variable-frequency constant current source is communicated with the main controller through a serial port; the switching circuit comprises at least four single-pole multi-throw switches and at least eight branch interfaces;
the variable-frequency constant current source comprises a true effective value calculating unit, a current transformer, a voltage transformer, a constant current regulator, an E pole interface, an ES pole interface, a P pole interface, a C pole interface and a sine wave synthesizer; the current signal output end of the current transformer is connected with the current input end of the true effective value calculating unit; the voltage signal output end of the voltage transformer is connected with the voltage input end of the true effective value calculating unit; the input and output ends of the adjusting signal of the true effective value calculating unit are connected with the input and output ends of the adjusting signal of the constant current adjuster; the control signal output end of the constant current regulator is connected with the control signal input end of the sine wave synthesizer;
the variable-frequency constant-current source is connected with the movable end of the first single-pole multi-throw switch through an E pole interface, connected with the movable end of the second single-pole multi-throw switch through an ES pole interface, connected with the movable end of the third single-pole multi-throw switch through a P pole interface and connected with the movable end of the fourth single-pole multi-throw switch through a C pole interface; the at least eight branch interfaces comprise an E1 pole interface, an ES1 pole interface, a P1 pole interface, a C1 pole interface, an E2 pole interface, an ES2 pole interface, a P2 pole interface and a C2 pole interface;
two of the immobile ends of the first single-pole multi-throw switch are respectively connected with an E1 pole interface and an E2 pole interface, two of the immobile ends of the second single-pole multi-throw switch are respectively connected with an ES1 pole interface and an ES2 pole interface, two of the immobile ends of the third single-pole multi-throw switch are respectively connected with a P1 pole interface and a P2 pole interface, two of the immobile ends of the fourth single-pole multi-throw switch are respectively connected with a C1 pole interface and a C2 pole interface, the other ends of the E1 pole interface, the ES1 pole interface, the P1 pole interface, the C1 pole interface, the P2 pole interface and the C2 pole interface are connected with a tested ground network, and the other ends of the E2 pole interface and the ES2 pole interface are respectively connected with a grounding body.
2. The wind driven generator grounding grid online monitoring and early warning device as claimed in claim 1, wherein: the communication module is an optical fiber module, and an interface of the optical fiber module is connected with a communication interface of the main controller.
3. The wind driven generator grounding grid online monitoring and early warning device as claimed in claim 1, wherein: the soil temperature and humidity sensor is a fully-encapsulated soil temperature and humidity sensor; the fully-encapsulated soil temperature and humidity sensor is communicated with the main controller in an RS485 bus communication mode.
4. The wind driven generator grounding grid online monitoring and early warning device as claimed in claim 1, wherein: the peripheral components comprise an information memory, an operation keyboard, a liquid crystal module and a real-time clock; and the input and output ends of the information memory, the operation keyboard, the liquid crystal module and the real-time clock are respectively connected with the input and output end of the main controller.
5. The wind driven generator grounding grid online monitoring and early warning device as claimed in claim 1, wherein: the serial port is a UART serial port or an SPI interface.
6. The wind driven generator grounding grid online monitoring and early warning device as claimed in claim 1, wherein: the single-pole multi-throw switch is a single-pole double-throw switch.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621103279.7U CN206132853U (en) | 2016-10-08 | 2016-10-08 | Aerogenerator ground net on -line monitoring early warning device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201621103279.7U CN206132853U (en) | 2016-10-08 | 2016-10-08 | Aerogenerator ground net on -line monitoring early warning device |
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| CN201621103279.7U Expired - Fee Related CN206132853U (en) | 2016-10-08 | 2016-10-08 | Aerogenerator ground net on -line monitoring early warning device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107831369A (en) * | 2017-12-19 | 2018-03-23 | 成都信息工程大学 | A kind of grounding resistance monitor instrument with self-test and correction |
| CN110749777A (en) * | 2019-12-02 | 2020-02-04 | 广西地凯科技有限公司 | Soil resistivity measuring method |
-
2016
- 2016-10-08 CN CN201621103279.7U patent/CN206132853U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107831369A (en) * | 2017-12-19 | 2018-03-23 | 成都信息工程大学 | A kind of grounding resistance monitor instrument with self-test and correction |
| CN107831369B (en) * | 2017-12-19 | 2020-07-03 | 成都信息工程大学 | A grounding resistance monitor with self-test and calibration |
| CN110749777A (en) * | 2019-12-02 | 2020-02-04 | 广西地凯科技有限公司 | Soil resistivity measuring method |
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