Application Research of ESO in Solving Parasitic Resistance in CPL System

In this paper, extended state observer(ESO) is used to solve the static-state error caused by parasitic resistance in Buck converter with constant power load(CPL). Firstly, the control algorithm based on passivity-based control(PBC) is designed to solve the problem that the Buck converter with CPL can not operate stably, and the influence of parameter change on the control system is analyzed by using the zero-pole map. The influence caused by parasitic resistance is regarded as unknown disturbance, and it is estimated by ESO to reduce the control static-state error. Finally, the problem of non-convergence is solved by improving the fal function commonly used in ESO. Computer simulation shows the effectiveness and feasibility of the control strategy designed in this paper.