Add to ORKGIt is well known that if the linear time invariant system ˙x=Ax+Bu, y=Cx is passive the associated incremental system˙˜x=A˜x+B˜u, ˜y=C˜x, with (˜·)=(·)−(·), u, y the constant input and output associated to an equilibrium state x, is also passive. In this paper, we identify a class of nonlinear passive systems of the form ˙x = f(x) + gu, y = h(x) whose incremental model is also passive. Using this result we then prove that a large class of nonlinear RLC circuits with strictly convex electric and magnetic energy functions and passive resistors with monotonic characteristic functions are globally stabilizable with linear PI control.