CN111426916A - A method and system for simulating grounding pole line faults - Google Patents

Abstract

The invention relates to a grounding electrode line fault simulation method and system, and belongs to the technical field of high-voltage electricity. The method firstly determines the simulated test tower in the ground electrode line; then installs an auxiliary test device on the simulated test tower; then installs the simulated test device; then installs the simulated lead wire, finally the line is electrified, starts the ground electrode circuit simulation test device, and realizes the ground electrode Line ground fault simulation. The grounding electrode line fault simulation system includes an auxiliary test device composed of an insulating support rod and a vertical wire, and a transmission module, a power module, an input module, a control module, a current detection, and an arc-striking line operation module. Through the fault simulation method and system, accurate simulation of grounding pole line faults can be achieved.

Description

A method and system for simulating grounding pole line faults

technical field

The invention relates to a grounding electrode line fault simulation method and system, and belongs to the technical field of high-voltage electricity.

Background technique

The DC grounding electrode and the DC grounding electrode line are an important part of the DC power transmission project. The grounding electrode line fault simulation is carried out to test whether the DC control and protection system can operate accurately under the fault, and whether the fault location system can accurately carry out the fault. Distance measurement is the most important step in the process of DC engineering debugging. In the traditional DC ground electrode fault simulation, when the test is required, the entire DC line and the DC ground electrode line are first powered off. After the power failure, the test device, such as a short-circuit test frame, is suspended at the ground electrode line test position. Then restore the power transmission, use a catapult device or a crossbow device to bring a grounded arc ignition test wire into the short-circuit test frame, so as to form a fault simulation, or use a manual method to simulate the fault. No matter which one of the two methods is adopted, a power outage is required, and the amount of electricity transmitted by the DC transmission is relatively large, resulting in a large power outage loss. At the same time, the protection of the DC grounding pole line is different from the protection of the DC line and the AC line. When the appeal method is adopted, it is difficult to accurately grasp the duration of the line fault. If the duration is too short, the system will judge it as a disturbance and the protection system will not act. If the duration is too long, the system will be judged as a permanent fault, the system will be blocked, and the power transmission will be stopped, which will bring great adverse effects to the system. How to simulate the fault of the grounding electrode line without power failure and continue for a specified time to achieve the purpose of the test has become a technical problem to be solved urgently in the field.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a grounding pole line fault simulation method and system, which is used to solve the problem that the fault duration cannot be accurately simulated during DC grounding fault simulation, which affects the test efficiency and the normal operation of the power grid.

The technical scheme of the present invention is: a grounding pole line fault simulation test method, the specific steps are:

Step1: Determine the pole tower N of the grounding pole line fault simulation test according to the fault range required by the dispatching, and obtain the pole tower rung height Ht and the insulator string length Lj through the tower map of the pole tower N;

Step2: Install the auxiliary L-type test device on the simulated test tower;

Step3: Install the ground electrode circuit simulation test device;

Step4: Install the fault simulation lead. One end of the fault simulation lead is connected to the tower grounding device, and the other end is connected to the arc-striking wire operating device of the simulation test device;

Step 5: When the line is live, start the grounding electrode line simulation test device to realize the grounding fault simulation of the grounding electrode line.

Preferably, the tower N in the grounding pole line fault simulation test in Step 1 is a tension tower.

Preferably, when the auxiliary L-shaped test device is installed in the Step 2, the height H ₁ of the insulating support rod used for its support to the ground satisfies that the safety insulation to the ground is greater than 3m.

Preferably, when the auxiliary L-shaped test device is installed in the Step 2, the length of the lead wire is L ₃ , L _{3 =} H _t -H ₁ +Δ1+Δ2, and Δ1 is the lead wire on the ground electrode line. The winding length, Δ2 is the length of the lead wire wound on the insulating support rod, and the lead wire is usually made of copper material.

Preferably, before installing the simulated test tower auxiliary L-type test device in Step 2, use aluminum foil tape to wrap the grounding electrode line for protection. .

Preferably, the length of the arc-starting line is determined to be L ₁ in the Step 4;

Among them, k1 is the safety factor, and the value range is between 1.05-1.1. One end of the arc-striking line is connected to the tower grounding device, and the other end is connected to the arc-striking line operation module to achieve fault simulation;

The arc pilot wire is usually a bare copper wire of 1mm ² -10mm ² , one end is connected to the tower grounding device, and the other end is connected to the arc pilot wire.

Preferably, the control method of the Step5 grounding circuit simulation test device is:

Step5.1: Input protection current setting value Iset, time setting value Tset and height H1;

Step5.2: The control module sends a signal to the power module, and through the transmission module, the arc-priming line operating device starts to rise;

Step5.3: Judging whether the rising height of the arc-starting line operating device exceeds the height of the insulating support rod for support;

Step5.4: If the rising height of the arc pilot operating device exceeds the height H1 of the insulating support rod for support, the control module will give the power module a descending signal, and the transmission module will make the arc pilot operating device start to descend and return to the initial position. An abnormal signal is given, the position of the test device does not meet the requirements, and the test ends.

Step5.5: If the rising height of the arc-striking wire operating device does not exceed the height of the insulating support rod for support, judge whether the current detected by the current detection module is less than 0.2Iset, and if it is less than continue to rise;

Step5.6: If the current detected by the current detection module is greater than 0.2Iset, start timing and maintain it at this height;

Step5.7: If the timing exceeds Tset, the control module will give a lowering signal to the power module, through the transmission module, the arc-starting line operating device will start to drop, return to the initial position, and give a signal, the test is normal, and the test is over.

Preferably, the connection of the down conductor of the conductor to the insulating support rod for support and the down conductor of the DC grounding electrode can be performed by means of a power failure operation or by a live operation method. When the live operation method is used, the road near the tension tower should meet the operation requirements of the 10kV insulated bucket truck.

A grounding electrode line fault simulation test system, comprising a grounding electrode simulation test device and an L-shaped auxiliary test device;

The L-shaped auxiliary test device comprises an insulating support rod and a vertical wire, one end of the insulating support rod is connected with the tower, the other end is connected with the vertical wire, one end of the vertical wire is connected with the insulating support rod, and the other end is connected with the grounding electrode wire;

The ground electrode simulation test device includes a transmission module, a power module, an input module, a control module, a current detection module and an arc-starting line operation module;

Transmission module: used to transmit power to the arc pilot line operation module, so that the arc pilot line can be converted from the ground to the L-shaped auxiliary test device to simulate ground faults;

Power module: used to accept the control of the control module and the input module, and provide power to the transmission module;

Input module: used to accept test input related information, including input protection current setting value Iset and time setting value Tset and height H1;

Control module: used to control the arc-striking line operation module, so that the time corresponding to the position after the arc-striking line operation module and the DC grounding line are in contact;

Arc pilot wire operation module: used to pull the arc pilot wire to the grounding electrode line to form artificial grounding. The arc pilot wire operating device is usually insulated, and one end is connected to the arc pilot wire. This end is an S-shaped copper sheet. The arcs are connected, and the other end is connected to the power unit;

The current detection module is used to detect the current flowing through the arc-starting wire, and is used to judge whether to realize the simulation of the fault for the control module.

The beneficial effects of the invention are as follows: the problem that time and current are difficult to control during the short circuit process of the DC ground electrode line is realized, and the success rate of the ground electrode short circuit test is improved.

Description of drawings

1 is a schematic structural diagram of a direct pole line fault system of the present invention;

Fig. 2 is the control flow chart of the test device of the present invention.

In the picture: 1- Conductor down lead, 2- Insulation support rod, 3- Fault simulation lead, 4- Arc-starting wire operating device, 5-S type copper sheet

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

Embodiment 1: As shown in Figure 1-2, a grounding electrode line fault simulation test method includes the following steps:

Step1: Determine the tower N of the grounding pole line fault simulation test according to the fault range required by the dispatching, obtain the tower rung height Ht and the insulator string length Lj through the tower map of the tower N, and select the tower for the simulation test outside the converter station according to the dispatching requirements. The first base tower is a tensile tower. According to the drawing of the base tower, the height Ht of the rungs is 18m, and the length Lj of the insulator string is 0.73m.

Step2: Install the auxiliary L-type test device on the simulated test tower. The height H1 of the insulating support rod 2 to the ground meets the ground safety insulation greater than 3m. According to the tower drawing in the first step, choose 4m; in the grounding pole line The length of the upper winding is 0.5m, the winding length on the insulating support rod 2 is 0.2m, the length L3 of the lead wire 1 is 4.7m, the copper wire with a transparent outer sheath is selected for the lead wire 1, and the cross-sectional area is 25mm ² , L3=Ht-H1+Δ1+Δ2, Δ1 is the length of the downconductor 1 wound on the grounding line, Δ2 is the length of the downconductor 1 wound on the insulating support rod 2, the The lower wire 1 is usually made of copper material. Before installing the auxiliary L-shaped test device, an aluminum-clad tape is also installed on the grounding electrode line for protection, with a width of 15cm. The installation method is power failure installation.

Step3: Install a ground electrode circuit simulation test device; the ground electrode simulation test device includes: a transmission module, a power module, an input module, a control module, a current detection module and an arc-striking line operation module;

Transmission module: used to transmit power to the arc pilot line operation module, so that the arc pilot line can be converted from the ground to the L-shaped auxiliary test device to simulate ground faults;

Power module: used to accept the control of the control module and the input module, and provide power to the transmission module

Input module: used to accept test input related information, including input protection current setting value Iset and time setting value Tset and height H1;

The control module is used to control the arc pilot operation module, so that the arc pilot operation module and the DC ground electrode line are in contact with the position corresponding to the time

The arc-striking wire operation module pulls the arc-striking wire to the grounding electrode line to form artificial grounding. The arc-striking wire operating device 4 is usually insulated, and one end is connected to the arc-striking wire. The arcs are connected, and the other end is connected to the power unit.

The current detection module is used to detect the current flowing through the arc-starting wire, and is used to judge whether to realize the simulation of the fault for the control module;

其中k1为安全系数，取值1.1之，将引弧线一端与杆塔接地装置连接，另一端与通过引弧线操作模块实现故障模拟；该引弧线截面积为2mm²，一端连接杆塔接地装置，另一端连接引弧线。Step4: Install the fault simulation lead 3, one end of the fault simulation lead 3 is connected to the tower grounding device, and the other end is connected to the arc-striking wire operating device 4 of the simulation test device; the length of the arc-striking wire L1,

Among them, k1 is the safety factor, and the value is 1.1. One end of the arc pilot is connected to the tower grounding device, and the other end is connected to the arc pilot operation module to achieve fault simulation; the arc pilot line has a cross-sectional area of 2mm ² and one end is connected to the tower grounding device. , and the other end is connected to the arc lead.

Step 5: When the line is live, start the grounding electrode line simulation test device to realize the grounding fault simulation of the grounding electrode line.

In the process of starting the ground electrode circuit simulation test device in Step5, the following steps are also included

Step5.1: Input protection current setting value Iset, 1000A, time setting value Tset, 0.2S and height H1, 4m;

Step5.2: The control module sends a signal to the power module, and the arc-priming line operating device 4 starts to rise through the transmission module;

Step5.3: Determine whether the height of the arc-starting wire operating device 4 exceeds the height of the insulating support rod 2 for support;

Step5.4: If the rising height of the arc pilot operating device 4 exceeds the height H1 of the insulating support rod 2 for support, the control module will give the power module a descending signal, and the arc pilot operating device 4 will start to descend through the transmission module and return to The initial position, an abnormal signal is given, the position of the test device does not meet the requirements, and the test is over.

Step5.5: If the rising height of the arc-striking wire operating device 4 does not exceed the height of the insulating support rod 2 for support, judge whether the current detected by the current detection module is less than 0.2Iset, and if it is less than continue to rise;

Step5.6: If the current detected by the current detection module is greater than 0.2Iset, start timing and maintain it at this height;

Step5.4, if the timing exceeds Tset, the control module will give a lowering signal to the power module, and through the transmission module, the arc pilot operating device 4 will start to lower, return to the initial position, and give a signal, the test is normal, and the test is over.

The specific embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned embodiments, and can also be made within the scope of knowledge possessed by those of ordinary skill in the art without departing from the spirit of the present invention. Various changes.

Claims (8)

1. A grounding electrode line fault simulation test method is characterized in that:

step1, determining a tower N of the grounding electrode line fault simulation test according to the fault range required by the dispatching, and acquiring the height Ht of a tower crosspiece and the length L j of an insulator string through a tower diagram of the tower N;

step2, mounting an auxiliary L type test device on the simulation test tower;

step 3: installing a grounding electrode circuit simulation test device;

step 4: installing a fault simulation lead, wherein one end of the fault simulation lead is connected to a tower grounding device, and the other end of the fault simulation lead is connected with an arc striking wire operating device of a simulation test device;

step 5: and (4) the circuit is electrified, and the grounding electrode circuit simulation test device is started to realize grounding electrode circuit grounding fault simulation.

2. The earth electrode line fault simulation test method of claim 1, characterized in that: and the tower N of the grounding electrode line fault simulation test in Step1 is a strain tower.

3. The method of claim 1, wherein when the auxiliary L test device is installed in Step2, the position of the insulating support rod for supporting the device is higher than the ground height H₁The requirement of safe insulation to the ground is more than 3 m.

4. The method of claim 1, wherein when the auxiliary L test device is installed in Step2, the length of the down lead of the lead is L₃，L_3＝H_t-H₁+ Δ 1+ Δ 2, Δ 1 is the length that the lead downlead twined on the ground polar line, and Δ 2is the length that the lead downlead twined on the insulating support rod, the lead downlead be copper material.

5. The grounding electrode line fault simulation test method of claim 1, wherein before the Step 2is provided with the simulation test tower auxiliary L type test device, an aluminum foil tape is adopted on a grounding electrode line for winding protection, the protection range meets 3-4 times of the diameter of a vertical lead, and the width is not less than 10cm-20 cm.

6. The grounding electrode line fault simulation test method of claim 1, wherein the length of the leading arc line determined in Step4 is L₁；

Wherein k1 is a safety factor, the value range is 1.05-1.1, one end of the arc striking wire is connected with the tower grounding device, and the other end of the arc striking wire realizes fault simulation through the arc striking wire operation module;

the arc leading line is 1mm²-10mm²One end of the bare copper wire is connected with the tower grounding device, and the other end of the bare copper wire is connected with the arc leading line.

7. The earth electrode line fault simulation test method of claim 1, characterized in that: the control method of the Step5 grounding electrode circuit simulation test device comprises the following steps:

step5.1: inputting a protection current setting value Iset, a time setting value Tset and a height H1;

step5.2; the control module gives a signal to the power module, and the arc striking wire operating device starts to ascend through the transmission module;

step5.3: judging whether the rising height of the arc striking wire operating device exceeds the height of the insulating support rod for supporting or not;

step5.4: if the rising height of the arc striking line operating device exceeds the height H1 of the insulating support rod for supporting, the control module gives a descending signal to the power module, the arc striking line operating device starts to descend through the transmission module, returns to the initial position and gives an abnormal signal, the position of the test device does not meet the requirement, and the test is finished.

Step5.5: if the rising height of the arc leading line operating device does not exceed the height of the insulating supporting rod for supporting, judging whether the current detected by the current detection module is less than 0.2Iset, and if the current detected by the current detection module is less than the height of the insulating supporting rod for supporting, continuing rising;

step5.6: if the current detected by the current detection module is greater than 0.2Iset, starting timing and maintaining the timing at the height;

step5.7: if the timing exceeds Tset, the control module gives a descending signal to the power module, the arc striking wire operating device starts to descend through the transmission module, the arc striking wire operating device returns to the initial position, a signal is given, the test is normal, and the test is finished.

8. A grounding electrode circuit fault simulation test system is characterized by comprising a grounding electrode simulation test device and an L type auxiliary test device;

the L type auxiliary test device comprises an insulating support rod and a vertical lead, wherein one end of the insulating support rod is connected with a tower, the other end of the insulating support rod is connected with the vertical lead, one end of the vertical lead is connected with the insulating support rod, and the other end of the vertical lead is connected with a ground electrode lead;

the grounding electrode simulation test device comprises a transmission module, a power module, an input module, a control module, a current detection module and an arc striking wire operation module;

the transmission module is used for transmitting power to the arc leading line operation module, so that the arc leading line can be converted from the ground to an L type auxiliary test device, and the simulation of the ground fault is realized;

a power module: the control module is used for receiving the control of the control module and the input module and providing power for the transmission module;

an input module: the device is used for receiving relevant information of test input, including an input protection current setting value Iset, a time setting value Tset and a height H1;

a control module: the control module is used for controlling the arc striking line operation module to enable the arc striking line operation module to be in contact with the direct-current grounding polar line for a corresponding time;

leading an arc line operation module: the arc striking wire operating device is insulated, one end of the arc striking wire operating device is connected with the arc striking wire, the other end of the arc striking wire operating device is connected with the power device, and the S-shaped copper sheet is connected with the arc striking wire through a bolt;

and the current detection module is used for detecting the current flowing through the leading arc line and judging whether the fault simulation is realized for the control module.

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