How to prevent lightning and fire in distributed photovoltaic system

Lightning is a phenomenon of atmospheric discharge. In sex in the process of formation, some part of it has amassed a positive charge and the other part of the accumulation of negative charge, when the charge accumulation to a certain extent, can produce electric discharge phenomenon, thunder and lightning. Ray

lightning is a discharge from the atmosphere. In the process of the formation of clouds and rain, part of the accumulation of positive charge, the other part of negative charge accumulation. When the charge accumulation to a certain extent, discharge phenomenon occurs, and forms of lightning. Lightning can be divided into direct lightning and induction lightning. Direct lightning refers to direct fell on the photovoltaic array, DC power distribution system, electrical equipment and circuit such as a lightning strike. And nearby areas. Direct lightning invasion has two ways: one is direct discharge of pv arrays, etc. As mentioned above, make the most of high-energy lightning current was introduced into the building or equipment and circuit; The other is a lightning can directly through the lightning rod and other direct lightning discharge device conduction to the ground, lead to ground potential instant rise, most of the lightning current through reverse flow into the device and circuit protection grounding line. Induction lightning is struck by lightning in buildings, equipment and related circuit near or beyond, buildings, equipment and related line overvoltage. The transient overvoltage by electrostatic induction or electromagnetic induction to connect to the related electronic devices and circuit, damages to the equipment and lines. Except the lightning surge voltage and current, in the high power circuit closing and opening, the perceptual load and capacitive load on and off, power system or transformer off moment also can produce larger switching surge voltage and current, will cause harm to the related equipment and circuit. Large photovoltaic power generation system or installed in the empty open area and the mountain system must be equipped with lightning protection and grounding device, especially in areas vulnerable to lightning. The harm of lightning on photovoltaic power generation system ( 1) Damage of solar cell module. The core part of solar panels is solar power system, also is the most valuable part of the solar system. Its function is to convert the sun's radiant energy into electrical energy, or put it into storage battery, or promote work load. However, its position are highly susceptible to strong impulse current, high temperature and strong power of the impact of direct lightning, lead to paralysis of the whole system. ( 2) The harm of photovoltaic controller. Photovoltaic controller's function is to control the working state of the whole system, to prevent the battery overcharge and over discharge. When the system is lightning strike or overvoltage damage, the following will happen. ( 1) Charging system is charging, discharge system did not discharge, remain the state of rechargeable batteries. If charging full light, and capacity will shorten the life of the battery, and if charging is overweight, battery will explode, caused the damage and casualties of the whole system. ( 2) Charging system is not charging, remain the state of discharge, the discharge system of battery cannot store electricity, this allows the user equipment can work normally when the sunshine, no sunshine or equipment can't work when the light is not strong. ( 3) The harm of the battery. Solar photovoltaic power generation systems usually use lead-acid battery, nickel metal hydride batteries, nickel-cadmium batteries or lithium batteries can also be used for small and micro system. Its function is when there is light store electric energy from solar panels, and released when needed. When the system had been struck by lightning and overvoltage into the battery, will damage the battery, shorten the service life of the battery, or will cause the battery explosion, causing severe system failure and loss of life.