电工技术2（Electrical Engineering 2）.doc

电工技术2（Electrical Engineering 2） Surge protection in electrical equipment room The author of this article from the anonymous electromechanical house With the rapid development of electronic technology, integrated circuit of voltage and current pulse sensitive degree is more and more high, external surge overvoltage and internal surge has become one of the main factors of electronic equipment damage and the interruption of work. The basic requirement to ensure that the precision electronic equipment system can work properly is that the surge protection design should be properly and properly coordinated so as to avoid equipment damage due to external surge, overvoltage and internal surge. In addition, qualified and excellent quality products must be selected. ????? an important electrical equipment room construction and expansion projects should adopt the high-quality power surge protector, surge protection measures provided to improve the electrical system, and voice, data and image and other metal conductor cable transmission weak network should also do this is to ensure that the surge protection, an important technical link of this kind of equipment is normal work. 1. The generation of surges Surge is an abnormal high current pulse in microsecond order. Its wave head time is generally 0.25~20 s, and its unit energy is generally 2.5~10MJ / omega. It can cause the electronic equipment to be damaged by transient overvoltage. Each year, the integration of semiconductor devices is increasing, the space between components is decreasing, and the thickness of the semiconductor is becoming thinner. This makes it possible for electronic equipment to be damaged by transient overvoltages. If the transient overvoltage caused by a surge exceeds the capacity of an electrical device, the electrical component or device is completely destroyed, or the service life is greatly shortened. Lightning is the most obvious cause of the surge, and lightning strikes the transmission lines, cau