CN107681699A - A kind of grid-connected detection means of distributed power source and method - Google Patents
A kind of grid-connected detection means of distributed power source and method Download PDFInfo
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- CN107681699A CN107681699A CN201711239311.3A CN201711239311A CN107681699A CN 107681699 A CN107681699 A CN 107681699A CN 201711239311 A CN201711239311 A CN 201711239311A CN 107681699 A CN107681699 A CN 107681699A
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/381—Dispersed generators
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
- G01R15/18—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using inductive devices, e.g. transformers
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/388—Islanding, i.e. disconnection of local power supply from the network
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Supply And Distribution Of Alternating Current (AREA)
Abstract
The invention discloses a kind of grid-connected detection means of distributed power source, including electric parameter signal acquisition module, forcing frequency generation module, master control and analysis module and human-computer interaction module：Electric parameter signal acquisition module receives master control and the corresponding electric parameter of analysis module instruction acquisition；Forcing frequency generation module specifies the interference electric current of size according to the instruction generation of master control and analysis module；Master control and analysis module reception processing personnel instruct and control corresponding module to complete work；Human-computer interaction module is used for human users and result is shown.The present invention discloses a kind of detection method based on the detection means simultaneously, and distributed grid-connected detection project is divided into Power Quality Detection project and isolated island detection project by the detection method, by being operable to complete detection work on detection means.The device and method that the present invention announces is developed for small-sized household, has filled up the blank of the grid-connected detection field of distributed power source in this regard.
Description
Technical field
The invention belongs to the grid-connected detection technique field of distributed power source in power system, and in particular to a kind of small-sized household, which is used, to be divided
Cloth power grid device and method.
Background technology
In recent years, the appearance of global energy crisis promotes the development of generation of electricity by new energy, and distributed power source is as power network end
A kind of power supply with small capacity hold, near load, for improving energy utilization rate, solving the side such as electrical problem from far-off regions
There is positive effect in face.At present, develop using photovoltaic as the distributed power source industry of representative in China's power industry it is swift and violent, so
And for the angle of system for distribution network of power safe operation, distributed power source access power distribution network can be to many sides of power distribution network
Face has an impact, and common are the quality of power supply, electric network reliability, distribution loss, relay protection, Electric Power Network Planning etc., therefore, to dividing
Cloth power supply carries out grid-connected Characteristics Detection and just seems very necessary.For the grid-connected detection field of distributed power source, home and abroad is all
Correlative study and practice are carried out.It is still at an early stage at present because distributed power source development in China's is later, it is domestic right at present
The research of distributed power source is mostly focused on power supply in itself, less to its grid-connected context of detection research.For such case, country
Grid company, which has been put into effect, to be included《Distributed power source accesses power distribution network test specification》More ministerial standards inside, but studies in China still collects
In in theoretical field, deficiency is studied in terms of the realization of distributed power source.The country is had been developed that for MW level large-sized photovoltaics at present
The portable grid-connected detecting system of generating.But the test platform is more comprising equipment, test site space requirement is excessive, uncomfortable
Family photovoltaic power generation apparatus for kW levels.Therefore, for kW levels the grid-connected measuring technology of family distributed power source small-sized survey
The correlative study of examination equipment and technical scheme just seems very necessary.
The content of the invention
For deficiencies of the prior art, the present invention proposes a kind of grid-connected detection means of distributed power source and side
Method, its technical scheme are：
A kind of grid-connected detection means of distributed power source, it is characterised in that generated including electric parameter signal acquisition module, forcing frequency
Module, master control and analysis module and human-computer interaction module：
The electric parameter signal acquisition module is connected with master control and analysis module, provided with the voltage for gathering site voltage signal to be measured
Transformer and the current transformer for gathering site current signal to be measured；
The forcing frequency generation module is connected with master control and analysis module, generates the interference letter for active alone island detection
Number；
The master control and analysis module are used for：The electric signal of electric parameter signal acquisition module output is received, and carries out Treatment Analysis；
The measured value and Treatment Analysis result for receiving electric signal are sent to human-computer interaction module；Receive the control of human-computer interaction module transmission
Instruction；The instruction transmitted according to human-computer interaction module or preset instructions coordinate or control electric parameter signal acquisition module, disturbance frequency
The work operation of rate generation module；
The human-computer interaction module is connected with master control and analysis module, for showing the letter needed for grid-connected detection to controllers
Cease, and the operational order of controllers is transmitted to master control and analysis module.
On the basis of such scheme, further improve or preferable scheme also includes：
After the electric signal that the master control and analysis module export to electric parameter signal acquisition module carries out analog-to-digital conversion, believe from voltage
Frequency information and amplitude information are extracted in number, FFT is used to current signal（Fast fourier transform algorithm, fast fourier
transform algorithm）Or DFT（Discrete Fourier transform, Discrete Fourier Transform）Mode is extracted
Harmonic information, the electric signal measurement value of collection is calculated into its deviation compared with standard value.
The forcing frequency generation module includes frequency generator and current amplifier, adjustable for producing frequency and amplitude
Interference electric current.
The grid-connected detection means of distributed power source, provided with a moveable platform, the parameter signals acquisition module, disturbance
Frequency generation module, master control and analysis module and human-computer interaction module are arranged on the moveable platform.
A kind of detection method based on the grid-connected detection means of distributed power source as described above, including Power Quality Detection and orphan
Detect on island, it is characterised in that：
The Power Quality Detection detects including voltage detecting harmonic：
The step of voltage detecting is：Site voltage magnitude to be measured is gathered, compares the voltage of collection value and specified line voltage
Amplitude, and difference is calculated, judge whether site quality of voltage to be measured meets to require according to the difference；
The step of harmonic detecting is：Gather the current value of site to be measured, by the modes such as FFT, DFT to electric current at
Reason, calculates its THD, judges whether harmonic wave meets to require according to THD；
The isolated island detection includes the detection of passive type isolated island and active alone island detection：
The step of passive type isolated island detection is：Set on bulk power system with reference to site, gather the reference site with dividing
The voltage magnitude and frequency of cloth power-supply system site to be measured, difference is drawn by comparing, and judges whether difference allows in regulation
In the range of, judge whether the distributed power supply system is islet operation with this；
The step of active alone island detection is：Collection calculates the electric voltage frequency f of distributed power supply system site to be measured, to
The injected frequency is f+ Δs f current disturbing signal, and Δ f ≠ 0 monitors whether the site electric voltage frequency to be measured starts Cycle by Cycle
Skew, and islet operation is determined whether accordingly.
Beneficial effect：
The invention provides the grid-connected detection means of distributed power source and the detection method based on described device, pass through extraction and simplify
Necessary detection project and detecting step, the purpose of light portable, economic flexible can be achieved, connect effectively to solve distributed power source
Enter the safety and stability problem after power distribution network, power quality problem, Power Control Problem, exception response and anti-isolated island protection problem to carry
Beneficial thinking is supplied, on the premise of power system security stable operation is ensured, after improving distributed power source access power distribution network
System economy and operational efficiency, solve the grid-connected detection field of current distributed power source and realizing small-sized household scale distribution formula
The problem of detection means and detection method of power grid detection lack.
Brief description of the drawings
Fig. 1 is the grid-connected structure of the detecting device schematic diagram of distributed power source；
Fig. 2 is the functional block diagram of master control and analysis module；
Fig. 3 is distributed power source and network detecting method overhaul flow chart.
Embodiment
For the technical scheme and operation principle that the present invention is furture elucidated, below in conjunction with the accompanying drawings with specific embodiment to this
Invention is described further.
The grid-connected detection means of a kind of distributed power source as shown in Figure 1, including electric parameter signal acquisition module, forcing frequency
The part such as generation module, master control and analysis module, human-computer interaction module.
The electric parameter signal acquisition module is connected with master control and analysis module, and site to be measured is gathered by voltage transformer
Voltage signal, the current signal of site to be measured is gathered by current transformer.
The forcing frequency generation module is connected with master control and analysis module, provided with frequency generator and current amplifier,
For producing frequency and the adjustable interference electric current of amplitude, it is mainly used in the interference signal being generated for use in active alone island detection.
The master control and analysis module are mainly used in：The electric signal of electric parameter signal acquisition module output is received, and is carried out
Treatment Analysis；It, which is sent, to human-computer interaction module receives the measured value and Treatment Analysis result of electric signal；Receive man-machine interaction mould
The instruction of block transmission；The instruction transmitted according to human-computer interaction module or preset instructions coordinate or control electric parameter signal acquisition mould
The work operation of block, forcing frequency generation module.
In the present embodiment, the master control and analysis module are integrated on one piece of MCU, be whole device control centre and
Data processing centre, as shown in Fig. 2 master control and analysis module are divided into four functional areas：Interface function area, Power Quality Detection
Functional areas, passive type isolated island detection function area and active alone island detection function area.
The interface function area is responsible for the information transmission with human-computer interaction interface, and its function includes receiving from man-machine interaction mould
Block is transmitted through the controllers instruction come, by identify in the other three kinds of functional areas of controllers instruction calls corresponding functional areas come
Complete test job；And the result of each functional module is received, and be processed into prescribed form and pass to human-computer interaction module
Shown.
The quality of power supply that survey grid point is responsible for treating in Power Quality Detection functional areas is detected, including quality of voltage detection and
Harmonic quality detects.Quality of voltage detection extracts voltage magnitude by using electric parameter signal acquisition module collection voltages signal
Information and frequency information, and its difference with setting is calculated, the difference calculated is finally transmitted to interface function area.Harmonic wave matter
Measure detection function area and current signal is gathered by using electric parameter signal acquisition module, current signal is carried out using DFT or FFT
Its harmonic information is extracted in processing, and calculates THD, and the THD calculated finally is transmitted into interface function area.
By detecting voltage magnitude, phase and frequency, to differentiate, whether examining system is lonely in passive type isolated island detection function area
Run on island.It passes through electric parameter signal acquisition module collection voltages signal, the voltage magnitude and frequency of extraction institute survey grid point first
Information, then calculate its difference with setting, finally by judge difference judge system whether islet operation, and by difference
Interface function area is transmitted to judged result.Active Function detection gathers the electricity of institute's survey grid point by electric parameter signal acquisition module
Signal is pressed, its current frequency f is extracted and passes to interface function area and shown, then the Δ f of reception staff's setting and interference
Current amplitude A, it is f+ Δs f to start forcing frequency generation module generation frequency（Δf≠0）, amplitude be A interference electric current, simultaneously
The frequency f changes of the tested site of monitoring, by determination frequency whether Cycle by Cycle skew come judgement system whether islet operation, and will
Interface function area is transmitted to when the frequency and differentiation fructufy of measured point to be shown
The human-computer interaction module is connected with master control and analysis module, provided with touch-screen and corresponding controlling switch, for control
Personnel processed show the information needed for grid-connected detection, such as the processing of the measured value of site electric signal to be measured and master control and analysis module point
Result etc. is analysed, and the operational order of controllers is transmitted to master control and analysis module.Fig. 3 is distributed power source and network detecting method
Overhaul flow chart, controllers are selected by the display interface of the human-computer interaction module of the grid-connected detection means of the distributed power source
Power Quality Detection, the detection of passive type isolated island or active detection project, and can be with real time inspection testing result；In active orphan
In the detection project of island, controllers need the size according to institute's survey grid point current frequency setting interference electric current frequency and amplitude.
In the present embodiment, the detection means is additionally provided with a portable moveable platform, the parameter signals acquisition module,
Forcing frequency generation module, master control and analysis module and human-computer interaction module are arranged on the moveable platform.
Based on the detection method of the grid-connected detection means of distributed power source as described above, including Power Quality Detection and isolated island inspection
The projects such as survey.
The Power Quality Detection includes voltage detecting harmonic quality testing.
The step of voltage detecting is：
1）Gather distributed power supply system site voltage magnitude to be measured；
2）Comparison step 1）Collection value and the voltage magnitude of specified line voltage, and calculate difference；
3）According to step 2）Obtained difference judges whether site quality of voltage to be measured meets to require.
The step of harmonic quality detection is：
1）Gather the current parameters of site to be measured；
2）Electric current is handled by modes such as FFT, DFT, calculates its THD（Total harmonic distortion, Total Harmonic
Distortion）, judge whether harmonic wave meets to require according to THD.
The isolated island detection includes the detection of passive type isolated island and active alone island detection.
The step of passive type isolated island detection is：
1）The voltage for reference to site, gathering the reference site and distributed power supply system site to be measured is set on bulk power system
Amplitude and frequency；
2）Pass through comparison step 1）Collection value, obtain the difference of distributed power supply system and bulk power system voltage magnitude and frequency
Value；
3）Judgment step 2）Obtained difference judges the distributed power supply system whether in the range of relevant regulations permission with this
Whether it is islet operation.
The step of active alone island detection is：
1）Collection calculates the electric voltage frequency f of distributed power supply system site to be measured；
2）To the current disturbing signal that the site injected frequency to be measured is f+ Δs f, Δ f ≠ 0；
3）Monitor whether the site electric voltage frequency to be measured starts Cycle by Cycle skew, and determine whether islet operation accordingly.
General principle, principal character and the advantages of the present invention of the present invention has been shown and described above.The technology of the industry
Personnel are it should be appreciated that the present invention is not limited to the above embodiments, and the simply explanation described in above-described embodiment and specification is originally
The principle of invention, without departing from the spirit and scope of the present invention, various changes and modifications of the present invention are possible, the present invention
Claimed scope is by appended claims, specification and its equivalent thereof.
Claims (5)
1. a kind of grid-connected detection means of distributed power source, it is characterised in that given birth to including electric parameter signal acquisition module, forcing frequency
Into module, master control and analysis module and human-computer interaction module：
The electric parameter signal acquisition module is connected with master control and analysis module, provided with the voltage for gathering site voltage signal to be measured
Transformer and the current transformer for gathering site current signal to be measured；
The forcing frequency generation module is connected with master control and analysis module, generates the interference letter for active alone island detection
Number；
The master control and analysis module are used for：The electric signal of electric parameter signal acquisition module output is received, and carries out Treatment Analysis；
The measured value and Treatment Analysis result for receiving electric signal are sent to human-computer interaction module；Receive the control of human-computer interaction module transmission
Instruction；The instruction transmitted according to human-computer interaction module or preset instructions coordinate or control electric parameter signal acquisition module, disturbance frequency
The work operation of rate generation module；
The human-computer interaction module is connected with master control and analysis module, for showing the letter needed for grid-connected detection to controllers
Cease, and the operational order of controllers is transmitted to master control and analysis module.
A kind of 2. grid-connected detection means of distributed power source according to claim 1, it is characterised in that：
After the electric signal that the master control and analysis module export to electric parameter signal acquisition module carries out analog-to-digital conversion, believe from voltage
Frequency information and amplitude information are extracted in number, harmonic information is extracted using FFT or DFT modes to current signal, by the electricity of collection
Signal measurements calculate its deviation compared with standard value.
A kind of 3. grid-connected detection means of distributed power source according to claim 1, it is characterised in that：
The forcing frequency generation module includes frequency generator and current amplifier, adjustable dry for producing frequency and amplitude
Disturb electric current.
4. the grid-connected detection means of a kind of distributed power source according to claim 1, it is characterised in that removable flat provided with one
Platform, the parameter signals acquisition module, forcing frequency generation module, master control and analysis module and human-computer interaction module are arranged on institute
State on moveable platform.
5. a kind of detection method based on the grid-connected detection means of distributed power source any one of claim 1-4, including electricity
Energy quality testing and isolated island detection, it is characterised in that：
The Power Quality Detection detects including voltage detecting harmonic：
The step of voltage detecting is：Site voltage magnitude to be measured is gathered, compares the voltage of collection value and specified line voltage
Amplitude, and difference is calculated, judge whether site quality of voltage to be measured meets to require according to the difference；
The step of harmonic detecting is：Gather the current value of site to be measured, by the modes such as FFT, DFT to electric current at
Reason, calculates its THD, judges whether harmonic wave meets to require according to THD；
The isolated island detection includes the detection of passive type isolated island and active alone island detection：
The step of passive type isolated island detection is：Set on bulk power system with reference to site, gather the reference site with dividing
The voltage magnitude and frequency of cloth power-supply system site to be measured, difference is drawn by comparing, and judges whether difference allows in regulation
In the range of, judge whether the distributed power supply system is islet operation with this；
The step of active alone island detection is：Collection calculates the electric voltage frequency f of distributed power supply system site to be measured, to
The injected frequency is f+ Δs f current disturbing signal, and Δ f ≠ 0 monitors whether the site electric voltage frequency to be measured starts Cycle by Cycle
Skew, and islet operation is determined whether accordingly.
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Cited By (2)
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| CN110161430A (en) * | 2019-05-31 | 2019-08-23 | 苏州迅鹏仪器仪表有限公司 | DC power supply intelligent comprehensive monitoring device |
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Application publication date: 20180209 |