Linear Optimal Feedback and Load‐decoupled Control of a Buck Dc‐dc Converter

Abstract

This paper describes a new controller design procedure and tuning method for a PWM buck dc‐dc converter. First, linear optimal feedback is designed using the LQR approach. Then the designed control law is implemented using a PID controller incorporated with a load‐decoupled PD compensator. The PID controller is tuned to achieve the optimal design based on the output error voltage directly, instead of using an estimator. When the proposed PD compensator is used, the converter is robust with respect to the input voltage and output current changes and the parameter perturbations. We also provide the conditions for the robust stability assurance of the closed‐loop system.

Voltage Regulation of a Buck Boost Converter—a Hybrid Control Approach

“…and the power diode, respectively. Of these, q 4 can not occur in the normal working of the converter and, hence, does not appear in the set of feasible discrete states. Therefore, the set of feasible discrete states is, Q = (q 1 , q 2 , q 3 ) and the possible set of events is…”

“…The control of DC-DC converters has been extensively dealt with for more than three decades [1][2][3][4][5][6][7][8][9][10][11][12][13]. The modeling and control of these hybrid circuits are normally done either in the continuous time domain or in the discrete time domain, due to the scarcity of methods in control theory to deal with a situation where the system has interact-ing continuous and discrete time dynamics.…”

“…The modeling and control of these hybrid circuits are normally done either in the continuous time domain or in the discrete time domain, due to the scarcity of methods in control theory to deal with a situation where the system has interact-ing continuous and discrete time dynamics. The conventional approach in this regard has been the state space averaging technique, followed by linearization to get a continuous time equivalent model for the system [1][2][3][4]. The continuous model enables one to use conventional frequency domain methods to design a controller.…”

Passivity‐based control for large‐signal stability of high‐order switching converters

“…Also, the control signal, or duty cycle, is constrained in the [0, 1] interval. Basic DC-DC converter topologies, i.e.…”

“…Amongst them, Fei-Hu [1] described an LQR control of a buck converter where the design is independent of the load. Some of them have reported linear optimal controllers in DC-DC converters.…”