CN105676060A - Smart grid sensing device - Google Patents
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- CN105676060A CN105676060A CN201410659731.7A CN201410659731A CN105676060A CN 105676060 A CN105676060 A CN 105676060A CN 201410659731 A CN201410659731 A CN 201410659731A CN 105676060 A CN105676060 A CN 105676060A
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Abstract
The present invention discloses a smart grid sensing device. The smart grid sensing device comprises a central processing unit, a global positioning system connected with the central processing unit, a large-volume data buffer, a temperature sensor, a high-precision analog-digital converter, an induction taking power circuit, a short-range wireless communication module and a long-range wireless communication module. The central processing unit is connected with a digital analog converter which is connected with a crystal oscillator, and the crystal oscillator is connected with the central processing unit. Through adoption of a mode of taking power from power induction current, the smart grid sensing device supplies power to a device with no need for external power source and battery; and the smart grid sensing device is not limited by single-end power supply and is slightly influenced by the factors such as the fluctuation of load, the harmonic wave, the grounding resistance, the fault close angle and the like; and moreover, the original fault transient state information and the opposite end information are effectively utilized in the fault feature extraction, the single-phase earth fault line selection and positioning problems of a small current grounding system are effectively solved.
Description
Technical field
The present invention relates to a kind of intelligent grid sensing device in below 35kV distribution network system.
Background technology
State Grid Corporation of China has pointed out the developing goal of the strong intelligent grid of all-round construction, and electric network state detection technique is improve smart grid security maintenance level and power equipment management benefit to provide strong technical support.
The big target of intelligent distribution system three: safe and reliable, high-quality and efficient, flexible interaction. In intelligent grid, the key project of distribution link includes: distribution network structure construction and transformation, power distribution automation pilot with practical, associate and the interactive application etc. accessed with control and distribution system integrating relevant information island, distribution power. In order to meet user's requirement to power supply reliability, the quality of power supply and good service, the unperturbed meeting distributed power source, concentration and distributed energy storage accesses, and in following electrical network, traditional distribution system operational mode and management method are urgently improved; Intelligent power distribution network is the foundation stone of strong intelligent grid, and strong in extra-high voltage, intelligence is at power distribution network.
There is many drawbacks in existing electrical power distribution automatization system:
(1) on-line measurement data are lacked, it is impossible to learn circuit ruuning situation in time;
(2) malfunction elimination location efficiency is extremely low, even needs artificial power failure to come trouble-shooting circuit and the position of fault;
(3) for security consideration, general only conveying, far below the power of rated line capacity, causes that existing power distribution network is greatly wasted.
And existing line selection apparatus or fault detector there is problems in that
(1) line selection apparatus method is single. Being typically limited to adopt realizing than a certain kind selection methods such as width phase comparing method, quintuple harmonics method, energy function method, wavelet method of single-end electrical quantity, success rate is extremely low;
(2) conventional failure indicator is based on local overcurrent, is only suitable for single ended power supply circuit, and battery is powered, and the life-span is short, perishable.
35kV and following power distribution network generally run by small current neutral grounding (isolated neutral or through grounding through arc) mode, and it has the advantages that when system generation singlephase earth fault, and stable fault currents is little, and system can continue to run with 2 to 3 hours.For single-phase transient earthing fault, trouble point electric arc can self-extinguish; For single-phase continuous earth, system can temporarily run a few hours by tape jam, and therefore domestic 35kV and following power distribution network mostly adopt this earthing mode. When its shortcoming is that single-phase continuous earth fault occurs, which bar line fault is difficult to detect is. Because fault can cause healthy phases voltage significantly to raise, and intermittent arc grounding is likely to cause electric arc overvoltage, threaten system equipment insulation safety, long period is run and may cause insulation breakdown that pernicious phase-to phase fault occurs, faulty line need to be determined as early as possible, fix a breakdown, otherwise have big potential safety hazard.
Summary of the invention
For the deficiencies in the prior art, it is an object of the invention to provide a kind of energy automatic route selection when small current neutral grounding system generation singlephase earth fault, and the device of quick locating bad lines can be realized.
For achieving the above object, present invention employs following technical scheme:
A kind of intelligent grid sensing device, it includes:
Central processing unit, for passing through the real-time sampling controlling high-precision adc realization to power line current, realize power voltage line collection by controlling temperature sensor and be converted into temperature data, and to the parsing of the initialization of global positioning system device, timing information and geographic coordinate information and process, and to the initialization of short range communicator and telecommunication device and communication scheduling;
Global positioning system, for loading precise time label to sampled data;
Large Volume Data buffer, for storing electric lines of force at the real time temperature set in time range, electric current and voltage data;
Temperature sensor, this sensor directly contacts with electric lines of force, for converting the temperature of the electric lines of force recorded to voltage signal;
High-precision adc, for power line current real time data sampling;
Short-distance wireless communication device, is used for the intercommunication mutually being arranged between the intelligent grid sensing device of adjacent, then by master device, the intelligent grid sensing device of adjacent is uniformly carried out data acquisition, distribution and the communication with far-end backstage;
Remote-wireless communicator, for the data communication between intelligent grid sensing device and backstage;
Digital to analog converter, for being converted to analog voltage signal by the clock jitter calculated on central processing unit from digital signal; And
Crystal oscillator, for providing high-precision work clock to central processing unit, carries out automatic frequency calibration according to the pps pulse per second signal of global positioning system output.
Further optimization as such scheme, described central processing unit is connected with global positioning system, Large Volume Data buffer, temperature sensor, high-precision adc, short-distance wireless communication device, remote-wireless communicator and digital to analog converter, described digital to analog converter connects crystal oscillator, and described crystal oscillator is connected with central processing unit.
Further, it also includes sensing power-supply circuit, in order to from power induction power taking and power to central processing unit and other devices.
Further, described central processing unit adopts 32 low power processors.
Further, described temperature sensor adopts resistance temperature detection sensor.
Further, described analog-digital converter sampling rate is 50 cycles per second, each cycle 256 sampling points of sampling.
Further, described temperature sensor detection conductor temperature ranges for-40 ~ 125 DEG C.
Further, it also includes out box screw rod, upper cover and lower cover, and described upper cover and lower cover are combined closely, described in open box screw rod and be located at lower cover bottom, and described in open top and the upper cover inner faces contact of box screw rod.
Assembly of the invention utilizes global positioning system (GPS) to realize the precise synchronization of each point sampled data, then pass through short distance and remote-wireless communication, by unified for the sampled data of each point Cloud Server sending backstage to, background server adopts transient state difference current algorithm, stable state homopolar power and manual decision's system to realize comprehensive fault line selection and fault locating.
Compared with prior art, the present invention at least has the following characteristics that
(1) mode from power induction electric current power taking is adopted, to device self-powered, it is not necessary to external power supply and battery;
(2) do not powered restriction by single ended power supply, affected little by factors such as the fluctuation of load, harmonic wave, earth resistance and fault close angles;
(3) fault signature extracts and is effectively utilized primary fault transient information and to client information, can effectively solve single-phase grounded malfunction in grounded system of low current route selection and orientation problem.
Accompanying drawing explanation
Fig. 1 is the application schematic diagram of one embodiment of the invention.
Fig. 2 is the external structure schematic top plan view of one embodiment of the invention.
Fig. 3 is the external structure elevational schematic view of one embodiment of the invention.
Fig. 4 is the internal structure schematic diagram of one embodiment of the invention.
Detailed description of the invention
Below in conjunction with accompanying drawing and preferred embodiment, the present invention is more specifically described.
As it is shown in figure 1, be the schematic diagram being applied to power distribution network of the present embodiment. The device of the present embodiment is arranged on 35KV and each bus of following power distribution network and branch line, often 3 devices (corresponding the A phase of electric lines of force, B phase, C phase) can be installed by place, the global positioning system in device (GPS) is utilized to realize the precise synchronization of each point device internal sample data, then passing through short-distance wireless communication device concentration and be aggregated in a master device, master device is finally transmitted to backstage master station again through base station and the Internet of remote-wireless communication (3G/4G). Backstage master station adopts various fault decision algorithms and manual decision's system to realize faulty line selection and the location of fault.
Fig. 2 and Fig. 3 illustrates the external structure schematic diagram of the present embodiment. This device is completely insulated with electric lines of force, and no matter whether electric lines of force carries electric current can both be mounted and dismounted by opening-closing structure. The folding of device realizes by opening box screw rod 206, turns clockwise, and device upper cover 201, lower cover 204 two parts separate, and snap in electric lines of force, and another mistake hour hands rotate, and upper and lower part closes. And press tongue 202 can compress electric lines of force after device upper and lower covers closes. Inside device upper cover 201, lower cover 204, built-in current transformer is used for power taking and measurement. Electronic circuit in device is placed in the drawings in electrical installation box 203, has fin 209 for dispelling the heat simultaneously, and LED 208 indicates on the spot for fault, and built-in aerial 205 is then used for communicating. Additionally sim card slot 207 is for installing the SIM for remote-wireless communication (3G/4G). Additionally, whole device is except buckle power line portion, other parts have all done water-proofing treatment.
Fig. 4 is the present embodiment internal functional architecture schematic diagram. Wherein 300 is central processing unit (CPU). This processor adopts 32 low power processors, sensing power-supply circuit 301 electric energy exported is powered, and the clock accepting crystal oscillator 305 exports as work clock.Realize the real-time sampling to power line current by controlling high-precision adc 302, realize power line temperature collection by controlling temperature sensor. The data of sampling can stamp the time tag of unified global positioning system (GPS) 307, is then buffered in Large Volume Data buffer 306. Namely the logical line device 308 of available short-distance wireless realizes the data communication between neighboring devices, it is also possible to realized by remote-wireless communicator 309 and far-end background system mutual, it is achieved remote scheduling and monitoring.
301 is sensing power-supply circuit. This circuit completes to take energy function from power induction, powers to central processing unit 300 and every other circuit, it is achieved the self-powered of device, it is not necessary to external power supply and backup battery.
302 is high-precision adc. This analog-digital converter realizes the real-time sampling to power line current.
303 is temperature sensor. Temperature sensor adopts resistance temperature detection sensor, and this sensor can directly contact with electric lines of force, and it measures the temperature obtained can convert voltage signal to, and central controller can complete the sampling to voltage signal and storage, and is eventually converted into temperature data.
304 is digital to analog converter. Digital to analog converter is converted to analog voltage signal for central processing unit is calculated the clock jitter obtained from digital signal, thus going to control crystal oscillator, realizes the automatic frequency calibration of crystal oscillator.
305 is crystal oscillator. Crystal oscillator provides high-precision work clock to central processing unit, this crystal oscillator can carry out automatic frequency calibration (AFC) by the pps pulse per second signal that global positioning system exports, thus improving clock accuracy further, ensure the current sampling data precise synchronization of each infield, to ensure, the analysis of fault is correctly reliable.
306 is Large Volume Data buffer. Adopt Large Volume Data buffer, it is possible to provide up to the real-time data memory of a few hours, any moment breaks down, all can trace back to the real time data of a few hours before fault. It can be greatly lowered the requirement of real-time that fault data is processed by device on the one hand, also provides more decision-making foundation for accident analysis and location simultaneously.
307 is global positioning system (GPS). Central processing unit completes parsing and the management of the information such as the initialization to global positioning system, timing information, geographical coordinate. Adopt global positioning system, it is possible to stamp precise time label to sampled data, thus realizing the electricity sampling of each infield, measuring precise synchronization, ensure the correctness for fault location and the data of analysis and reliability.
308 is short-distance wireless communication device. Central processing unit completes the initialization to short range communicator and communication scheduling. Short-distance wireless communication device can realize the intercommunication mutually being arranged between the device of the present embodiment of adjacent, simplifies installation cost and communication cost, it is achieved be uniformly carried out data acquisition, distribution and the communication with far-end backstage by master device.
309 is remote-wireless communicator. Central processing unit completes the initialization to telecommunication device and communication scheduling. By remote-wireless communicator, it is possible to achieve the data communication of high speed between device and backstage, solve remote scheduling and long-range monitoring problem.
Utilizing function above device, the device of the present embodiment mainly achieves current monitoring, temperature monitoring, event record secondary failure positioning function.
(1) current monitoring
Power line current is monitored, it is possible to measured the electric current flow through in electrical lead by current transformer or Luo-coil.Luo-coil can export the voltage signal corresponding with electric current by integrator, and current transformer also can connect sampling resistor at outfan and obtain the voltage signal corresponding with electric current. In this embodiment, analog-digital converter is with 50 cycles per second, and electric current is sampled by the speed of each 256 sampling points of cycle, the central processing unit each cycle data calculating current virtual value (RMS) to sampling and each harmonic component. Interference Detection and analysis can be carried out in real time on the one hand, it is also possible to current flow virtual value and each harmonic value are reported backstage by timing, it is achieved remotely monitor.
(2) temperature monitoring
Power line temperature is monitored, it is possible to detects sensor by resistance temperature and detects the temperature of electrical lead. In this embodiment, after device is installed electric lines of force and closed, the top of temperature detecting sensor can contact with electrical lead, and meanwhile, the housing of this sensor and device is completely insulated on electric and heat energy. This temperature sensor can detect the conductor temperature of-40 degrees Celsius to+125 degrees Celsius, and produces voltage output signal corresponding with conductor temperature for central processing unit (CPU) collection.
(3) event record ripple
When power system generation disturbance, it is possible to record some cycle data before and after disturbance by oscillograph, for recalling analysis afterwards. In this embodiment, if power system generation disturbance, the present embodiment device can automatically be enrolled and preserve current waveform, device have employed high-resolution (12.8KHz sample frequency) and the analog-digital converter of high accuracy (16 bit data precision), adopt jumbo buffer simultaneously, the power line current data before disturbance a few hours can be reviewed, simultaneously the also disturbance event of recordable tens thousand of times.
(4) fault location
When electric lines of force breaks down, there is a lot of location algorithm based on transient state or stable state. In this embodiment, if power system generation disturbance, the device meeting automatic alarm of the present embodiment is to backstage. Simultaneously if it is determined that be that line current exceedes setting definite value, device can automatic bright light warn on the spot. First any disturbance all can be carried out the data of Selection and call relevant apparatus, then complete fault line selection and fault locating according to various resultant fault route selections and location algorithm (comprising difference current algorithm etc.) after occurring by manual decision's system on backstage.
The present embodiment adopts and opens box structure, it is achieved without the charged installation and removal having a power failure; Adopt the mode from power induction electric current power taking, to device self-powered; Adopt high-performance low-power-consumption processor, high-precision adc and software and hardware interference protection measure, it is ensured that gather reliability and the accuracy of signal; Adopt global positioning system (GPS)/BEI-DOU position system precision time service, it is ensured that the synchronicity of the sampled data of each device in universe; Utilize the pulse per second (PPS) information of alignment system, system work clock deviation is carried out automatic frequency calibration (AFC).
The present embodiment also proposed a kind of novel transient analysis method adopting difference current to calculate, this difference current algorithm utilizes the current information that the precise synchronization of neighboring devices is sampled to carry out difference operation, time properly functioning, this difference is only small close to zero, and once this difference exceedes certain threshold value (thresholding can set) according to practical situation it is determined that for there occurs fault, thus completing fault line selection and fault locating; And it is a kind of based on the distribution of stable state homopolar power and the novel steady-state analysis method of manual decision's system, this steady-state analysis method utilizes transformer neutral point place, or the current information that the residual voltage of threephase potential transformer open delta output and the sampling of three-phase installation precise synchronization obtain, can the zero sequence power direction scattergram of quasi real time guiding system each point on backstage, thus judging faulty spur, above two method overcomes the deficiency of tradition route selection and location algorithm in the past;After the device starting element of this enforcement triggers, start to store the Temporal Data before and after the triggered time and steady state data, carry out troubleshooting and differentiation.
The present embodiment utilizes adaptive threshold and continuous several times judgement mode, solves erroneous judgement and problem of failing to judge; When the present embodiment carries out failure wave-recording, carry out comprehensively analyzing and judging to fault by background system; This enforcement adopts the data buffer of Large Copacity (Giga-bit), reduces the requirement of real-time of synchrodata scheduling between each device, unified to background process; The present embodiment can remotely monitor electric lines of force working condition by background system, including power line current, harmonic wave, temperature, for power system to power monitoring circuit and optimization; The present embodiment passes through background system, it is achieved the aerial online software upgrade of device.
It is more than the preferred embodiment of the present invention, the improvement done under the premise without departing from the technology of the present invention principle and deformation, also regards as protection scope of the present invention.
Claims (8)
1. an intelligent grid sensing device, it is characterised in that it includes:
Central processing unit, for passing through the real-time sampling controlling high-precision adc realization to power line current, realize power voltage line collection by controlling temperature sensor and be converted into temperature data, and to the parsing of the initialization of global positioning system device, timing information and geographic coordinate information and process, and to the initialization of short range communicator and telecommunication device and communication scheduling;
Global positioning system, for loading precise time label to sampled data;
Large Volume Data buffer, for storing electric lines of force at the real time temperature set in time range, electric current and voltage data;
Temperature sensor, this sensor directly contacts with electric lines of force, for converting the temperature of the electric lines of force recorded to voltage signal;
High-precision adc, for power line current real time data sampling;
Short-distance wireless communication device, is used for the intercommunication mutually being arranged between the intelligent grid sensing device of adjacent, then by master device, the intelligent grid sensing device of adjacent is uniformly carried out data acquisition, distribution and the communication with far-end backstage;
Remote-wireless communicator, for the data communication between intelligent grid sensing device and backstage;
Digital to analog converter, for being converted to analog voltage signal by the clock jitter calculated on central processing unit from digital signal; And
Crystal oscillator, for providing high-precision work clock to central processing unit, carries out automatic frequency calibration according to the pps pulse per second signal of global positioning system output.
2. intelligent grid sensing device according to claim 1, it is characterized in that, described central processing unit is connected with global positioning system, Large Volume Data buffer, temperature sensor, high-precision adc, short-distance wireless communication device, remote-wireless communicator and digital to analog converter, described digital to analog converter connects crystal oscillator, and described crystal oscillator is connected with central processing unit.
3. intelligent grid sensing device according to claim 1, it is characterised in that it also includes sensing power-supply circuit, in order to from power induction power taking and power to central processing unit and other devices.
4. intelligent grid sensing device according to claim 1, it is characterised in that described central processing unit adopts 32 low power processors.
5. intelligent grid sensing device according to claim 1, it is characterised in that described temperature sensor adopts resistance temperature detection sensor.
6. according to the arbitrary described intelligent grid sensing device of claim 1 ~ 5, it is characterised in that described analog-digital converter sampling rate is 50 cycles per second, each cycle 256 sampling points of sampling.
7. according to the arbitrary described intelligent grid sensing device of claim 1 ~ 5, it is characterised in that described temperature sensor detection conductor temperature ranges for-40 ~ 125 DEG C.
8. according to the arbitrary described intelligent grid sensing device of claim 1 ~ 5, it is characterized in that it also includes out box screw rod, upper cover and lower cover, described upper cover and lower cover are combined closely, described in open box screw rod and be located at lower cover bottom, and described in open top and the upper cover inner faces contact of box screw rod.
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Cited By (1)
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| TWI740336B (en) * | 2019-12-30 | 2021-09-21 | 台灣新光保全股份有限公司 | Warning system |
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