  SLED is a crucial component for C-band microwave acceleration unit of SXFEL.
To study the behavior of SLED (SLAC Energy Doubler), mathematic model is
commonly built and analyzed. In this paper, a new method is proposed to build
the model of SLED at SINAP. With this method, the parameters of the two
cavities can be analyzed separately. Also it is suitable to study parameter
optimization of SLED and analyze the effect from the parameters variations.
Simulation results of our method are also presented.
