TIDUF22 January 2023
A lighting surge test between line and neutral was evaluated. The design can survive a 4-kV surge test. A surge causes a one-shot-trigger interrupt, if the firmware stops PFC at OST interrupt, the surge test is Grade C since PFC stops and does not start automatically. If firmware does not stop PFC at OST interrupt, PFC keeps working, and the surge test result is Grade A. Figure 3-21 shows the 4-kV line to neutral surge voltage waveform.