A Digital Dual-Mode Lqr Optimal Controller For Boost Converter Over A Wide Operation Range

A new dual-mode discrete-time linear quadratic regulator (LQR) optimal controller is presented, which allows voltage control of a boost converter for wide-load-range condition, whether in continuous conduction mode (CCM) or in discontinuous conduction mode (DCM). A linear quadratic regulator (LQR) controller combined with kalman filter is designed for the voltage control of boost converter. Feedback gain and estimator gain can be calculated offline based on LQR steady-state optimal control method and steady-state kalman filter. Different control gains calculated based on plant models will be obtained since the modeling of DC-DC converters in CCM and DCM are different. The proposed control strategy makes it possible for boost converter to autonomously operate in CCM or DCM control gain by utilizing a mode detector. The proposed mode detector greatly enhances the control performance in different operating mode, even at the boundary condition. Finally, the proposed controller has been implemented on NI CompactRio platform for boost converter voltage control. The experimental results clearly show the proposed controller offers better performance in both transient response and frequency response.