Pulsed EMI protection in electronic power supplies

The author studies the nature of various pulsed electromagnetic interference (EMI) sources, their effects on electronic power supplies, and different types of protection circuitries, as well as the design constraints on these circuitries. The different pulsed EMI sources are described, with special emphasis on lightning. The power failure mechanisms caused by a lightning transient are identified, and different lightning protection circuitries, design constraints, system ground configurations, as well as radiated and conducted EMI and safety considerations are introduced. Several novel protection schemes that have been used in a number of electronic power supply products are presented