Synthesis of A Digital PID/LQR Control System for Duty-Cycle Modulation Buck Converters

Abstract

<p>This research paper presents a synthesis approach of a digital optimal PID/LQR control system for DCM (duty-cycle cycle modulation) Buck converters. The step response of the DCM Buck converter is obtained under Multisim virtual simulation framework. The related data file is saved as *.SCP format, and imported into EditPad Lite7 editor, then exported as Matlab file to be processed. The transfer function of the DCM Buck converter is computed from the imported step response data. Then, using the zoh (zero order holder) discretization method with 100 ms resampling period, the z-transfer function of the DCM Buck converter is computed, and that of the analog optimal PID/LQR(linear quadratic regulator) controller is calculated using Tustin’s discretization technique. Furthermore, the step response of the related closed loop digital PID control system is simulated and compared to that of the original analog PID/LQR control system. The simulation results obtained are presented in order to show the high precision as well as the reliability of Matlab-based synthesis of digital optimal PID/LQR control systems for DCM Buck converters.</p>

Nonlinear Time Series Analysis in Unstable Periodic Orbits Identification-Control Methods of Nonlinear Systems

“…Thus, we showed that the strength of the control could be significantly reduced by applying a perturbation with a phase difference between the perturbing signal and the sawtooth signal. Moreover, when we have phase changes in the perturbation, the system exhibits chaotic behavior and can be stabilized by exercising greater control over it [49,50].…”

Modeling and virtual simulation of the boost chopper by DCM using the optimal PIDF control

“…We propose to equip the Boost Chopper in DCM with an LQR controller with parameters , and which were initially equipped with a conventional PID corrector. The 2nd order differential equation obtained by inverse Laplace transformation is established respectively by (16) , (17) [ 26 ]: …”

“…[ 24 , 25 ] significantly reduced the THD to 2.82 %, compared with 3.12 % for control using the hysteresis approach. As regards the Buck chopper class [ 26 , 27 ], established the basis for optimizing control using the PID/LQR controller. The comparative study carried out between the analog and digital domains by discretizing the system's closed-loop transfer functions resulted in a perfect juxtaposition of the system's responses in these different domains.…”

New Speed Control Scheme for a Three-Phase Induction Machines - (3~IM) Based on Sine Duty Cycle Modulation (SDCM)

“…Relation (4) corresponds to the linearised model of defined in [12][13][14][15][16][17][18][19][20][21][22][23][24].…”

“…This technique allows efficient control of the inverter switches supplying the ASM. SRCM has several advantages [8][9][10][11][12][13][14][15][16][17][18][19][20] such as hardware simplicity, low implementation cost, attractive modulation properties, self-modulation and simple design of good quality inverters. MRC was initially introduced for industrial instrumentation applications, such as analogue-to-digital conversion (ADC) [21], digital-to-analogue conversion (DAC) [22] and analogue signal transmission [23].…”