隔离型交?直流固态变压器前后级一体化滑模控制

为了提高固态变压器(SST)控制系统的动态性能和鲁棒性，提出SST前后级一体化滑模控制方法. 根据SST前后级的非线性特性，建立整体仿射非线性的数学模型，采用输入?输出精确反馈线性化，实现前级电流环、前后级级间电压以及SST直流侧电压的解耦，加强前后两级功率传递的一致性. 将解耦的线性系统与积分滑模控制器结合，进一步提高系统整体动态性能，改善系统对参数摄动的鲁棒性. 仿真和实验结果表明，在外部发生扰动时，SST采用一体化滑模控制方法能够快速、有效地调整电网侧电压、两级间电压和直流侧电压的波动，改善前、后级功率传递的一致性，在发生参数变化时仍具有较强的鲁棒性.

Isolated AC-DC solid state transformer front and rear stages integrated sliding mode control

An integrated sliding mode control method of front and rear stages of solid-state transformer (SST) was proposed, in order to improve the dynamic performance and robustness of SST control system. According to the nonlinear characteristics of the front and rear stages of SST, the mathematical model of overall affine nonlinearity was established. The input-output precise feedback linearization was used to decouple the front stage current loop, the voltage between the front and rear stages and the voltage on the DC side of SST. The consistency of the power transfer for the two converter stages was enhanced. The decoupling linear system was combined with the integral sliding mode controller to further improve the overall dynamic performance of the system and improve the robustness of the system to parameter perturbation. The simulation and experimental results show that in case of external disturbance, SST adopts the integrated sliding mode control method, which can quickly and effectively adjust the fluctuation of grid side voltage, two-stage voltage and DC side voltage, improve the consistency of power transmission between the two stages, and has strong robustness in case of parameter change.