CN201335877Y - Online monitoring and diagnosis device of circuit breaker based on DSP in medium voltage power network - Google Patents
Online monitoring and diagnosis device of circuit breaker based on DSP in medium voltage power network Download PDFInfo
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- CN201335877Y CN201335877Y CNU2008201576954U CN200820157695U CN201335877Y CN 201335877 Y CN201335877 Y CN 201335877Y CN U2008201576954 U CNU2008201576954 U CN U2008201576954U CN 200820157695 U CN200820157695 U CN 200820157695U CN 201335877 Y CN201335877 Y CN 201335877Y
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Abstract
The utility model relates to an online monitoring and diagnosis device of a circuit breaker based on DSP in the medium voltage power network, which comprises a central control processing unit, a power module, a measurement function module and an input/output function module; wherein the central control processing unit is connected with the measurement function module and the input/output function module respectively; and the power module is connected with the central control processing unit, the measurement function module and the input/output function module respectively. The online monitoring and diagnosis device of the circuit breaker based on DSP in the medium voltage power network can timely offer the early warning information for fault and change, timely offers correct protective measures, reduces the accidents and losses caused by fault to the minimum extent, provides guidance for circuit breaker overhauling, has simple structure and practicability, stable and reliable working performance and wider application range, and lays a solid foundation for the further development of the technology of the circuit breaker in the medium voltage power network.
Description
Technical field
The utility model relates to the medium voltage network monitoring technical field, and the particularly circuit-breaker status monitoring technique field in the medium voltage network is meant that specifically isolating switch in a kind of medium voltage network is based on on-line monitoring and the diagnostic device of DSP.
Background technology
In the modern production life, isolating switch is most important control and a protection equipment in the electric system, and the consequence that its fault is brought is very serious.It is impaired directly to endanger circuit, the equipment protected by isolating switch, electric quantity loss; Indirect hazard then causes user's large-area power-cuts, and influence is lived normally, production even social stability.Simultaneously, isolating switch especially the medium and high pressure isolating switch be again the equipment that quantity is many, the maintenance amount is big, expense is high.
In the present prior art, what isolating switch was mainly carried out is the prophylactic repair system, and itself blindness is big, and introduces new potential faults easily, reduces the reliability of equipment.Therefore, high-voltage circuit-breaker status being carried out on-line monitoring, for the maintenance of equipment provides according to being very important, also is simultaneously the developing direction of modern medium voltage breaker monitoring and diagnostic techniques.
The utility model content
The purpose of this utility model is to have overcome above-mentioned shortcoming of the prior art, provide a kind of can monitor in real time the duty of isolating switch in real time and diagnosis, simple and practical, stable and reliable working performance, the scope of application comparatively widely the isolating switch in the medium voltage network based on on-line monitoring and the diagnostic device of DSP.
In order to realize above-mentioned purpose, the isolating switch in the medium voltage network of the present utility model has following formation based on on-line monitoring and the diagnostic device of DSP:
Isolating switch in this medium voltage network is based on on-line monitoring and the diagnostic device of DSP, its principal feature is, described device comprises central controlled processing unit, power module, measurement function module and input/output function module, described central controlled processing unit all is connected with the input/output function module with described test function module respectively, and described power module all is connected with described central controlled processing unit, test function module and input/output function module respectively.
Isolating switch in this medium voltage network comprises time measuring unit, graphite spout measuring unit, stroke measurment unit and general-purpose simulation measurement amount unit based on the on-line monitoring of DSP and the test function module in the diagnostic device, and described time measuring unit, graphite spout measuring unit, stroke measurment unit and general-purpose simulation measurement amount unit all are connected with described central controlled processing unit.
Isolating switch in this medium voltage network comprises that based on the on-line monitoring of DSP and the input/output function module in the diagnostic device control output unit, outer input-output unit synchronously and keyboard show printer subsystem, and described control output unit, outer input-output unit synchronously show that with keyboard printer subsystem all is connected with described central controlled processing unit.
Isolating switch in this medium voltage network shows that based on on-line monitoring and the keyboard in the diagnostic device of DSP printer subsystem comprises keyboard unit, display unit and print unit, and described keyboard unit, display unit and print unit all are connected with described central controlled processing unit.
Isolating switch in this medium voltage network comprises power supply power supply unit and constant current source subsystem based on on-line monitoring and the power module in the diagnostic device of DSP, and described power supply power supply unit all is connected with described central controlled processing unit, test function module and input/output function module by described constant current source subsystem.
Isolating switch in this medium voltage network is the TMSLF2407 dsp chip based on on-line monitoring and the central controlled processing unit in the diagnostic device of DSP.
Adopted isolating switch in the medium voltage network of this utility model based on on-line monitoring and the diagnostic device of DSP, owing to wherein by sensor the relevant information of isolating switch action is analyzed in time according to the diagnostic mode of inside, preserve, form historical data, and the isolating switch of affiliated transformer station is carried out unified management by setting up database, automatically form the historical trend curve, be convenient to analyze the historical variations situation of isolating switch, in time give the early warning information that is out of order and changes, managerial personnel can in time provide correct preventive measure, drop to the accident and the loss of barrier initiation for some reason minimum, for checking and overhaul isolating switch, the operations staff provides guidance, simultaneously simple and practical, stable and reliable working performance, the scope of application are comparatively extensive, for further developing of the isolating switch technology in the medium voltage network established solid foundation.
Description of drawings
Fig. 1 is that isolating switch in the medium voltage network of the present utility model is based on the high-level schematic functional block diagram of on-line monitoring and the diagnostic device of DSP.
Embodiment
In order more to be expressly understood technology contents of the present utility model, describe in detail especially exemplified by following examples.
See also shown in Figure 1, isolating switch in this medium voltage network is based on on-line monitoring and the diagnostic device of DSP, isolating switch in this medium voltage network is based on on-line monitoring and the diagnostic device of DSP, comprising central controlled processing unit, power module, measurement function module and input/output function module, described central controlled processing unit all is connected with the input/output function module with described test function module respectively, and described power module all is connected with described central controlled processing unit, test function module and input/output function module respectively.
Wherein, this test function module comprises time measuring unit, graphite spout measuring unit, stroke measurment unit and general-purpose simulation measurement amount unit, and described time measuring unit, graphite spout measuring unit, stroke measurment unit and general-purpose simulation measurement amount unit all are connected with described central controlled processing unit; Described input/output function module comprises that control output unit, outer input-output unit synchronously and keyboard show printer subsystem, and described control output unit, outer input-output unit synchronously show that with keyboard printer subsystem all is connected with described central controlled processing unit; Described keyboard shows that printer subsystem comprises keyboard unit, display unit and print unit, and described keyboard unit, display unit and print unit all are connected with described central controlled processing unit; Described power module comprises power supply power supply unit and constant current source subsystem, and described power supply power supply unit all is connected with described central controlled processing unit, test function module and input/output function module by described constant current source subsystem.
Simultaneously, described central controlled processing unit is the TMSLF2407 dsp chip.
In the middle of reality was used, according to the needs of isolating switch on-line monitoring system, system was a core with the TMSLF2407 dsp chip, adopted modular design method, made each sub-function module independent, to maintain easily.This system hardware part mainly comprises: control output unit, time measuring unit, general-purpose simulation measuring unit, graphite spout measuring unit, central management control module, liquid crystal display, mini-printer, keypad, communication, inside and outside module such as synchronously.
Each main sub-module is composed as follows:
1, time measuring unit
The effect of time channel is to measure the response time that the isolating switch control command is sent the back isolating switch, comprises main fracture, the actuation time of switching-on resistance, the actuation time that also can measure the auxiliary contact of breaker control circuit simultaneously.
Principle of work is as follows:
Fracture is measured: add the current source of 1 30mA on the loop, just can obtain the change in voltage of fracture, by 2 voltage comparators (2V and 18V), just can obtain the state variation of main fracture and combined floodgate fracture respectively.
The voltage contact is measured: the voltage to control loop carries out dividing potential drop, drives the ground level of triode, makes the constant current source of 30mA obtain a voltage by 100 given Ω resistance, by voltage comparator, obtains its state variation.Owing to have only 2 voltage comparators, fracture and voltage contact can not be measured simultaneously, distinguish by software setting.
Decision condition is as follows
Main fracture: during combined floodgate, loop resistance is less than 50 Ω, and behind the electric current by 30mA, the voltage at fracture two ends can not surpass the voltage comparator of 1.5V.2V just can distinguish state variation, is lower than the 2V fracture and is in "on" position, is higher than the 2V fracture and is in gate-dividing state.
Switching-on resistance fracture: during combined floodgate, loop resistance is less than 500 Ω, and behind the electric current by 30mA, the voltage at fracture two ends can not surpass the voltage comparator of 1.5V.18V just can distinguish state variation, be lower than the 18V fracture and be in "on" position, be higher than the 18V fracture and be in gate-dividing state.Since main fracture and the parallel connection of combined floodgate fracture,, after then main fracture closed a floodgate, the voltage at fracture two ends can drag down, and therefore closing a floodgate, fracture closes earlier than main fracture or the state variation that could distinguish them is divided in the back.
The voltage contact: during combined floodgate, the voltage at contact two ends reduces to 0, and triode ends, voltage is constant current source output open circuit voltage, and voltage is 3V during separating brake, just can distinguish state variation with the voltage comparator of 2V, be lower than the 2V fracture and be in "on" position, be higher than the 2V fracture and be in gate-dividing state.
The system module design is as follows:
System design is 3 load modules, corresponding 3 phases.4 passages of each module, corresponding 4 ports, each passage has 3 input ports.The accuracy of measurement of actuation time reaches 0.1ms, will consider that simultaneously each measures passage all independently power supply with the first passage of each module velocity survey Time Calculation benchmark as corresponding phase, isolates mutually between the passage.
Input port protection design is as follows:
Each port is increased withstand voltage electric capacity over the ground, and the input end of voltage comparator adds transient suppressor.If add transient suppressor over the ground at port, just can not be by the insulation resistance test of port to casing.Port can each port of withstand voltage 10kV. normally opened contact by relay be linked into system, normally opened contact needs closed during measurement.
2, control output unit
Adopt electronic switch, closed in 3 minutes 1, totally 4 tunnel outputs, every road is maximum, and the withstand voltage 500V. of reaching is no more than 250V in order to guarantee output voltage by electric current 30A, and output contact is protected with transient suppressor.1 light insulating power supply and 1 hand switch are adopted in every road, and the control utmost point of electronic switch and the drive signal of CPU are isolated.The control output contact is directly received on the control loop of isolating switch during use, the breaking-closing operating of control isolating switch, can finish branch, close, close isolating switch-minute, divide-close, oco, and the single-pole reclosing of A, B, C, oco-close-various the operation cycle of grading, and can send various divide-shut brake orders in the time of setting neatly according to the delay time value of setting.
3, general-purpose simulation measurement amount unit
The major function of general-purpose simulation passage is the waveform of the relevant simulating signal when measuring the isolating switch action, comprises stroke (straight line, corner), speed, coil current, loop voltage etc., in order to analyze the mechanical property and the related data of isolating switch.General-purpose simulation measurement amount unit design is 3 analog channels, the three-phase when correspondence is measured, and each passage all possesses said function, measures independent mutually, isolation between the passage, possesses Anti-interference Design such as shielding.Can measure passive amount (resistance straight line, corner), electric current, voltage (external electric parameters transducer).Inner output reference 5V voltage is adopted in resistance measurement, by the tapped voltage of 5k Ω resistance measurement.Adopt 16 A/D, sampling rate can reach 500K/s, and the storage data time is less than 2s.
4, graphite spout measuring unit
Isolating switch for types such as 3AT, 3AQ, because one section graphite contact is arranged, ratio of gear when stroke sensor is measured is special, and general surveying instrument can't be measured actuation time and velocity characteristic, is because the special construction and the isolating switch tester test philosophy of graphite contact isolating switch cause.At first, the contact of this graphite contact isolating switch is not a simple metal, is made up of 2 parts, and its arc extinguishing partly is a semiconductor graphite composition.When isolating switch just divide, just fashionable, electric arc mainly extinguishes by graphite contact, to protect the metal part of dynamic and static contact.In combined floodgate or separating brake process, the contact resistance value of metal water conservancy diversion bridge and graphite contact is non-constant.Therefore, the characteristic of semiconductor of graphite causes measuring error.Secondly, testing tool principle of work difference, the normal circuit breaker tester, to isolating switch graphite fracture working voltage or current signal sampling, record be the isolating switch make-and-break signal.
Generally sample by light-coupled isolation.K1 represents the fracture of isolating switch, when K1 opens, is equivalent to the breaker open operation state, and U1 ends, and optocoupler is obstructed, computer sampling be high level; When K1 is closed, be equivalent to the breaker closing state, the U1 conducting, computer sampling be low level, computing machine can be judged the state of switch, thus record divides, closing time.But the circuit of this structure can only be tested on off operating mode, can't record to the dynamic process of graphite contact, because the contact resistance of static contact and moving contact changes in the isolating switch course of action.And for assembling is not good isolating switch, and the graphite part of three-phase contact is not simultaneously
In the contact, so the regular tap tester is only with the principle of surveying break-make, the same period that can't accurately test the graphite contact isolating switch.The method that system adopts is to add constant current excitation to fracture, analyzes its associated arguments by the voltage transformation waveform at record isolating switch fracture two ends.In the breaker closing process, after fracture voltage was less than certain value, system thought that just the moving contact of isolating switch really touches the main contact part of static contact fully; During separating brake, after fracture resistance was greater than certain value, metal separating brake point was just thought by system.Because the metal of moving contact and static contact partly can reliably contact, be very reliable method the duration of contact of working voltage method test contact.
Be designed to 3 tunnel controlled 10A constant current source outputs according to above principle graphite spout measuring unit, each constant current source is independent mutually, isolation, and possesses the reverse protection ability, and the voltage of output is 0.5～1.0V.But 3 tunnel analog channel recording voltage waveforms, this analog channel possesses stronger antijamming capability, and the measuring voltage scope has 1V shelves and 2 ranges of 10V shelves optional, and system can be according to the change in voltage of fracture, automatically differentiate metal contact, calculate and close, divide time point.
5, central controlled processing unit
Central authorities' controlled processing unit is the core cell of whole device, and it is finished analog to digital conversion and gathers simulation and switching value in real time, output control action etc.CPU adopts dsp chip TMSLF2407 processor, adopts the 3.3V power voltage supply, has reduced the power consumption of controller, the execution speed of 40MIPS, the program storage of 32K byte FLASH, the RAM of 1.5K byte, the single port RAM of the dual port RAM of 544 words and 2K byte.Have the PWM passage, capturing unit is arranged, A/D converter, 4 level production line technology and 16 special hardware multipliers have very high processing speed, are fit to handle the real-time task of macrooperation amount.System resource in a large number that TMS320LF2407 is inner integrated can reduce cost of development.Central authorities' controlled processing unit is designed to possess self-checking function, can provide operation indication, the warning that makes mistakes, and supports outer synchronous operation and power down protection.Also have data communication function in addition, can carry out real-time Communication for Power by the RS-232 communication interface, the real time data that slave computer is collected is sent to processing, demonstration, diagnosis and the preservation that host computer carries out data.The while slave computer also can receive the order of host computer in real time and finish various test operations.
The overall characteristic on-line monitoring that can independently finish SF6 isolating switch, vacuum circuit breaker, graphite spout isolating switch etc. based on isolating switch on-line monitoring and the diagnostic system of DSP, analyze functions such as data, printout.For ease of isolating switch is carried out unified management, inquire about the historical situation of each isolating switch, for the monitoring and maintenance guidance is provided, the process flow diagram of method of the present utility model is as shown in Figure 1.
Software adopts Visual C++ and data management system SQL SERVER 2000 to write, and data communication interface is the RS-232 serial ports.Its major function is to receive the on-site signal of being sent here by serial ports by DSP, shows measured parameter and waveform, and can or set numerical value by keyboard inquiry.Host computer can also be realized the Long-distance Control of isolating switch by RS-232 in addition, the order that main frame such as can send branch, close can send, and the data that can in time main frame be collected are sent to PC and handle, show, analyze, store and print.The motion of switch can be sub-divided into μ m level, depict time response, velocity characteristic, the stroke characteristic of switch motion.Alleviate tester's workload, improved the reliability and the life-span of instrument.
Adopted isolating switch in the above-mentioned medium voltage network based on on-line monitoring and the diagnostic device of DSP, owing to wherein by sensor the relevant information of isolating switch action is analyzed in time according to the diagnostic mode of inside, preserve, form historical data, and the isolating switch of affiliated transformer station is carried out unified management by setting up database, automatically form the historical trend curve, be convenient to analyze the historical variations situation of isolating switch, in time give the early warning information that is out of order and changes, managerial personnel can in time provide correct preventive measure, drop to the accident and the loss of barrier initiation for some reason minimum, for checking and overhaul isolating switch, the operations staff provides guidance, simultaneously convenient to use, stable and reliable working performance, the scope of application are comparatively extensive, for further developing of the isolating switch technology in the medium voltage network established solid foundation.
In this instructions, the utility model is described with reference to its certain embodiments.But still can make various modifications and conversion obviously and not deviate from spirit and scope of the present utility model.Therefore instructions and accompanying drawing are regarded in an illustrative, rather than a restrictive.
Claims (6)
1, the isolating switch in a kind of medium voltage network is based on on-line monitoring and the diagnostic device of DSP, it is characterized in that, described device comprises central controlled processing unit, power module, measurement function module and input/output function module, described central controlled processing unit all is connected with the input/output function module with described test function module respectively, and described power module all is connected with described central controlled processing unit, test function module and input/output function module respectively.
2, the isolating switch in the medium voltage network according to claim 1 is based on on-line monitoring and the diagnostic device of DSP, it is characterized in that, described test function module comprises time measuring unit, graphite spout measuring unit, stroke measurment unit and general-purpose simulation measurement amount unit, and described time measuring unit, graphite spout measuring unit, stroke measurment unit and general-purpose simulation measurement amount unit all are connected with described central controlled processing unit.
3, the isolating switch in the medium voltage network according to claim 1 is based on on-line monitoring and the diagnostic device of DSP, it is characterized in that, described input/output function module comprises that control output unit, outer input-output unit synchronously and keyboard show printer subsystem, and described control output unit, outer input-output unit synchronously show that with keyboard printer subsystem all is connected with described central controlled processing unit.
4, the isolating switch in the medium voltage network according to claim 3 is based on on-line monitoring and the diagnostic device of DSP, it is characterized in that, described keyboard shows that printer subsystem comprises keyboard unit, display unit and print unit, and described keyboard unit, display unit and print unit all are connected with described central controlled processing unit.
5, according to on-line monitoring and the diagnostic device of the isolating switch in each described medium voltage network in the claim 1 to 5 based on DSP, it is characterized in that, described power module comprises power supply power supply unit and constant current source subsystem, and described power supply power supply unit all is connected with described central controlled processing unit, test function module and input/output function module by described constant current source subsystem.
According to on-line monitoring and the diagnostic device of the isolating switch in each described medium voltage network in the claim 1 to 5, it is characterized in that 6, described central controlled processing unit is the TMSLF2407DSP chip based on DSP.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102323502A (en) * | 2011-08-03 | 2012-01-18 | 上海毅昊自动化有限公司 | The line closed loop test macro and the method for testing thereof that are used for relay protection |
| CN102879676A (en) * | 2012-09-24 | 2013-01-16 | 西安供电局 | Relay protection tester based on embedded system, and checking method for relay protection tester |
| CN102982711A (en) * | 2012-11-22 | 2013-03-20 | 郑州万特电气有限公司 | Training device of split-phase breaker spring operation mechanisms |
| CN103293471A (en) * | 2013-04-25 | 2013-09-11 | 上海电器科学研究所（集团）有限公司 | Device and method capable of intelligently detecting electric leakage switch in communicating mode |
| CN104849657A (en) * | 2015-05-05 | 2015-08-19 | 国家电网公司 | Remote intelligent test device for switching characteristics |
| CN106249142A (en) * | 2016-10-18 | 2016-12-21 | 国网江苏省电力公司电力科学研究院 | A kind of extra-high voltage switch intelligent device for measuring |
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2008
- 2008-12-23 CN CNU2008201576954U patent/CN201335877Y/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102323502A (en) * | 2011-08-03 | 2012-01-18 | 上海毅昊自动化有限公司 | The line closed loop test macro and the method for testing thereof that are used for relay protection |
| CN102879676A (en) * | 2012-09-24 | 2013-01-16 | 西安供电局 | Relay protection tester based on embedded system, and checking method for relay protection tester |
| CN102879676B (en) * | 2012-09-24 | 2015-09-30 | 西安供电局 | A kind of reaying protection test instrument based on embedded system and the method for inspection thereof |
| CN102982711A (en) * | 2012-11-22 | 2013-03-20 | 郑州万特电气有限公司 | Training device of split-phase breaker spring operation mechanisms |
| CN103293471A (en) * | 2013-04-25 | 2013-09-11 | 上海电器科学研究所（集团）有限公司 | Device and method capable of intelligently detecting electric leakage switch in communicating mode |
| CN104849657A (en) * | 2015-05-05 | 2015-08-19 | 国家电网公司 | Remote intelligent test device for switching characteristics |
| CN104849657B (en) * | 2015-05-05 | 2018-04-10 | 国家电网公司 | A kind of switching characteristic long-distance intelligent test device |
| CN106249142A (en) * | 2016-10-18 | 2016-12-21 | 国网江苏省电力公司电力科学研究院 | A kind of extra-high voltage switch intelligent device for measuring |
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