Using method of three-phase inconsistent loop of 330kV circuit breaker and time relay

Abstract

The invention discloses a use method of three-phase inconsistent loops of a 330kV circuit breaker, and relates to the field of power systems, which comprises the following steps: when the three-phase loops are inconsistent, normally closed switches in the three-phase loops are closed, so that a time relay module is electrified; after the time relay module is electrified, the two normally open switches of the time relay module are closed, the first normally open switch is closed, the self-holding relay is electrified, and at the moment, the two normally open switches of the self-holding relay are closed; when the second normally-open switch is closed and the second normally-open switch of the self-holding relay is closed, the outlet relay is powered on; after the outlet relay is electrified, the normally open switch of the outlet relay is closed, and the tripping coil connected in series with the normally open switch of the outlet relay is electrified; and after the tripping coil is electrified, the electrified normally open switch of the tripping coil is closed to output a signal. Tripping caused by mistaken touch is avoided, meanwhile, through circuit adjustment, the circuit breaker protection device can adapt to circuit breakers of different models, and the expansibility is high.

Description

Technical Field

[0001] This invention relates to the field of power systems, and in particular to a method for using a three-phase inconsistent circuit of a 330kV circuit breaker and a time relay. Background Technology

[0002] With the development of power systems towards higher voltage and larger capacity, circuit breakers at voltage levels of 330kV and above generally adopt a phase-by-phase operation structure. However, during operation, inconsistent operation of three-phase circuit breakers often occurs due to equipment aging, operating mechanism failure, or human error, leading to zero-sequence and negative-sequence currents and threatening the stable operation of the power grid. Traditional three-phase inconsistency protection circuits have the following problems: 1. Insufficient reliability of time relays: Traditional circuits rely on a single time relay, which is prone to failure to operate or maloperation due to contact oxidation or aging in harsh environments. 2. Accidental tripping due to accidental contact: The tripping circuit is directly connected to the positive terminal of the power supply. Accidental contact with the output relay or time relay contacts may directly trigger the circuit breaker to trip, causing an accident. 3. Signal cannot be self-held: After the protection action, the signal disappears briefly, which is not conducive to fault analysis. Existing time relays typically use a structure combining foam pads and plastic blocks to fix the LCD screen and conductive strip. Then, a PCB board and interface frame are used to press the plastic block, foam pads, conductive strip, and LCD screen together. Patent publication number 201611166902.8 discloses a time relay structure. However, the installation structure, which causes the elastic swing arm to bend by pressing, is not stable enough. It is prone to reset under vibration, making the installation of the LCD screen and conductive strip unstable. Summary of the Invention

[0003] Therefore, the technical problem to be solved by the present invention is to solve the technical problem that the circuit is prone to tripping due to accidental contact.

[0004] The above-mentioned technical problems are solved by the following technical solution: The present invention proposes a method for using a three-phase inconsistent circuit of a 330kV circuit breaker, which includes closing the normally open switch in the three-phase circuit when the three-phase circuit is inconsistent, and energizing the time relay module connected in series with the normally open switch.

[0005] After the time relay module is energized, its two normally open switches close. When the first normally open switch closes, the self-holding relay is energized, and at this time, the two normally open switches of the self-holding relay close. When the second normally open switch closes, and the second normally open switch of the self-holding relay closes, the output relay is energized.

[0006] When the output relay is energized, its normally open switch closes, and the trip coil connected in series with the normally open switch of the output relay is energized.

[0007] After the trip coil is energized, the normally open switch energized by the trip coil closes and outputs a signal.

[0008] In a preferred embodiment of the method for using the three-phase inconsistent circuit of the 330kV circuit breaker described in this invention: the time relay module is composed of two identical time relays connected in parallel. When one of the time relay modules fails, the circuit remains connected, thus avoiding single-point failure.

[0009] In a preferred embodiment of the method of using the three-phase inconsistent circuit of the 330kV circuit breaker described in this invention: when the self-holding relay is energized, the LED light connected in parallel with the self-holding relay lights up. Power can only be cut off by pressing the reset button. The lighting of the LED light indicates that the circuit has been activated and needs to be checked.

[0010] To address the aforementioned technical problems, this invention also proposes a time relay: a clamping assembly for stably clamping the LCD screen and conductive strip within the relay housing.

[0011] A limiting component is provided on the clamping component to prevent the LCD screen and conductive strip from becoming unstable during installation due to the reset of the clamping component.

[0012] A suction assembly is disposed on the pressing assembly. The movement of the limiting assembly drives the suction assembly to firmly suction the LCD screen onto the pressing assembly.

[0013] In a preferred embodiment of the time relay of the present invention: the clamping assembly includes an L-shaped plate, two clamping plates disposed on the L-shaped plate, and a connecting plate disposed on the two clamping plates.

[0014] In a preferred embodiment of the time relay of the present invention: the limiting component includes a push rod movably disposed on the connecting plate, a limiting part disposed on the L-shaped plate, and a pushing part disposed on the limiting part. The limiting part is used to limit and lock the push rod, while the pushing part drives the suction component to suction the LCD screen.

[0015] In a preferred embodiment of the time relay of the present invention: the limiting part includes a first fixed plate disposed around the L-shaped plate, a turntable rotatably disposed on the first fixed plate, a limiting block disposed on the end face of the first fixed plate facing the turntable, and a ratchet disposed on the end face of the turntable facing the first fixed plate and engaging with the limiting block; the end of the push rod away from the connecting plate is movably disposed on the end face of the turntable away from the first fixed plate.

[0016] In a preferred embodiment of the time relay of the present invention, it further includes a pushing part, the pushing part including a driven plate movably disposed at one end on the turntable, the driven plate being located on the side of the turntable away from the ratchet, the other end of the driven plate being connected to the upright plate, and a first connecting block disposed on the upright plate and connected to the suction assembly.

[0017] In a preferred embodiment of the time relay of the present invention, a guide assembly is further included. The guide assembly includes a second fixing plate disposed on the first fixing plate and a guide plate disposed on the second fixing plate. The guide plate is provided with a groove for sliding friction with the upright plate.

[0018] In a preferred embodiment of the time relay of the present invention: the suction assembly includes a suction cup for suctioning the liquid crystal screen, a fixed cylinder disposed on the suction cup, and a sliding rod with one end slidably disposed inside the fixed cylinder and the other end cooperating to pass through the fixed cylinder, and the sliding rod is connected to the second connecting block.

[0019] The beneficial effects of this invention are as follows: the circuit can only be connected and tripped when the time relay is energized, avoiding tripping caused by accidental contact. At the same time, through circuit adjustment, it can adapt to different types of circuit breakers and has strong expandability. The installation steps of the internal LCD screen and conductive strip of the relay are simple and the installation stability is high. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention. Wherein:

[0021] Figure 1 A schematic diagram of the circuit structure of the present invention is shown;

[0022] Figure 2 A schematic diagram of the time relay of the present invention is shown;

[0023] Figure 3 A schematic diagram of the clamping assembly of the present invention is shown;

[0024] Figure 4 A partial cross-sectional view of the clamping assembly of the present invention is shown;

[0025] Figure 5 A schematic diagram of the structure of the limiting component of the present invention is shown. Figure 1 ;

[0026] Figure 6 A schematic diagram of the structure of the limiting component of the present invention is shown. Figure 2 . Detailed Implementation

[0027] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0028] The terminology used in this invention is that which is currently widely used in the art in consideration of the function of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new technology in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terms used in this specification should not be construed as simple names, but rather based on their meanings and the overall description of the invention.

[0029] Reference Figure 1 This embodiment provides a method for using a three-phase inconsistent circuit of a 330kV circuit breaker, including...

[0030] When the three-phase circuits are inconsistent, the normally closed switch in the three-phase circuit is closed, and the time relay module connected in series with the normally closed switch is energized.

[0031] like Figure 1 As shown, after the time relay module is energized, the two normally open switches of the time relay module close. When the first normally open switch closes, the self-holding relay N (represented by the letter N in the figure) is energized, and at this time, the two normally open switches of the self-holding relay N close. When the second normally open switch closes, and the second normally open switch N-2 (represented by the letter N-2 in the figure) of the self-holding relay N closes, the output relay BCJ is energized.

[0032] When the output relay BCJ is energized, its normally open switch closes, and the trip coil TQ, which is connected in series with the normally open switch of the output relay BCJ, is energized.

[0033] When the trip coil TQ is energized, the normally open switch of the energized trip coil TQ closes and outputs a signal. The trip coil TQ will only output a signal when the time relay module KT is energized, thus avoiding accidental activation.

[0034] Furthermore, the time relay module consists of two identical time relays KT connected in parallel. When one of the time relays KT fails, the circuit remains connected, avoiding single-point failure.

[0035] As an optional embodiment, when the self-holding relay is energized, the LED connected in parallel with the self-holding relay lights up. Power can only be cut off by pressing the reset button FA. The lighting of the LED indicates that the circuit has been activated and needs to be checked.

[0036] In summary, a three-phase circuit includes a power supply circuit, a self-holding circuit, an output relay circuit, and a tripping circuit, which are connected in parallel in the circuit.

[0037] like Figure 1 As shown, the power supply circuit includes three-phase normally open switches DLA1, DLB1, and DLC1, DLA1, DLB1, and DLC1 connected in parallel; three-phase normally closed switches DLA2, DLB2, and DLC2, DLA2, DLB2, and DLC2 connected in parallel; and a time relay module, with the three-phase normally open switches, three-phase normally closed switches, and time relay module connected in series.

[0038] like Figure 1 As shown, the self-holding circuit includes a second normally open switch of the time relay module and a self-holding relay N. The second normally open switch of the time relay module is connected in series with the self-holding relay N. The first normally open switch N-1 of the self-holding relay N is connected in series with the second normally open switch of the time relay module and closes after the self-holding relay N is energized.

[0039] like Figure 1 As shown, the output relay circuit includes a first normally open switch of the time relay module, an output relay BCJ, and a second normally open switch N-2 of the self-holding relay N, which are connected in series.

[0040] like Figure 1 As shown, the trip circuit includes the normally open switches of the output relay BCJ (BCJ-1, BCJ-2, and BCJ-3, BCJ-1, BCJ-2, and BCJ-3 connected in series), and the trip coil TQ. The normally open switch of the output relay BCJ is connected in series with the trip coil TQ. After the trip coil TQ is energized, the normally open switches of the trip coil TQ (TQA-1, TQB-1, and TQC-1) close to output a signal.

[0041] like Figure 2 - Figure 6 As shown, further, based on the above-mentioned 330kV circuit breaker three-phase inconsistency circuit, the present invention also provides a time relay, a clamping assembly 1, for stably clamping the LCD screen and the conductive strip inside the relay housing.

[0042] Limiting component 2 is set on clamping component 1 to prevent the LCD screen and conductive strip from being unstable during installation due to the reset of clamping component 1.

[0043] The suction component 3 is disposed on the pressing component 1. The movement of the limiting component 2 drives the suction component 3 to firmly suction the LCD screen onto the pressing component 1.

[0044] As an optional embodiment, the clamping assembly 1 includes an L-shaped plate 11, two clamping plates 12 disposed on the L-shaped plate 11, and a connecting plate 13 disposed on the two clamping plates 12. The L-shaped plate 11 is installed inside the relay housing and is used to clamp the LCD screen and conductive strip against the inner wall of the relay housing. The length of the clamping plate 12 is greater than the length of the L-shaped plate 11. When the clamping plate 12 is pressed down, the clamping plate 12 is pressed against the inner wall of the relay housing, and the reaction force of the inner wall of the relay housing acting on the clamping plate 12 pushes the L-shaped plate 11 to clamp the LCD screen and conductive strip.

[0045] As an optional embodiment, the limiting component 2 includes a push rod 21 movably disposed on the connecting plate 13, a limiting part 22 disposed on the L-shaped plate 11, and a pushing part 23 disposed on the limiting part 22. The limiting part 22 is used to limit and lock the push rod 21, while the pushing part 23 drives the suction component 3 to suction the LCD screen.

[0046] As an optional embodiment, the limiting part 22 includes a first fixing plate 221 disposed around the L-shaped plate 11, a turntable 222 rotatably disposed on the first fixing plate 221, a limiting block 223 disposed on the end face of the first fixing plate 221 facing the turntable 222, and a ratchet 224 disposed on the end face of the turntable 222 facing the first fixing plate 221 and engaged with the limiting block 223 for locking. The end of the pushing rod 21 away from the connecting plate 13 is movably disposed on the end face of the turntable 222 away from the first fixing plate 221. The clamping plate 12 presses against the inner wall of the relay housing, driving the connecting plate 13 to move, thereby pushing the pushing rod 21, causing the turntable 222 to rotate. The limiting block 223 controls the ratchet 214, thereby fixing the turntable 222 and locking the clamping plate 12, preventing the clamping plate 12 from resetting, and improving the stability of the installation of the LCD screen and conductive strip.

[0047] As an optional embodiment, a pushing unit 23 is also included. The pushing unit 23 includes a driven plate 231 movably mounted on the turntable 222 at one end, with the driven plate 231 located on the side of the turntable 222 away from the ratchet 224. The other end of the driven plate 231 is connected to the upright plate 232. A first connecting block 233 is mounted on the upright plate 232 and connected to the suction assembly 3. When the turntable 222 rotates, it causes the driven plate 231 to swing, thereby causing the other end of the driven plate 231 to move the upright plate 232 and the first connecting block 233. The suction assembly 3 mounted on the pushing unit 23 moves synchronously.

[0048] As an optional embodiment, the upright plate 232 is perpendicular to the first connecting block 233, and the upright plate 232 is parallel to the suction assembly 3.

[0049] like Figure 6As shown, it also includes a guide assembly 4, which includes a second fixed plate 41 disposed on the first fixed plate 221 and a guide plate 42 disposed on the second fixed plate 41. The guide plate 42 is provided with a groove 421 for sliding friction with the upright plate 232. The upright plate 232 is provided with a slider 234 that cooperates with the groove 421. The cooperation between the slider 234 and the groove 421 can limit the movement direction of the upright plate 232, so that the first connecting block 233 is only subjected to a force in the vertical direction, which can drive the suction assembly 3 to slide upward, avoiding the suction assembly 3 being subjected to an oblique upward force, which would cause the suction assembly 3 to deform and be damaged.

[0050] As an optional embodiment, the suction assembly 3 includes a suction cup 31 for suctioning the LCD screen, a fixing cylinder 32 disposed on the suction cup 31, and a sliding rod 33 with one end slidably disposed inside the fixing cylinder 32 and the other end cooperating to pass through the fixing cylinder 32, and the sliding rod 33 is connected to the second connecting block 43.

[0051] As an optional embodiment, it also includes a connecting rod 6. The suction assembly 3 is provided in two sets, and the two sets of suction assemblies 3 are arranged side by side. The two ends of the connecting rod 6 are respectively connected to two sliding rods 33, and the connecting rod 6 is connected to the second connecting block 43.

[0052] In summary, by pressing the clamping plate 12, the connecting plate 13 pushes the push rod 21, causing the turntable 222 to swing, which in turn drives the ratchet 224 to swing. The limiting block 223 then limits the ratchet 224, preventing the clamping plate 12 from resetting after deformation, thus making the installation of the LCD screen and conductive strip more stable. At the same time, when the turntable 222 swings, it drives the driven plate 231 to swing, causing the upright plate 232 and the first connecting block 233 to move upward, pulling the sliding rod 33 upward, and creating a vacuum inside the suction cup 31, thereby suctioning the LCD screen onto the L-shaped plate 11 for stable installation. During the process of the clamping plate 12 being pressed down and deformed, the L-shaped plate 11 presses against the LCD screen, thereby sealing and pressing the suction cup 31 against the LCD screen, and further fixing the LCD screen by vacuuming.

[0053] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of the present invention.

Claims

1. A method for using a three-phase inconsistent circuit in a 330kV circuit breaker, characterized in that: Specifically, it includes the following steps: When the three-phase circuits are inconsistent, the normally open switch in the three-phase circuit is closed, and the time relay module connected in series with the normally open switch is energized. After the time relay module is energized, its two normally open switches close. The closure of the first normally open switch energizes the self-holding relay, at which point the two normally open switches of the self-holding relay close. When the second normally open switch closes, and the second normally open switch of the self-holding relay also closes, the output relay is energized. When the output relay is energized, its normally open switch closes, and the trip coil connected in series with the normally open switch of the output relay is energized. After the trip coil is energized, the normally open switch energized by the trip coil closes and outputs a signal.

2. The method of using the three-phase inconsistent circuit of the 330kV circuit breaker according to claim 1, characterized in that: The time relay module consists of two identical time relays connected in parallel. When one of the time relays fails, the circuit remains connected, thus avoiding single-point failure.

3. The method of using the three-phase inconsistent circuit of the 330kV circuit breaker according to claim 1, characterized in that: When the self-holding relay is energized, the LED connected in parallel with the self-holding relay lights up. Power can only be cut off by pressing the reset button. The LED lighting up indicates that the circuit has been activated and needs to be checked.

4. A time relay, characterized in that: Including the 330kV circuit breaker three-phase inconsistency circuit as described in any one of claims 1-3, it also includes, A clamping assembly (1) is used to stably clamp the LCD screen and the conductive strip inside the relay housing; A limiting component (2) is disposed on the clamping component (1) to prevent the clamping component (1) from resetting and causing instability in the installation of the LCD screen and conductive strip; and The suction component (3) is disposed on the pressing component (1). The movement of the limiting component (2) drives the suction component (3) to firmly suction the LCD screen onto the pressing component (1).

5. The time relay according to claim 4, characterized in that: The clamping assembly (1) includes an L-shaped plate (11), two clamping plates (12) disposed on the L-shaped plate (11), and a connecting plate (13) disposed on the two clamping plates (12).

6. The time relay according to claim 5, characterized in that: The limiting component (2) includes a push rod (21) movably disposed on the connecting plate (13), a limiting part (22) disposed on the L-shaped plate (11), and a pushing part (23) disposed on the limiting part (22). The limiting part (22) is used to limit and lock the push rod (21), while the pushing part (23) drives the suction component (3) to suction the LCD screen.

7. The time relay according to claim 6, characterized in that: The limiting part (22) includes a first fixing plate (221) disposed around the L-shaped plate (11), a turntable (222) rotatably disposed on the first fixing plate (221), a limiting block (223) disposed on the end face of the first fixing plate (221) facing the turntable (222), and a ratchet (224) disposed on the end face of the turntable (222) facing the first fixing plate (221) and engaged with the limiting block (223); the end of the push rod (21) away from the connecting plate (13) is movably disposed on the end face of the turntable (222) away from the first fixing plate (221).

8. The time relay according to claim 7, characterized in that: The pushing part (23) includes a driven plate (231) with one end movably disposed on the turntable (222), and the driven plate (231) is located on the side of the turntable (222) away from the ratchet (224), the other end of the driven plate (231) is connected to the upright plate (232), and a first connecting block (233) disposed on the upright plate (232) and connected to the suction assembly (3).

9. The time relay according to claim 8, characterized in that: It also includes a guide assembly (4), which includes a second fixing plate (41) disposed on the first fixing plate (221) and a guide plate (42) disposed on the second fixing plate (41), and the guide plate (42) is provided with a groove (421) for sliding friction with the upright plate (232).

10. The time relay according to claim 9, characterized in that: The suction assembly (3) includes a suction cup (31) for suctioning the LCD screen, a fixed cylinder (32) disposed on the suction cup (31), and a sliding rod (33) with one end slidably disposed inside the fixed cylinder (32) and the other end cooperating to pass through the fixed cylinder (32), and the sliding rod (33) is connected to the second connecting block (43).

Images