CN203385846U - Absolute time-delay detection apparatus of mutual inductor data acquisition system of intelligent substation - Google Patents
Absolute time-delay detection apparatus of mutual inductor data acquisition system of intelligent substation Download PDFInfo
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- CN203385846U CN203385846U CN201320528116.3U CN201320528116U CN203385846U CN 203385846 U CN203385846 U CN 203385846U CN 201320528116 U CN201320528116 U CN 201320528116U CN 203385846 U CN203385846 U CN 203385846U
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Abstract
The utility model provides an absolute time-delay detection apparatus of a mutual inductor data acquisition system of an intelligent substation. The apparatus comprises a three-phase programmable power supply, an electronic mutual inductor, a merging unit, a Hall sensor, and a control work station. According to the utility model, the three-phase power supply which is modulatable in output voltage waveform is employed to realize voltage output with coding information; the Hall sensor is employed to record a corresponding waveform coding time sequence; and at the same time, the control work station detects and records corresponding output signals of the electronic mutual inductor and merging unit to be detected, and compares the corresponding output signals with the waveform coding time sequence recorded by the Hall sensor, thereby obtaining the absolute time-delay of the mutual inductor data acquisition system. Based on a waveform modulation technology and by modulating and generating the waveform with the coding information, a signal starting point can be determined accurately; and not only can the whole cycle time-delay problem be accurately detected, but also the phase difference of current and voltage can be detected at the same time.
Description
Technical field
The utility model relates to electric power detection technique field, specifically the absolute time delay pick-up unit of a kind of intelligent substation mutual inductor data acquisition system (DAS).
Background technology
Electronic mutual inductor has that the transient state scope is large, volume is little, quality is light, output signal can directly be inputted the Microcomputer metering and the advantage such as protection equipment interface.The high-pressure side of electronic mutual inductor and low-pressure side are without electrical connection, greatly simplified insulation system, insulating property have been improved, that electronic current mutual inductor is compared the most significant advantage with the conventional current mutual inductor, in the process of construction of intelligent grid, electronic mutual inductor and merge cells, as the key equipment in intelligent substation, will progressively replace traditional electromagnetic transformer.
The electronic mutual inductor type mainly comprises: the electronic type voltage transformer of passive electronic mutual inductor, optical current mutual inductor, Luo-coil type electronic current mutual inductor, employing voltage divider principle, its common ultimate principle be all by actual electric current, voltage analog signal by multi-form conversion and data acquisition process, last output digit signals.The data acquisition system (DAS) adopted at intelligent substation at present mainly is comprised of analog quantity induction link, A/D conversion links, data processing links, wherein also comprise data transmission procedure, therefore certainly exist a time delay between actual analog signals and final this signal of digital output, export absolute time delay.Export the size of absolute time delay; can directly have influence on the normal operation of the devices such as electric system detection, metering, monitoring, relay protection; to cause malfunction or the tripping of protective relaying device when serious; cause generation and the expansion of power grid accident; therefore must the absolute time delay of data acquisition system (DAS) of electronic mutual inductor and merge cells formation be detected for intelligent substation, judged whether it meets the correlation technique code requirements such as metering and relay protection.
Intelligent substation mutual inductor data acquisition system (DAS) is output as digital quantity, can't carry out time test by classic methods such as oscillographs.Present common method of testing is: utilize standard voltage source and current source, after the sampling of standard potential transformer summation current transformer, then compare with tested merging unit of electronic transformer output signal the amount of delay that obtains system under test (SUT).Adopt the method to test and need to install in addition debugging interface additional, as standard mutual inductor and source of synchronising signal, the execute-in-place complexity, and the method do not consider the time delay of electronic mutual inductor sensing device and transmission, test result is not accurate enough; In addition when electric current, System of voltage acquisition time delay are the complete cycle ripple, due to the starting point that can't determine waveform, therefore usual way can't detect at present, to the phase differential of electric current and voltage, also can't detect.
The utility model content
For the deficiencies in the prior art, the utility model proposes the absolute time delay pick-up unit of a kind of intelligent substation mutual inductor data acquisition system (DAS), solve the absolute delay test result of prior art not accurate enough; When being the complete cycle ripple, electric current, System of voltage acquisition time delay can't detect; And the phase differential of electric current and the voltage problem that can't detect.
The absolute time delay pick-up unit of a kind of intelligent substation mutual inductor data acquisition system (DAS), comprise electronic mutual inductor, merge cells, optical fiber, the output terminal of electronic mutual inductor is connected with the input end of merge cells by optical fiber, it is characterized in that: also comprise the three-phase programmable power supply, Hall element and control workstation, the three-phase programmable power supply, Hall element, electronic mutual inductor connects successively, the control end of three-phase programmable power supply is connected with the control signal output terminal of controlling workstation, the output terminal of Hall element is connected with an input end controlling workstation, the output terminal of merge cells is connected with another input end of controlling workstation.
Absolute time delay pick-up unit as above, the three-phase programmable power supply comprises a three-phase isolation transformer and three inverter power unit that are connected with the output terminal of three-phase isolation transformer, A, B, C three-phase voltage are sent into respectively corresponding inverter power unit through three-phase isolation transformer, and described inverter power unit comprises not control rectifying circuit, buck chopper circuit, SPWM inverter circuit and voltage, the current filtering circuit connected successively.
The utility model by the programmable power power supply can produce be interrupted sine wave, square wave, etc. multiple different pulsewidth, amplitude, frequency controlled power signal as the input quantity of electronic mutual inductor, be analyzed in order to record time delay under unlike signal, thereby guaranteed the accuracy of measuring; Due to by modulation voltage, the current waveform of programmable power power generation band coded message, thereby effective reference position of record current voltage is exactly determined the absolute time delay of intelligent substation mutual inductor data acquisition system (DAS).
The accompanying drawing explanation
Fig. 1 is the structural representation of the absolute time delay pick-up unit of the utility model intelligent substation mutual inductor data acquisition system (DAS);
Fig. 2 controls the functional block diagram of workstation in the utility model pick-up unit;
Fig. 3 is the circuit block diagram of three-phase programmable power supply in the utility model pick-up unit;
Fig. 4 is the circuit theory diagrams of inverter power unit in the programmable power supply of three-phase shown in Fig. 2;
Fig. 5 is the schematic diagram of the coding sine wave of the utility model three-phase programmable power supply output;
Fig. 6 utilizes the utility model to carry out the method flow schematic diagram that the absolute time delay of intelligent substation mutual inductor data acquisition system (DAS) detects;
Fig. 7 is that the A/D sampled signal of the simulation output of the utility model Hall element contrasts schematic diagram with the waveform sequential of the digital signal of merge cells output.
In figure: 1-three-phase programmable power supply, 2-Hall element, 3-electronic mutual inductor, 4-control workstation, 5-merge cells, 6-optical fiber, 7-instruction waveform generation module, 8-collection of simulant signal module, 9-merge cells receiver module, 10-setting module, 11-data analysis module, 12-display module, 13-three-phase isolation transformer, 14-inverter power unit, 15-not control rectifying circuits, 16-buck chopper circuit, 17-SPWM inverter circuit, 18-voltage, current filtering circuit.
Embodiment
Below in conjunction with the accompanying drawing in the utility model, the technical scheme in the utility model is clearly and completely described.
Figure 1 shows that the structural representation of the absolute time delay pick-up unit of the utility model intelligent substation mutual inductor data acquisition system (DAS), described pick-up unit comprises three-phase programmable power supply 1, Hall element 2, electronic mutual inductor 3, controls workstation 4, merge cells 5 and optical fiber 6.Three-phase programmable power supply 1, Hall element 2, electronic mutual inductor 3 connect successively, the control end of three-phase programmable power supply 1 is connected with the control signal output terminal of controlling workstation 4, the output terminal of Hall element 2 is connected with an input end controlling workstation 4, the output terminal of electronic mutual inductor 3 is connected with the input end of merge cells 5 by optical fiber 6, and the output terminal of merge cells 5 is connected with another input end of controlling workstation 4.
Three-phase programmable power supply 1 obtains energy from electrical network, receives from the instruction of controlling workstation 4, and the voltage and current of waveform is specified in output.The simulating signal of the output of Hall element 2 is as the standard signal that detects time delay, an input end of input control workstation 4; The voltage and current signal that electronic mutual inductor 3 gathers after treatment, is sent to merge cells 5 by optical fiber 6.Another input end of controlling workstation 4 gathers the signal from merge cells 5, and itself and the described standard signal received are analyzed, and draws absolute time delay Δ t.
Referring to Fig. 2, described control workstation 4 comprises instruction waveform generation module 7, collection of simulant signal module 8, merge cells receiver module 9, setting module 10, data analysis module 11 and display module 12.
Described instruction waveform generation module 7, with the control end of three-phase programmable power supply 1, be connected, for sending the coded order signal, make three-phase programmable power supply 1 output specify the voltage and current of waveform modulation voltage and the modulated current signal of coded message (with), described coded order signal is transferred to the control end of three-phase programmable power supply 1 by the control signal output terminal of described control workstation 4;
Described collection of simulant signal module 8, for receiving the simulating signal transmitted from Hall element 2, and become digital signal by above-mentioned simulating signal through the A/D sample conversion;
Described merge cells receiver module 9, the digital signal transmitted for receiving merge cells 5;
Described setting module 10, for realizing the setting to whole sensed system parameter and function, pass through man-machine interface, setting comprises the coded order of three-phase programmable power supply, the selection of Frame passage to be measured, the setting of proving installation time delay ξ t, the setting parameter that delayed data shows and the current/voltage phase differential shows, and will reach three-phase programmable power supply control panel and data analysis module 11 under parameter information to realize corresponding function;
Described data analysis module 11, with collection of simulant signal module 8, with merge cells receiver module 9, be connected, for receiving from the digital signal through the A/D sampling of collection of simulant signal module 8 transmission and the digital signal of merge cells receiver module 9 transmission, comparative analysis after the digital signal transmitted with merge cells receiver module 9 after the digital signal of A/D sampling that collection of simulant signal module 8 is transmitted is carried out interpolation algorithm, draw absolute time delay Δ t, detailed process refers to hereinafter method of testing workflow;
Described data analysis module 11, also for being combined the voltage of unit 5 outputs, the data of electric current after closeization of interpolation algorithm are carried out perunit value, amplitude by the value of each data point of voltage divided by voltage, the value of each data point of electric current is divided by the amplitude of electric current, then with reference to the Waveform Matching method in step g, waveform after waveform after voltage data is initial by workstation clock t0 and current data workstation clock t1 are initial is complementary, the mistiming corresponding voltage of t0 and t1, the relative time delay amount of the data of electric current, can be converted into by the power frequency 50Hz cycle phase differential of electric current and voltage.
Described display module 12, be connected with described data analysis module 11, for showing in real time tables of data and the curve map of absolute time delay Δ t.
Referring to Fig. 3, three-phase programmable power supply 1 comprises a three-phase isolation transformer 13 and three inverter power unit 14 that are connected with the output terminal of three-phase isolation transformer 13.A, B, C three-phase voltage are sent into respectively corresponding inverter power unit 14 through three-phase isolation transformer 13, three-phase signal is carried out to the phase-splitting processing, an inverter power unit 14 often joins, 14 of inverter power unit adopt synchronous optical fiber to connect, the inner ac-dc-ac inverter circuit that adopts in inverter power unit 14, can realize the functions such as frequency modulation phase modulation amplitude modulation of signal by the ac-dc-ac inverter circuit, three-phase signal postpones 120 ° of phase places successively, produces the controlled pulsewidth voltage of three-phase, current signal.
Referring to Fig. 4, described inverter power unit 14 mainly comprises four parts: not control rectifying circuit 15, buck chopper circuit 16, SPWM inverter circuit 17, voltage, current filtering circuit 18.Civil power has been realized the conversion of AC-to DC through control rectifying circuit 15 not, adjusting to the controllable electric power output voltage generally has the direct pressure regulation of pair output AC voltage and Converting Unit input vertical compression is regulated to two kinds of methods, the method that the present embodiment adopts straightening to press, in buck chopper circuit 16 links, DC voltage is carried out to the step-down processing, circuit is after step-down is processed, through adopting the inverter circuit 17 of SPWM modulation system, the AC power waveform of output codified, alternating current is again through superpotential, current filtering circuit 18 generates and meets the controllable voltage of controlling the workstation instruction, current waveform (being the described voltage and current with coded message).
Referring to Fig. 5, the sinusoidal wave production process of encoding is as follows: at first, control workstation 4 and send coded order to three-phase programmable power supply 1 according to the sinusoidal wave form of required generation, concrete, adopt the SPWM modulation system, using the sine wave of required generation as the reference signal, with carrier wave ratio after, produce coded order, coded order essence is a series of coded pulses, the break-make of the IGBT of SPWM inverter circuit 17 in control chart 4, thus it is sinusoidal wave to produce coding.It is 50Hz for frequency that diagram produces sine wave, the sine wave that amplitude is 100V, and according to a cycle sine, a cycle 0, two cycle sines, 0, three cycle sine of 2 cycles, the mode of three the cycle 0...... gained of being encoded, the zero level of take realizes the uniqueness of waveform position is judged as sign.
Referring to Fig. 6, workflow comprises: configuration testing loop, system go out initialization, Site Detection, generation monitoring result etc.At first, access host computer (controlling workstation 4), connect circuit, after power turn-on, system is debugged, debug complete, merge cells receiver module 9, collection of simulant signal module 8, display module 12, the data analysis module 11 of controlling workstation 4 carried out to initialization, carry out the isoparametric setting of instruction waveform simultaneously.After initialization and setting complete, power turn-on, system completes the comparative analysis of the generation of controlled pulsewidth waveform, signal synchronous collection and waveform automatically, finally obtains in real time definitely delay data, generates the real time data table and shows by display screen.
Described method of testing workflow is as follows:
A. three-phase programmable power supply 1 requires the adjustable voltage of output amplitude, phase place and frequency, electric current (being the described modulation voltage with coded message and modulated current signal) according to what control workstation 4 steering orders;
B. detect the coding waveforms of three-phase programmable power supply 1 output after ovennodulation by Hall element 2, using the voltage signal of collection as voltage standard signal u0, the current signal gathered is as current standard signal i0, through the A/D sampling thief high-speed sampling in the collection of simulant signal module, be stored to and control workstation 4, the voltage signal of all collections, current signal are beaten markers by the workstation clock;
C. the analog quantity electric current of three-phase programmable power supply 1 output, voltage signal, by electronic mutual inductor 3, through the A/D conversion, are output as digital signal, and through optical fiber 6, data are delivered to merge cells (MU) 5;
E. control digital voltage, the current signal that workstation 4 transmits merge cells 5 and stored by the unified clock frequency, record voltage, the current standard signal through the A/D sampling that gather from Hall element 2 simultaneously;
F. 11 pairs of electronic mutual inductors of data analysis module 3 of controlling workstation 4 gather digital voltage, the current signal exported by merge cells 5 and carry out linearity or Lagrange's interpolation algorithm reduction processing by the unified clock frequency, by its interpolation for Hall element 2, gather through the sample data group of identical sampling rate of A/D, and press the common storage of workstation clock order with voltage, current standard signal data through the A/D sampling that Hall element 2 gathers, for the time delay of g step, calculate.；
G. the data through the A/D sampling that the data of merge cells 5 outputs of 11 pairs of treated mistakes of upper step of data analysis module and Hall element 2 gather contrast coupling, draw the voltage between the data of data through the A/D sampling that Hall element 2 gathers and merge cells 5, the current waveform corresponding relation, as shown in Figure 7, the data storing through the A/D sampling that Hall element 2 gathers is at internal memory A, the data storing of merge cells 5 is at internal memory B, by both data zero-times of workstation clock synchronous, can complete the coupling corresponding relation of both data by coding characteristic, it is Data Matching after data and bn after a0, the corresponding workstation clock of a0 t0, the corresponding workstation clock of bn t1, the mistiming of above-mentioned both the Data Matching points of comparative analysis can calculate the absolute time delay of both waveforms: i.e. Δ t=t1-t0-ξ t, Δ t is the absolute time delay of equipment under test, ξ t is the tester time delay, comprise the time delay of absolute time delay pick-up unit inner high speed A/D sampling, and hardware signal processing time delay, but be fixing measured value.Then two groups of Wave datas being given to the display module 12 of controlling workstation 4 is shown; The data receiver part of data analysis module 11 is simultaneously to analog output amount and MU digital quantity vanning (by data acquisition graftabl appointed area), according to controlling workstation unified clock frequency, store, realize synchronizeing of imitated output quantity and MU digital quantity by the workstation internal clocking, method is as described in f, do not rely on equipment under test to the time system.
Instruction waveform generation module 7 modulation generates the classes ripple of encoding as shown in Figure 5, to test waveform, is identified, and solves the error that poor integer time waveform brings.
H. set three-phase programmable power supply 1 output voltage by instruction waveform generation module 7, the synchronous power frequency test signal of electric current, through above-mentioned b to the f process, be combined the voltage of unit output, the data of electric current after closeization of interpolation algorithm are carried out perunit value, amplitude by the value of each data point of voltage divided by voltage, the value of each data point of electric current is divided by the amplitude of electric current, then with reference to the Waveform Matching method in g, waveform after waveform after voltage data is initial by workstation clock t0 and current data workstation clock t1 are initial is complementary, the mistiming corresponding voltage of t0 and t1, the relative time delay amount of the data of electric current, can be converted into by the power frequency 50Hz cycle phase differential of electric current and voltage,
I. complete test report, finish test job.
Claims (2)
1. the absolute time delay pick-up unit of intelligent substation mutual inductor data acquisition system (DAS), comprise electronic mutual inductor (3), merge cells (5), optical fiber (6), the output terminal of electronic mutual inductor (3) is connected with the input end of merge cells (5) by optical fiber (6), it is characterized in that: also comprise three-phase programmable power supply (1), Hall element (2) and control workstation (4), three-phase programmable power supply (1), Hall element (2), electronic mutual inductor (3) connects successively, the control end of three-phase programmable power supply (1) is connected with the control signal output terminal of controlling workstation (4), the output terminal of Hall element (2) is connected with an input end controlling workstation (4), the output terminal of merge cells (5) is connected with another input end of controlling workstation (4).
2. the absolute time delay pick-up unit of intelligent substation mutual inductor data acquisition system (DAS) according to claim 1, it is characterized in that: three-phase programmable power supply (1) comprises a three-phase isolation transformer (13) and three the inverter power unit (14) that are connected with the output terminal of three-phase isolation transformer (13), A, B, the C three-phase voltage is sent into respectively corresponding inverter power unit (14) through three-phase isolation transformer (13), described inverter power unit (14) comprises the not control rectifying circuit (15) connected successively, buck chopper circuit (16), SPWM inverter circuit (17) and voltage, current filtering circuit (18).
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103792419A (en) * | 2014-03-04 | 2014-05-14 | 济南大学 | Synchronous sampling method achieving hybrid access of analog quantity and digital quantity |
| CN104007346A (en) * | 2014-05-28 | 2014-08-27 | 广西电网公司电力科学研究院 | Analog quantity merging unit transient state delay test method based on frequency scanning |
| CN104330758A (en) * | 2014-09-02 | 2015-02-04 | 深圳市星龙科技股份有限公司 | Whole-cycle-wave-delay detection device and method of electronic mutual inductor |
| CN105319436A (en) * | 2014-06-12 | 2016-02-10 | 国网山西省电力公司电力科学研究院 | Smart station 3/2 wiring bus reactive power checking method based on traditional transformer |
| CN108196215A (en) * | 2018-01-04 | 2018-06-22 | 广东电网有限责任公司电力科学研究院 | A kind of DC electronic transformer delay time test method and device |
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- 2013-08-28 CN CN201320528116.3U patent/CN203385846U/en not_active Expired - Lifetime
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103792419A (en) * | 2014-03-04 | 2014-05-14 | 济南大学 | Synchronous sampling method achieving hybrid access of analog quantity and digital quantity |
| CN103792419B (en) * | 2014-03-04 | 2016-01-20 | 济南大学 | Realize analog quantity and mix the synchronous sampling method accessed with digital quantity |
| CN104007346A (en) * | 2014-05-28 | 2014-08-27 | 广西电网公司电力科学研究院 | Analog quantity merging unit transient state delay test method based on frequency scanning |
| CN104007346B (en) * | 2014-05-28 | 2017-02-22 | 广西电网公司电力科学研究院 | Analog quantity merging unit transient state delay test method based on frequency scanning |
| CN105319436A (en) * | 2014-06-12 | 2016-02-10 | 国网山西省电力公司电力科学研究院 | Smart station 3/2 wiring bus reactive power checking method based on traditional transformer |
| CN105319436B (en) * | 2014-06-12 | 2017-07-18 | 国网山西省电力公司电力科学研究院 | The wiring bus reactive power rate method of calibration of intelligent station 3/2 based on traditional transformer |
| CN104330758A (en) * | 2014-09-02 | 2015-02-04 | 深圳市星龙科技股份有限公司 | Whole-cycle-wave-delay detection device and method of electronic mutual inductor |
| CN104330758B (en) * | 2014-09-02 | 2017-07-04 | 深圳市星龙科技股份有限公司 | A kind of electronic mutual inductor complete cycle ripple time delay detection device and method |
| CN108196215A (en) * | 2018-01-04 | 2018-06-22 | 广东电网有限责任公司电力科学研究院 | A kind of DC electronic transformer delay time test method and device |
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