Protective measures for power cable faults

Electric wires and cables play a crucial role in the infrastructure construction of our country. Power cables are commonly used in urban underground power grids, power station outgoing lines, internal power supply of industrial and mining enterprises, and underwater transmission lines crossing rivers and seawater. They are composed of four parts: wire core, insulation layer, shielding layer, and protective layer, and are one of the essential materials for transmitting power and energy. They are widely used in economic production. In the event of cable failure, Not only will it threaten the safe and stable operation of the power grid, but it will also cause economic losses to enterprises, and in severe cases, it can cause chain damage reactions. Therefore, how to quickly identify problems, solve faults, and prevent the occurrence of faults has become a major issue of concern in the current power industry。

Protective measures for power cable faults

1. Choose suitable cables for different transmission lines

When laying transmission lines, power workers should choose economical and practical cables based on the surrounding environment of the laying line. The origin of oil-paper cables is relatively early, and the production process is relatively complete. The structure is simple, and the production process is also relatively simple. However, it has a defect that the low melting point insulation oil is prone to heat flow. When laying under high voltage differential, the insulation oil of the cable will flow from high to low, resulting in the drying of the insulation layer at high places and reducing its own insulation performance. The increase in oil pressure at low places can cause lead wrapping cracking and lead to faults. Therefore, the selection of cables when laying transmission lines is particularly important. Nowadays, power systems generally use cross-linked polyethylene insulated cables, which can avoid faults under the influence of high drops and expand the transmission capacity of the cables.

2. Enhance the professional skills of staff and reduce human caused failures

The normal operation of a transmission line is entirely determined by the quality of cable engineering construction. If the quality meets the standards during construction and the operation method is appropriate, it can ensure the safe, long-lasting and stable operation of the circuit. We must provide technical training to cable construction and operation personnel in our daily work to improve their technical level and reduce the occurrence of human caused faults.

3. Strengthen supervision of load current

According to the operation regulations of power cables, it is not allowed to generate overload current during line operation, which can cause the temperature of the cable to rise. This will aging the cable and affect its service life, reducing its insulation performance. Once there is a weak insulation performance in the circuit, there is a possibility of breakdown accidents. Therefore, we must strengthen current monitoring to avoid breakdown accidents caused by overload.

4. Strengthen line inspection

Conduct planned and focused inspections of the locations where faults occur and are prone to occur on the transmission line. Once any faults are found, they should be promptly addressed to prevent tripping events from affecting the stable operation of the power system. Generally speaking, circuit patrol personnel should meet the following requirements: first, they should have good physical quality, because no matter in hot or cold weather, even in typhoon and rainstorm weather, patrol personnel need to conduct safety patrol on power supply lines, so the quality of physical quality directly affects the quality of patrol; Secondly, line patrol personnel should have a high sense of responsibility. Only by ensuring the quality and quantity of line patrol work can faults be detected and dealt with in a timely manner; Once again, one should dare to face the problem directly. When a temporary fault occurs on the power supply site, it can sometimes be directly pointed out and stopped, so that the fault can be eliminated in a timely manner. Regardless of the situation, it is necessary to adapt to the situation and prioritize resolving faults as soon as possible to ensure the safe and stable operation of the power supply line. Therefore, power line patrol personnel should be more careful and try their best to eliminate potential power hazards during the inspection.

5. Supervise the insulation performance of cables and strive to detect potential flashover faults in the cables in a short period of time

Flashover faults of cables generally occur during preventive testing. Therefore, by conducting cable preventive tests in a planned manner and enhancing monitoring of cable insulation performance, we can identify faults during preventive tests and reduce the occurrence of faults.

6. Preventive Measures for Tripping Faults of Transmission Lines

Line tripping is one of the frequent faults in transmission lines, which is generally caused by factors such as equipment itself, external environmental factors, or human factors of personnel. Once a tripping fault occurs in the transmission line, it will lead to the paralysis of the entire transmission line, and if this fault cannot be detected and resolved in a timely manner, it will bring inconvenience to people’s normal life and even cause varying degrees of economic losses to enterprises. Therefore, during daily line inspections, it is necessary to carefully investigate and avoid tripping accidents as much as possible. We also need to analyze the operation of the line and the locations where faults are prone to occur in detail, summarize the rules of their occurrence, and take appropriate protective measures based on evidence to ensure the safe and stable operation of the line.

7. When laying cables, avoid or protect against adverse environments

If there are corrosive substances such as acids and alkalis or underground sewage in the surrounding environment where cable lines are to be laid, we need to consider whether to replace the laying position or take effective pollution prevention measures before laying. In response to this issue, our power designers are required to carefully investigate and inquire about the local address pollution situation when surveying and laying the line.

8. Repair and improve unclear cable markings

After the completion of cable laying, signs are usually set up at the laying location to avoid other construction personnel from being unaware of underground cable laying and causing cable excavation damage or stacking heavy objects here. Over time, some signs may have unclear markings, which requires our line patrol personnel to promptly detect and handle them to ensure the safe operation of the line.

To sum up, the quality of power cables directly affects the operation safety of the line. Once the line cannot operate safely and stably, the life and economic losses caused by its failure are unpredictable. Therefore, our power workers should fundamentally prevent the occurrence of cable failures and minimize cable accidents, starting from the details, and strive to achieve the goal of safe and stable power supply.

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Kvtester Electronics Technology Co.,Ltd. is a high-tech enterprise specializing in power testing, testing, research and development, production, and sales of testing equipment. It has been engaged in the electrical testing industry for many years, and its products are of high quality. We welcome customers to come and purchase.