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 implemented by the following technical programs:
Method 1: in the main transformer backup protection, the overcurrent protection logical circuit when being provided with arbitrary non-high side switch and disconnecting, 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 disconnects; and high voltage side current is during greater than setting, high jump in required time, low pressure both sides switch, and its logic is collected circuit as shown in Figure 5.
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 disconnects or the disconnection of medium voltage side switch; and high voltage side current is jumped high, medium and low voltage both sides switch during greater than setting in required time, and its logic is collected circuit as shown in Figure 7.
Method 2: in the main transformer backup protection, the overcurrent protection logical circuit when being provided with arbitrary non-high side switch and disconnecting, 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 disconnects; 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 disconnects; 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 disconnects; 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 disconnects, 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 that transformer low voltage is surveyed the backup protection logic;
Fig. 3 is that transformer low voltage is surveyed the backup protection logic;
Fig. 4 is a fault schematic diagram between the two coil transformer low pressure slowdown monitoring switch summation current transformers;
Fig. 5 increases high-pressure side backup protection logic;
Fig. 6 presses fault schematic diagram between the slowdown monitoring switch summation current transformer in three coil 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
Below by embodiment, in conjunction with the accompanying drawings, technical scheme of the present invention is described in further detail:
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 a position supervision, 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, as shown in Figure 9, and 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 by 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 by 622; this contact 309 is defined as low-side switch separating brake position by internal processes; change internal logic simultaneously, make it satisfy the effect of protection blind area fault.
The wiring of logic increase for a change; as 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, 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 disconnects, and high voltage side current is during greater than setting, high jump in required time, low pressure both sides switch, as shown in Figure 5.
Embodiment 2:
In three coil transformers, original internal logic is: greater than setting the time, high, medium and low voltage both sides switch is jumped in time-delay to high, medium and low voltage either side voltage less than setting and high voltage side current; 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 disconnects or the disconnection of medium voltage side switch; and high voltage side current is jumped high, medium and low voltage both sides switch, as shown in Figure 7 during greater than setting in required time.
All the other are provided with reference to embodiment 1.
Embodiment 3:
As 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 as 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, 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 disconnects, and the low-pressure side electric current is jumped high side switch, as shown in figure 12 during greater than setting in required time.
Embodiment 4:
In three coil transformers, original internal logic is: greater than setting the time, high, medium and low voltage both sides switch is jumped in time-delay to high, medium and low voltage either side voltage less than setting and high voltage side current; 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 disconnects, and the medium voltage side electric current is during greater than setting, high jump in required time, low pressure both sides switch, as shown in figure 13.
When low-side switch disconnects, and the low-pressure side electric current is during greater than setting, high jump in required time, middle pressure both sides switch, as 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.The technical staff of the technical field of the 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.