Solar photovoltaic power generation systems should be how to deal with the lightning

Solar photovoltaic power generation system of the minimum impact resistance voltage of 1. 0 kv, when lightning induced voltage and current is greater than the device resistance rating, will result in equipment damage. Through the analysis, for the first time is struck by lightning, the initial negative polarity polarity lightning, for the first time after the cathode ray

the smallest resistance voltage of solar photovoltaic power generation system is 1. 0 kv, when the thunder is greater than the equipment tolerance induction voltage and current ratings, equipment will be damaged. Through the analysis, the first is struck by lightning, the first negative lightning history, the first negative lightning and thunder electric wave corresponding to the safe distance of 5 respectively. 1, 25. 2, 50. 4 and 9. 8m。 Can be seen from the above analysis, solar photovoltaic power generation system should be based on 2 class architectural configuration of lightning protection lightning protection devices, and lightning protection should be taken to the electric surge intrusion and lightning-proof electromagnetism pulse measures, will generate the lightning induced voltage and induced current control within the allowable range. Solar photovoltaic panels from workshop original lightning protection zone formation of plane stress 0. 45 meters, need to increase the ShanQi to protect the power system. After ShanQi can be lightning rod, wire and network protection. Due to large panels area, while the ground wire and the lightning protection network, but the installation of the wires on the top of the panels and the shadow cast by lightning protection net long cover panels, the serious influence power generation efficiency. In the eaves of buildings, eaves Angle such as vulnerable to lightning location set up multiple independent, highly appropriate lightning rod. Lightning rod high 0. 5 meters, every five meters in decorate a piece on the roof, the corners of dense arrangement. Formation of a bipolar and multipolar protection will greatly reduce the height of the lightning rod and quantity. Lightning rod connected to the existing lightning protection device reliable workshop. The aluminum alloy frame of solar panels and metal stents, with more than 10 was between adjacent panels copper wire connection, form a 'M' shape of the grid structure, forming an electrical pathways, and multiple points of reliable grounding in the neighborhood. Lightning current may well distribution and conduction to the ground. Solar power grounding systems including the lightning protection grounding, safety protection and ac/DC grounding function. It is difficult to separate each grounding system. In order to avoid the back ground potential between the ground system, equipment, metal components and concrete foundation ground net. through fixed connection each other, forming a common ground. The layout of the ground net and size is more important than the specific grounding resistance value. Grounding network based grounding network should be adopted or circular artificial ground net. Omega earthing resistance value should be less than 1. Field measurement of ground net. through power frequency grounding resistance is zero. 8 ohms, and meet the requirements. According to the structure of solar photovoltaic power generation system and thunder electric wave invasion, installed in a circuit coordination of multistage energy surge protector ( SPD) , you can release the lightning current, limit over-voltage, strength in the protected equipment tolerance range. In the introduction of thunder electric wave junction box, namely in LPZ0 area and the border of LPZ1 area, set the level classification experiment of the SPD as a level of protection. Secondary classification experiment of the SPD as a secondary protection installed on the controller, level 3 SPD is installed on the inverter. Level 4 surge protector in the front of the equipment installation, DC load and ac load as the ultimate protection. The first experimental surge protector installed in high voltage side of transformer, in order to prevent the grid side waves into lightning high pressure wave of thunder. Communications equipment and signal lines between total box, controller and inverter are equipped with a suitable signal surge protective device.