Design of Feedback Linearization Controller for Boost Circuit Considering Digital Quantization

Boost circuits have different small-signal linearization models at various steady-state operating points. Traditional control methods involve designing a PI controller based on a specific operating point, making it challenging to achieve comprehensive control across all operating conditions. However, in the field of nonlinear control, feedback linearization can be employed to achieve control effectiveness across different operating points. This paper initially establishes an affine nonlinear model for the Boost circuit, employing an inductor current indirect feedback linearization control strategy. This achieves feedback linearization control of the current loop independent of the converter operating point. When using digital control, the impact of digital quantization on controller parameters is considered. Controller parameters applicable directly to digital control systems are derived and analyzed. Experimental results demonstrate that, compared to traditional PI control, the feedback linearization control exhibits faster current loop response, lower overshoot, and independence of controller performance from converter operating points.