Through the method used to study system's input-output stability and working out the LMI problem, we can attain the incremental-gain of nonlinear system.

Through the method used to study system's input-output stability and working out the LMI problem, we can attain the incremental-gain of nonlinear system. In this paper, two examples are given.

It has excellent output stability by following up the variation of input voltage and connected load, they almost can't be damaged in normal use.