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Damage of electronic equipment and power supply failure

Lightning itself is only an ordinary weather phenomenon. The reason why it becomes a disaster is that the huge energy it releases in an instant has caused damage to our lives and property. Lightning disaster generally refers to the event that the invasion and impact of lightning or lightning electromagnetic pulse cause casualties or financial damage, partial or total loss of function, and lead to adverse social and economic consequences. The loss of lightning disaster includes direct casualties and economic loss, as well as the resulting economic loss and adverse social impact. According to the types of accidents, lightning disasters can be roughly divided into five categories, namely casualty accidents, electronic equipment damage accidents, power supply failure accidents, fire and explosion accidents and building damage accidents, of which the former three have the most serious impact.
Damage of electronic equipment — the most common trouble in lightning internal lightning protection needs attention
Case playback: on April 19, there was a rainstorm in FASI Town, Jiangxia District, Wuhan, followed by lightning. More than 10 televisions in the homes of 25 villagers in Sanhe Village of the town were damaged, and several set-top boxes, water heaters and refrigerators were burned out, resulting in a loss of nearly 100000 yuan. The survey found that in this village, TV sets are most vulnerable to lightning damage. “After the thunder and lightning the year before last, the TV was damaged. It was damaged by thunder and lightning in the second half of last year. Unexpectedly, it was damaged by lightning again in less than half a year.” A villager wondered: houses without lightning rods will be damaged. Why are electrical appliances also damaged in houses with lightning rods.
Work is inseparable from computers and mobile phones. For current urban residents, this is a very common living state. Even in rural areas, household appliances have long become a necessity of life. Electronic equipment has always been the favorite object of lightning “Shiwei”. With the more and more extensive application of similar electronic intelligent equipment, the damage of electronic equipment has become the main disaster type. According to the compilation of major lightning disasters in China from 1998 to 2012, in many regions, cases of damage to electronic equipment account for more than 50% of the total proportion of lightning disasters.
Why electrical appliances will be damaged when lightning rods are installed is a common problem. In fact, this is because lightning protection is divided into internal and external parts. Lightning rods are only external lightning protection measures and can not “beat the world”.
The principle of lightning rod is to actively “guide” lightning to the lightning arrester according to the line designed by people, and finally safely lead it into the earth from the grounding body through the down lead. However, there is also the phenomenon of lightning bypassing the lightning rod and hitting the building. In addition, lightning rods can only protect against direct lightning, but they can’t do anything about induction lightning, which is the “number one killer” of electronic and electrical equipment.
Induction lightning is caused by the rapidly changing strong magnetic field generated by the huge impulse lightning current in the surrounding space during lightning discharge. It can propagate along the circuit or through the space electromagnetic field. In case of electronic and electrical equipment, it may produce discharge sparks, causing fire, explosion or electric shock.
Internal lightning protection measures, such as electromagnetic shielding, equipotential connection, installation of surge protector, reasonable wiring, etc., shall be adopted to prevent induced lightning. Nowadays, although some buildings are equipped with external lightning protection facilities such as lightning rods, they fail to protect the electrical safety when lightning strikes.
When microelectronic technology is widely used and permeates into various production and life fields, microelectronic devices are extremely sensitive, which is easy to be invaded by omnipresent lightning electromagnetic pulse, resulting in equipment out of control or damage.
LV Haiyong of Guangdong lightning protection and Disaster Reduction Center believes that the damage of electronic equipment has become the main disaster caused by lightning, which indicates that lightning protection technology needs to enter a new era, and lightning protection and disaster reduction work also faces new challenges, because the damage of electronic equipment not only causes direct economic losses, but also equipment damage Network interruption will also bring immeasurable indirect losses.
Casualties – the human consequences of lightning strike are unimaginable and the risk of lightning strike is high
Case playback: on April 24, on a hilltop on Tianqiao West Road, Yulin City, Guangxi Zhuang Autonomous Region, three charred bodies were found in a simple shed burned by a fire. After receiving the report, the police intervened in the investigation and confirmed that the deceased was a family of three scavengers, including a couple and a two-year-old girl. According to the analysis of relevant technicians, the three dead may have been killed by lightning in the rainstorm in the early morning of April 23.
According to statistics, about 0.53 people in every 1 million people die from lightning disasters every year. Although this figure is difficult to compare with the death toll caused by traffic accidents, lightning is still feared by people because of its sudden and fatal.
Statistics show that the death rate of lightning injury is about 10%, but even if there is no death, lightning will cause permanent damage, including heart disease, memory loss, sleep disorder and epilepsy. Therefore, in the face of lightning, people’s best self-protection method is “walking is the best policy”.
In ancient times, people often regarded “Heaven beating and lightning splitting” as a scourge, which also confirmed people’s helplessness in the face of lightning. In fact, with the corresponding knowledge, lightning injury can also be prevented.
Jia Xiushu, a researcher at the Institute of Atmospheric Physics of the Chinese Academy of Sciences and a lightning expert, explained that there are four main ways for lightning to hurt people, namely, direct lightning strike, contact voltage (electric shock when touching the object being struck by lightning), side flash (when it is near the object being struck by lightning, the current strikes through the air and pours into the earth through the human body) and step voltage.
Most lightning deaths occur outdoors. No matter which way lightning intends to hurt people, it is easier to succeed outdoors. Therefore, in case of lightning, try not to go outdoors.
But it’s hard to avoid. There are always thunderstorms outside. At this time, people should keep in mind that lightning is “principled”. It will give priority to high-point attacks. Tall objects such as iron towers, chimneys and electric poles are the targets of lightning. To stay away from them is to reduce the probability of being damaged by contact voltage, side flash and step voltage.
It is common sense that lightning protection under trees is very dangerous, but lightning protection is also very dangerous in temporary buildings without lightning protection measures such as field huts and shacks. In many casualty cases, lightning strikes are caused by avoiding thunderstorms in shacks. The shack is also applicable to the principle of lightning high point attack. In the open and flat field, such buildings built by people are very easy to cause lightning attack, and the risk factor is no less than standing directly in the field. Moreover, the shack is easy to catch fire after being hit, and the harm is more serious.
In addition, when the lightning is fierce, the metal objects on the body may cause secondary damage to the body due to inductive lightning, and should be resolutely discarded if necessary. If many people lightning together, do not walk hand in hand because of fear, and keep a certain distance from each other, otherwise if one person is struck by lightning, all will suffer.
Power supply failure – hit a point and affect a piece of scientific prevention and rapid disposal & nbsp;
Case playback: on July 23, 2010, the South extension line of Nanjing Metro Line 1 was struck by lightning, resulting in two failures of power supply catenary, 4 trains delayed operation due to catenary power failure, and the travel of more than 2000 passengers was affected to varying degrees.
Lightning is the primary cause of power grid failure, which seriously threatens the safe operation of power grid. China’s power grid suffers more than 350000 lightning strikes every year, and the number of transmission system trips due to lightning strikes accounts for more than 50% of the total trips.
Once lightning damages the power supply equipment, it will cause power cuts in different ranges and times. Although its occurrence is only about one third of the damage of electronic equipment, the impact is very huge. The interruption of production and domestic electricity will trigger a series of chain reactions. Take the subway failure in the case as an example. After the subway power failure caused by lightning, a large number of passengers stay in the train and station, which will also have a great impact on social order.
Different from the electronic equipment usually hiding indoors, the power grid is usually faced with the threat of direct lightning and inductive lightning at the same time. The flood season with frequent lightning is also the peak period of power consumption. While doing a good job in external and internal lightning protection measures, it must be considered that facing strong lightning, losses are sometimes difficult to avoid. Prevention in advance is only one aspect, and the ability of rapid repair is also the focus of stopping losses.
Nowadays, many regions have established a rapid response mechanism to deal with power supply failures caused by lightning. The emergency repair team determines the lightning disaster risk points according to the weather forecast in advance, deploys and inspects in advance, and can quickly rush through in case of accidents, or takes temporary power supply measures to ensure normal production and living power consumption.