这是封装后的子系统，输入接口为D，输出接口为P。
看着像是PD控制器，参考： Simulink model of PD controlled system | Download Scientific Diagram Download scientific diagram | Simulink model of PD controlled system from publication: Investigations on The Design Aspects of First Order Controller For Type 1 Third Order System | Automatic controllers are introduced for efficient control of the process industries. Proportional, Integral and derivative controllers are the most widely used controllers in most of the process industries because of their robustness, easy implementation and simplicity. For... | Systems, Controlling and Process Industry | ResearchGate, the professional network for scientists. https://www.researchgate.net/figure/Simulink-model-of-PD-controlled-system_fig4_275582185
