PEREE 7.1 Basic concepts on soft-switching Hard-switching u a)Turning-on b)Turning-off The process of power semiconductor device hard-switching 5Power E l ect r o n cs i 5 7.1 Basic concepts on soft Basic concepts on soft-switching switching Hard-switching switching t u i u i t u i u i t p t p O O O O a) Turning-on b) Turning-off The process of power semiconductor device The process of power semiconductor device hard-switching switching