Six-column composite full-phase voltage-limiting monitoring device

Abstract

The invention discloses a six-column composite full-phase voltage limiting monitoring device, and relates to the technical field of power protection, the device comprises a monitoring device body, a first disconnector, a second disconnector and a third disconnector, and the disconnectors are installed on the monitoring device body; the electrical principle structure inside the monitoring device body is as follows: an A-phase connection point is connected with a C-phase connection point through a first non-linear resistor, the A-phase connection point is grounded through a second non-linear resistor, the A-phase connection point is connected with a B-phase connection point through a third non-linear resistor, the B-phase connection point is grounded through a fourth non-linear resistor, and the C-phase connection point is grounded through a third non-linear resistor. The B-phase connection point is connected with the C-phase connection point through a fifth non-linear resistor, and the C-phase connection point is grounded through a sixth non-linear resistor; the first disconnector is connected with an A-phase connection point, the second disconnector is connected with a B-phase connection point, and the third disconnector is connected with a C-phase connection point. And various inter-phase and phase-ground overvoltage of the system can be comprehensively suppressed.

Description

Technical Field

[0001] The invention relates to the technical field of power protection, and in particular to a six-column composite full-phase voltage-limiting monitoring device. Background Art

[0002] Lightning arresters are used to protect electrical equipment from high transient overvoltage hazards during lightning strikes, and to limit the follow-on time, and often also limit the follow-on amplitude. Lightning arresters are sometimes also called overvoltage protectors and overvoltage limiters. In the related art, the three phases (phase A, phase B, and phase C) of the four-column protector are all connected to a common terminal D through a high-energy capacity valve plate to release energy relative to the ground, and pass through a high-energy capacity valve plate before grounding. When there is a problem with the common terminal, the three phases ABC cannot work, and the entire device does not have a protection function. Based on this, the present invention proposes a six-column composite full-phase voltage limiting monitoring device. Summary of the invention

[0003] The present invention provides a six-column composite full-phase voltage-limiting monitoring device, which can comprehensively suppress various overvoltages between phases and between phases and ground of a system.

[0004] According to one aspect of the present disclosure, a six-column composite full-phase voltage-limiting monitoring device is provided, the device comprising: a monitoring device body, a first disconnector, a second disconnector, and a third disconnector, wherein the disconnector is mounted on the monitoring device body; The electrical principle structure inside the monitoring device body is as follows: The A-phase connection point is connected to the C-phase connection point through a first nonlinear resistor, the A-phase connection point is grounded through a second nonlinear resistor, the A-phase connection point is connected to the B-phase connection point through a third nonlinear resistor, the B-phase connection point is grounded through a fourth nonlinear resistor, the B-phase connection point is connected to the C-phase connection point through a fifth nonlinear resistor, and the C-phase connection point is grounded through a sixth nonlinear resistor; The first disconnector is connected to the A phase connection point, the second disconnector is connected to the B phase connection point, and the third disconnector is connected to the C phase connection point; The current signals of the first disconnector, the second disconnector and the third disconnector are respectively collected by three current sensors.

[0005] In one possible implementation, the disconnector includes a copper link wire, an inner cylinder, quartz sand, a disconnect wire, an outer cylinder, and a conductive link rod, wherein the inner cylinder is wrapped with a disconnect wire, one end of the disconnect wire is connected to the conductive link rod, and the other end of the disconnect wire is connected to the copper link wire, the outer cylinder is sheathed on the outside of the inner cylinder, and the gap between the inner cylinder and the outer cylinder is filled with quartz sand.

[0006] In a possible implementation, the disconnector also includes a silicone rubber sheath, a high-voltage cable, and a wiring copper nose, wherein the silicone rubber sheath is arranged on the outside of the outer cylinder, the copper link wire is connected to the first end of the high-voltage cable, and the second end of the high-voltage cable is connected to the wiring copper nose; the wiring copper nose is connected to the protected system.

[0007] In a possible implementation, when overvoltage occurs in the power system to which the six-column composite full-phase voltage limiting monitoring device is connected, the overvoltage is absorbed by a nonlinear resistor.

[0008] In a possible implementation, the disconnector is used to automatically fuse the disconnect wire when a nonlinear resistor fails.

[0009] In one possible implementation, the device is also connected to a processor and a display screen, the processor is used to process the current data of the nonlinear resistor, and the display screen is used to display the fault phase sequence, time, and leakage current value; the processor monitors the leakage current values ​​between phases and between phases and ground, and displays the degradation process of the nonlinear resistor in three levels, 1mA-500mA is the first level, which is the normal range, 500mA-1000mA is the second level, indicating that the valve plate is slightly degraded, and greater than 1001mA is the third level, indicating that the valve plate is severely degraded.

[0010] Compared with the prior art, the present invention has the following beneficial effects: A six-column composite full-phase voltage-limiting monitoring device, which is composed of 3 sets of delta-connected and 3 sets of star-connected piezoresistors (zinc oxide valve plates), 3 sets of phase-to-phase protection, and 3 sets of phase-to-ground protection, which operate independently without interfering with each other. It fully suppresses various overvoltages between phases and between phases and ground of the system (including lightning overvoltage, atmospheric overvoltage, operating overvoltage and system transient overvoltage, etc.). The protection performance is more reliable and safer than that of conventional four-star overvoltage protectors.

[0011] The absorption of 2MS square wave current of the six-column composite full-phase voltage limiting monitoring device is increased to 1200A, which is a significant improvement compared to about 800A in the prior art.

[0012] The disconnector realizes online monitoring of the entire life cycle and the online status of whether the disconnector is disconnected. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 A schematic diagram of a four-post protector according to an embodiment of the present disclosure is shown.

[0014] Figure 2 A schematic diagram of a six-pillar composite protector according to an embodiment of the present disclosure.

[0015] Figure 3 A physical diagram of a six-column composite full-phase voltage limiting monitoring device according to an embodiment of the present disclosure is shown.

[0016] Figure 4 The external structure diagram of a disconnector according to an embodiment of the present disclosure is shown.

[0017] Figure 5 The internal structure diagram of the disconnector according to one embodiment of the present disclosure is shown.

[0018] Figure 6 A physical diagram of a release wire according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0019] Various exemplary embodiments, features and aspects of the present disclosure will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0020] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0021] In addition, in order to better illustrate the present disclosure, numerous specific details are given in the following specific embodiments. It should be understood by those skilled in the art that the present disclosure can also be implemented without certain specific details. In some examples, methods, means, components and circuits well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present disclosure.

[0022] Figure 1 The schematic diagram of a four-column protector according to an embodiment of the present disclosure is shown. Figure 1 It can be seen that the three phases (A, B, and C) of the four-column protector are connected to a common terminal D through a high-energy capacity valve plate to release energy relative to the ground, and pass through a high-energy capacity valve plate before grounding. When a problem occurs at the common terminal, the three phases ABC cannot work, and the entire device has no protection function.

[0023] A six-column composite full-phase voltage-limiting monitoring device, the device comprising: a monitoring device body, a first disconnector, a second disconnector, and a third disconnector, wherein the disconnector is installed on the monitoring device body; The electrical principle structure inside the monitoring device body is as follows: The A-phase connection point is connected to the C-phase connection point through the first nonlinear resistor, the A-phase connection point is grounded through the second nonlinear resistor, the A-phase connection point is connected to the B-phase connection point through the third nonlinear resistor, the B-phase connection point is grounded through the fourth nonlinear resistor, the B-phase connection point is connected to the C-phase connection point through the fifth nonlinear resistor, and the C-phase connection point is grounded through the sixth nonlinear resistor; the first to sixth nonlinear resistors can be high-energy capacity valve plates The first disconnector is connected to the A phase connection point, the second disconnector is connected to the B phase connection point, and the third disconnector is connected to the C phase connection point; The current signals of the first disconnector, the second disconnector and the third disconnector are respectively collected through three current sensors (high-precision current sensors).

[0024] The nonlinear resistor can be a zinc oxide valve sheet or a zinc oxide resistor. Using a large-capacity independent nonlinear zinc oxide resistor sheet, each zinc oxide component operates independently without interfering with each other, achieving complete phase-to-phase and phase-to-ground protection. The action value of the device must be matched with the insulation of the protected equipment to form an overall protection system.

[0025] The capacity of the zinc oxide resistor can be set according to actual needs. The capacity refers to its flow capacity under specific conditions, usually expressed in amperes (A) or kiloamperes (KA). For example, the diameter of the valve plate used in low-voltage circuits is generally controlled at around 14-20mm, and the maximum flow capacity is generally between 60-70KA.

[0026] The six-column composite full-phase voltage-limiting monitoring device is composed of three sets of delta-connected and three sets of star-connected piezoresistors (zinc oxide valve plates, i.e., nonlinear resistors), three sets of phase-to-phase protection, and three sets of phase-to-ground protection, which operate independently without interfering with each other. It fully suppresses various overvoltages between phases and between phases and ground of the system (including lightning overvoltage, atmospheric overvoltage, operating overvoltage, and system transient overvoltage, etc.). The protection performance is more reliable and safer than that of the conventional four-star overvoltage protector.

[0027] In a possible implementation, the disconnector includes a copper link wire, an inner cylinder, quartz sand, a disconnect wire, an outer cylinder, and a conductive link rod, wherein the inner cylinder is wound with a disconnect wire, one end of the disconnect wire is connected to the conductive link rod, and the other end of the disconnect wire is connected to the copper link wire, the outer cylinder is sheathed on the outer side of the inner cylinder, and the gap between the inner cylinder and the outer cylinder is filled with quartz sand. Figure 6 As shown, the shape of the detached wire is a copper wire formed by connecting octagonal copper sheets.

[0028] In a possible implementation, the disconnector also includes a silicone rubber sheath, a high-voltage cable, and a wiring copper nose, wherein the silicone rubber sheath is arranged on the outside of the outer cylinder, the copper link wire is connected to the first end of the high-voltage cable, and the second end of the high-voltage cable is connected to the wiring copper nose; the wiring copper nose is connected to the protected system.

[0029] In a possible implementation, when overvoltage occurs in the power system to which the six-column composite full-phase voltage limiting monitoring device is connected, the overvoltage is absorbed by a nonlinear resistor.

[0030] In a possible implementation, the disconnector is used to automatically fuse the disconnect wire when a nonlinear resistor fails.

[0031] In one possible implementation, the device is also connected to a processor and a display screen, the processor is used to process the current data of the nonlinear resistor, and the display screen is used to display the fault phase sequence, time, and leakage current value; the processor monitors the leakage current values ​​between phases and between phases and ground, and displays the degradation process of the nonlinear resistor in three levels, 0mA-500mA is the first level, which is the normal range, 500mA-1000mA is the second level, indicating that the valve plate is slightly degraded, and greater than 1001mA is the third level, indicating that the valve plate is severely degraded.

[0032] Table 1 is the experimental data of the six-column composite protector ; The monitoring device can be used for overvoltage protectors of motors, generators, transformers, busbars, switches, capacitors and other equipment. The various types of protectors listed in the table have the same overvoltage protection level between phases and relative to ground.

[0033] Large flow rate, 2ms square wave impulse current is not less than 1200A, with better voltage limiting effect, stronger tolerance and longer service life. It adopts non-linear resistor, which has the advantages of fast action, flat volt-ampere characteristic, low residual voltage, stable performance, convenient assembly and maintenance. The discharge voltage value under various impulse voltage waveforms is equal, not affected by the overvoltage waveform, the overvoltage protection value is accurate, and the protection performance is excellent. It adopts a gapless fully sealed structure, and the phase-to-phase and phase-to-ground protection units are composed of independent whole gapless metal zinc oxide elements, which can greatly reduce the phase-to-phase overvoltage. Compared with conventional lightning arresters, the phase-to-phase overvoltage is reduced by 60-70%, and the protection reliability is greatly improved.

[0034] The epoxy resin internal integral sealing and glue filling process is adopted, so the valve plate is not easily affected by moisture and oxidation, making the action value more stable and reliable. With the function of automatic disengagement from faults, the device is maintenance-free, and at the same time, the tedious regular inspection work is eliminated, which solves the concerns of engineering and technical personnel about the safe operation of the equipment. It has the function of phase-to-phase and phase-to-ground overvoltage protection, which has a good protective effect on the internal overvoltage and external overvoltage of the system. The degradation process of the zinc oxide valve plate of the six-column composite full-phase voltage limiting monitoring device is realized throughout the life cycle, and the self-disengagement state of the overvoltage protection zone is monitored throughout the life cycle. All data can be sent to the background through 485 communication; the full life cycle monitoring solves the tedious related preventive tests of the overvoltage protector every year, and can effectively test the leakage current of the zinc oxide valve plate, and withdraw the unqualified or potential safety devices in advance, avoiding the occurrence of serious problems (such as explosions).

[0035] Six-axis robot assembly is adopted: the valve plates are stacked accurately without deviation, ensuring that each zinc oxide valve plate is completely overlapped, guaranteeing the flow cross-sectional area of ​​the valve plate and ensuring that the zinc oxide valve plate is evenly stressed; an automatic boost test system is adopted, which is not affected by external factors, with accurate data, high consistency and stable product characteristics.

[0036] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A six-column composite full-phase voltage limiting monitoring device, characterized in that: The device comprises: a monitoring device body, a first disconnector, a second disconnector, and a third disconnector, wherein the disconnector is mounted on the monitoring device body; The electrical principle structure inside the monitoring device body is as follows: The A-phase connection point is connected to the C-phase connection point through a first nonlinear resistor, the A-phase connection point is grounded through a second nonlinear resistor, the A-phase connection point is connected to the B-phase connection point through a third nonlinear resistor, the B-phase connection point is grounded through a fourth nonlinear resistor, the B-phase connection point is connected to the C-phase connection point through a fifth nonlinear resistor, and the C-phase connection point is grounded through a sixth nonlinear resistor; The first disconnector is connected to the A phase connection point, the second disconnector is connected to the B phase connection point, and the third disconnector is connected to the C phase connection point; The current signals of the first disconnector, the second disconnector and the third disconnector are respectively collected by three current sensors.

2. A six-column composite full-phase voltage limiting monitoring device according to claim 1, characterized in that: The disconnector includes a copper link wire, an inner cylinder, quartz sand, a disconnect wire, an outer cylinder, and a conductive link rod, wherein the inner cylinder is wound with a disconnect wire, one end of the disconnect wire is connected to the conductive link rod, and the other end of the disconnect wire is connected to the copper link wire, the outer cylinder is sheathed on the outside of the inner cylinder, and the gap between the inner cylinder and the outer cylinder is filled with quartz sand.

3. A six-column composite full-phase voltage limiting monitoring device according to claim 2, characterized in that: The disconnector also includes a silicone rubber sheath, a high-voltage cable, and a wiring copper nose, wherein the silicone rubber sheath is arranged outside the outer cylinder, the copper link wire is connected to the first end of the high-voltage cable, and the second end of the high-voltage cable is connected to the wiring copper nose; the wiring copper nose is connected to the protected system.

4. A six-column composite full-phase voltage limiting monitoring device according to claim 3, characterized in that: When overvoltage occurs in the power system to which the six-column composite full-phase voltage limiting monitoring device is connected, the overvoltage is absorbed by nonlinear resistors.

5. The six-column composite full-phase voltage limiting monitoring device according to claim 3, characterized in that: The disconnector is used to automatically fuse the disconnect wire when a nonlinear resistor fails.

6. A six-column composite full-phase voltage limiting monitoring device according to claim 3, characterized in that: The device is also connected to a processor and a display screen, the processor is used to process the current data of the nonlinear resistor, and the display screen is used to display the fault phase sequence, time, and leakage current value; The processor monitors the leakage current values ​​between phases and between phases and ground, and displays the degradation process of the nonlinear resistor in three levels. 0mA-500mA is the first level, which is the normal range, 500mA-1000mA is the second level, indicating that the valve plate is slightly degraded, and greater than 1001mA is the third level, indicating that the valve plate is severely degraded.

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