Hi Rainy,
Normally, for discontinuous systems like those found in power electronics—where the system's behavior switches discontinuously due to semiconductor switching—the PID Controller block cannot be used for automatic tuning. Instead, you can do the frequency response estimation (FRE) to obtain the characteristics of the plant, and then design a PID controller based on that.
Specifically, you can perform FRE to obtain the plant model’s FRD data, and use this data directly in the PID tuner to design your PID controller. Alternatively, you can use commands like tfest to first identify a transfer function and then design the PID controller.
For more information on FRE, please refer to the following site:
For methods on designing PID controllers using FRD (frequency response) data, the following site will be helpful:
