CN101557101B - Relay protection method for eliminating failure in transformer dead zone - Google Patents
Relay protection method for eliminating failure in transformer dead zone Download PDFInfo
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- CN101557101B CN101557101B CN2008102013053A CN200810201305A CN101557101B CN 101557101 B CN101557101 B CN 101557101B CN 2008102013053 A CN2008102013053 A CN 2008102013053A CN 200810201305 A CN200810201305 A CN 200810201305A CN 101557101 B CN101557101 B CN 101557101B
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Abstract
The invention relates to a relay protection method, in particular to a relay protection method for eliminating failure in transformer dead zone. The invention designs two relay protection methods for eliminating the protection dead zones aiming at the condition that failures between the medium and low voltage side switches and current transformators can not be protected under the circumstance of folding a high voltage side switch to surge a main transformer and opening the medium and low voltage side switches. The main technical proposal of the invention is that main transformer differential protection is arranged on the main transformer, main transformer standby protection is arranged between the main transformer and each bus, and an over-current protection logic circuit is arranged in the main transformer standby protection when any non-high-voltage side switch is disconnected. When a circuit is overloaded or short cut, the over-current protection logic circuit trips off a circuit switch.
Description
Technical field
The present invention relates to a kind of relay protecting method, relate in particular to the relay protecting method of a kind of eliminating transformer dead band fault.
Background technology
According to " DL400-91 relaying protection and automatic safety device technical regulation " requirement; To transformer except that the necessary gas and differential protection of installing; To the transformer overcurrent that causes by outside phase fault; Should protect in support by the overcurrent protection that regulation is installed voltage blocking, after the protection action, the band time limit moves in tripping operation.
Because the main transformer impedance is bigger, when main transformer low-pressure side fault, high side voltage often descends less; Cause effectively to open the voltage blocking function; In practical application, adopt the open method of parallel connection, ability action message when guaranteeing the low-pressure side fault for this reason; Promptly adopt the voltage of high and low pressure side simultaneously, any one voltage descends can both open locked loop.
According to the regulation of operation, main transformer is gone into operation or is overhauled when using as a servant again, for preventing the main transformer fault, must throw and go up main transformer differential protection and the protection fully of high and low pressure rear flank.The differential protection scope is two all devices between the current transformer, if any the instantaneous tripping main transformer of fault high and low pressure side switch.The high and low pressure rear flank is equipped with the protection of protection for the reserve of differential protection and busbar fault, the corresponding switch of action back time-delay tripping.
The actual motion operating process is the high side switch impact main transformer that at first closes; Low-side switch is drawn back; If break down between the low-side switch summation current transformer this moment, owing to this fault is positioned at outside the differential protection scope, so differential protection can't move; And the voltage that the high-pressure side backup protection is got can't move opening because the main transformer impedance is big; Low-pressure side bus causes it can not excise fault fast because voltage normally can not start the open high-pressure side overcurrent protection in loop through parallel connection simultaneously, will cause that main transformer burns damage.Caused the protection dead band thus, shown in Figure 4.
Summary of the invention
The present invention impacts main transformer to transformer at the high side switch that closes; In, under the low-side switch situation about drawing back; In, can't protected situation between the low-side switch summation current transformer, designed two kinds of relay protecting methods of eliminating above-described protection dead bands.
Above-mentioned technical problem of the present invention is able to implement through following technical scheme:
Method 1: in the main transformer backup protection, the overcurrent protection logical circuit when being provided with arbitrary non-high side switch and breaking off, when overload or short trouble take place in the dead band, overcurrent protection logical circuit tripping respective switch, actual conditions such as Fig. 4, shown in Figure 6.
The relay protecting method of above-mentioned eliminating transformer dead band fault; As preferably, in the main transformer backup protection of two coil transformer high voltage bus sides, be provided with an AND; Its logic is: when low-side switch is broken off; And high voltage side current is jumped high side switch during greater than setting in required time, and it is as shown in Figure 5 that its logic is collected circuit.
The relay protecting method of above-mentioned eliminating transformer dead band fault; As preferably, in the main transformer backup protection of three coil transformer high voltage bus sides, be provided with one with or gate logic; Its logic is: when low-side switch is broken off or the disconnection of medium voltage side switch; And high voltage side current is during greater than setting, and high jump pressure in required time and low pressure both sides switch or high jump are in required time pressed and middle pressure both sides switch, and it is as shown in Figure 7 that its logic is collected circuit.
Method 2: in the main transformer backup protection, the overcurrent protection logical circuit when being provided with arbitrary non-high side switch and breaking off, when overload or short trouble take place in the dead band, overcurrent protection logical circuit tripping respective switch, actual conditions such as Fig. 4, shown in Figure 6.
The relay protecting method of above-mentioned eliminating transformer dead band fault; As preferably; In the main transformer backup protection of two coil transformer high voltage bus sides, be provided with an AND, its logic is: when low-side switch is broken off; And the low-pressure side electric current is jumped high side switch during greater than setting in required time.
The relay protecting method of above-mentioned eliminating transformer dead band fault; As preferably; In the main transformer backup protection of three coil transformer high voltage bus sides, be provided with an AND, its logic is: when low-side switch is broken off; And the low-pressure side electric current is during greater than setting, high jump in required time, middle pressure both sides switch.
The relay protecting method of above-mentioned eliminating transformer dead band fault; As preferably; In the main transformer backup protection of three coil transformer high voltage bus sides, be provided with an AND, its logic is: when the medium voltage side switch breaks off; And the medium voltage side electric current is during greater than setting, high jump in required time, low pressure both sides switch.
In sum, the present invention compares with prior art and has following advantage:
In, low-side switch breaks off, when high side switch closes, in, the charging equipment between the low-voltage circuit breaker summation current transformer also within the protection protection range, the situation of thoroughly having avoided main transformer to damage because of overcurrent.
Description of drawings
Fig. 1 is a transformer electrical equipment amount protection allocation plan;
Fig. 2 is a step down side backup protection logic;
Fig. 3 is a step down side backup protection logic;
Fig. 4 is a fault sketch map between the two coil transformer low-side switch summation current transformers;
Fig. 5 increases high-pressure side backup protection logic;
Fig. 6 is a fault sketch map between the three coil transformer medium voltage side switch summation current transformers;
Fig. 7 is that three coil transformer high-pressure side backup protections increase logic;
Fig. 8 is main transformer low-side switch operation circuit figure;
Fig. 9 be main transformer low-side switch operation circuit figure respectively distinguish functional block diagram;
Figure 10 is main transformer low-pressure side backup protection position of the switch lead-out terminal and main transformer high-pressure side backup protection switching value input terminal annexation figure;
Figure 11 be main transformer low-pressure side backup protection position of the switch lead-out terminal and main transformer high-pressure side backup protection switching value input terminal annexation figure respectively distinguish functional block diagram;
Figure 12 is that two coil transformer low-pressure side backup protections increase logic;
Figure 13 is that three coil transformer low-pressure side backup protections increase logic;
Figure 14 is that three coil transformer medium voltage side backup protections increase logic;
Figure 15 is two coil transformer main transformer high-pressure sides protection tripping operation terminal and main transformer low-pressure side protection tripping operation terminal annexation figure;
To be two coil transformer main transformer high-pressure sides protection tripping operation terminal respectively distinguish functional block diagram with terminal annexation figure is tripped in the protection of main transformer low-pressure side to Figure 16.
Embodiment
Through embodiment,, do further bright specifically below to technical scheme of the present invention in conjunction with accompanying drawing:
Embodiment 1:
The improvement that the present invention makes with reference to national transformer standard protective device design drawing, standard is JB/T5054-2001 and JB/T8823-1998.
The present invention does not do any change to the related hardware of main transformer protection and operation circuit, and its existing equipment need not change, and the part of modification is mainly the internal processes logic and increases the portion of external secondary connection.
Fig. 9 be Fig. 8 main transformer low-side switch operation circuit figure correspondence respectively distinguish functional block diagram.Among Fig. 8 each functional areas comprised operating power from top to bottom, jumped position supervisions, combined floodgate maintenance, reclosing, anti-jump, hand closes, hand is jumped, protection is tripped, tripping operation keeps, close a supervision, closing pressure, tripping operation pressure, air pressure deficiency.
Figure 11 is Figure 10 main transformer low-pressure side backup protection position of the switch lead-out terminal and the corresponding functional block diagram of respectively distinguishing of main transformer high-pressure side backup protection switching value input terminal annexation figure.The main transformer low-pressure side backup protection position of the switch lead-out terminal on Figure 10 top is respectively distinguished in the functional block diagram each functional areas and has been comprised remote signalling, the protection of main transformer reserve blind area from top to bottom, gone protection; Wherein remote signalling has comprised that low-side switch separating brake position, low-side switch closing position, accident resultant signal, control loop broken string, tripping operation pressure anomaly, closing pressure are unusual; Wherein main transformer reserve blind area protection has comprised low-side switch separating brake position, low-side switch closing position, wherein go protection to comprise to jump position, KK to close after.
Main transformer low-side switch operation circuit is not done any change, and is as shown in Figure 9, when low-side switch punishment gate position; Its position of the switch relay TWJ1, TWJ2, TWJ3 excitation; Show that switch separates, as shown in Figure 8, separating brake position relay tip 622,624 closures.As shown in Figure 8; Separating brake position relay tip one side 624 is received through inner optocoupler 24V power supply in the switching value importation of main transformer high-pressure side protection; When it is closed, current potential is fed back to the switching value input contact of protecting the high-pressure side through 622; This contact 309 is defined as low-side switch separating brake position by internal processes, changes internal logic simultaneously, makes it satisfy the effect of protection blind area fault.
The wiring of logic increase for a change; Shown in figure 10; Main transformer low-pressure side backup protection switch allocation position lead-out terminal 42D35 is connected with main transformer high-pressure side backup protection switching value input terminal 309, and main transformer low-pressure side backup protection position of the switch lead-out terminal 42D36 is connected with main transformer high-pressure side backup protection switching value input terminal 317.
In two coil transformers, original internal logic is: high side voltage less than setting or low-pressure side voltage less than setting and high voltage side current the time greater than setting, time-delay high jump, low pressure both sides switch, as shown in Figure 2; During less than setting, low-side switch is jumped in time-delay to the low-pressure side electric current, and is as shown in Figure 3 greater than setting and low-pressure side voltage.
In the main transformer backup protection of two coil transformer high voltage bus sides, the internal logic of increase is: when low-side switch is broken off, and high voltage side current jumps high side switch during greater than setting in required time, and is as shown in Figure 5.
Embodiment 2:
In three coil transformers, original internal logic is: high, medium and low voltage either side voltage is less than setting and high voltage side current greater than setting the time, the time-delay high jump, in, low pressure both sides switch; In, the low-pressure side electric current greater than setting and in, low-pressure side voltage is during less than setting, during time-delay is jumped, low-side switch.
In the main transformer backup protection of three coil transformer high voltage bus sides; The internal logic that increases is: when low-side switch is broken off or the disconnection of medium voltage side switch; And high voltage side current is during greater than setting; High jump pressure in required time and low pressure both sides switch or high jump are in required time pressed and middle pressure both sides switch, and be as shown in Figure 7.
All the other are provided with reference to embodiment 1.
Embodiment 3:
Like Figure 15, Figure 16, main transformer low-pressure side protection tripping operation terminal 21D18 links to each other with main transformer high-pressure side protection tripping operation terminal 31D39, main transformer low-pressure side protection tripping operation terminal 21D33 links to each other with main transformer high-pressure side protection tripping operation terminal 31D67, and all the other are like Fig. 8, shown in Figure 9.
In two coil transformers, original internal logic is: high side voltage less than setting or low-pressure side voltage less than setting and high voltage side current the time greater than setting, time-delay high jump, low pressure both sides switch, as shown in Figure 2; During less than setting, low-side switch is jumped in time-delay to the low-pressure side electric current, and is as shown in Figure 3 greater than setting and low-pressure side voltage.
In the main transformer backup protection of two coil transformer high voltage bus sides, the internal logic of increase is:
When low-side switch is broken off, and the low-pressure side electric current jumps high side switch during greater than setting in required time, and is shown in figure 12.
Embodiment 4:
In three coil transformers, original internal logic is: high, medium and low voltage either side voltage is less than setting and high voltage side current greater than setting the time, the time-delay high jump, in, low pressure both sides switch; In, the low-pressure side electric current greater than setting and in, low-pressure side voltage is during less than setting, during time-delay is jumped, low-side switch.
In the main transformer backup protection of three coil transformer high voltage bus sides, the internal logic of increase is:
When the medium voltage side switch breaks off, and the medium voltage side electric current is during greater than setting, and high jump in required time, low pressure both sides switch are shown in figure 13.
When low-side switch is broken off, and the low-pressure side electric current is during greater than setting, and high jump in required time, middle pressure both sides switch are shown in figure 14.
All the other are provided with reference to embodiment 3.
Specific embodiment described herein only is that the present invention's spirit is illustrated.Person of ordinary skill in the field of the present invention can make various modifications or replenishes or adopt similar mode to substitute described specific embodiment, but can't depart from spirit of the present invention or surmount the defined scope of appended claims.
Claims (6)
1. the relay protecting method of an eliminating transformer dead band fault; On main transformer, be provided with the main transformer differential protection, also be provided with the main transformer backup protection between main transformer and each bus, it is characterized in that; In the main transformer backup protection; Overcurrent protection logical circuit when being provided with arbitrary non-high side switch and breaking off, when circuit overloads or short circuit, overcurrent protection logical circuit tripping circuit switch.
2. the relay protecting method of eliminating transformer according to claim 1 dead band fault; It is characterized in that; In the main transformer backup protection of two coil transformer high voltage bus sides, be provided with an AND, its logic is: when low-side switch is broken off; And high voltage side current is jumped high side switch during greater than setting in required time.
3. the relay protecting method of eliminating transformer according to claim 1 dead band fault; It is characterized in that; In the main transformer backup protection of three coil transformer high voltage bus sides, be provided with one with or gate logic, its logic is: when low-side switch is broken off or the medium voltage side switch breaks off; And high voltage side current is during greater than setting, and high jump pressure in required time and low pressure both sides switch or high jump are in required time pressed and middle pressure both sides switch.
4. the relay protecting method of eliminating transformer according to claim 1 dead band fault; It is characterized in that; In two coil transformer low pressure backup protections, be provided with an AND, its logic is: when low-side switch is broken off; And the low-pressure side electric current is jumped high side switch during greater than setting in required time.
5. the relay protecting method of eliminating transformer according to claim 1 dead band fault; It is characterized in that; In the main transformer backup protection of three coil transformer high voltage bus sides, be provided with an AND, its logic is: when low-side switch is broken off; And the low-pressure side electric current is during greater than setting, high jump in required time, middle pressure both sides switch.
6. the relay protecting method of eliminating transformer according to claim 1 dead band fault; It is characterized in that; In the main transformer backup protection of three coil transformer high voltage bus sides, be provided with an AND, its logic is: when the medium voltage side switch breaks off; And the medium voltage side electric current is during greater than setting, high jump in required time, low pressure both sides switch.
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| Application Number | Priority Date | Filing Date | Title |
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| CN2008102013053A CN101557101B (en) | 2008-10-14 | 2008-10-14 | Relay protection method for eliminating failure in transformer dead zone |
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| CN2008102013053A CN101557101B (en) | 2008-10-14 | 2008-10-14 | Relay protection method for eliminating failure in transformer dead zone |
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| CN101557101B true CN101557101B (en) | 2012-06-20 |
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| CN101800415B (en) * | 2010-04-27 | 2012-07-04 | 宁夏回族自治区电力公司 | Longitudinal differential protection method of electric furnace transformer |
| CN103779840B (en) * | 2012-10-18 | 2017-06-23 | 中国电力科学研究院 | Connection cutting system |
| CN103001195B (en) * | 2012-11-13 | 2016-04-27 | 江苏省电力公司镇江供电公司 | The relay protecting method of failure in transformer dead zone and the circuit breaker tripping of fault side |
| CN103166180B (en) * | 2013-03-25 | 2016-12-28 | 广东电网公司东莞供电局 | Power system transformer judges the method and device of overload cutting load |
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| CN103633621B (en) * | 2013-12-03 | 2017-05-10 | 国家电网公司 | Short-time opening protection based transformer dead zone fault relay protection method |
| CN103762553A (en) * | 2014-01-27 | 2014-04-30 | 国家电网公司 | Relay protection method for accelerated removal of dead zone faults of transformer based on open positions of circuit breakers |
| CN103762551A (en) * | 2014-01-27 | 2014-04-30 | 国家电网公司 | Relay protection method for accelerated removal and TA sealing of dead zone faults of transformer based on open positions of circuit breakers |
| CN104993460A (en) * | 2015-06-21 | 2015-10-21 | 南京南瑞继保电气有限公司 | Improvement method of simple bus protection |
| CN106786426B (en) * | 2017-01-17 | 2019-03-05 | 北京四方继保自动化股份有限公司 | The comprehensive distinguishing method of one Ge Ban main electrical scheme substation dead-zone fault |
| CN108459233B (en) * | 2018-03-27 | 2024-01-19 | 深圳供电局有限公司 | Equivalent circuit of main transformer high-voltage two-phase disconnection fault and identification method |
| CN109861181B (en) * | 2019-04-02 | 2020-10-16 | 国网江苏省电力有限公司镇江供电分公司 | Relay protection method for eliminating dead zone faults of sectional and bus-coupled circuit breakers |
| CN109861180B (en) * | 2019-04-02 | 2020-10-16 | 国网江苏省电力有限公司镇江供电分公司 | Bus differential protection locking spare power automatic switching protection method for preventing dead zone fault of sectional breaker |
| CN109980615B (en) * | 2019-04-02 | 2020-12-01 | 国网江苏省电力有限公司镇江供电分公司 | Relay protection method for eliminating dead zone faults of sectional circuit breaker and bus-tie circuit breaker |
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| US5790357A (en) * | 1994-05-03 | 1998-08-04 | Siemens Aktiengesellschaft | Differential current protection for a transformer |
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