WO2021042601A1 - 一种海底充油电缆直流耐压试验的放电装置及放电方法 - Google Patents

一种海底充油电缆直流耐压试验的放电装置及放电方法 Download PDF

Info

Publication number
WO2021042601A1
WO2021042601A1 PCT/CN2019/122531 CN2019122531W WO2021042601A1 WO 2021042601 A1 WO2021042601 A1 WO 2021042601A1 CN 2019122531 W CN2019122531 W CN 2019122531W WO 2021042601 A1 WO2021042601 A1 WO 2021042601A1
Authority
WO
WIPO (PCT)
Prior art keywords
discharge
voltage
test
car
resistor
Prior art date
Application number
PCT/CN2019/122531
Other languages
English (en)
French (fr)
Inventor
罗朋振
黎建平
王竣
韦晓星
张潮
曾航
梁晨
罗小彬
黄大为
王言
杨锡清
姜克如
黄聪
Original Assignee
中国南方电网有限责任公司超高压输电公司检修试验中心
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 中国南方电网有限责任公司超高压输电公司检修试验中心 filed Critical 中国南方电网有限责任公司超高压输电公司检修试验中心
Publication of WO2021042601A1 publication Critical patent/WO2021042601A1/zh

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
    • G01R31/1227—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials
    • G01R31/1263—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials of solid or fluid materials, e.g. insulation films, bulk material; of semiconductors or LV electronic components or parts; of cable, line or wire insulation
    • G01R31/1272—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials of solid or fluid materials, e.g. insulation films, bulk material; of semiconductors or LV electronic components or parts; of cable, line or wire insulation of cable, line or wire insulation, e.g. using partial discharge measurements
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
    • H01T19/00—Devices providing for corona discharge
    • H01T19/02—Corona rings
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
    • H01T19/00—Devices providing for corona discharge
    • H01T19/04—Devices providing for corona discharge having pointed electrodes

Definitions

  • the invention relates to the technical field of submarine cable DC withstand voltage test, in particular to a discharge device and discharge method for submarine oil-filled cable DC withstand voltage test.
  • a discharge device for the DC withstand voltage test of a submarine oil-filled cable which includes a discharge car, a tie rod, a discharge resistor, a transmission device and a high-voltage wire;
  • the discharge car includes a discharge tip, a universal ball, a pulley and a car body, and the pulley is installed on the side of the car body ,
  • rolling connection with the pull rod the universal ball is rotatably installed on the upper end of the car body, the discharge tip is fixed on the universal ball, and the transmission device is used to drive the discharge car to slide along the pull rod to make the discharge tip contact or separate from the equipment to be discharged.
  • the transmission device includes a miniature electric hoist, a discharge resistor and a draw rope.
  • One end of the draw rope is connected to the electric discharge car, and the other end is connected to the miniature electric hoist after bypassing the fixed pulley.
  • the miniature electric hoist lifts the discharge trolley by pulling the rope so that the discharge tip contacts with the equipment to be discharged for discharge.
  • the pull rod and the pull rope are made of insulating materials.
  • the discharge resistor includes a resistor, a base and a grounding pole, the resistor is vertically fixed on the base, the grounding pole is connected to the lower end of the resistor, and the inside of the resistor is filled with transformer oil.
  • the resistor is filled with transformer oil, which has good heat dissipation effect and can withstand larger discharge current and long discharge time.
  • a voltage equalization cover is also provided at the upper end of the discharge resistor. Since the discharge car and the discharge resistor are connected through a high-voltage wire, and a voltage equalization cover is provided, the voltage equalization effect can be achieved during the discharge process.
  • a take-up reel is further provided on the pressure equalization cover, and the high-voltage wire is at least partially wound on the take-up reel.
  • the high-voltage wire can be quickly recovered through the take-up reel to improve the discharge efficiency.
  • a discharge method for the DC withstand voltage test of a submarine oil-filled cable includes the following steps:
  • Step 1 Before the start of the DC withstand voltage test, place the DC high voltage generator and the voltage divider. In order to improve the reliability of the test system, two voltage dividers are placed during the test, and the two voltage dividers Parallel connection
  • Step 2 Fix the tie rods: hang two nylon tie rods on the special lifting ring for the equalizing ring of the voltage divider, and fix the bottom of the tie rod on the special lifting ring for the support leg of the voltage divider. Tighten the tie rods to make the distance between the tie rods uniform;
  • Step 3 Fix the draw rope: The draw rope passes through the fixed pulley, and the fixed pulley is fixed to the special hoisting ring of the pressure divider, and the fixed pulley is located in the middle of the two pull rods;
  • Step 4 Fixing the miniature electric hoist: Fix the miniature electric hoist to the support leg of the voltage divider, and fix a section of the draw rope to the winding shaft of the miniature electric hoist;
  • Step 5 Install the electric car: insert the pull rod between the pulleys of the electric car, make the electric car slide along the lever, install the discharge tip on the universal ball of the electric car, and tie the other end of the rope to the electric car, the discharge tip should be Towards the equalizing ring of the voltage divider;
  • Step 6 Install the discharge resistor and the voltage equalization cover: fix the resistor to the base, connect the grounding pole at the bottom, install the voltage equalization cover on the top, and move the discharge resistor to the side of the voltage divider.
  • the grounding pole is reliably grounded by a high-voltage wire. Reliably connect the discharge car to the discharge resistor.
  • Step 7 Function test: Before the test officially starts, the function test of the discharge device should be carried out, the power supply of the micro electric hoist should be connected, and the discharge car should slowly move to the voltage divider ring with the high voltage wire when the up button is pressed. When reaching the top, the discharge tip is in reliable contact with the equalizing ring of the voltage divider. When the down button is pressed, the discharge car should slowly move to the support leg of the voltage divider with the high voltage wire. After the function test is completed, the discharge car stays near the support leg of the voltage divider. , The high-voltage wire is retracted through the take-up reel on the pressure equalizing cover;
  • Step 8 Use the stepwise pressure method to increase the DC high voltage applied to the submarine cable to 75% of the factory test value and keep it for 15 minutes;
  • Step 9 After the pressure is over, immediately disconnect the switch on the side of the power supply, and use the insulation resistance of the test equipment and the cable itself to discharge naturally to reduce the DC test voltage to below 300kV;
  • Step 10 Control the discharge trolley to slowly rise and approach the voltage divider equalizing ring through the micro electric hoist, so that a discharge channel is formed between the discharge tip and the equalizing ring, hold for 10s, and then lower the discharge trolley until the discharge passage is extinguished, and so on. 3 times, at last, make the discharge car slowly approach the voltage divider equalizing ring again, and press the discharge tip against the voltage equalizing ring of the voltage divider until the discharge ends, the discharge process should be more than 5 minutes, and the discharge current should not exceed 100mA;
  • Step 11 When the discharge device reduces the voltage of the submarine cable below 1kV, ground the submarine cable with a grounding wire.
  • the cross-section of the grounding wire should not be less than 25mm 2 and the grounding time should not be less than 24 hours to complete the entire discharge process.
  • the present invention has the following beneficial effects:
  • the discharge device of the present invention discharges the equipment after the withstand voltage test through a discharge resistor, can quickly release a large amount of accumulated charges, greatly shorten the discharge time, and improve the efficiency of the withstand voltage test.
  • the discharge device of the present invention can control the discharge vehicle to contact the tested equipment by remotely controlling the miniature electric hoist, which reduces the risk of electric shock for test personnel and greatly improves the safety of discharge operation.
  • the discharge device of the present invention has simple structure, small size, high reliability, convenient transportation and on-site assembly, and simple maintenance in the later period, which greatly reduces the use cost of the electric discharge vehicle.
  • the discharge method of the present invention uses two voltage dividers in parallel to reduce the time constant RC value of the discharge circuit, so that the natural discharge time is greatly shortened, and it is clear that the insulation of the test equipment and the cable itself is used.
  • the resistance discharges naturally.
  • the discharge device is used for rapid discharge.
  • the detailed discharge operation steps also further ensure the safety of the test personnel, the equipment under test and the test equipment.
  • Figure 1 is a schematic diagram of the overall structure of the electric discharge vehicle of the present invention.
  • Figure 2 is a schematic diagram of the structure of the electric discharge car of the present invention.
  • FIG. 3 is a schematic diagram of the structure of the discharge resistor of the present invention.
  • Figure 4 is a schematic diagram of the structure of the pressure equalizing cover of the present invention.
  • Figure 5 is a schematic diagram of the matching of the voltage equalization cover and the discharge resistor of the present invention.
  • FIG. 6 is a schematic diagram of the positions of the voltage divider and the DC high-voltage generator during the DC withstand voltage test and discharge of the submarine cable of the present invention
  • a discharge device for the DC withstand voltage test of a submarine oil-filled cable includes a discharge car 1, a voltage equalization cover 2, a draw rod 3, a miniature electric hoist 4, a discharge resistor 5, a draw rope 6, a fixed pulley 7 and High-voltage wire 22.
  • the connection relationship between the submarine cable, the voltage divider and the DC high voltage generator is shown in Figure 6.
  • two voltage dividers 8 were placed during the test.
  • the voltage divider 8 is respectively placed between the terminal heads 30 of the three-phase submarine cable.
  • the voltage divider 8 and the DC high voltage generator 10 are connected by a current limiting resistor 9, and two voltage dividers 8 are connected in parallel.
  • the parallel connection of the two voltage dividers 8 can reduce the total resistance of the voltage divider 8 to about 1/2, and the discharge loop time constant RC can be effectively lower, so that the natural discharge time can be greatly shortened.
  • the fixed pulley 7 is installed at the bottom of the equalizing ring 81 of the voltage divider 8; the tie rod 3 is arranged obliquely, the lower end is fixed on the support leg 82 of the voltage divider 8, and the upper end is fixed on the special lifting ring of the equalizing ring 81 of the voltage divider 8. ;
  • the miniature electric hoist 4 is fixed on the support leg 82, and the discharge resistor 5 is placed on one side of the voltage divider 8.
  • the discharge car 1 is slidably mounted on the pull rod 3. One end of the pull rope 6 is connected to the discharge car 1, and the other end is connected to the mini electric hoist 4 after bypassing the fixed pulley 7.
  • the upper end of the discharge resistor 5 is connected to the discharge car 1 through a high-voltage wire 22, and the lower end Grounded.
  • the miniature electric hoist 4 can drive the electric discharge car 1 to move up and down along the pull rod 3 through the drawstring 6, and when the electric discharge car 1 contacts the equalizing ring 81, it can discharge.
  • the pull rod 3 and the pull rope 6 are made of insulating materials, such as nylon, which have good strength and insulation performance, and are the fixed track of the electric discharge car 1.
  • the mini electric hoist 4 is commercially available and has an emergency braking device. When an abnormality occurs during the discharge, the discharge car 1 can be stopped immediately, and the mini electric hoist 4 can be remotely controlled to ensure the safety of test personnel.
  • the electric discharge car 1 includes a discharge tip 11, a universal ball 12, a locking handle 13, a pulley 14, a rope hole 15 and a car body 16.
  • the car body 16 is a rectangular hollow structure formed by splicing two U-shaped plates. The two U-shaped plates are locked by the locking handle 13, and the side walls of the two U-shaped plates are provided with a plurality of pulleys 4, thus forming In the pulley block, there are two pull rods 3 which respectively pass through the middle of the two pulley blocks, so that the electric car 1 slides along the pull rod 3.
  • the universal ball 12 is rotatably connected to the fixing frame at one end of the car body 16 facing the voltage divider ring.
  • the discharge tip 11 is rod-shaped, one end is fixed on the universal ball 12, and the tip at the other end is used to contact the voltage divider equalizer. Pressure ring. Since the angle of the universal ball 12 can be flexibly adjusted, the position of the discharge tip 11 can be adjusted to adapt to different test conditions.
  • the rope hole 15 is used to bind the rope 6 and the high-voltage wire 22 can be directly tied to the car body 16.
  • the discharge resistor 5 is used to form a discharge channel to release a large amount of accumulated charges, and includes a resistor 51, a base 52 and a grounding pillar 53.
  • the base 52 is used to stably support the resistor 51
  • the resistor 51 is vertically fixed on the base 52
  • the grounding post 53 is connected to the lower end of the resistor 51.
  • the resistor 51 is filled with transformer oil, which has a good heat dissipation effect and can withstand a large discharge current and a long discharge time.
  • the resistance value of resistor 51 should conform to the calculation result of formula (1):
  • the margin coefficient in the calculation process is 1.5; R is the resistance value, in M ⁇ ; T is the continuous discharge time, in min; P is the discharge power, in W; U d is the DC withstand voltage value, in M ⁇ kV; C is the capacitance value of the tested cable to ground, in ⁇ F.
  • U d in this test is -750kV
  • the submarine cable-to-earth capacitance value is 7.49 ⁇ F
  • the discharge resistance value is 5M ⁇
  • the continuous discharge time is required to be no less than 6.2 hours
  • the rated discharge power should be no less than 102.6kW .
  • the voltage equalization cover 2 is used in conjunction with the discharge resistor 5 to perform a voltage equalization function during the discharge process, and it includes a voltage equalization cover body 23 and a take-up reel 21.
  • the pressure cover body 23 has a circular ring shape and can be sleeved on the upper end of the resistor 51, and the take-up reel 21 is rotatably connected to the pressure cover body 23.
  • the specific structure can be designed according to actual conditions.
  • One end of the high-voltage wire 22 is fixed on the take-up reel 21, usually wound on the rotating shaft of the take-up reel 21, pulled out during discharge, and the other end is connected to the discharging car 1. After the discharge is completed, pass the take-up reel 21 quickly The high-voltage wire 22 is recovered to improve the discharge efficiency.
  • the high-voltage wire 22 is strictly prohibited from falling to the ground or the base 52 of the discharge resistor 5.
  • the miniature electric hoist 4 is controlled by remote control, and the electric discharge car 1 is driven to move forward along the pull rod 3 by tightening the rope 6 until the discharge tip 11 of the electric discharge car 1 touches the equalizing ring of the voltage divider.
  • Step 1 Before the DC withstand voltage test, place the DC high voltage generator 10 and the voltage divider 8. In order to improve the reliability of the test system, two resistive voltage dividers 8 are placed during the test.
  • the voltage divider 8 is respectively placed between the three-phase submarine cable terminal heads 30, the voltage divider 8 and the DC high voltage generator 10 are connected by a current limiting resistor 9, and the two voltage dividers 8 are connected in parallel, and the two are divided
  • the parallel connection of the voltage divider 8 can reduce the total resistance of the voltage divider 8 to about 1/2 of the original value, and the discharge loop time constant RC can be effectively lower, so that the natural discharge time can be greatly shortened.
  • Step 2 Fix the tie rod 3: Hang two nylon tie rods 3 on the special lifting ring of the equalizing ring 81 of the voltage divider 8, keep the distance between the tie rods 3 100mm, and fix the other end on the voltage divider 8 with a turnbuckle hook. On the special lifting ring of the supporting leg 82, adjust the turnbuckle screw hook to tighten the nylon pull rod 3, so that the distance between the pull rods 3 is uniform, and it is convenient for the electric car 1 to slide.
  • Step 3 Fix the draw rope 6: The draw rope 6 passes through the fixed pulley 7, and the fixed pulley 7 is fixed to the special lifting ring of the pressure equalizing ring 81 (located in the middle of the auxiliary pull rod 3).
  • Step 4 Fix the miniature electric hoist 4: Fix the miniature electric hoist 4 to the supporting leg 82, the fixed position is about 500mm away from the pull rod 3, and fix one end of the pull rope 6 to the winding shaft of the miniature electric hoist 4.
  • Step 5 Fixing the electric car 1: loosen the locking handle 13 of the electric car 1, insert the pull rod 3 between the pulleys 14 of the electric car 1, buckle and tighten the locking handle 13, and then install the discharge tip 11 to On the universal ball 12 of the discharge car 1, the other end of the draw rope 6 is tied to the discharge car 1, and the discharge tip 11 should face the equalizing ring 81.
  • Step 6 Install the discharge resistor 5 and the voltage equalization cover 2:
  • the resistor 51 is fixed to the base 52, the bottom is connected to the grounding pole 53, and the voltage equalization cover 2 is installed on the top, the discharge resistor 5 is moved to the right side of the support leg 82, the grounding pole 53 is reliably grounded with a ground wire, and the discharge car 1 and the discharge resistor 5 are reliably connected through the high-voltage wire 22.
  • Step 7 Function test: Before the test officially starts, the function test of the discharge device should be carried out.
  • the micro electric hoist 4 is connected to the 220V AC power supply.
  • the up button When the up button is pressed, the discharge car 1 should slowly move to the equalizing ring with the high-voltage wire 22 81. When reaching the top, the discharge tip 11 and the equalizing ring 81 can be reliably contacted.
  • the down button When the down button is pressed, the discharge car 1 should slowly move to the support leg 82 with the high voltage wire 22. After the function test is completed, the discharge car 1 stays on the support leg 82 Nearby, the high-voltage wire 22 is wound around the recovery reel 21 again.
  • Step 8 Use the stepwise pressure method to increase the DC high voltage applied to the submarine cable to 75% of the factory test value and keep it for 15 minutes.
  • Step 9 After the pressure is over, immediately disconnect the switch on the side of the power supply, and use the test equipment and the insulation resistance of the submarine cable itself to discharge naturally to reduce the DC test voltage to less than 300kV.
  • Step 10 Use the miniature electric hoist 4 to slowly raise the discharge car 1 and approach the equalizing ring 81.
  • the equalizing ring 81 When approaching the equalizing ring 81 for the first time, when a discharge channel is formed between the discharge tip 11 and the equalizing ring 81, keep the original Position for 10s, then lower the height of the discharge car 1 until the discharge channel is extinguished; then make the discharge car 1 slowly approach the equalizing ring 81 for the second time, and maintain the original position for 10s when a discharge channel is formed between the discharge tip 11 and the equalizing ring 81 , And then lower the height of the discharge car 1 until the discharge channel is extinguished; for the third time, the discharge car 1 is slowly approached to the equalizing ring 81, when a discharge channel is formed between the discharge tip 11 and the equalizing ring 81, keep the original position for 10s, and then lower The height of the discharge car 1 until the discharge channel is extinguished; then, for the fourth time (the last time), the discharge car 1 is slowly
  • Step 11 When using the discharge device of the present invention to reduce the voltage of the tested cable below 1kV, a dedicated grounding wire should be used to ground the tested submarine cable (the cross-section of the dedicated grounding wire should not be less than 25mm 2 ), and a short circuit should be ensured
  • the grounding time is not less than 24 hours to complete the entire discharge process.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • General Physics & Mathematics (AREA)
  • Testing Relating To Insulation (AREA)

Abstract

一种海底充油电缆直流耐压试验的放电装置及放电方法。放电装置包括放电车、拉杆、放电电阻、传动装置和高压导线；放电车包括放电尖端、万向球、滑轮和车体，滑轮安装在车体侧面，且与拉杆滚动连接，万向球转动安装在车体上端，放电尖端固定在万向球上，传动装置用于驱动放电车沿拉杆滑动，以使放电尖端与待放电设备接触或者分离。能快速释放掉积累在被试设备本体上的残余电荷，有效提高了耐压试验的效率，确保了耐压试验的安全。

Description

一种海底充油电缆直流耐压试验的放电装置及放电方法 技术领域
本发明涉及海底电缆直流耐压试验技术领域，具体涉及一种海底充油电缆直流耐压试验的放电装置及放电方法。
背景技术
海底充油电缆投入运行时，需要对电缆进行直流耐压试验，该试验是考核电缆绝缘性能及其承受过电压能力的主要方法，并能够有效检测电缆的机械损伤、介质受潮等局部缺陷。但由于电缆的对地电容量相当大，在对海底充油电缆进行直流耐压试验后，电缆集聚了大量的电荷，仍保持有数百千伏的高压，因此采用人工放电是不安全的，若只利用试验设备本身进行自然放电，往往需要数小时以上，这直接导致试验效率低下，严重拖慢工程进度。而且现有的放电装置体积大、结构复杂、安装繁琐、控制回路故障率高，这直接导致其可靠性低，后期维护成本高。
针对以上问题，亟需研制一套体积小、结构简单、安装快捷、性能可靠的放电装置和科学安全的放电方法。
发明内容
为解决目前海底充油电缆直流耐压试验放电时间长、现有放电装置可靠性低、维护成本高的问题，提供一种海底充油电缆直流耐压试验的放电装置及放电方法。
为实现上述目的，本发明采用的技术方案是：
一种海底充油电缆直流耐压试验的放电装置，包括放电车、拉杆、放电电阻、传动装置和高压导线；放电车包括放电尖端、万向球、滑轮和车体，滑轮安装在车体侧面，且与拉杆滚动连接，万向球转动安装在车体上端，放电尖端固定在万向球上，传动装置用于驱动放电车沿拉杆滑动，以使放电尖端与待放电设备接触或者分离。
作为本发明的一种改进，所述的传动装置包括微型电动葫芦、放电电阻和拉绳，拉绳一端与放电车连接，另一端绕过定滑轮后与微型电动葫芦连接。微型电动葫芦通过拉绳提升放电车，使放电尖端与待放电设备接触进行放电。
作为本发明的一种改进，所述的拉杆和拉绳采用绝缘材料制成。
作为本发明的一种改进，所述的放电电阻包括电阻、底座和接地柱，电阻竖直固定在底 座上，接地柱连接在电阻下端，电阻内部充满变压器油。电阻内部充满变压器油，散热效果好，能承受住较大放电电流及长的放电时间。
作为本发明的一种改进，所述的放电电阻上端还设置有均压罩。由于放电车与放电电阻通过高压导线连接，设置均压罩，在放电过程中能起到均压作用。
作为本发明的一种改进，所述的均压罩上还设置有收线盘，所述的高压导线至少部分缠绕在收线盘上。通过收线盘能快速回收高压导线，提高放电效率。
一种海底充油电缆直流耐压试验的放电方法，包括如下步骤：
步骤一、直流耐压试验开始前，摆放好直流高压发生器与分压器的位置，为了提高试验系统的可靠性，试验过程中放置了两台分压器，且将两台分压器并联连接；
步骤二、固定拉杆：将两根尼龙拉杆挂到分压器均压环专用吊环上，拉杆底部则固定在分压器支撑腿专用吊环上，收紧拉杆，使拉杆间距均匀一致；
步骤三、固定拉绳：拉绳穿过定滑轮，定滑轮则固定到分压器均压环专用吊环上，定滑轮位于两根拉杆的中间；
步骤四、固定微型电动葫芦：把微型电动葫芦固定到分压器支撑腿上，并将拉绳的一段固定到微型电动葫芦的绕线轴上；
步骤五、安装放电车：把拉杆嵌在放电车的滑轮之间，使放电车沿拉杆滑动，把放电尖端安装到放电车的万向球上，拉绳另一端系住放电车，放电尖端应朝向分压器均压环；
步骤六、安装放电电阻和均压罩：电阻固定到底座上，底部连接好接地柱，顶部安装好均压罩，把放电电阻移动到分压器旁边，接地柱用地线可靠接地，通过高压导线将放电车与放电电阻可靠连接。
步骤七、功能测试：在试验正式开始前，应进行放电装置的功能测试，接通微型电动葫芦的电源，按上升键时放电车应带着高压导线缓缓移向分压器均压环，到顶部时放电尖端与分压器均压环可靠接触，按下降键时放电车应带着高压导线缓缓移向分压器支撑腿，功能测试完后放电车停留在分压器支撑腿附近，高压导线通过均压罩上的收线盘收回；
步骤八、利用分阶段加压方式，将施加在海底电缆上的直流高压升高至出厂试验值的75％，并保持15分钟；
步骤九、加压结束后，立即断开电源侧刀闸，利用试验设备及电缆本身的绝缘电阻自然放电，将直流试验电压降至低于300kV；
步骤十、通过微型电动葫芦控制放电车缓慢升高并靠近分压器均压环，使放电尖端与均压环之间产生放电通道，保持10s，然后降低放电车，直到放电通道熄灭，如此往复3次，最 后，再次使放电车缓慢靠近分压器均压环，将放电尖端贴靠在分压器均压环上，直至放电结束，放电过程应在5分钟以上，放电电流不大于100mA；
步骤十一、当放电装置将海底电缆的电压降低至1kV以下时，采用接地线将海底电缆接地，接地线截面不应小于25mm 2，且接地时间不低于24小时，完成整个放电过程。
与现有技术相比，本发明的有益效果在于：
(1)本发明的放电装置，通过放电电阻对耐压试验后的设备进行放电，能快速释放掉大量积累电荷，大幅度缩短了放电时间，提高了耐压试验效率。
(2)本发明的放电装置，可通过远程遥控微型电动葫芦，控制放电车接触被试设备，降低了试验人员的触电风险，极大提高了放电操作的安全性。
(3)本发明的放电装置，结构简单、体积小、可靠性高，便于运输及现场组装，且后期维护简单，极大的降低了电动放电车的使用成本。
(4)本发明的放电方法，利用两台分压器并联的方式减小了放电回路的时间常数RC值，使得自然放电的时间得到大幅度缩短，同时明确了利用试验设备及电缆本身的绝缘电阻自然放电，将直流试验电压降至低于300kV时，再采用放电装置进行快速放电，详细的放电操作步骤也进一步保证了试验人员、被试设备及试验仪器的安全。
附图说明
图1为本发明的电动放电车的整体结构示意图；
图2为本发明的放电车的结构示意图；
图3为本发明的放电电阻的结构示意图；
图4为本发明的均压罩的结构示意图；
图5为本发明的均压罩与放电电阻配合示意图；
图6为本发明的海底电缆在进行直流耐压试验及放电时，分压器与直流高压发生器的位置示意图；
附图标记说明：1-放电车；11-放电尖端；12-万向球；13-锁紧把手；14-滑轮；15-拉绳孔；16-放电车本体；2-均压罩；21-收线盘；22-高压导线；23-均压罩本体；3-拉杆；4-微型电动葫芦；5-放电电阻；51-电阻；52-底座；53-接地柱；6-拉绳；7-定滑轮；8-分压器；81-均压环；82-支撑腿；9-限流电阻；10-直流高压发生器；20-防晕导线；30-海底电缆终端头。
具体实施方式
为使本发明的上述目的、特征和优点能够更加明显易懂，下面结合附图和具体实施方式对本发明作进一步详细的说明。
如图1所示，一种海底充油电缆直流耐压试验的放电装置，包括放电车1、均压罩2、拉杆3、微型电动葫芦4、放电电阻5、拉绳6、定滑轮7和高压导线22。
在进行直流耐压试验时，海底电缆与分压器、直流高压发生器的连接关系如图6所示，为了提高试验系统的可靠性，试验过程中放置了两台分压器8，两台分压器8分别放置在三相海底电缆终端头30之间。分压器8与直流高压发生器10之间用限流电阻9连接，且将两台分压器8并联连接。两台分压器8并联能将分压器8的总电阻降低为原来的1/2左右，放电回路时间常数RC能有效较低，使得自然放电的时间得到较大程度缩短。
定滑轮7安装在分压器8的均压环81底部；拉杆3倾斜布置，下端固定在分压器8的支撑腿82上，上端固定在分压器8的均压环81的专用吊环上；微型电动葫芦4固定在支撑腿82上，放电电阻5则放置在分压器8的一侧。放电车1滑动安装在拉杆3上，拉绳6一端与放电车1连接，另一端绕过定滑轮7后与微型电动葫芦4连接，放电电阻5上端通过高压导线22与放电车1连接，下端接地。如此，微型电动葫芦4可通过拉绳6带动放电车1沿拉杆3上下运动，当放电车1接触均压环81时，即可进行放电。
拉杆3和拉绳6采用绝缘材料制成，例如可以采用尼龙制成，具有良好的强度和绝缘性能，为放电车1的固定轨道。微型电动葫芦4可商购获得，具有紧急制动装置，当在放电过程中发生异常，可以立即使放电车1停止运动，且能对微型电动葫芦4进行远程遥控，确保试验人员的安全。
如图2所示，放电车1包括放电尖端11、万向球12、锁紧把手13、滑轮14、拉绳孔15和车体16。车体16为由两个U型板拼接而成的矩形中空结构，通过锁紧把手13将两个U型板锁紧，两个U型板的侧壁均设有多个滑轮4，从而构成滑轮组，拉杆3为2根，分别从两个滑轮组中间穿过，从而使得放电车1沿拉杆3滑动。万向球12转动连接在车体16朝向分压器均压环一端的固定架上，放电尖端11为杆状，一端固定在万向球12上，另一端的尖端用于接触分压器均压环。由于万向球12可以灵活调节角度，从而可调整放电尖端11的位置以适应不同的试验条件。拉绳孔15则用于绑定拉绳6，而高压导线22则直接绑定在车体16上即可。
如图3所示，放电电阻5用来构成放电通道，释放大量积累电荷，包括电阻51、底座52和接地柱53。底座52用于稳固支撑电阻51，电阻51竖直固定在底座52上，接地柱53连接在电阻51下端。电阻51内部充满变压器油，散热效果好，能承受住较大放电电流及长 的放电时间。电阻51阻值应符合式(1)的计算结果：
Figure PCTCN2019122531-appb-000001
为了放电装置的可靠性，在额定功率下进行放电时，电阻51的可持续稳定放电时间不小于式(2)的计算结果：
T＝1.5×R×C×ln(U d)÷60        (2)
由式(1)和(2)可知，电阻51的额定放电功率不应小于式(3)的计算结果：
Figure PCTCN2019122531-appb-000002
其中，计算过程中裕度系数取1.5；R为电阻阻值，单位为MΩ；T为持续放电时间，单位为min；P为放电功率，单位为W；U d为直流耐压值，单位为kV；C为被试电缆对地电容值，单位为μF。以南方电网海南联网二回海底电缆直流耐压试验为例。通过计算，本次试验中U d取值为-750kV，海底电缆对地电容值为7.49μF，放电电阻电阻值取5MΩ，可持续放电时间要求不小于6.2小时，额定放电功率应不小于102.6kW。
如图4和图5所示，均压罩2与放电电阻5配套使用，在放电过程中起到均压作用，其包括均压罩本体23和收线盘21。压罩本体23呈圆环状，可套在电阻51上端，收线盘21转动连接在压罩本体23上，具体结构根据实际情况进行设计即可。高压导线22一端固定在收线盘21上，平时缠绕在收线盘21的转轴上，放电时拉出，将另一端连接到放电车1上即可，放电完成后，通过收线盘21快速回收高压导线22，提高放电效率。
使用时，首先应将拉杆3固定在分压器均压环上的专用吊环上，同时把拉杆3嵌入放电车1的滑轮14之间，并拧紧锁紧把手13固定住放电车1的车体16，然后将拉绳6穿过定滑轮7，一端与放电车1的拉绳孔15相连，另一端与微型电动葫芦4相连。然后，将均压罩2与放电电阻5固定并放置在平整地面上，保证接地柱53用地线可靠接地。最后，抽出高压导线22，将其与放电车1连接，高压导线22严禁垂落到地面或放电电阻5的底座52上。放电时，利用远程遥控控制微型电动葫芦4，通过收紧拉绳6带动放电车1沿着拉杆3向上前行，直到放电车1的放电尖端11接触到分压器的均压环。
本发明的一种海底充油电缆直流耐压试验的放电方法，具体步骤如下：
步骤一、直流耐压试验开始前，摆放好直流高压发生器10与分压器8的位置，为了提高试验系统的可靠性，试验过程中放置了两台阻性分压器8，两台分压器8分别放置在三相海底电缆终端头30之间，分压器8与直流高压发生器10之间用限流电阻9连接，且将两台 分压器8并联连接，两台分压器8并联能将分压器8的总电阻降低为原来的1/2左右，放电回路时间常数RC能有效较低，使得自然放电的时间得到较大程度缩短。
步骤二、固定拉杆3：把两根尼龙拉杆3挂到分压器8的均压环81的专用吊环上，保持拉杆3间距100mm，另一端利用花兰螺丝吊钩固定在分压器8的支撑腿82的专用吊环上，调节花篮螺丝吊钩收紧尼龙拉杆3，使拉杆3间距均匀一致，便于放电车1滑动。
步骤三、固定拉绳6：拉绳6穿过定滑轮7，把定滑轮7固定到均压环81的专用吊环上(位于辅助拉杆3的中间)。
步骤四、固定微型电动葫芦4：把微型电动葫芦4固定到支撑腿82上，固定位置距离拉杆3约500mm，并将拉绳6的一端固定到微型电动葫芦4的绕线轴上。
步骤五、固定放电车1：松开放电车1的锁紧把手13，把拉杆3嵌在放电车1的滑轮14之间，扣好并旋紧锁紧把手13，然后，将放电尖端11安装到放电车1的万向球12上，拉绳6的另一端系住放电车1，放电尖端11应朝向均压环81。
步骤六、安装放电电阻5和均压罩2：电阻51固定到底座52上，底部连接好接地柱53，顶部安装好均压罩2，把放电电阻5移动到支撑腿82右侧，接地柱53用地线可靠接地，通过高压导线22将放电车1与放电电阻5可靠连接。
步骤七、功能测试：在试验正式开始前，应进行放电装置的功能测试，微型电动葫芦4接通220V交流电源，按上升键时放电车1应带着高压导线22缓缓移向均压环81，到顶部时放电尖端11与均压环81可以可靠接触，按下降键时放电车1应带着高压导线22缓缓移向支撑腿82，功能测试完后放电车1停留在支撑腿82附近，高压导线22重新绕回收线盘21。
步骤八、利用分阶段加压方式，将施加在海底电缆上的直流高压升高至出厂试验值的75％，并保持15分钟。
步骤九、加压结束后，立即断开电源侧刀闸，利用试验设备及海底电缆本身的绝缘电阻自然放电，将直流试验电压降至低于300kV。
步骤十、利用微型电动葫芦4，将放电车1缓慢升高并靠近均压环81，当第一次靠近均压环81，放电尖端11与均压环81之间产生放电通道时，保持原位置10s，随后降低放电车1高度，直到放电通道熄灭；然后第二次使放电车1缓慢靠近均压环81，当放电尖端11与均压环81之间产生放电通道时，保持原位置10s，随后降低放电车1高度，直到放电通道熄灭；第三次使放电车1缓慢靠近均压环81，当放电尖端11与均压环81之间产生放电通道时，保持原位置10s，随后降低放电车1高度，直到放电通道熄灭；然后，第四次(最后一次)使放电车1缓慢靠近均压环81，将放电尖端11贴靠在均压环81上，直至放电结束，放电过程应 在5分钟以上，整个操作过程中实时的观察放电装置串联的电流表，控制放电电流不大于100mA。
步骤十一、当利用本发明的放电装置将被试电缆的电压降低至1kV以下时，应采用专用接地线对被试的海底电缆接地(专用接地线截面不应小于25mm 2)，且保证短路接地时间不低于24小时，完成整个放电过程。
上述实施例只是为了说明本发明的技术构思及特点，其目的是在于让本领域内的普通技术人员能够了解本发明的内容并据以实施，并不能以此限制本发明的保护范围。凡是根据本发明内容的实质所做出的等效的变化或修饰，都应涵盖在本发明的保护范围内。

Claims (7)

  1. 一种海底充油电缆直流耐压试验的放电装置，其特征在于：包括放电车(1)、拉杆(3)、放电电阻(5)、传动装置和高压导线(22)；放电车(1)包括放电尖端(11)、万向球(12)、滑轮(14)和车体(16)，滑轮(14)安装在车体(16)侧面，且与拉杆(3)滚动连接，万向球(12)转动安装在车体(16)上端，放电尖端(11)固定在万向球(12)上，传动装置用于驱动放电车(1)沿拉杆(3)滑动，以使放电尖端(11)与待放电设备接触或者分离。
  2. 根据权利要求1所述的一种海底充油电缆直流耐压试验的放电装置，其特征在于：所述的传动装置包括微型电动葫芦(4)、放电电阻(5)和拉绳(6)，拉绳(6)一端与放电车(1)连接，另一端绕过定滑轮(7)后与微型电动葫芦(4)连接。
  3. 根据权利要求2所述的一种海底充油电缆直流耐压试验的放电装置，其特征在于：所述的拉杆(3)和拉绳(6)采用绝缘材料制成。
  4. 根据权利要求1所述的一种海底充油电缆直流耐压试验的放电装置，其特征在于：所述的放电电阻(5)包括电阻(51)、底座(52)和接地柱(53)，电阻(51)竖直固定在底座(52)上，接地柱(53)连接在电阻(51)下端，电阻(51)内部充满变压器油。
  5. 根据权利要求4所述的一种适用于大容量容性试品耐压试验的电动放电车，其特征在于：所述的放电电阻(5)上端还设置有均压罩(2)。
  6. 根据权利要求5所述的一种适用于大容量容性试品耐压试验的电动放电车，其特征在于：所述的均压罩(2)上还设置有收线盘(21)，所述的高压导线(22)至少部分缠绕在收线盘(21)上。
  7. 一种海底充油电缆直流耐压试验的放电方法，其特征在于：包括如下步骤：
    步骤一、直流耐压试验开始前，摆放好直流高压发生器与分压器的位置，为了提高试验系统的可靠性，试验过程中放置了两台分压器，且将两台分压器并联连接；
    步骤二、固定拉杆：将两根尼龙拉杆挂到分压器均压环专用吊环上，拉杆底部则固定在分压器支撑腿专用吊环上，收紧拉杆，使拉杆间距均匀一致；
    步骤三、固定拉绳：拉绳穿过定滑轮，定滑轮则固定到分压器均压环专用吊环上，定滑轮位于两根拉杆的中间；
    步骤四、固定微型电动葫芦：把微型电动葫芦固定到分压器支撑腿上，并将拉绳的一段固定到微型电动葫芦的绕线轴上；
    步骤五、安装放电车：把拉杆嵌在放电车的滑轮之间，使放电车沿拉杆滑动，把放电尖 端安装到放电车的万向球上，拉绳另一端系住放电车，放电尖端应朝向分压器均压环；
    步骤六、安装放电电阻和均压罩：电阻固定到底座上，底部连接好接地柱，顶部安装好均压罩，把放电电阻移动到分压器旁边，接地柱用地线可靠接地，通过高压导线将放电车与放电电阻可靠连接。
    步骤七、功能测试：在试验正式开始前，应进行放电装置的功能测试，接通微型电动葫芦的电源，按上升键时放电车应带着高压导线缓缓移向分压器均压环，到顶部时放电尖端与分压器均压环可靠接触，按下降键时放电车应带着高压导线缓缓移向分压器支撑腿，功能测试完后放电车停留在分压器支撑腿附近，高压导线通过均压罩上的收线盘收回；
    步骤八、利用分阶段加压方式，将施加在海底电缆上的直流高压升高至出厂试验值的75％，并保持15分钟；
    步骤九、加压结束后，立即断开电源侧刀闸，利用试验设备及电缆本身的绝缘电阻自然放电，将直流试验电压降至低于300kV；
    步骤十、通过微型电动葫芦控制放电车缓慢升高并靠近分压器均压环，使放电尖端与均压环之间产生放电通道，保持10s，然后降低放电车，直到放电通道熄灭，如此往复3次，最后，再次使放电车缓慢靠近分压器均压环，将放电尖端贴靠在分压器均压环上，直至放电结束，放电过程应在5分钟以上，放电电流不大于100mA；
    步骤十一、当放电装置将海底电缆的电压降低至1kV以下时，采用接地线将海底电缆接地，接地线截面不应小于25mm 2，且接地时间不低于24小时，完成整个放电过程。
PCT/CN2019/122531 2019-09-02 2019-12-03 一种海底充油电缆直流耐压试验的放电装置及放电方法 WO2021042601A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201910824349.X 2019-09-02
CN201910824349.XA CN110687405A (zh) 2019-09-02 2019-09-02 一种海底充油电缆直流耐压试验的放电装置及放电方法

Publications (1)

Publication Number Publication Date
WO2021042601A1 true WO2021042601A1 (zh) 2021-03-11

Family

ID=69107699

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2019/122531 WO2021042601A1 (zh) 2019-09-02 2019-12-03 一种海底充油电缆直流耐压试验的放电装置及放电方法

Country Status (2)

Country Link
CN (1) CN110687405A (zh)
WO (1) WO2021042601A1 (zh)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112345893A (zh) * 2020-09-25 2021-02-09 国网浙江省电力有限公司舟山供电公司 带自动放电安全接地装置的大容量直流耐压试验平台
CN112105133B (zh) * 2020-09-27 2023-12-22 山东电力设备有限公司 快速消除套管试验后残余静电荷的方法
CN112379137B (zh) * 2020-11-30 2022-05-10 合肥航太电物理技术有限公司 一种直流静电高压发生器的试验应用
CN113049930A (zh) * 2021-03-19 2021-06-29 中国长江电力股份有限公司 直流耐压试验电动放电装置及放电方法
CN113253068A (zh) * 2021-05-13 2021-08-13 江苏方天电力技术有限公司 一种大长度高压电缆直流耐压试验后放电方法
CN113659554B (zh) * 2021-07-08 2024-01-30 江苏省电力试验研究院有限公司 一种海底电缆快速放电混联电阻优化设计方法
CN113656996B (zh) * 2021-07-08 2024-03-29 江苏省电力试验研究院有限公司 一种海底电缆快速放电策略优化方法及接地网风险控制方法
CN114389197B (zh) * 2021-11-26 2023-11-07 江苏省电力试验研究院有限公司 一种海底电缆放电方法与安全区域规划方法
CN115951178B (zh) * 2022-10-10 2023-09-15 江苏盛华电气有限公司 一种大长度海缆耐压试验集成化移动平台

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0484779A (ja) * 1990-07-27 1992-03-18 Hitachi Cable Ltd 電力ケーブルの部分放電検出方法
CN203883310U (zh) * 2014-06-23 2014-10-15 苏州工业园区海沃科技有限公司 爬行式放电装置
CN205246780U (zh) * 2015-12-17 2016-05-18 中国西电电气股份有限公司 一种电容器试验用放电装置
CN106054033A (zh) * 2016-05-19 2016-10-26 天津送变电工程公司 耐压试验导线伸缩绝缘支架及安全试验方法
CN107907769A (zh) * 2017-12-18 2018-04-13 保定市恒信达电气有限公司 一种定轨爬行装置
CN109683073A (zh) * 2019-02-21 2019-04-26 国网福建省电力有限公司 一种高压直流耐压试验放电的方法
CN109713468A (zh) * 2018-12-24 2019-05-03 中国电力科学研究院有限公司 一种用于实现直流电缆放电的装置及放电方法

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02251775A (ja) * 1989-03-24 1990-10-09 Furukawa Electric Co Ltd:The 直流耐電圧試験の強制放電方法
CN101825649B (zh) * 2009-11-16 2012-08-01 中国南方电网有限责任公司超高压输电公司 特大功率远控放电装置

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0484779A (ja) * 1990-07-27 1992-03-18 Hitachi Cable Ltd 電力ケーブルの部分放電検出方法
CN203883310U (zh) * 2014-06-23 2014-10-15 苏州工业园区海沃科技有限公司 爬行式放电装置
CN205246780U (zh) * 2015-12-17 2016-05-18 中国西电电气股份有限公司 一种电容器试验用放电装置
CN106054033A (zh) * 2016-05-19 2016-10-26 天津送变电工程公司 耐压试验导线伸缩绝缘支架及安全试验方法
CN107907769A (zh) * 2017-12-18 2018-04-13 保定市恒信达电气有限公司 一种定轨爬行装置
CN109713468A (zh) * 2018-12-24 2019-05-03 中国电力科学研究院有限公司 一种用于实现直流电缆放电的装置及放电方法
CN109683073A (zh) * 2019-02-21 2019-04-26 国网福建省电力有限公司 一种高压直流耐压试验放电的方法

Also Published As

Publication number Publication date
CN110687405A (zh) 2020-01-14

Similar Documents

Publication Publication Date Title
WO2021042601A1 (zh) 一种海底充油电缆直流耐压试验的放电装置及放电方法
CN106992469A (zh) 一种输电线路带电作业机器人及其上、下线控制方法
CN103675620A (zh) 一种瓷式绝缘子绝缘测试装置
CN111474467A (zh) 基于六轴机械臂的10kv高压断路器电气试验接线平台
CN110086119A (zh) 一种高压线路检修组合装置及其带电作业方法
CN203117230U (zh) 伸缩式高空试验接线器
CN103558421A (zh) 用于断路器电气试验的接线杆
CN109768486A (zh) 变电站户外横梁10kV隔离开关带电直联装置及方法
CN204190260U (zh) 一种高压输配电线缆跨路架设机具
CN206004213U (zh) 一种用于输电线路巡检机器人上下线的上下线装置
CN107834425B (zh) 架空导线更换施工用接地保护装置
CN107284488B (zh) 带立杆功能的试验手推车
CN112542799A (zh) 一种自锁定电力故障检测维修机构及其使用方法
CN103613032A (zh) 变电站可移动式电缆盖板起重小车
CN107658785A (zh) 丝杠驱动的柱式绝缘子快速更换装置
CN116540021A (zh) 一种可控录波的林牧区电气火灾低压试验装置和方法
CN114104853B (zh) 一种高压开关柜电力电缆抽放装置及其施工方法
CN114784587A (zh) 一种变压器接地线辅助搭接装置
CN113917200A (zh) 自动伸缩遥控高空接线机械手臂
CN110880716B (zh) 高压开关柜线缆接入装置及施工方法
CN109342898A (zh) 一种绝缘工具电气耐压试验接线系统
CN210897695U (zh) 一种通用型临时接地挂环
CN204886031U (zh) 一种辅助接线的装置
CN211236092U (zh) 一种适用于大容量容性试品耐压试验的电动放电车
CN208401377U (zh) 一种用于水电站高压开关站的检修平台

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19944309

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

32PN Ep: public notification in the ep bulletin as address of the adressee cannot be established

Free format text: NOTING OF LOSS OF RIGHTS PURSUANT TO RULE 112(1) EPC (EPO FORM 1205A DATED 16.08.2022)

122 Ep: pct application non-entry in european phase

Ref document number: 19944309

Country of ref document: EP

Kind code of ref document: A1