AU2021101553A4

AU2021101553A4 - Integrated fault isolation apparatus for transmission line

Info

Publication number: AU2021101553A4
Application number: AU2021101553A
Authority: AU
Inventors: Chengkuan SHEN; Zhiyin Sun; Xinhong Zhang
Original assignee: Strong Power Electric Co Ltd
Current assignee: Strong Power Electric Co Ltd
Priority date: 2021-03-26
Filing date: 2021-03-26
Publication date: 2021-05-20
Anticipated expiration: 2029-03-26

Abstract

The present disclosure provides an integrated fault isolation apparatus for a transmission line, including vacuum circuit breakers, a YDJ controller, and electrical sensors. There are three vacuum circuit breakers that are disposed on a housing and are connected to three-phase lines A, B, and C respectively. The electrical sensors include an electronic voltage sensor, an electronic current sensor, and a capacitive energy acquiring sensor, and the three sensors are integrated in bodies of the vacuum circuit breakers. The capacitive energy acquiring sensor is disposed on an energy acquiring unit, and the vacuum circuit breaker, the electronic voltage sensor, the electronic current sensor, the capacitive energy acquiring sensor, and the energy acquiring unit each are connected to the YDJ controller by using a circular connector and a cable. There are two energy acquiring units, and each energy acquiring unit is disposed between two vacuum circuit breakers. In the present disclosure, the sensor and a power acquiring apparatus are integrated on the vacuum circuit breaker to implement an integrated operation of the vacuum circuit breaker. This avoids interface, scalability, installation and commissioning, responsibility division, and other problems, and improves overall reliability of a device. FIGURES 1/2 7 3 FIG.1 APZ AP, asl BPz BPI cs OS2 6OSI FIG. 2 2/2 A B C C1 C3 C1 C3 C1 C C2 C a b n(dn)da c FIG. 3 o o 0 0 o c C 0 Protect 0: 0)Operat seune2 : Cls rp 4 FIG. 4

Description

FIGURES 1/2

7 3

FIG.1

APZ AP,

asl BPz BPI

cs OS2 6OSI FIG. 2

2/2

A B C

C1 C3 C1 C3 C1 C

C2 C

a b n(dn)da c FIG. 3

0 0 o c C 0

o o Protect 0: 0)Operat

:Cls rp seune2 4

FIG. 4

INTEGRATED FAULT ISOLATION APPARATUS FOR TRANSMISSION LINE

TECHNICAL FIELD The present disclosure relates to the field of power transmission and transformation, and in particular, to an integrated fault isolation apparatus for a transmission line.

BACKGROUND Construction and renovation of a distribution network are important parts of construction of a smart grid and energy transition, and play a key role in national economic construction and Internet of Energy (IoE) development at present and in the future. Primary and secondary integration is an inevitable way and an effective means to improve distribution devices and technologies, and also is an important symbol showing achievements made in construction of a smart distribution network in China. With the development of the smart grid, a primary device needs to be upgraded to a smart power device, and a secondary device needs to be upgraded to a smart control unit. Informatization, intelligentization, and integration are the development trend of a current distribution system. An existing fault isolation apparatus still uses a split sensor to collect information of a transmission line, and acquires power with a split voltage transformer. In addition, the existing fault isolation apparatus transmits data in a wired manner, and this reduces a degree of insulation between devices. The split structure increases a volume of a device, and results in heavy mass, making it inconvenient to perform subsequent transportation, installation, and maintenance.

SUMMARY To overcome disadvantages in the prior art, the present disclosure provides an integrated fault isolation apparatus for a transmission line. In the present disclosure, a sensor and a power acquiring apparatus are integrated on a vacuum circuit breaker to implement an integrated operation of the vacuum circuit breaker. This avoids interface, scalability, installation and commissioning, responsibility division, and other problems. According to the technical solutions of the present disclosure, an integrated fault isolation apparatus for a transmission line includes vacuum circuit breakers, a YDJ controller, and electrical sensors. There are three vacuum circuit breakers that are disposed on a housing and are connected to three-phase lines A, B, and C respectively. The electrical sensors include an electronic voltage sensor, an electronic current sensor, and a capacitive energy acquiring sensor, and the three sensors are integrated in bodies of the vacuum circuit breakers. The capacitive energy acquiring sensor is disposed on an energy acquiring unit, and the vacuum circuit breaker, the electronic voltage sensor, the electronic current sensor, the capacitive energy acquiring sensor, and the energy acquiring unit each are connected to the YDJ controller by using a circular connector and a cable. There are two energy acquiring units, and each energy acquiring unit is disposed between two vacuum circuit breakers. One end of the energy acquiring unit is connected to the vacuum circuit breaker by using a transformer, and the other end of the energy acquiring unit is disposed on the housing. Further, the housing is provided with a manual tripping/closing apparatus, a manual energy storage apparatus, a tripping/closing indication gauge, and the circular connector. Further, the three vacuum circuit breakers each have one external zero-sequence current transformer (CT) and two external single-phase CTs, the electronic current sensor is made based on a principle of a low-power current transformer (LPCT), and the electronic voltage sensor is made based on a principle of capacitive voltage dividing and molded through vacuum pouring by using epoxy resin. Further, the energy acquiring unit is an external potential transformer (PT), and provides a power supply and a voltage signal for operations performed by the YDJ controller and the vacuum circuit breaker. The external PT uses a high-voltage ceramic capacitor, the transformer, and a power control board to acquire energy. The high-voltage ceramic capacitor is molded through pouring by using the epoxy resin, and the transformer is integrated in the vacuum circuit breaker. Further, the vacuum circuit breaker is provided therein with a temperature sensor that is insulated by air and used for detecting operating temperatures of high-voltage dynamic and static contacts, the temperature sensor performs high-voltage isolation and signal transmission by using an electronic sensing technology and a wireless communications technology, and a 433 Hz radio frequency communications technology is used as the wireless communications technology. Further, a medium-voltage carrier communications coupler inside the vacuum circuit breaker performs carrier communication or radio frequency identification (RFID) communication by using a carrier machine. The present disclosure has the following beneficial effects: 1. In the present disclosure, the sensor and the power acquiring apparatus are integrated on the vacuum circuit breaker to implement an integrated operation of the vacuum circuit breaker. This avoids interface, scalability, installation and commissioning, responsibility division, and other problems, improves overall reliability and economical efficiency of a device, realizes intelligent operation and maintenance, fault prediction, and operating status monitoring and life cycle management of a line device, reduces intensity of patrolling, power outages, electric shocks, and fire accidents, and supports accurate fault locating and fast power supply restoration. 2. In the present disclosure, the electronic current sensor is made based on the principle of the LPCT. An output analog small-voltage signal is directly input to a secondary device without secondary conversion. The electronic current sensor is characterized by a small volume, light weight, wide frequency response, no saturation phenomenon, good anti-electromagnetic interference performance, and reliable insulation. 3. In the present disclosure, the electronic voltage sensor follows the principle of capacitive voltage dividing, and is made through vacuum pouring by using the epoxy resin. The electronic voltage sensor outputs a standard small signal that can be directly input to a protection apparatus or a measuring module through analog to digital (A/D) conversion without secondary conversion. The electronic voltage sensor does not contain iron cores, is free from saturation, and has a wide frequency range, a large measurement range, good linearity, and a strong anti-interference ability. This enables the protection apparatus to operate reliably when a system fault occurs. 4. In the present disclosure, the energy acquiring unit acquires the energy by using the high voltage ceramic capacitor, the transformer, and the power control board. The high-voltage ceramic capacitor is molded through pouring by using the epoxy resin. The transformer is integrated in a switch, and outputs a safe voltage of 100 V to a secondary apparatus for power acquiring. 5. In the present disclosure, the temperature sensor performs high-voltage isolation and signal transmission by using the electronic sensing technology and the wireless communications technology, is insulated by air, and monitors the operating temperatures of the high-voltage dynamic and static contacts, to measure a temperature of a high-voltage device in real time. The temperature sensor can be powered by using a battery or a CT, and has low power consumption. A 433 Hz radio-frequency communications technology is used as the wireless communications technology. 6. In the present disclosure, the switch in the vacuum circuit breaker is integrated with the medium-voltage carrier communications coupler that can be directly connected to a carrier machine for carrier communication. An advanced lightning protection technology is adopted to effectively ensure safety of the device. Communication in a region not covered by 4G communication is realized.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic structural diagram of an integrated fault isolation apparatus for a transmission line; FIG. 2 is a circuit diagram of an electronic current sensor; FIG. 3 is a circuit diagram of an electronic voltage sensor; and FIG. 4 is a schematic structural diagram of an operation panel of a YDJ controller.

DETAILED DESCRIPTION For the embodiments, refer to FIG. 1, FIG. 2, FIG. 3, and FIG. 4. In the figures, 1 represents a vacuum circuit breaker, 2 represents an electrical sensor, 3 represents an energy acquiring unit, 4 represents a circular connector, 5 represents a housing, 6 represents a manual tripping/closing apparatus, 7 represents a manual energy storage apparatus, and 8 represents a tripping/closing indication gauge. An integrated fault isolation apparatus for a transmission line includes vacuum circuit breakers 1, a YDJ controller, and electrical sensors 2. The sensor and a power acquiring apparatus are integrated on the vacuum circuit breaker to implement an integrated operation of the vacuum circuit breaker. This avoids interface, scalability, installation and commissioning, responsibility division, and other problems, improves overall reliability and economical efficiency of a device, realizes intelligent operation and maintenance, fault prediction, and operating status monitoring and life cycle management of a line device, reduces intensity of patrolling, power outages, electric shocks, and fire accidents, and supports accurate fault locating and fast power supply restoration. The present disclosure is described in detail below with reference to the accompanying drawings and embodiments. There are three vacuum circuit breakers 1 that are disposed on a housing 5 and are connected to three-phase lines A, B, and C respectively. The electrical sensors 2 include an electronic voltage sensor, an electronic current sensor, and a capacitive energy acquiring sensor, and the three sensors are integrated in bodies of the vacuum circuit breakers 1. The capacitive energy acquiring sensor is disposed on an energy acquiring unit 3, and the vacuum circuit breaker 1, the electronic voltage sensor, the electronic current sensor, the capacitive energy acquiring sensor, and the energy acquiring unit 3 each are connected to the YDJ controller by using a circular connector 4 and a cable. There are two energy acquiring units 3, and each energy acquiring unit 3 is disposed between two vacuum circuit breakers 1. One end of the energy acquiring unit 3 is connected to the vacuum circuit breaker 1 by using a transformer, and the other end of the energy acquiring unit 3 is disposed on the housing 5. The housing 5 is provided with a manual tripping/closing apparatus 6, a manual energy storage apparatus 7, a tripping/closing indication gauge 8, and the circular connector. The electronic current sensor is made based on a principle of an LPCT. The electronic voltage sensor is made based on a principle of capacitive voltage dividing and molded through vacuum pouring by using epoxy resin. The three vacuum circuit breakers each have one external zero-sequence CT and two external single-phase CTs. For the zero-sequence CT, a transformation ratio is 20/1, there is a linear relationship in a range from 0.1 A to 5 A (primary current), rated load is1 Q, a transformation ratio error under the rated load should be less than 3%, a primary zero-sequence current is 400 A, a valid value of a secondary output current is not less than 5 A, and rated short-time withstand currents are 16 kA, 20 kA, 25 kA, and last 4 s. For the single-phase CT, a transformation ratio is 600/5 (or specified by a user), rated load is 10 Q, precision is10P20, and rated short-time withstand currents are 16 kA and 20 kA, and last 4 s. The electronic current sensor is made based on the principle of the LPCT. The electronic voltage sensor is made based on the principle of capacitive voltage dividing and molded through vacuum pouring by using the epoxy resin. The energy acquiring unit is an external PT (with a transformation ratio of 10000 V/220 V, a capacity of 300 VA, and a precision of 3P), and provides a power supply and a voltage signal for operations performed by the YDJ controller and the vacuum circuit breaker. The external PT uses a high-voltage ceramic capacitor, the transformer, and a power control board to acquire energy. The high-voltage ceramic capacitor is molded through pouring by using the epoxy resin, and the transformer is integrated in the vacuum circuit breaker. A medium-voltage carrier communications coupler inside the vacuum circuit breaker performs carrier communication or RFID communication by using a carrier machine. An RFID technology is a communications technology, and is commonly known as an electronic tag. Radio signals can be used to identify a specific target and read/write related data, without mechanical or optical contact between an identification system and the specific target. A monitoring unit for a medium-voltage overhead line grid in the YDJ controller cooperates with a pole mounted switch to realize remote control and automatic management. A case of the YDJ controller is made from outdoor epoxy resin. An operation panel is vertical downward. The operation panel has polycarbonate (PC) membranes for protection, and has a GSM short messaging service (SMS) function. As shown in FIG. 4, D represents various status light emitting diode (LED) indicators, @ represents manual closing/tripping keys, @ represents cautions, @) represents function keys for liquid crystal operations, @ represents "liquid crystal" in Chinese, @ represents a circular socket for a control cable, ( represents a circular socket for a power cable, @ represents a grounding bolt, and @ represents a position for installing a nameplate/SIM card. A power supply of the YDJ controller is from a high-voltage transformer. A rated voltage of the power supply is AC220 V, with a frequency of 50 Hz. After the power supply is connected to the circular socket, the YDJ controller automatically enters an operating state, and the YDJ controller has a built-in 2A fuse. The YDJ controller is charged by using a stabilized voltage, to ensure that a voltage of an energy storage capacitor is within DC220 V 3V, and charging time of THE capacitor is < 0.5 s. An energy storage motor of the pole mounted switch is powered by using a PT voltage, and the power supply from the energy storage motor is supplied to the pole mounted switch after passing through the YDJ controller. The YDJ controller has its own energy storage capacitor that provides closing/tripping energy. To avoid impact of line voltage fluctuation on a closing/tripping operation, an output voltage of a closing/tripping control circuit is DC220 V. When a line voltage drops suddenly, the capacitor allows the YDJ controller to operate no less than 6 s, and supports reclosing once. Information of a transmission line and the operating temperatures of the high-voltage dynamic and static contacts in the vacuum circuit breaker are monitored by using the voltage, current, and temperature sensors, and are transmitted to the YDJ controller for analysis, to determine whether there is a fault, and to control the vacuum circuit breaker to perform the tripping/closing operation. In addition, detection information is externally transmitted by using the wireless communications technology. When a single-phase grounding fault occurs on a branch line, the vacuum circuit breaker automatically trips, and users of a substation and other branches of a feeder line are not affected by the fault. An inter-phase short-circuit fault is automatically isolated. When the inter-phase short circuit fault occurs on a branch line, the vacuum circuit breaker trips before an outgoing line protection switch of the substation, to automatically isolate the faulty line, so that users of other branches of the feeder line are not affected. Fast fault locating is supported. When a fault on a branch line causes the vacuum circuit breaker to perform a protection operation, only a corresponding user undergoes a power outage, and actively reports fault information to a power company. The power company can quickly arrange personnel for troubleshooting. If the vacuum circuit breaker is equipped with a communications module, the fault information is actively reported to a power management center. User load is monitored. The vacuum circuit breaker may be equipped with a wired or wireless communication accessory to transmit monitoring data to the power management center, thereby realizing remote real-time data monitoring for the user load. A remote operation function is provided. A user can trip the vacuum circuit breaker by using an SMS message, a computer, or an on-site manual operation (by using the manual tripping/closing apparatus and the manual energy storage apparatus). The above description is only a preferred embodiment of the present disclosure and is not intended to limit the present disclosure in any form. Any simple modifications and equivalent changes and modifications made to the above embodiment according to the technical essence of the present disclosure are within the scope of the technical solution of the present disclosure.

Claims

What is claimed is: 1. An integrated fault isolation apparatus for a transmission line, comprising vacuum circuit breakers, a YDJ controller, and electrical sensors, wherein there are three vacuum circuit breakers that are disposed on a housing and are connected to three-phase lines A, B, and C respectively; the electrical sensors comprise an electronic voltage sensor, an electronic current sensor, and a capacitive energy acquiring sensor, and the three sensors are integrated in bodies of the vacuum circuit breakers; the capacitive energy acquiring sensor is disposed on an energy acquiring unit, and the vacuum circuit breaker, the electronic voltage sensor, the electronic current sensor, the capacitive energy acquiring sensor, and the energy acquiring unit each are connected to the YDJ controller by using a circular connector and a cable; there are two energy acquiring units, and each energy acquiring unit is disposed between two vacuum circuit breakers; and one end of the energy acquiring unit is connected to the vacuum circuit breaker by using a transformer, and the other end of the energy acquiring unit is disposed on the housing.
2. The integrated fault isolation apparatus for a transmission line according to claim 1, wherein the housing is provided with a manual tripping/closing apparatus, a manual energy storage apparatus, a tripping/closing indication gauge, and the circular connector.
3. The integrated fault isolation apparatus for a transmission line according to claim 1, wherein the three vacuum circuit breakers each have one external zero-sequence current transformer (CT) and two external single-phase CTs, the electronic current sensor is made based on a principle of a low-power current transformer (LPCT), and the electronic voltage sensor is made based on a principle of capacitive voltage dividing and molded through vacuum pouring by using epoxy resin.
4. The integrated fault isolation apparatus for a transmission line according to claim 1, wherein the energy acquiring unit is an external potential transformer (PT), and provides a power supply and a voltage signal for operations performed by the YDJ controller and the vacuum circuit breaker, the external PT uses a high-voltage ceramic capacitor, the transformer, and a power control board to acquire energy, the high-voltage ceramic capacitor is molded through pouring by using epoxy resin, and the transformer is integrated in the vacuum circuit breaker.
5. The integrated fault isolation apparatus for a transmission line according to claim 1, wherein the vacuum circuit breaker is provided therein with a temperature sensor that is insulated by air and used for detecting operating temperatures of high-voltage dynamic and static contacts, the temperature sensor performs high-voltage isolation and signal transmission by using an electronic sensing technology and a wireless communications technology, and a 433 Hz radio-frequency communications technology is used as the wireless communications technology; wherein a medium-voltage carrier communications coupler inside the vacuum circuit breaker performs carrier communication or radio frequency identification (RFID) communication by using a carrier machine.

FIGURES 26 Mar 2021

1/2 2021101553

FIG. 1

FIG. 2