低压配电系统电涌保护器能量配合研究

电涌保护器(SPD)的能量配合是低压配电系统防雷工程中的重要课题。基于理论计算和ATP-EMTP仿真,研究一端口限压型SPD在短波(8/20μs)和长波(10/350μs)下的能量配合问题,着重分析SPD级间距离和参数配合对这种配合的影响。提出金属氧化物压敏电阻(MOV)伏安特性研究的一种假设,给出了级间电缆的长度与后级SPD分流比的关系曲线。结果表明:短波情况下,10 m的级间电缆可将后级SPD电流限制在总电流的20%以内;长波情况下,80 m的级间电缆才能达到相近的效果。

Research on Energy Coordination of SPD in Low-voltage Distribution System

Energy coordination of surge protective devices(SPDs) is an important issue of lightning protection in low-voltage distribution system.Based on theoretical calculations and ATP-EMTP simulation,energy c oordination issue of one-port voltage limiting type SPD is researched under short wave(8/20 μs) and long wave(10/350 μs) condition.The distance between SPDs and parameters coordination are analyzed.An assumption on metal oxide varistors(MOVs) current-voltage curves research is proposed and the limiting effect of the cable in the different lengths on the second-stage SPD current is researched.The results show that,10 meters long cable can make that the current of second interstage SPD is limited to less than 20% of total current under short wave condition;but it needs 80 meters cable to achieve the same effect under long wave condition.