CN107884654A - A kind of transformer station's multiple spot equipment for monitoring power quality and method - Google Patents
A kind of transformer station's multiple spot equipment for monitoring power quality and method Download PDFInfo
- Publication number
- CN107884654A CN107884654A CN201711277048.7A CN201711277048A CN107884654A CN 107884654 A CN107884654 A CN 107884654A CN 201711277048 A CN201711277048 A CN 201711277048A CN 107884654 A CN107884654 A CN 107884654A
- Authority
- CN
- China
- Prior art keywords
- mrow
- msub
- voltage
- harmonic
- current
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Remote Monitoring And Control Of Power-Distribution Networks (AREA)
Abstract
The invention belongs to substation equipment technical field, disclose a kind of transformer station's multiple spot equipment for monitoring power quality and method, monitoring method is detected by voltage and current and modulate circuit, the collection of three-phase voltage and current signal is completed by DSP itself AD conversion port, handled through internal algorithm, obtain each secondary voltage and current harmonic data, and analysis voltage, current-symmetrical degree, power factor (PF), the power quality parameter of total harmonic distortion;Quality of power supply result of calculation is continuously written into designated memory cell, then host computer is sent to by MODBUS rtu protocols and analyzed and processed.Present invention arrangement multipoint mode equipment for monitoring power quality, complete the transmission of multiple spot Power Quality Detection data using MODBUS agreements and information is managed concentratedly, each node quality of power supply state of analysis transformer station;And each state can be alarmed, the potential pollution source of the quality of power supply is analyzed, support is provided for substation operation maintenance.
Description
Technical field
The invention belongs to substation equipment technical field, more particularly to a kind of transformer station's multiple spot equipment for monitoring power quality and
Method.
Background technology
With in power system nonlinear load user increase with more users to the quality of power supply propose it is higher and higher
It is required that substation distribution network electric energy quality monitor and extensively paid attention in power system.Power network department ensures on this basis
Power network reliability service, while user is monitored to power network exhaust emission situation;Some quality of power supply sensitivity enterprises can understand electricity whereby
Net power supply quality, study and judge its influence to sensitive equipment;It can be then monitored to electric network pollution large enterprise to reach to power network blowdown
Mark situation, whether effective it is examined to compensate equipment;The objective data that the equipment preserves simultaneously, power network can also be used as to be sent out with client
Judging basis during raw controversial issue.
In summary, the problem of prior art is present be:
Existing electric energy quality for substation monitoring task is mostly the detection of single-point task, is generally used for the inspection to key equipment
Survey, seldom concern causes the source of the quality of power supply, and potential power quality problem is positioned, and function is more single.
Existing each Power Quality Detection equipment often independent operating, lack between the data of collection It is not necessary to contact, lack pair
The centralized management and analysis of multiple spot Power Quality Detection data.If the Distributed Multi electric energy based on specific network protocols can be established
Quality detection device, and parsed by centralized detecting with managing each node power quality data between each power quality data
Incidence relation, by specific algorithm, the state of each quality of power supply is determined, the data progress of catastrophe failure to the quality of power supply be present
Prediction and alert process;And the positioning of some pollution sources of electrical energy quality can be completed, for power transformation according to the incidence relation of each data
Stand put into operation, operation maintenance and maintenance have especially positive directive function, for look-ahead possible breakdown, detect power grid pollution
Dye situation, the validity for assessing power quality compensator, the pollution situation responsibility distribution etc. for assessing electricity consumption enterprise, all may be used
To provide important reference data.
The content of the invention
The problem of existing for prior art, the invention provides a kind of transformer station's multiple spot equipment for monitoring power quality and side
Method.
The present invention is achieved in that a kind of transformer station's multiple spot electric energy quality monitoring method, transformer station's multiple spot electric energy
Quality monitoring method is detected by voltage and current and modulate circuit, and three-phase voltage is completed by DSP itself AD conversion port
With the collection of current signal, handled through internal algorithm, obtain each secondary voltage and current harmonic data, and analysis voltage, electric current pair
Title degree, power factor (PF), the power quality parameter of total harmonic distortion;Quality of power supply result of calculation is continuously written into and specifies storage single
Member, then host computer is sent to by MODBUS rtu protocols and analyzed and processed.
Further, transformer station's multiple spot electric energy quality monitoring method specifically includes:
Using DSP28335 as control core, by voltage and current modulate circuit, by three-phase voltage and current signal pick-up
Into the low voltage single-pole DC form for the AD port level requirements for meeting DSP;
By the arithmetic programming inside DSP AD conversion port, according to the three-phase voltage current numerical value of collection, with defined
In the cycle, calculate less than 25 times each harmonic contents of three-phase voltage and electric current, calculate three-phase voltage and current balance type degree, power because
Number, and be stored in by defined data format in internal storage;
MODBUS RTU communications protocol is followed, the multi computer communication of master-slave mode is completed using main frame calling slave mode;
Host computer writes operation and control interface using ForceControl configuration software, carries out the extraction of power quality parameter, quantifies, and unit becomes
Change;
Upper computer software algorithm is write, adjusts power quality parameter alarm threshold value, it is exceeded to threshold value in power quality parameter
Parameter carries out color, audible alarm prompting;
During multimetering, according to power quality parameter numerical values recited, the direction of prediction power quality problem potential pollution source
Distribution.
Another object of the present invention is to provide a kind of transformer station's multiple spot equipment for monitoring power quality to include:
DSP28335 controllers, for transformer station's multiple spot electric energy quality monitoring and control operation program;
Modulate circuit, high-voltage great-current analog signal is first converted into low pressure low current AC signal, then filled through AD conversion
Put and be converted into digital quantity and calculated;12 AD conversion ports are carried using DSP;
Multi-point communication interface:For completing the remote information gathering of multiple monitoring terminals;
Power quality parameter computing module,
For calculating each harmonic content in voltage and current;
Synchronized signal acquisition module, grid phase information is obtained by three-phase software phlase locking principle;Become according to coordinate
The principle changed, three-phase voltage resultant vector usSize it is constant when, the u under synchronous rotating framesQ axis components usqReflect
D axles and line voltage usPhase relation;Work as usqWhen=0, line voltage usWith the same phase of d axles;By controlling usq=0 is used to realize
Both same-phases;By zero and usqAfter making the difference, ω is obtained through pi regulatorerr, with reference frequency ωNAfter comparing, by integrating,
Obtain pll phase angle θ;
MODBUS software protocol modules, master-slave mode multi computer communication system is established using RS485 networks, by main frame calling from
Machine, slave response mode are communicated;
Multiple spot detects and harmonic source location module, for positioning harmonic source and division harmonic contributions;And it is based on harmonic wave work(
Rate direction of tide determines harmonic source orientation.
Another object of the present invention is that providing a kind of power quality parameter computational methods includes:
Using the discrete fft algorithm of recurrence,
A cycle is T, and angular frequency is ω periodic signal X (t), if carrying out discrete sampling, each periodic sampling points
For N, sampling period τ, then periodic signal is expressed as:
N is the multiple proportion of the signal and fundamental signal decomposed in formula, An and Bn the shaking in n times of fundamental frequency that be periodic signal
Width;M is sampled point sequence number, and k is any one in N number of sampled point, and x (k τ) is the numerical value on k-th of sampled point.
In a cycle calculating process, since fixed starting point m=0, then fortune is simultaneously participated in N-1 data thereafter
Calculate;Likewise, if N number of sampled value before known present sample i, above-mentioned sampling period are then equally expressed as:
The initial data signal of N sampled value, N number of to having between sampled point i before m=i-N+1 is sampled point i in above formula
Data;The meaning of other symbols is consistent with description above.
Recurrence is carried out, the characteristic in binding signal cycle obtains:
So, if monitoring signals are periodic signal, if An (i) represents the result of spectrum analysis of this calculating, if having known
The result An (i-1) of road last time spectrum analysis, it is possible to reference to this to periodic signal in this sampled value X (i τ) and at it
Sampled value X [(i-N) τ] before a complete cycle, then substitute into above formula and can be obtained by this result of spectrum analysis An
(i).Same reason can obtain this Bn (i) according to last time analysis result.
Relative to the direct computing of fft algorithm is directly used, the amount of calculation of the formula is smaller, and calculating speed is faster.
Another object of the present invention is that provide a kind of multiple spot detection includes with harmonic source location method:
Power Quality Detection unit PQU harmonic source is divided into forward and backward;Zs is PQU forward direction equiva lent impedance, and Zc is
Backward equiva lent impedance;Harmonic impedance Z=Zs+Zc=jX, X are total harmonic wave reactance;Then harmonic power backward PQU is:
P=UsIcos θ=UsUcsinδ/X;
Wherein θ is UsLeading current I phase, δ are system side and user-side harmonic source phase difference;When positive and negative values occurs in P
When, harmonic wave is from not homonymy.
Advantages of the present invention and good effect are:
The present invention is directed to the key position of each node of transformer station, arranges multipoint mode equipment for monitoring power quality, utilizes
MODBUS agreements complete the detection of the multiple spot quality of power supply and information is managed concentratedly, each node quality of power supply state of analysis transformer station;
The present invention utilizes the periodic characteristic of power network signal, improves the rudimentary algorithm of Harmonics Calculation, merely with last result, this sampling
Data and corresponding last periodic sampling data, it is possible to accordingly result is obtained, due to traditional n times data need not be used to adopt
Collect the mode of simultaneously accumulation calculating, required time is shorter, and algorithm performs efficiency improves more than 50%.Assisted in the present invention using MODBUS
View transmission gathered data, distinguishes each node power quality data by address code, has preferable autgmentability, by means of RS485
Network, 256 partial node electric energy acquisition equipment can be at most extended, form distributed data acquisition network.Utilize host computer
The software systems of Development of Configuration Software, concentrated collection and information can be carried out to the quality of power supply of each monitoring point device, pass through setting
Alarm threshold value, the alert data more than secure threshold is alarmed by modes such as color, sound, auxiliary related personnel enter
Row maintenance, analysis, test etc..Upper computer software has certain quality of power supply detection and localization function, with reference to the distribution of each node
Topological relation, by the forward direction for calculating each PQU qualities of power supply nodal test unit and backward impedance, in conjunction with the resistance of adjacent node
It is anti-to be compared calculating, judge the potential site of the qualities of power supply such as harmonic wave, instruct staff to find the pollution of power network major harmonic
The distribution in source, is administered for follow-up electric energy and responsibility is distinguished and provides technical support.
Brief description of the drawings
Fig. 1 is transformer station's multiple spot equipment for monitoring power quality schematic diagram provided in an embodiment of the present invention.
Fig. 2 is voltage transmission and modulate circuit figure provided in an embodiment of the present invention.
Fig. 3 is multi computer communication interface schema provided in an embodiment of the present invention.
Fig. 4 is synchronized signal of change figure provided in an embodiment of the present invention.
Fig. 5 is harmonic power direction provided in an embodiment of the present invention positioning schematic.
Fig. 6 is the harmonic source location method flow diagram provided in an embodiment of the present invention calculated based on harmonic power.
Fig. 7 is synchronized signal detection figure provided in an embodiment of the present invention.
Fig. 8 is the sample sequence figure of periodic signal provided in an embodiment of the present invention.
Embodiment
In order to make the purpose , technical scheme and advantage of the present invention be clearer, with reference to embodiments, to the present invention
It is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, it is not used to
Limit the present invention.
Existing transformer station's multiple spot equipment for monitoring power quality does not complete the multiple spot quality of power supply using MODBUS agreements
Detection is managed concentratedly with information, each node quality of power supply state of analysis transformer station;Nor each state can be alarmed;No
It can analyze the potential pollution source of the quality of power supply simultaneously by more each node power quality data, carried for substation operation maintenance
For supporting.
The application principle of the present invention is further described below in conjunction with the accompanying drawings.
As shown in figure 1, transformer station's multiple spot electric energy quality detection device provided in an embodiment of the present invention, including:
DSP28335 controllers, for transformer station's multiple spot electric energy quality monitoring and control operation program;
Modulate circuit, high-voltage great-current analog signal is first converted into low pressure low current AC signal, then filled through AD conversion
Put and be converted into digital quantity and calculated;12 AD conversion ports are carried using DSP;
Multi-point communication interface:For completing the remote information gathering of multiple monitoring terminals;
Power quality parameter computing module,
For calculating each harmonic content in voltage and current;
Synchronized signal acquisition module, grid phase information is obtained by three-phase software phlase locking principle;Become according to coordinate
The principle changed, three-phase voltage resultant vector usSize it is constant when, the u under synchronous rotating framesQ axis components usqReflect
D axles and line voltage usPhase relation;Work as usqWhen=0, line voltage usWith the same phase of d axles;By controlling usq=0 is used to realize
Both same-phases;By zero and usqAfter making the difference, ω is obtained through pi regulatorerr, with reference frequency ωNAfter comparing, by integrating,
Obtain pll phase angle θ;
MODBUS software protocol modules, master-slave mode multi computer communication system is established using RS485 networks, by main frame calling from
Machine, slave response mode are communicated;
Multiple spot detects and harmonic source location module, for positioning harmonic source and division harmonic contributions;And it is based on harmonic wave work(
Rate direction of tide determines harmonic source orientation.
With reference to concrete analysis, the invention will be further described.
Transformer station's multiple spot power quality detection method provided in an embodiment of the present invention, controlled by core design of DSP28335
Device, by the voltage and current modulate circuit of design, by three-phase voltage and current signal pick-up into meeting DSP AD port levels
It is required that low voltage single-pole DC form.
Inside, according to the three-phase voltage current numerical value of collection, with the defined cycle, calculates three-phase voltage by arithmetic programming
With less than 25 times each harmonic contents of electric current, three-phase voltage and current balance type degree, power factor, and the data as defined in are calculated
Form is stored it in internal storage;
MODBUS RTU communications protocol is followed, the multi computer communication of master-slave mode is completed using main frame calling slave mode;It is upper
Machine writes operation and control interface using ForceControl configuration software, realizes the extraction of power quality parameter, quantifies, identity transformation etc.;
Upper computer software algorithm is write, power quality parameter alarm threshold value is can adjust, threshold value in power quality parameter is surpassed
Mark parameter and carry out the alarms such as color, sound;
During multimetering, according to power quality parameter numerical values recited, the direction of prediction power quality problem potential pollution source
Distribution.
Transformer station's multiple spot electric energy quality detection device provided in an embodiment of the present invention mainly have Power Quality Detection hardware and
Positioning software is assessed to form.Wherein hardware uses DSP28335 as key control unit, mutual using voltage transformer and electric current
Sensor obtains the voltage and current information of key node in transformer station;By voltage and current size and polarity modulate circuit, send
Enter the quantization that DSP itself AD ports carry out three-phase simulation voltage and analog current signal.DSP indoor designs software algorithm, calculate
Each harmonic composition and content, analysis obtain the main power quality parameters such as voltage, current-symmetrical degree, power factor.Hardware with
Modular form is arranged on Substation Bus Arrangement main node, forms multiple spot arrangement form;Each module configures RS485 communications and connect
Mouthful, form RS485 communication networks.Communicated between main frame and slave using MODBUS rtu protocols, RS485 passes through SP481
The matching of USB and 485 bus levels is realized with FT232R chips.Host computer interface is developed using ForceControl configuration software, is had each
The power quality parameters such as secondary voltage, current harmonics composition are shown, three-phase waveform symmetry are shown, alarm threshold value can be set, work as phase
Answer parameter exceeded, corresponding alarm can be sent;Under multipoint acquisition pattern, pass through more each main power quality parameter size
And direction, it is preliminary to indicate quality of power supply potential site, it is easy to staff to grasp power network quality of power supply state, auxiliary power grid operation
With service work.
Below in conjunction with the accompanying drawings and specific embodiment is further described to the application principle of the present invention.
1st, electric energy quality monitoring method,
For ease of the needs of multimetering, scheme uses modular mentality of designing, using DSP28335 as control core, if
Voltage and current detection and modulate circuit are counted, by DSP itself AD conversion port completion three-phase voltage and adopting for current signal
Collection, is handled through internal algorithm, obtains each secondary voltage and current harmonic data, and can analysis voltage, current-symmetrical degree, power because
The exemplary power mass parameter such as element, total harmonic distortion.Quality of power supply result of calculation is continuously written into designated memory cell, then passed through
MODBUS rtu protocols are sent to host computer analyzing and processing.
2nd, hardware circuit:
In the hardware circuit design of electric energy quality test instrument, designed most with modulate circuit with the conversion of multichannel AC voltage x current
For key.
2.1 modulate circuit:
Detection for AC analogue voltage and current, high-voltage great-current analog signal is first converted into low pressure low current and handed over
Signal is flowed, then is converted into digital quantity through a/d conversion device and is calculated.Directly 12 are carried from hardware circuit angle is simplified using DSP
Position AD conversion port, but because it can only receive electrode signal, it is therefore desirable to modulate circuit is designed by bipolar signal
Unipolar signal is transformed to, as shown in Figure 2.
Input voltage signal is converted to mA level current signals through resistance RA1 in Fig. 2, in voltage transformer (5mA:It is 5mA) secondary
The sampled resistance RA2 in side is converted to low-voltage analog signal.In modulate circuit, disturbed for suppression common mode, voltage transformer output
Post-amplifier is output to using differential fashion, transformed to through it within the scope of a/d converter allows.Now first order Ua1
Export and be with the relation of input voltage:
2.2 multi-point communication interfaces:
In view of the requirement of multiple spot quality of power supply collection, the collection of each point quality of power supply should be uploaded to by multi computer communication system
Host computer.The present invention devises RS485 interface circuits, can complete the remote information gathering of multiple monitoring terminals, such as Fig. 3 institutes
Show.
For upper machine communication by USB connection computers, FT232R can be converted to USB Transistor-Transistor Logic level, then be converted to through SP481
RS485 level connects for multiple slave computers.Wherein FT232R has a UART controller of internal programmable, baud rate from
18bps to 3Mbps is adjustable.CBUS3 with the CBUS4 pin configuration of programmable I/O is sent into SP481 data in this circuit
(TXDEN#) pin is enabled with receiving (PWREN#).CBUS0 and CBUS1 is then configured to data transmit-receive state end, external LED to
Indicate data reiving/transmitting state.
3rd, Software for Design
3.1 power quality parameters calculate
Power quality index in electric substation mainly includes each secondary major harmonic content in voltage and current, the balance of voltage
Degree, current balance type degree, power factor, phase relation etc..Wherein the most key is to calculate each harmonic content.
The present invention uses fft algorithm, calculates fundamental wave and less than 21 times major harmonic contents.Being calculated in view of quick FFT will
Ask and complete calculating complete cycle is carried out to signal, in order to lift the real-time of its calculating, reduce discrete FFT amounts of calculation, using passing
Return discrete fft algorithm.The core of the algorithm is to be calculated every time using last samples value.
A cycle is T, and angular frequency is ω periodic signal X (t), if carrying out discrete sampling, each periodic sampling to it
Count as N, sampling period τ, then periodic signal is represented by:
Storage of the sample sequence of periodic signal sampling in internal memory is as shown in the sample sequence figure of Fig. 8 periodic signals.
In a cycle calculating process, in above-mentioned calculating process since fixed starting point m=0, then to N-1 thereafter
Data simultaneously participate in computing, therefore slightly poor for the real-time of Instantaneous Harmonic analysis.If N number of sampling before known present sample i
Value, then:
Recurrence is carried out to it, the characteristic in binding signal cycle can obtain:
From above formula, FFT need to be only calculated current sampling point without N number of sampled point one when calculating harmonic content
Rise and calculate, each sampling period carries out data renewal according to sampled value present position, so as to reduce FFT amounts of calculation.
3.2 synchronized signal acquisitions
The collection of synchronized signal is the basis of power quality analysis, obtains electricity by three-phase software phlase locking principle herein
Net phase information.According to the principle of coordinate transform, three-phase voltage resultant vector usSize it is constant when, under synchronous rotating frame
UsQ axis components usqD axles and line voltage u can be reflectedsPhase relation.Work as usqWhen=0, line voltage usWith d axles
Same phase.By controlling usq=0 can realize both same-phases.By zero and usqAfter making the difference, ω is obtained through pi regulatorerr, with
Reference frequency ωNAfter comparing, by integration, pll phase angle θ is obtained.Its realization principle is as shown in Figure 4.
3.3MODBUS software protocol
Hardware of the present invention establishes master-slave mode multi computer communication system using RS485 networks, calls slave by main frame, slave should
The mode of answering is communicated.For the ease of being communicated with configuration softwares such as power controls, each module of slave computer uses MODBUS RTU
Communications protocol.The form arranged in communications protocol is as follows:
The MODBUS RTU communications protocol forms of table 1
。
MODBUS protocol definitions master-slave equipment recognition methods and defined message format.In view of the quality of power supply of calculating
Parameters precision, data typically use 2 bytes, and the initial address of each power quality parameter is specified in communications protocol.To prevent
Communication error, is verified using CRC16.
3.4 multiple spots detect and harmonic source location method
The first purpose of Power Quality Detection is to position harmonic source and division harmonic contributions.The present invention is based on harmonic wave
Power flow direction determines harmonic source orientation.Illustrate by taking Fig. 5 as an example.
Black patch is Power Quality Detection unit PQU in Fig. 5, and its harmonic source can be divided into forward and backward;Then Fig. 5 is then (b)
Middle Zs is certain PQU forward direction (mains side) equiva lent impedance, and Zc is its backward (user side) equiva lent impedance;Therefore system is humorous in Fig. 5 (c)
Wave impedance Z=Zs+Zc=jX, X are total harmonic wave reactance;Then harmonic power backward PQU in Fig. 5 (c) is:
P=UsIcos θ=UsUcsinδ/X (5);
Wherein θ is UsLeading current I phase, δ are that system side surveys harmonic source phase difference with user.When positive and negative values occurs in P
When, illustrate harmonic wave from not homonymy.
After determining harmonic direction, then it can be compared again by the numerical values recited of harmonic content in the multiple spot quality of power supply, enter one
Step determines the direction of each harmonic source.Still by taking Fig. 5 (a) as an example, 1. locate harmonic power positive and negative values by calculating PQU first, determine humorous
Wave source direction;If 2. harmonic source is defined as backward, then locates the reckoning of harmonic power progress next step by calculated for subsequent PQU, directly
To one-level PQU to the end.Then further more each PQU harmonic content how much, determine the main distribution of each harmonic.
The harmonic source location method flow diagram such as Fig. 6 calculated based on harmonic power.
With reference to result verification, the invention will be further described.
1 synchronization signal detection result
Fig. 7 is the result that the present apparatus calculates synchronized signal.Wherein UsaFor power network A phase voltages, ω is phase angle, UaFor
The power network A item fundamental signals being calculated according to ω.It can be seen that the accurate tracking to grid phase can be realized,
2nd, host computer configuration monitoring software
In order to monitor the quality of power supply information of each key node of transformer station in real time in host computer, the present invention establishes three
Diode phase does not control direct current experiment porch, particular harmonic pollution is made, for verifying monitoring effect.
Each main power quality parameter measured by the present apparatus, can be by setup parameter threshold value, to the ginseng of over range
Number carries out police instruction, and by the analysis to multinode parameter, main pollution sources of electrical energy quality effectively can also be positioned.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all essences in the present invention
All any modification, equivalent and improvement made within refreshing and principle etc., should be included in the scope of the protection.
Claims (5)
- A kind of 1. transformer station's multiple spot electric energy quality monitoring method, it is characterised in that transformer station's multiple spot electric energy quality monitoring side Method is detected by voltage and current and modulate circuit, and three-phase voltage and current signal are completed by DSP itself AD conversion port Collection, handled through internal algorithm, obtain each secondary voltage and current harmonic data, and analysis voltage, current-symmetrical degree, power because Element, the power quality parameter of total harmonic distortion;Quality of power supply result of calculation is continuously written into designated memory cell, then passed through MODBUS rtu protocols are sent to host computer analyzing and processing.
- 2. transformer station's multiple spot electric energy quality monitoring method as claimed in claim 1, it is characterised in that transformer station's multiple spot electricity Energy quality monitoring method specifically includes:Using DSP28335 as control core, by voltage and current modulate circuit, by three-phase voltage and current signal pick-up into symbol Close the low voltage single-pole DC form of DSP AD port levels requirement;By the arithmetic programming inside DSP AD conversion port, according to the three-phase voltage current numerical value of collection, with defined week Phase, calculate less than 25 times each harmonic contents of three-phase voltage and electric current, calculate three-phase voltage and current balance type degree, power because Number, and be stored in by defined data format in internal storage;MODBUS RTU communications protocol is followed, the multi computer communication of master-slave mode is completed using main frame calling slave mode;Host computer writes operation and control interface using ForceControl configuration software, carries out the extraction of power quality parameter, quantifies, identity transformation;Upper computer software algorithm is write, power quality parameter alarm threshold value is adjusted, to the exceeded parameter of threshold value in power quality parameter Carry out color, audible alarm prompting;During multimetering, according to power quality parameter numerical values recited, the directional spreding of prediction power quality problem potential pollution source.
- A kind of 3. transformer station's multiple spot electric energy quality monitoring dress of transformer station's multiple spot electric energy quality monitoring method as claimed in claim 1 Put, it is characterised in that transformer station's multiple spot equipment for monitoring power quality includes:DSP28335 controllers, for transformer station's multiple spot electric energy quality monitoring and control operation program;Modulate circuit, high-voltage great-current analog signal is first converted into low pressure low current AC signal, then turned through a/d conversion device Digital quantity is turned to be calculated;12 AD conversion ports are carried using DSP;Multi-point communication interface, for completing the remote information gathering of multiple monitoring terminals;Power quality parameter computing module, for calculating each harmonic content in voltage and current;Synchronized signal acquisition module, grid phase information is obtained by three-phase software phlase locking principle;According to coordinate transform Principle, three-phase voltage resultant vector usSize it is constant when, the u under synchronous rotating framesQ axis components usqReflect d axles With line voltage usPhase relation;Work as usqWhen=0, line voltage usWith the same phase of d axles;By controlling usq=0 is used to realize two The same-phase of person;By zero and usqAfter making the difference, ω is obtained through pi regulatorerr, with reference frequency ωNAfter comparing, by integration, obtain To pll phase angle θ;MODBUS software protocol modules, master-slave mode multi computer communication system is established using RS485 networks, slave is called by main frame, Slave response mode is communicated;Multiple spot detects and harmonic source location module, for positioning harmonic source and division harmonic contributions;And based on harmonic power tide Stream direction determines harmonic source orientation.
- 4. a kind of power quality parameter computational methods of transformer station's multiple spot equipment for monitoring power quality as claimed in claim 3, its It is characterised by, the power quality parameter computational methods use the discrete fft algorithm of recurrence, including:A cycle is T, and angular frequency is ω periodic signal X (t), if carrying out discrete sampling, each periodic sampling points are N, Sampling period is τ, then periodic signal is expressed as:<mrow> <mtable> <mtr> <mtd> <mrow> <msub> <mi>x</mi> <mi>n</mi> </msub> <mrow> <mo>(</mo> <mi>k</mi> <mi>&tau;</mi> <mo>)</mo> </mrow> <mo>=</mo> <msub> <mi>A</mi> <mi>n</mi> </msub> <mi>cos</mi> <mrow> <mo>(</mo> <mi>n</mi> <mi>&omega;</mi> <mi>k</mi> <mi>&tau;</mi> <mo>)</mo> </mrow> <mo>+</mo> <msub> <mi>B</mi> <mi>n</mi> </msub> <mi>sin</mi> <mrow> <mo>(</mo> <mi>n</mi> <mi>&omega;</mi> <mi>k</mi> <mi>&tau;</mi> <mo>)</mo> </mrow> </mrow> </mtd> </mtr> <mtr> <mtd> <mrow> <msub> <mi>A</mi> <mi>n</mi> </msub> <mo>=</mo> <mfrac> <mn>2</mn> <mi>N</mi> </mfrac> <munderover> <mi>&Sigma;</mi> <mrow> <mi>m</mi> <mo>=</mo> <mn>0</mn> </mrow> <mrow> <mi>N</mi> <mo>-</mo> <mn>1</mn> </mrow> </munderover> <mi>X</mi> <mrow> <mo>(</mo> <mi>m</mi> <mi>&tau;</mi> <mo>)</mo> </mrow> <mi>cos</mi> <mrow> <mo>(</mo> <mi>n</mi> <mi>&omega;</mi> <mi>m</mi> <mi>&tau;</mi> <mo>)</mo> </mrow> <mo>,</mo> </mrow> </mtd> </mtr> <mtr> <mtd> <mrow> <msub> <mi>B</mi> <mi>n</mi> </msub> <mo>=</mo> <mfrac> <mn>2</mn> <mi>N</mi> </mfrac> <munderover> <mi>&Sigma;</mi> <mrow> <mi>m</mi> <mo>=</mo> <mn>0</mn> </mrow> <mrow> <mi>N</mi> <mo>-</mo> <mn>1</mn> </mrow> </munderover> <mi>X</mi> <mrow> <mo>(</mo> <mi>m</mi> <mi>&tau;</mi> <mo>)</mo> </mrow> <mi>sin</mi> <mrow> <mo>(</mo> <mi>n</mi> <mi>&omega;</mi> <mi>m</mi> <mi>&tau;</mi> <mo>)</mo> </mrow> </mrow> </mtd> </mtr> </mtable> <mo>;</mo> </mrow>N is the multiple proportion of the signal and fundamental signal decomposed in formula, and An and Bn are amplitude of the periodic signal in n times of fundamental frequency;M is Sampled point sequence number, k are any one in N number of sampled point, and x (k τ) is the numerical value on k-th of sampled point;In a cycle calculating process, since fixed starting point m=0, then computing is simultaneously participated in N-1 data thereafter; If N number of sampled value before known present sample i, sampling period are then expressed as:<mrow> <mtable> <mtr> <mtd> <mrow> <msub> <mi>A</mi> <mi>n</mi> </msub> <mrow> <mo>(</mo> <mi>i</mi> <mo>)</mo> </mrow> <mo>=</mo> <mfrac> <mn>2</mn> <mi>N</mi> </mfrac> <munderover> <mi>&Sigma;</mi> <mrow> <mi>m</mi> <mo>=</mo> <mi>i</mi> <mo>-</mo> <mi>N</mi> <mo>+</mo> <mn>1</mn> </mrow> <mi>i</mi> </munderover> <mi>X</mi> <mrow> <mo>(</mo> <mi>m</mi> <mi>&tau;</mi> <mo>)</mo> </mrow> <mi>cos</mi> <mrow> <mo>(</mo> <mi>n</mi> <mi>&omega;</mi> <mi>m</mi> <mi>&tau;</mi> <mo>)</mo> </mrow> <mo>,</mo> </mrow> </mtd> </mtr> <mtr> <mtd> <mrow> <msub> <mi>B</mi> <mi>n</mi> </msub> <mrow> <mo>(</mo> <mi>i</mi> <mo>)</mo> </mrow> <mo>=</mo> <mfrac> <mn>2</mn> <mi>N</mi> </mfrac> <munderover> <mi>&Sigma;</mi> <mrow> <mi>m</mi> <mo>=</mo> <mi>i</mi> <mo>-</mo> <mi>N</mi> <mo>+</mo> <mn>1</mn> </mrow> <mi>i</mi> </munderover> <mi>X</mi> <mrow> <mo>(</mo> <mi>m</mi> <mi>&tau;</mi> <mo>)</mo> </mrow> <mi>sin</mi> <mrow> <mo>(</mo> <mi>n</mi> <mi>&omega;</mi> <mi>m</mi> <mi>&tau;</mi> <mo>)</mo> </mrow> </mrow> </mtd> </mtr> </mtable> <mo>;</mo> </mrow>The initial data signal of N sampled value before m=i-N+1 is sampled point i in above formula, to there is N number of number between sampled point i According to;Recurrence is carried out, the characteristic in binding signal cycle obtains:<mrow> <mtable> <mtr> <mtd> <mrow> <msub> <mi>A</mi> <mi>n</mi> </msub> <mrow> <mo>(</mo> <mi>i</mi> <mo>)</mo> </mrow> <mo>=</mo> <msub> <mi>A</mi> <mi>n</mi> </msub> <mrow> <mo>(</mo> <mi>i</mi> <mo>-</mo> <mn>1</mn> <mo>)</mo> </mrow> <mo>+</mo> <mfrac> <mrow> <mn>2</mn> <mo>&lsqb;</mo> <mi>X</mi> <mrow> <mo>(</mo> <mi>i</mi> <mi>&tau;</mi> <mo>)</mo> </mrow> <mo>-</mo> <mi>X</mi> <mrow> <mo>(</mo> <mi>i</mi> <mo>-</mo> <mi>N</mi> <mo>)</mo> </mrow> <mi>&tau;</mi> <mo>&rsqb;</mo> <mi>cos</mi> <mrow> <mo>(</mo> <mi>n</mi> <mi>&omega;</mi> <mi>i</mi> <mi>&tau;</mi> <mo>)</mo> </mrow> </mrow> <mi>N</mi> </mfrac> </mrow> </mtd> </mtr> <mtr> <mtd> <mrow> <msub> <mi>B</mi> <mi>n</mi> </msub> <mrow> <mo>(</mo> <mi>i</mi> <mo>)</mo> </mrow> <mo>=</mo> <msub> <mi>B</mi> <mi>n</mi> </msub> <mrow> <mo>(</mo> <mi>i</mi> <mo>-</mo> <mn>1</mn> <mo>)</mo> </mrow> <mo>+</mo> <mfrac> <mrow> <mn>2</mn> <mo>&lsqb;</mo> <mi>X</mi> <mrow> <mo>(</mo> <mi>i</mi> <mi>&tau;</mi> <mo>)</mo> </mrow> <mo>-</mo> <mi>X</mi> <mrow> <mo>(</mo> <mi>i</mi> <mo>-</mo> <mi>N</mi> <mo>)</mo> </mrow> <mi>&tau;</mi> <mo>&rsqb;</mo> <mi>s</mi> <mi>i</mi> <mi>n</mi> <mrow> <mo>(</mo> <mi>n</mi> <mi>&omega;</mi> <mi>i</mi> <mi>&tau;</mi> <mo>)</mo> </mrow> </mrow> <mi>N</mi> </mfrac> </mrow> </mtd> </mtr> </mtable> <mo>;</mo> </mrow>If monitoring signals are periodic signal, if An (i) represents the result of spectrum analysis of this calculating, if having known last time frequency spectrum The result An (i-1) of analysis, with reference to this to periodic signal this sampled value X (i τ) and at it before a complete cycle Sampled value X [(i-N) τ], then substitute into carry out recurrence, after the formula that the characteristic in binding signal cycle obtains, obtain this frequency Compose analysis result An (i);This Bn (i) is obtained according to last time result of spectrum analysis.
- 5. multiple spot detection and the harmonic source location side of a kind of transformer station's multiple spot equipment for monitoring power quality as claimed in claim 3 Method, it is characterised in that the multiple spot detection includes with harmonic source location method:Power Quality Detection unit PQU harmonic source is divided into forward and backward;Zs is PQU forward direction equiva lent impedance, and Zc is backward Equiva lent impedance;Harmonic impedance Z=Zs+Zc=jX, X are total harmonic wave reactance;Then harmonic power backward PQU is:P=UsIcos θ=UsUcsinδ/X;Wherein θ is UsLeading current I phase, δ are system side and user-side harmonic source phase difference;It is humorous when positive and negative values occurs in P Ripple is from not homonymy.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201711277048.7A CN107884654A (en) | 2017-12-06 | 2017-12-06 | A kind of transformer station's multiple spot equipment for monitoring power quality and method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201711277048.7A CN107884654A (en) | 2017-12-06 | 2017-12-06 | A kind of transformer station's multiple spot equipment for monitoring power quality and method |
Publications (1)
Publication Number | Publication Date |
---|---|
CN107884654A true CN107884654A (en) | 2018-04-06 |
Family
ID=61773212
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201711277048.7A Pending CN107884654A (en) | 2017-12-06 | 2017-12-06 | A kind of transformer station's multiple spot equipment for monitoring power quality and method |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN107884654A (en) |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109239482A (en) * | 2018-07-27 | 2019-01-18 | 南京瑞贻电子科技有限公司 | A kind of oscillograph with log equipment electric energy quality monitoring |
CN110068740A (en) * | 2019-05-22 | 2019-07-30 | 大连民族大学 | A kind of more Electric Power Parameter Detections |
CN110658407A (en) * | 2019-10-12 | 2020-01-07 | 西安交通大学 | Metering device |
CN110850203A (en) * | 2019-11-04 | 2020-02-28 | 铜陵有色金属集团股份有限公司 | Systematic harmonic comparison detection method |
CN112083279A (en) * | 2020-08-26 | 2020-12-15 | 深圳供电局有限公司 | Electric power automatic distributed information acquisition system and method |
CN112203315A (en) * | 2020-09-30 | 2021-01-08 | 福建省亿坤通信股份有限公司 | Iron tower base station abnormity detection method and equipment |
CN112394248A (en) * | 2020-11-20 | 2021-02-23 | 南方电网数字电网研究院有限公司 | Power quality measurement device, system and method |
CN112506114A (en) * | 2020-12-29 | 2021-03-16 | 河南辉煌科技股份有限公司 | Railway signal external power network monitoring device based on DSP chip |
CN112763969A (en) * | 2020-12-30 | 2021-05-07 | 深圳供电局有限公司 | Device and method for detecting field harmonic electric energy metering error |
CN112924798A (en) * | 2021-02-08 | 2021-06-08 | 北京中电普华信息技术有限公司 | Power quality monitoring method and device and electronic equipment |
CN114756072A (en) * | 2022-04-26 | 2022-07-15 | 江苏微导纳米科技股份有限公司 | Electric energy management method and related device for pure resistance heating system |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102565574A (en) * | 2011-12-06 | 2012-07-11 | 中国人民解放军海军工程大学 | Ship electric energy quality monitoring system |
CN104330627A (en) * | 2014-10-24 | 2015-02-04 | 华中科技大学 | Automatic power grid resonance detection method based on active injection current |
CN104635114A (en) * | 2015-03-04 | 2015-05-20 | 江苏省电力公司常州供电公司 | Electric energy quality disturbance source positioning system and positioning method |
-
2017
- 2017-12-06 CN CN201711277048.7A patent/CN107884654A/en active Pending
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102565574A (en) * | 2011-12-06 | 2012-07-11 | 中国人民解放军海军工程大学 | Ship electric energy quality monitoring system |
CN104330627A (en) * | 2014-10-24 | 2015-02-04 | 华中科技大学 | Automatic power grid resonance detection method based on active injection current |
CN104635114A (en) * | 2015-03-04 | 2015-05-20 | 江苏省电力公司常州供电公司 | Electric energy quality disturbance source positioning system and positioning method |
Non-Patent Citations (1)
Title |
---|
刘聪;戴珂;张树全;康勇;: "RDFT算法在有源电力滤波器中的应用", 电力自动化设备, no. 07, pages 2 * |
Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109239482A (en) * | 2018-07-27 | 2019-01-18 | 南京瑞贻电子科技有限公司 | A kind of oscillograph with log equipment electric energy quality monitoring |
CN110068740A (en) * | 2019-05-22 | 2019-07-30 | 大连民族大学 | A kind of more Electric Power Parameter Detections |
CN110658407A (en) * | 2019-10-12 | 2020-01-07 | 西安交通大学 | Metering device |
CN110850203B (en) * | 2019-11-04 | 2021-09-24 | 铜陵有色金属集团股份有限公司 | Systematic harmonic comparison detection method |
CN110850203A (en) * | 2019-11-04 | 2020-02-28 | 铜陵有色金属集团股份有限公司 | Systematic harmonic comparison detection method |
CN112083279A (en) * | 2020-08-26 | 2020-12-15 | 深圳供电局有限公司 | Electric power automatic distributed information acquisition system and method |
CN112203315A (en) * | 2020-09-30 | 2021-01-08 | 福建省亿坤通信股份有限公司 | Iron tower base station abnormity detection method and equipment |
CN112394248A (en) * | 2020-11-20 | 2021-02-23 | 南方电网数字电网研究院有限公司 | Power quality measurement device, system and method |
CN112506114A (en) * | 2020-12-29 | 2021-03-16 | 河南辉煌科技股份有限公司 | Railway signal external power network monitoring device based on DSP chip |
CN112763969A (en) * | 2020-12-30 | 2021-05-07 | 深圳供电局有限公司 | Device and method for detecting field harmonic electric energy metering error |
CN112763969B (en) * | 2020-12-30 | 2023-08-15 | 深圳供电局有限公司 | Device and method for detecting field harmonic electric energy metering error |
CN112924798A (en) * | 2021-02-08 | 2021-06-08 | 北京中电普华信息技术有限公司 | Power quality monitoring method and device and electronic equipment |
CN112924798B (en) * | 2021-02-08 | 2022-11-08 | 北京中电普华信息技术有限公司 | Power quality monitoring method and device and electronic equipment |
CN114756072A (en) * | 2022-04-26 | 2022-07-15 | 江苏微导纳米科技股份有限公司 | Electric energy management method and related device for pure resistance heating system |
CN114756072B (en) * | 2022-04-26 | 2023-11-10 | 江苏微导纳米科技股份有限公司 | Electric energy management method and related device for pure resistance heating system |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN107884654A (en) | A kind of transformer station's multiple spot equipment for monitoring power quality and method | |
CN104237645B (en) | A kind of transformer station direct current system state of insulation on-line monitoring system and method | |
CN102331534B (en) | Power distribution terminal detecting system and method | |
CN202351422U (en) | Automatic detection device of electric energy metering device | |
CN107402332A (en) | A kind of Intelligent power distribution terminal multi-epitope automatic checkout system and its detection method | |
CN103885438B (en) | The Auto-Test System of a kind of transformer station measuring and controlling equipment and method | |
CN104300900A (en) | Photovoltaic plate dust detecting device | |
CN106483397B (en) | A kind of electric energy quality detection device and measurement method of high-precision high bandwidth | |
CN102879661A (en) | Method and system for detecting distribution network automatic terminal | |
CN105548948A (en) | Device and method for testing digitalization electric energy metering system | |
CN102749541A (en) | Energy conservation-based real-time bus and metering equipment state on-line monitoring system | |
CN112596018B (en) | High-frequency signal-based power consumer relative position identification device, method and equipment | |
CN205608171U (en) | Digital electric energy measurement system's testing arrangement | |
CN203324466U (en) | Verification system capable of verifying multiple electric-energy meters with different current specifications at the same time | |
CN107807563A (en) | A kind of distribution parameter monitoring control system and control method | |
CN114200372A (en) | Remote detection method, system and storage medium for metering device | |
CN110429713A (en) | A kind of collecting and copying device fault diagnosis system based on terminal | |
CN109613354A (en) | A kind of power quality wireless monitor system and its monitoring method | |
CN202059085U (en) | Modular intelligent power distribution system | |
CN107085186A (en) | A kind of UPS battery fault detection system of STM32 | |
CN201281730Y (en) | Electric network loop-closing electricity-switching detection device | |
CN107645387A (en) | A kind of Internet of Things faulty equipment detecting system | |
CN109490658A (en) | Distribution terminal automatic verification system | |
CN205246753U (en) | Equipment with ammeter function | |
CN115078803A (en) | Distributed radio parameter sampling system and method |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination |