A Study on Strengthening Standards for Fire Prevention of Anti-freeze Electric Heating Cable

As per the fire statistics survey of 2019, 56.5% (152 cases) of the entire fire accidents (269 cases) caused by heating cables were due to electrical factors. Therefore, in the present work, the electrical factors responsible for heating cable fire have been analyzed, and fire prevention measures have been demonstrated through related reproduction experiments. According to heating cable fire statistics, the fire in anti-freezing appliances (heating cables), except for fires caused by electric cable arcing and other unknown factors, can be classified into four types based on installation configurations. These configurations have been classified and tested according to the Technical Regulations for Electrical and Telecommunications Products and Components (K 10013). The results of a comparative experiment on anti-freezing appliances (heating cable) revealed that the configuration “a type of water pipe with a heating cable wrapped around the water pipe and insulation on the outside” showed the highest temperature among the four installation arrangements. Additionally, the maximum difference between the test temperature (K 10013) and the actual temperature was 40 ℃.

Risk Assessment through Fire and Evacuation Simulation in the Main Control Room of a Domestic Thermal Power Plant

A fire in the main control room of a thermal power plant is a significant threat to the entire power plant by incapacitating the concept of performance design to secure the safety of the power plant. In this study, using the PyroSim and Pathfinder programs to evaluate fire and evacuation risk of the main control room, the appropriate time and fire shape for evacuating people calmly were confirmed when the available safe egress time and required safe egress time of the main control room were compared. In the case of a cable fire, the simulation results indicate the heat generation rate to be more serious than the actual experimental results showed. This is because heat generation was lower in the experiment as the polymer material constituting the cable fell to the floor during combustion and no loger burns. The fire dynamics simulator results indicate that the power plant facility is safe because even these points are not considered.

BN-RA: A Hybrid Model for Risk Analysis of Overload-Induced Early Cable Fires

Cable overload is one of the most critical contributors to early cable fires. This study proposes a hybrid Bayesian network (BN)-based fire risk analysis model, to investigate the evolution of overload-induced early cable fire risks. In particular, the fire risk transmission paths caused by cable overload are reported, considering the critical factors that likely lead to fires. A BN with a specific structure was considered using the fire risk transmission paths. Later, given the risk index system, a hybrid fire risk assessment model caused by cable overload was developed based on the entropy weight method. Subsequently, the corresponding risk levels were evaluated based on the evolution of the fire risk, using numerical simulations. Finally, a case study was conducted to validate the proposed methods, and the results indicated that the proposed methods can effectively evaluate the state of the cable and explain the causes of fire risk, which can be used for early fire warnings.

Influence of Arc Size on the Ignition and Flame Propagation of Cable Fire

Cable fire caused by arc faults is one of the essential factors threatening the safe operation of a power system. The ignition and flame propagation of cable fire dependent on the characteristics of the arc discharge is lackingin in-depth understanding at present. In this work, with the constant electric power deposited into the arc discharge, the effects of arc size on the ignition and flame propagation of 110 kV XLPE cable fire are investigated for the first time. The arc size is changed by varying the gap distance of electrodes from 1.5 cm to 2.5 cm. It is interesting to find that the larger the arc size is, the faster the cable fire is ignited and propagates, and the larger the damaged area of the sheath of the cable is. Therein, when the gap distance increases from 1.3 cm to 3.1 cm, the equivalent impedance and the length of the arc discharge increase nearly seven times and three times, respectively. However, the gas temperature of the arc decreases slightly from 2280 K to 2100 K. In addition, a 3D model of the cable fire ignited by arc discharge is computed by Pyrosim software with fire dynamic simulation (FDS) module. Simulated results show that as the arc size increases, the cable fire is ignited faster, the flame propagates both vertically and horizontally increasing significantly, which is agreed well with the experimental results. This study deepens the understanding of the cable fire ignited by arc discharge and therefore it is useful for the evaluation and prevention of cable fire.

Research on Fire Protection Methods of Cables in Substations

The normal operation of the substation is inseparable from the important guarantee of the cable. The cables in the substation are not only widely distributed, but also the cables are flammable and spread easily after fire. Once a cable catches fire, the consequences will be disastrous. Therefore, how to fire the cable becomes an important task for the power system. Many engineers and technicians continue to analyze and study the causes of cable fires, but cable fire accidents still occur from time to time. In order to solve the problem of cable fire protection and existing problems, the article combines actual research and analysis, and gives the most effective and safe cable fire protection method．