CN201278459Y

CN201278459Y - Digital transformer protection apparatus

Info

Publication number: CN201278459Y
Application number: CNU2008201360610U
Authority: CN
Inventors: （请求不公开姓名）
Original assignee: Shanxi Nanzi Jinneng Automation Complete Set Co Ltd
Current assignee: NANZI JINNENG AUTOMATION Co.,Ltd.; SHANXI NANZI JINNENG AUTOMATION Co.,Ltd.
Priority date: 2008-09-27
Filing date: 2008-09-27
Publication date: 2009-07-22
Anticipated expiration: 2018-09-27

Abstract

The utility model relates to a protection device of a digital transformer, which belongs to the technical field of power transformer protection. The utility model aims to provide a device which can modularize and standardize all functional units and integrate the functional units on a box body by inserters which are not interfered mutually, and can also display the whole work process so that the whole device has high level of sensitivity, precision and working reliability as well as convenient installation and maintenance, thereby being a protection device of a whole transformer, which is formed by matching a differential protector, a reserve protector and a body protector. The protection device of a digital transformer has a structure that the differential protector mainly comprises a singlechip, a DI opening-inserting unit, an AD sampling unit, a DO opening unit, a communication unit, a human-computer interface unit and a power circuit unit, wherein the singlechip is respectively connected with the DI opening-inserting unit, the AD sampling unit, the DO opening unit, the communication unit, the human-computer interface unit and the power circuit unit by leads. The protection device can be widely applied in various transformer substations.

Description

Digital transformer protector

Technical field

The utility model relates to a kind of digital transformer protector, and this device is protection and the monitoring integrated apparatus that aims at the power transformer of 35-22V electric pressure, belongs to the power trans-former protection technical field.

Background technology

Comprehensive automation of electric power system has been the direction of power network development; the development of microelectronic element makes protection and the monitoring possibility that combined together; can improve its reliability and operation and management level; but use microcomputer that many unfavorable factors are also arranged in transformer station; the for example interference of high-voltage electromagnetic field; strong vibration is arranged during the transformer substation switch operation; the deterioration of installation environment has proposed vibrationproof to Microcomputer Protection on the spot; wide temperature range; low-power consumption; anti-interference; high sensitivity; high accuracy; functional reliability; installation and maintenance conveniently wait higher requirement, and these difficult problems all are not resolved in existing microcomputer protecting device.

The utility model content

In order to overcome the problem that prior art exists; problem to be solved in the utility model is: a kind of digital transformer protector is provided; all modularization and standardization are integrated on the casing in the mode of plug-in unit with all functions unit; interference-free mutually between each plug-in unit; entire work process can show; make whole device highly sensitive, precision is high, functional reliability is high, installation and maintenance are convenient, is cooperated the complete protection equipment for transformer of forming by differential protection, backup protection, main body protection.

In order to address the above problem, the scheme that the utility model adopts is: digital transformer protector, mainly comprise: differential protection, backup protection equipment and main body protection device, described differential protection mainly comprises: single-chip microcomputer, DI opens into the unit, the AD sampling unit, DO leaves the unit, communication unit, human and machine interface unit, the power circuit unit, single-chip microcomputer leaves into the unit with DI respectively by lead, the AD sampling unit, DO leaves the unit, communication unit, human and machine interface unit links to each other with the power circuit unit, and DO leaves the unit and links to each other with the power circuit unit by lead;

The single-chip microcomputer of above-mentioned differential protection, DI leave and leave unit, communication unit, human and machine interface unit and power circuit unit into unit, AD sampling unit, DO to be modularization integrated, DI opens unit, AD sampling unit, DO and leaves unit, communication unit and power circuit unit all by on the integrated backboard that is fixed on casing of modularization, and human and machine interface unit is by on the integrated front panel that is fixed on casing of modularization;

The left side of front panel middle and upper part is provided with liquid crystal display screen, the right side of liquid crystal display screen is provided with indicator light, the below of liquid crystal display screen is provided with action button, the lower right side of action button is provided with serial line interface, and the below of action button is provided with debugging safe brace, ground connection branch/close handle and operational mode diverter switch from left to right;

Be disposed with interchange module, CPU module, communication interface module, signal and breaker tripping and closing outlet module, power supply module, non electrical quantity outlet plug-in unit and non electrical quantity plug-in unit from right-to-left on the backboard.

The single-chip microcomputer of differential protection is made up of CPU module and peripheral circuit.

The structure of backup protection equipment is identical with differential protection, just is disposed with reserve logic and tripping operation plug-in unit, back-up source module, reserve signal module, reserve breaker tripping and closing outlet module, reserve communication interface module on its reserve backboard from left to right, the reserve CPU module exchanges inputting modular unit with reserve.

The utility model digital transformer protector compared with prior art has following beneficial effect:

The all functions unit of this device all modularization and standardization is integrated on the casing in the mode of plug-in unit, have only inner 5V and the 24V electric pressure loop line that uses on the casing, strong and weak electricity separates fully, can significantly reduce the coupling of external electromagnetic interference in weak-feedback side of transmission line, strengthen the antijamming capability of this device, improved its reliability and fail safe.Make this device on functional configuration, have very strong flexibility, can change or increase part module, expand or change the function of this device according to user's request; This device is cooperated and is formed by differential protection, backup protection, main body protection.

Description of drawings

Below in conjunction with accompanying drawing the utility model digital transformer protector is described further:

Fig. 1 is the system block diagram of the utility model digital transformer protector;

Fig. 2 is the hardware configuration schematic diagram of differential protection 100 in the utility model digital transformer protector;

Fig. 3 is the structural representation of differential protection 100 dorsulums 12 shown in Figure 2;

Fig. 4 is the structural representation of reserve backboard 28 in the backup protection equipment 200 among Fig. 1.

Wherein, the 1-single-chip microcomputer; 2-DI opens into the unit; the 3-AD sampling unit; 4-DO leaves the unit; the 5-communication unit; the man-machine boundary of 6-and unit; 7-power circuit unit; the 8-transformer; the 9-relay; the 10-signal picker; the 11-casing; the 12-backboard; the 13-front panel; the 14-liquid crystal display screen; the 15-indicator light; 16-action button 16, the 17-serial line interface; 18-debugs safe brace; 19-ground connection branch/close handle; 20-operational mode diverter switch; 21-exchanges module; the 22-CPU module; 23-communication interface module; 24-signal and breaker tripping and closing outlet module; 25-power supply module; 26-non electrical quantity outlet plug-in unit; 27-non electrical quantity plug-in unit; 28-reserve backboard; 29-reserve logic and tripping operation plug-in unit; 30-back-up source module; 31-reserve signal module; 32-reserve breaker tripping and closing outlet module; 33-reserve communication interface module; 34-reserve CPU module; 35-reserve exchanges inputting modular unit; the 100-differential protection; the 200-backup protection equipment; 300-main body protection device.

Embodiment

As shown in Figure 1: digital transformer protector; mainly comprise: differential protection 100; backup protection equipment 200 and main body protection device 300; the differential protection dress back of the body 100 mainly comprises: single-chip microcomputer 1; DI opens into unit 2; AD sampling unit 3; DO leaves unit 4; communication unit 5; human and machine interface unit 6; power circuit unit 7; single-chip microcomputer 1 leaves into unit 2 with DI respectively by lead; AD sampling unit 3; DO leaves unit 4; communication unit 5; human and machine interface unit 6 links to each other with power circuit unit 7; DO leaves unit 4 and links to each other with power circuit unit 7 by lead; the signal picker 10 of AD sampling unit 3 is gathered the electric current and the voltage data of transformers 8, and DO leaves unit 4 and links to each other with relay 9 on the transformer 8.

After single-chip microcomputer 1 obtains the digital signal of sampling; carry out the amplitude information of digital filtering and algorithm computing acquisition analog quantity; respectively through the logic determines of protection software module, show to handle, links such as report storage, record ripple, after satisfying the protection operation condition, send orders such as tripping operation, signal to outlet loop.Because the space that single-chip microcomputer 1 inner nothing is deposited program, defence program is to leave among the flash memory FLASH, and single-chip microcomputer 1 comes the fetch program order by bus and carries out.Main program is a manager in software, is responsible for the module of difference in functionality is organized together.Initialization in the main program mainly is that whole system is that operate as normal is ready, and for the main transformer protection device, main program mainly comprises: CPU initialization and to the necessary parameter default settings.Main program entered operating state after initialization was finished, and showed on the liquid crystal display screen at first to judge whether relevant menu to carry out fixed value adjusting work, then changed the fixed value adjusting module if desired over to, otherwise continued to carry out downwards.Gathering switching value and detecting in the keyboard link, if detect the switching value displacement or a button is pressed, then send information and change message processing module over to and handle by main program, the result of information processing is sent to and shows that print module shows, prints, otherwise program continues to carry out signals collecting and computing module downwards.Whether needs move logic judgment module according to the relevant condition judgment with other of the calculated value of voltage power-less.After logic judgment module produces action command, whether move by the checkout gear exit relay, and the state that detects measured equipment judges whether action command obtains correct execution, if correct execution then change next time circulation over to, handle otherwise this abnormal information is sent to message processing module, again the result is given the demonstration output module.After the electrification reset, at first CPU and peripheral chip thereof are carried out initialization, next the state of a control of initialization simultaneously shows main menu, adopts inquiry mode to handle keyboard at last and communicates by letter with the A/D conversion and with intelligent object, obtains information.Communicate by letter with host computer and to adopt the interruption form, and interrupt levels is made as the highest.The input of switching value is taked to produce earlier to interrupt, the method for back inquiry.

AD sampling unit 3 realizes that multichannel exchanges the analog-to-digital conversion of analog signal, and provides real-time high-precision digital signal to single-chip microcomputer 1.Electric weight in the electric power system generally all is an analog quantity, and the realization of digital relay protection then is based on by microcomputer and digital quantity is calculated and judges.So,, must carry out series of preprocessing to simulation electric weight, thereby the digital quantity that obtains desired form offers the defencive function handling procedure from protected location equipment in order to realize the computer relaying protection.The analog signal that is input to protective relaying device by electric power system mainly is alternating voltage (or electric current) signal from PT (or CT).According to sampling thheorem: if measured signal frequency (or will keep in the signal high order harmonic component frequency) is f0, then sample frequency fk (sampling number of each second) must be greater than 2 times of fk, otherwise, just can not be reduced into original curve by the sampled value match ".Therefore, at the harmonic wave that occurs greater than the 1/2fk frequency, and these harmonic waves are again under the useless situation, are necessary that introducing sampler at signal installed in the past that an analog low pass pass filter equals frequency and the high order harmonic component that is higher than 1/2fk filters.Therefore analog signal at first is switched to the level that is complementary with microcomputer, by prune wherein radio-frequency component of mould filtering, keeps link with the continuous signal discretization by sampling then.Because often more than one of input signal becomes digital quantity so give A/D converter one by one by multiplexer.These digital quantities also should be arranged in memory sequentially to make things convenient for the function treatment program to take.In the circuit design of AD sampling unit 3, set up the low-pass filtering loop that the two-stage Resistor-Capacitor Unit constitutes, the analog quantity input signal is through the low-pass filtering loop, respectively signal is inserted the input of two multicircuit switch devices, the output signal of multicircuit switch is passed to the input circuit of AD conversion chip respectively, carry out analog-to-digital conversion, regularly read the result of AD conversion by CPU, be used as the original sampling data of each road analog quantity.

DI opens into unit 2 to from the opening into amount of external connector, after opening entry loop photoelectricity and isolating, to single-chip microcomputer 1 input, judges anti-interference process through software logic through tri-state gate circuit, obtains and opens into the amount signal.The 24V signal power source that external switch amount (idle contact) taking device provides, through the resistance current limliting, be input to the input of optical isolator, the output of optical isolator is taken inner 5V power supply, be linked into 8 road triple gate devices, read " 0 " or the one state of signal by CPU through bus, to differentiate the switching situation of external connector.Adopting optical isolator that the outside is opened into power supply and inner 5V power supply does not have direct electrical link, has effectively eliminated the influence of external electromagnetic interference to the CPU internal circuit, improved reliability.

DO leaves unit 4 and carries out the outlet action command that is sent by CPU, and through the input circuit of AND circuit to optical isolator, the output of optical isolator drives the actuating of relay through unilateral diode.The importation of optical isolator is the inner 5V power supply of CPU, and output is the 24V power supply, in order to drive the 24V relay.By optical isolator CPU internal circuit and relay drive circuit are isolated, effectively prevented electromagnetic interference, improved the reliability of hardware circuit.For guaranteeing the reliability of outlet loop, adopted multinomial locking measure.As adopt the open outlet of starting component positive supply, adopt hardware watchdog locking outlet etc.When single-chip microcomputer 1 sends the outlet order, must send the unlocking signal, drive starting relay simultaneously and can drive exit relay, send trip signal.

Differential protection 100 can accomplish that four sides are differential, complete star-like wiring of CT secondary support or conventional wiring; Biased differential protection, band CT breakage lock device; Secondary harmonic brake; The even-order harmonic braking; Differential fast tripping protection; Alarm of CT broken string and locking.

The structure of backup protection equipment 200 is identical with differential protection 100, is the plug-in unit difference of its reserve backboard 28, and it realizes overcurrent protection; The composite voltage overcurrent protection; The overcurrent protection of composite voltage direction; The zero sequence overcurrent protection; The zero sequence direction overcurrent protection; The overcurrent protection of residual voltage locking zero sequence; Gap protection; Non-whole phase protection; The overload alarm function; The locking voltage regulation function; Fan is pressed the current start function.

Main body protection device 100 is identical with existing equipment, can insert 12 road external switch amounts, and wherein tripping operation amount can reach 6, realizes the protection of this body weight; Load-carrying protection is arranged; The light protection of body; The light protection of carrying is arranged; The pressure release guard; The cooler error protection; Protection is jumped in the zero sequence choosing; The low protection of oil level; Temperature protection etc.

Fig. 2 and shown in Figure 3; the single-chip microcomputer 1 of above-mentioned differential protection 100, DI leave and leave unit 4, communication unit 5, human and machine interface unit 6 and power circuit unit 7 into unit 2, AD sampling unit 3, DO to be modularization integrated; DI opens unit 2, AD sampling unit 3, DO and leaves unit 4, communication unit 5 and power circuit unit 7 all by on the integrated backboard 12 that is fixed on casing 11 of modularization, and human and machine interface unit 6 is by on the integrated front panel 13 that is fixed on casing 11 of modularization.

The left side of front panel 13 middle and upper parts is provided with liquid crystal display screen 14, the right side of liquid crystal display screen 14 is provided with indicator light 15, the below of liquid crystal display screen 14 is provided with action button 16, the lower right side of action button 16 is provided with serial line interface 17, and the below of action button 16 is provided with debugging safe brace 18, ground connection branch/close handle 19 and operational mode diverter switch 20 from left to right.The circuit design of human and machine interface unit 6 is mainly considered the convenience of the man-machine interaction of bay device, can follow simultaneously tradition operation idea again, design the Chinesizing Liquid Crystal Module, numerous signal lamps, succinctly conductive rubber button easily is convenient to user's working service and operation.Be disposed with interchange module 21, CPU module 22, communication interface module 23, signal and breaker tripping and closing outlet module 24, power supply module 25, non electrical quantity outlet plug-in unit 26 and non electrical quantity plug-in unit 27 from right-to-left on the backboard 12.The single-chip microcomputer 1 of differential protection 100 is made up of CPU module 22 and peripheral circuit, and CPU module 22 can be realized differential protection and non electrical quantity protection.Exchange module 21 and be provided with the 1X01-1X24 binding post, amount to 24, wherein the left side is provided with the 1X13-1X24 binding post, and the right side is provided with the 1X01-1X12 binding post, comprising the three-phase input of four sides protection CT.

CPU module 22 is provided with the 2X01-2X22 binding post, amounts to 22, comprises 16 way switch amounts and a common port, is specially differential protection and drops into contact, standby opening into contact, and the distant signal in road is opened into contact, and all the other are standby; Realize the differential protection function.

Communication interface module 23 is provided with the 3X01-3X12 binding post, amounts to 12, and the bottom is provided with two Ethernet interface indicator lights and access port.

Signal and breaker tripping and closing outlet module 24 are provided with the 4X01-4X24 binding post, and 24 altogether, comprise the high-pressure side and export contact, medium voltage side outlet contact, low-pressure side outlet contact, alarm, plant failure contact are moved, protect in two groups of remote motion signals, protections.

Power supply module 25 is provided with the 5X01-5X12 binding post, amounts to 12, the middle part is provided with+5V and+the 24V power supply, the right side, bottom is provided with mains switch.

Non electrical quantity outlet plug-in unit 26 is provided with the 6X01-6X24 binding post, amounts to 24, comprises the lead-out terminal of non electrical quantity protection outlet; the remote motion signal of non electrical quantity, this body weight gas has load-carrying gas; the zero sequence choosing is jumped; pressure discharges, cooler fault, the light gas of body; the light gas of carrying is arranged; the temperature height, oil level is low, the contact that winding temperature is high

Non electrical quantity plug-in unit 27 is provided with the 7X01-7X24 binding post, amounts to 24, comprises this body weight gas export, and the load-carrying gas export is arranged; mouth is jumped out in the zero sequence choosing, and pressure discharges outlet, the outlet of cooler fault; protection tripping operation input, the input of this body weight gas has the input of load-carrying gas; input is jumped in the zero sequence choosing, and pressure discharges input, the input of cooler fault; the light gas input of body has and carries light gas input, the high input of temperature; the low input of oil level, the high input of winding temperature, and the input of non electrical quantity power supply.

Differential protection 100 can be realized differential protection: a, starting component; B, differential current fast tripping protection element; C, three sections broken line biased differential protection elements; D, secondary harmonic brake element; E, even-order harmonic braking member; F, the CT discriminating element that breaks; G, phase compensation; Can also realize the non electrical quantity protection.

Fig. 4 is the structural representation of reserve backboard 28 in the backup protection equipment 200 among Fig. 1; the structure of backup protection equipment 200 is identical with differential protection 100, just is disposed with reserve logic and tripping operation plug-in unit 29, back-up source module 30, reserve signal module 31, reserve breaker tripping and closing outlet module 32, reserve communication interface module 33 on its reserve backboard 28 from left to right, reserve CPU module 34 exchanges inputting modular unit 35 with reserve.

Wherein, reserve logic and tripping operation plug-in unit 29 are provided with the 1X01-1X24 binding post, amount to 24, specifically comprise: pressure is low forbids the input contact that trips, the input contact of the low quiescing of pressure, the input contact of the low No switching on of pressure, hand trip(ping) input contact, closing by hand input contact, control power supply input contact, hand is jumped the relay output contact, the outlet contact closes a floodgate, jump position relay output contact, the remote motion signal contact, the heavy movable contact in breaker closing position, the heavy movable contact in circuit breaker trip position, tripping operation outlet contact, close a relay tip, tripping operation inlet contact.

Back-up source module 30 is provided with the 2X01-2X12 binding post, amounts to 12, the middle part is provided with+5V and+the 24V power supply, the right side, bottom is provided with mains switch.

Reserve signal module 31 is provided with the 3X01-3X24 binding post, amounts to 24, wherein comprises two groups of guard signals, can be respectively as central signal and remote motion signal, and remote control is closed a floodgate and is exported contact, remote control tripping operation outlet contact, and the remote control spare contact.

Reserve breaker tripping and closing outlet module 32 is provided with the 4X01-4X24 binding post, amount to 24, wherein comprise high-pressure side outlet contact, medium voltage side outlet contact, low-pressure side outlet contact, the female connection outlet in high-pressure side contact, the female connection outlet of medium voltage side contact, the female connection outlet of low-pressure side contact.

Reserve communication interface module 33 is provided with the 5X01-5X12 binding post, amounts to 12, and the bottom is provided with two Ethernet interface indicator lights and access port.

Reserve CPU module 34 is provided with the 6X01-6X22 binding post, amounts to 22, comprises the direction overcurrent protection and drops into contact, zero sequence overcurrent protection input contact; Gap protection drops into contact; Press off again into/drop into contact; Press off again into two input contacts, the distant signal in road and open into contact.

Reserve exchanges inputting modular unit 35; be provided with the 7X01-7X24 binding post; amount to 24; wherein the left side is provided with the 7X13-7X24 binding post, and the right side is provided with the 7X01-7X12 binding post, comprising the three-phase input of protection CT, the input of zero-sequenceprotection CT; measure the input of CT; gap protection CT input, the input of busbar voltage three-phase and zero line, residual voltage input.Backup protection equipment 200 can be realized backup protection: a, backup protection starting component; B, alternate protection; C, ground protection; D, the overcurrent protection of residual voltage locking zero sequence; E, gap protection; Protection is jumped in f, zero sequence choosing; G, non-whole phase protection.

Claims

1; digital transformer protector; mainly comprise: differential protection (100); backup protection equipment (200) and main body protection device (300); it is characterized in that: differential protection (100) mainly comprises: single-chip microcomputer (1); DI opens into unit (2); AD sampling unit (3); DO leaves unit (4); communication unit (5); human and machine interface unit (6); power circuit unit (7); single-chip microcomputer (1) leaves into unit (2) with DI respectively by lead; AD sampling unit (3); DO leaves unit (4); communication unit (5); human and machine interface unit (6) links to each other with power circuit unit (7), and DO leaves unit (4) and links to each other with power circuit unit (7) by lead.

2; digital transformer protector according to claim 1; it is characterized in that: the single-chip microcomputer (1) of above-mentioned differential protection (100); DI opens into unit (2); AD sampling unit (3); DO leaves unit (4); communication unit (5); it is integrated that human and machine interface unit (6) and power circuit unit (7) are modularization; DI opens into unit (2); AD sampling unit (3); DO leaves unit (4); communication unit (5) and power circuit unit (7) are all by on the integrated backboard (12) that is fixed on casing (11) of modularization, and human and machine interface unit (6) is by on the integrated front panel (13) that is fixed on casing (11) of modularization.

3, digital transformer protector according to claim 2; it is characterized in that: the left side of front panel (13) middle and upper part is provided with liquid crystal display screen (14); the right side of liquid crystal display screen (14) is provided with indicator light (15); the below of liquid crystal display screen (14) is provided with action button (16); the lower right side of action button (16) is provided with serial line interface (17), and the below of action button (16) is provided with debugging safe brace (18), ground connection branch/close handle (19) and operational mode diverter switch (20) from left to right.

4, digital transformer protector according to claim 2 is characterized in that: backboard (12) is gone up from right-to-left and is disposed with interchange module (21), CPU module (22), communication interface module (23), signal and breaker tripping and closing outlet module (24), power supply module (25), non electrical quantity outlet plug-in unit (26) and non electrical quantity plug-in unit (27).

5, according to any described digital transformer protector of claim 1-4, it is characterized in that: the single-chip microcomputer (1) of differential protection (100) is made up of CPU module (22) and peripheral circuit.

6, digital transformer protector according to claim 1; it is characterized in that: the structure of backup protection equipment (200) is identical with differential protection (100), just is disposed with reserve logic and tripping operation plug-in unit (29), back-up source module (30), reserve signal module (31), reserve breaker tripping and closing outlet module (32), reserve communication interface module (33) on its reserve backboard (28) from left to right, reserve CPU module (34) exchanges inputting modular unit (35) with reserve.