CN110943543A - Monitoring system applied to data of high-voltage direct-current power transmission system - Google Patents
Monitoring system applied to data of high-voltage direct-current power transmission system Download PDFInfo
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Abstract
The invention belongs to the technical field of power systems, and particularly relates to a data monitoring system applied to a high-voltage direct-current power transmission system, which comprises a data monitoring and processing unit, N data acquisition units, a data local storage unit, a human-computer interaction unit and a data transmission unit; the data monitoring and processing unit is used for carrying out error detection on the data acquired by each data acquisition unit, removing error information and judging the running state of the system; the N data acquisition units are connected with the data monitoring and processing unit in a bidirectional mode and are used for acquiring the operation data of the high-voltage direct-current power transmission system converter station and the direct-current power transmission line in real time. The invention can monitor the running state of the converter station of the high-voltage direct-current transmission system in real time, has the functions of processing and detecting the obtained data, and specifically comprises the functions of performing data coordinate transformation processing, generating standardized running state information, removing error information, judging the running state of the system, performing fault alarm and the like.
Description
Technical Field
The invention relates to the technical field of power systems, in particular to a data monitoring system applied to a high-voltage direct-current power transmission system.
Background
Compared with an alternating current transmission mode, the high-voltage direct current transmission technology changes an electric energy transmission mode from a traditional three-phase alternating current transmission system to a positive and negative ground direct current transmission system. Dc transmission systems have many technical advantages not found in ac systems, including better system stability, lower losses and higher economic transmission capacity. The technology has huge application prospects in the aspects of remote power transmission, new energy grid connection, asynchronous system interconnection and the like, and has been generally and commercially applied to various main power systems in the world.
The core equipment of the high-voltage direct-current transmission system is a direct-current converter station system. The main function of the direct current converter station system is to realize the alternating current/direct current conversion of electric energy through power electronic components, and provide a flexible and controllable electric energy conversion interface for the interconnection of alternating current and direct current systems.
In recent years, a modularized multi-level technology is applied to a main circuit topological structure of a high-voltage direct-current transmission converter station and is commercially and practically applied, and the purpose of alternating current-direct current conversion of a high-voltage high-current system can be achieved by combining a large number of modularized power electronic half-bridge and full-bridge unit modules in series-parallel connection, so that the construction cost of the direct-current converter station is effectively reduced, but on the other hand, the number of modules needing to be monitored in the modularized high-level high-voltage direct-current converter station is increased in a geometric progression manner compared with the conventional flexible high-voltage direct-current converter station due to the application of a large number of modularized.
In order to ensure that the high-voltage direct-current transmission equipment can safely, stably and efficiently run, the running states of each equipment of a converter station and a direct-current transmission line need to be monitored in real time, a large amount of real-time data is collected to help to evaluate the running state of a system, equipment running fault alarm is carried out, and faults are relieved as quickly as possible to reduce social and economic losses; therefore, how to effectively monitor the operation state of the converter station of the modular multi-level high-voltage direct-current transmission system becomes an important technical guarantee for ensuring the safe, stable and reliable operation of the high-voltage direct-current transmission system; meanwhile, in consideration of the monitoring requirements of the conventional high-voltage direct-current transmission converter station and the conventional flexible high-voltage direct-current transmission converter station, the running state monitoring equipment capable of covering the technical schemes of the converter stations of the three conventional high-voltage direct-current transmission systems is urgently needed; meanwhile, in consideration of the planning requirement of a future hybrid high-voltage direct-current power transmission system, the monitoring equipment has the function of counting the operation historical data of the converter stations with different technical schemes and generating various operation indexes.
Therefore, the invention provides a monitoring system applied to high-voltage direct-current transmission system data, which can complete the functions of real-time monitoring, calculation conversion, storage transmission, display alarm and the like of the operation state of a converter station aiming at three typical technical schemes of a converter station of a conventional high-voltage direct-current transmission system (thyristor scheme), a converter station of a conventional flexible high-voltage direct-current transmission system (GTO/IGBT full-bridge technical scheme) and a converter station of a modular multilevel high-voltage direct-current transmission system (MMC modular technical scheme). By additionally arranging the equipment, the running condition of the high-voltage direct-current power transmission system can be monitored in real time, error data are eliminated, and real-time local backup of the monitoring data is performed by fault alarm.
Disclosure of Invention
Technical problem to be solved
Aiming at the defects of the prior art, the invention provides a data monitoring system applied to a high-voltage direct-current power transmission system, and solves the problems in the background technology.
(II) technical scheme
In order to achieve the purpose, the invention provides the following technical scheme: a monitoring system applied to data of a high-voltage direct-current power transmission system comprises a data monitoring and processing unit, N data acquisition units, a data local storage unit, a man-machine interaction unit and a data transmission unit; the data monitoring and processing unit is used for carrying out error detection on the data acquired by each data acquisition unit, removing error information and judging the running state of the system; the N data acquisition units are connected with the data monitoring and processing unit in a bidirectional mode and are used for acquiring the operation data of the high-voltage direct-current power transmission system converter station and the direct-current power transmission line in real time; the human-computer interaction unit is connected with the data monitoring and processing unit in a bidirectional way, is used for displaying a real-time running state and carrying out fault alarm, and is also used for inputting a control instruction; the data local storage unit is bidirectionally connected with the data monitoring and processing unit and is used for storing the operating data; the data transmission unit is connected with the data monitoring processing unit in a bidirectional mode and is used for transmitting the data generated by the data monitoring unit to an upper-level monitoring center.
As a preferred technical solution of the present invention, each of the data acquisition units is connected to the data monitoring and processing unit through a standard socket with a 90 Pin.
As a preferred technical solution of the present invention, the data monitoring and processing unit has 128 90Pin standard socket interfaces.
As a preferred technical scheme of the invention, the data monitoring unit comprises an FPGA module and a DSP module.
As a preferred technical solution of the present invention, the data acquisition unit includes an acquisition module and an a/D converter module.
As a preferred embodiment of the present invention, the model of the a/D converter module is an AD7864 chip.
As a preferred technical scheme of the invention, the data local storage unit comprises a Flash drive chip and a Flash memory card.
As a preferred technical solution of the present invention, the data transmission unit includes an ethernet interface and a gigabit ethernet chip.
(III) advantageous effects
Compared with the prior art, the invention provides a data monitoring system applied to a high-voltage direct-current power transmission system, which has the following beneficial effects:
1. the monitoring system applied to the high-voltage direct-current transmission system data can monitor the operation state of a converter station of the high-voltage direct-current transmission system in real time, has the functions of processing and detecting the obtained data, and specifically comprises the functions of performing data coordinate transformation processing, generating standardized operation state information, removing error information, judging the operation state of the system, performing fault alarm and the like.
2. The monitoring system applied to the data of the high-voltage direct-current power transmission system has the functions of locally storing the acquired operation information and transmitting the network, so that operation monitoring personnel of the high-voltage direct-current power transmission system can know the real-time and historical operation states of the converter station, and the monitoring system has important significance for ensuring the safe and stable operation of the high-voltage direct-current power transmission system. The historical operating data can be used for further planning a subsequent high-voltage direct-current power transmission system and providing a quantitative calculation basis.
Drawings
FIG. 1 is a schematic block diagram of the system of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Examples
Referring to fig. 1, the present invention provides the following technical solutions: a monitoring system applied to data of a high-voltage direct-current power transmission system comprises a data monitoring and processing unit, N data acquisition units, a data local storage unit, a human-computer interaction unit and a data transmission unit.
The data monitoring and processing unit is used for carrying out error detection on the data acquired by each data acquisition unit, removing error information and judging the running state of the system; the data monitoring unit comprises an FPGA module and a DSP module.
The N data acquisition units are connected with the data monitoring and processing unit in a bidirectional mode and are used for acquiring the operation data of the high-voltage direct-current power transmission system converter station and the direct-current power transmission line in real time; each data acquisition unit is connected with the data monitoring and processing unit through a standard socket with 90Pin pins, and the data monitoring and processing unit is provided with 128 standard socket interfaces with 90 Pin; the data acquisition unit comprises an acquisition module and an A/D converter module, wherein the acquisition module comprises 16 Hall voltage sensors and 16 Hall current sensors.
The human-computer interaction unit is bidirectionally connected with the data monitoring and processing unit, is used for displaying a real-time running state and carrying out fault alarm, and is also used for inputting a control instruction; the man-machine interaction unit comprises an LCD display and a key module.
The data local storage unit is bidirectionally connected with the data monitoring and processing unit and is used for storing the operating data; the data local storage unit comprises a Flash drive chip and a Flash memory card.
The data transmission unit is bidirectionally connected with the data monitoring processing unit and is used for transmitting the data generated by the data monitoring unit to the upper-level monitoring center; the data transmission unit comprises an Ethernet interface and a gigabit Ethernet chip.
In this embodiment, the working principle of the present invention is as follows:
(1) the data acquisition unit monitors the analog quantity of alternating current voltage and current through a voltage transformer and a current transformer, the direct current voltage and current signals are monitored through a Hall voltage sensor and a Hall current sensor, the direct current voltage and current are measured by utilizing Hall effect, and because the analog voltage signals output by the Hall voltage sensor have certain difference with the voltage range which can be identified by an A/D converter module, the analog voltage signals need to be adjusted by a signal conditioning circuit to ensure that the level of the signals input to the A/D converter circuit is matched with the measuring range of the A/D converter module, and the measuring resolution of an A/D conversion chip is utilized to the maximum extent, so the output currents of the Hall voltage sensor and the Hall current sensor are converted into analog voltage signals of 8-10V- +10V in total after passing through a processing circuit, the analog voltage signal completes the conversion from analog quantity to digital quantity through the A/D converter module, and is sent to the DSP module for processing through an address bus and a data bus;
① FPGA module controls all connected data acquisition units in turn to complete data acquisition task of HVDC convertor station system through data bus and address bus according to the highest operation frequency of data acquisition unit;
② the data converted by the data acquisition unit is sent to the DSP module through the data bus for data processing, after the processing is finished, the DSP module sends an interrupt request signal to the FPGA module through a connecting wire, then the FPGA module receives the processed data result sent by the DSP module through the data and address bus, and calculates the data validity by using a detection algorithm, when the data is abnormal, the data is judged to be caused by faults of sensors and the like or real faults of the monitored object, finally, the FPGA module stores the data into the Flash memory card through the serial control line, and the FPGA module has the function of controlling the data to be acquired in real time and written into the Flash memory card;
③ the DSP module calculates and processes the obtained operation data of the high voltage DC transmission system to give the processing results of the high voltage DC transmission system in normal, warning and fault states as the operation basis for the processing of the subsequent units;
④ when the DSP module judges that the system is in alarm and fault state, the man-machine interaction unit can give a flash alarm prompt to the fault module of the high voltage direct current transmission system with alarm and fault according to the alarm and fault code information sent by the DSP module, and prompt the operator to check and process;
(3) ① LCD display screen can display the current high voltage DC transmission system running state information (including the whole high voltage DC transmission station AC side outlet three-phase voltage and current value, active and reactive power instantaneous value and voltage and current harmonic component calculation result; DC side outlet voltage, current and active power instantaneous value; each power semiconductor switch device voltage and current instantaneous value and normal, alarm and fault state character information) and the alarm identification in abnormal running state to flash alarm;
② the button module is convenient for the staff to input the corresponding instruction rapidly and accurately, switch the display content of the LCD screen;
(4) the operation data is firstly stored in a memory in a DSP module in a data monitoring processing unit, when the accumulated data reaches a certain scale (for example, 8Mb), the operation data is stored in a Flash memory card at one time, the loss of the Flash memory card is reduced, and the preset threshold value of the accumulated storage scale (the 8Mb) can be changed through the input of a key module; in addition, when the storage space of the Flash memory card overflows, the initial storage data is sequentially rolled and covered;
(5) data in the operation process are stored through the data local storage unit and are transmitted to the superior monitoring center through the data transmission unit, so that operation monitoring personnel of the high-voltage direct-current power transmission system can know the real-time and historical operation states of the converter station, and the method has important significance for ensuring the safe and stable operation of the high-voltage direct-current power transmission system. The historical operating data can be used for further planning a subsequent high-voltage direct-current power transmission system and providing a quantitative calculation basis.
The method starts or stops storing real-time operation data in a high-voltage direct-current power transmission system into a Flash memory card according to an instruction received by a gigabit Ethernet chip, the counter is added with 1 when the system receives a group of data, the used capacity of the current Flash memory card can be calculated by multiplying the storage numerical value of the counter by the length of a single group of data packets, when the available storage capacity of the Flash memory card is exhausted, an instruction signal for erasing a single data packet stored earliest on the Flash memory card is sent, after the data is erased, the latest single group of data packet result is stored to the position, and the effective coverage of the latest data on the earliest data is completed.
The detection algorithm of the invention is as follows: the system of the invention collects the running state of the high-voltage direct-current transmission system at intervals of 1 second, and the running state information is as follows:
the method comprises the steps that continuous running time ttotal is operated by the high-voltage direct-current power transmission system;
the system enters a fault state counter nfail;
a system direct current transmission current value idc;
the system direct current voltage value vdc and the system alternating current input active power Pac and the like;
the system converter station operating efficiency value may be obtained by η ═ v _ dc × i _ dc/P _ ac;
the system direct current system power loss can be obtained from P _ dclos ═ i _ dc, then ^2 × R _ dc;
wherein R _ dc is the equivalent resistance of the direct current transmission line;
the system failure probability statistics may be obtained from P _ fail ═ n _ fail/t _ total;
the invention immediately starts to calculate the parameters after acquiring the running state of the converter station of the direct current transmission system each time, stores the calculation result into a local Flash memory card through a data and address bus system, and then periodically transmits the calculation result to a superior monitoring center through an Ethernet for backup.
Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (9)
1. A monitoring system applied to data of a high-voltage direct-current power transmission system is characterized in that: the system comprises a data monitoring and processing unit, N data acquisition units, a data local storage unit, a man-machine interaction unit and a data transmission unit; the data monitoring and processing unit is used for carrying out error detection on the data acquired by each data acquisition unit, removing error information and judging the running state of the system; the N data acquisition units are connected with the data monitoring and processing unit in a bidirectional mode and are used for acquiring the operation data of the high-voltage direct-current power transmission system converter station and the direct-current power transmission line in real time; the human-computer interaction unit is connected with the data monitoring and processing unit in a bidirectional way, is used for displaying a real-time running state and carrying out fault alarm, and is also used for inputting a control instruction; the data local storage unit is bidirectionally connected with the data monitoring and processing unit and is used for storing the operating data; the data transmission unit is connected with the data monitoring processing unit in a bidirectional mode and is used for transmitting the data generated by the data monitoring unit to an upper-level monitoring center.
2. The system according to claim 1, wherein the monitoring system is adapted to monitor data in the hvdc transmission system by: and each data acquisition unit is connected with the data monitoring and processing unit through a standard socket with a 90Pin Pin.
3. A monitoring system for hvdc transmission system data according to claim 2 wherein: the data monitoring and processing unit is provided with 128 90Pin standard socket interfaces.
4. The system according to claim 1, wherein the monitoring system is adapted to monitor data in the hvdc transmission system by: the data monitoring unit comprises an FPGA module and a DSP module.
5. The system according to claim 1, wherein the monitoring system is adapted to monitor data in the hvdc transmission system by: the data acquisition unit comprises an acquisition module and an A/D converter module, wherein the acquisition module comprises 16 Hall voltage sensors and 16 Hall current sensors.
6. A monitoring system for HVDC transmission system data according to claim 5, further comprising: the model of the A/D converter module is an AD7864 chip.
7. The system according to claim 1, wherein the monitoring system is adapted to monitor data in the hvdc transmission system by: the man-machine interaction unit comprises an LCD display and a key module.
8. The system according to claim 1, wherein the monitoring system is adapted to monitor data in the hvdc transmission system by: the data local storage unit comprises a Flash drive chip and a Flash memory card.
9. The system according to claim 1, wherein the monitoring system is adapted to monitor data in the hvdc transmission system by: the data transmission unit comprises an Ethernet interface and a gigabit Ethernet chip.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111463899A (en) * | 2020-04-07 | 2020-07-28 | 国家电网有限公司 | Data monitoring device and method for high-voltage direct-current power transmission system |
| CN111614079A (en) * | 2020-05-14 | 2020-09-01 | 国网四川省电力公司经济技术研究院 | Hybrid high-voltage direct-current power transmission system planning index calculation device and method |
| CN112883634A (en) * | 2021-01-18 | 2021-06-01 | 中国南方电网有限责任公司超高压输电公司广州局 | DC measurement system state prediction method and system based on multi-dimensional analysis |
| CN113098046A (en) * | 2021-04-09 | 2021-07-09 | 国网河北省电力有限公司沧州供电分公司 | Offshore shore power flexible direct current converter valve monitoring system |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110376433A (en) * | 2019-08-07 | 2019-10-25 | 国家电网有限公司 | Back-to-back DC power transmission engineering converter station energy-consumption monitoring device, system and method |
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- 2019-12-14 CN CN201911287603.3A patent/CN110943543A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110376433A (en) * | 2019-08-07 | 2019-10-25 | 国家电网有限公司 | Back-to-back DC power transmission engineering converter station energy-consumption monitoring device, system and method |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111463899A (en) * | 2020-04-07 | 2020-07-28 | 国家电网有限公司 | Data monitoring device and method for high-voltage direct-current power transmission system |
| CN111614079A (en) * | 2020-05-14 | 2020-09-01 | 国网四川省电力公司经济技术研究院 | Hybrid high-voltage direct-current power transmission system planning index calculation device and method |
| CN112883634A (en) * | 2021-01-18 | 2021-06-01 | 中国南方电网有限责任公司超高压输电公司广州局 | DC measurement system state prediction method and system based on multi-dimensional analysis |
| CN113098046A (en) * | 2021-04-09 | 2021-07-09 | 国网河北省电力有限公司沧州供电分公司 | Offshore shore power flexible direct current converter valve monitoring system |
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