LQR Based Optimal PID Control for Buck Converter

Abstract:

An optimization of PID controller based on indices of linear quadratic state and integration of error (IE) for Buck system is proposed. The optimal original disturbance suppression can be settled well by linear quadratic regulator (LQR) method, while assignment its weighted matrix Q and R is a matter. On the state space description of typical 2-order system, the equations among diagonal weighted matrix, parameters of PID, and characteristics of closed loop system have been established. With this, the steady, rapid and accurate nature of control system are expressed explicitly with the weighting matrix, and optimization of integral error can be easily solved due to integral velocity with constraint of given damping ratio. At last, LQR based optimal control systems with various Q for Buck are simulated, and simulations show the proposed approach have the dual optimality due to disturbance suppression.

• Periodical: Applied Mechanics and Materials (Volumes 687-691)
• Pages: 3221-3226
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.687-691.3221
• Online since: November 2014
• Authors: Gong Quan Tan*, Yong Hui Chen, Lei Gu
• Keywords: Integration of Error, Linear Quadratic Regulator, Optimal Control, PID Control, Weighting Matrix

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