Jesús Linares-Flores

On the Control of the Permanent Magnet Synchronous Motor: An Active Disturbance Rejection Control Approach

This brief presents an active disturbance rejection control scheme for the angular velocity trajectory tracking task on a substantially perturbed, uncertain, and permanent magnet synchronous motor. The presence of unknown, time varying, and load-torque inputs, unknown system parameters, and the lack of knowledge of the initial shafts angular position, prompts a high-gain generalized proportional integral (GPI) observer-based active disturbance rejection (ADR) controller. This controller is synthesized on the basis of the differential flatness of the system and the direct measurability of the systems flat outputs, constituted by the motors angular displacement and the d-axis current. As a departure from many previous treatments, the d-q-axis currents model is here computed on the basis of the measured displacement and not on the basis of the unknown position. The proposed high-gain GPI observer-based ADR controller is justified in terms of a singular perturbation approach. The validity and robustness of the scheme are verified by means of realistic computer simulations, using the MATLAB/SIMULINK-PSIM package.

Load Torque Estimation and Passivity-Based Control of a Boost-Converter/DC-Motor Combination

An algebraic approach is presented for the fast feed-forward adaptation of the angular velocity trajectory tracking task in a Boost-converter driven dc-motor system. For the adaptation, the load torque perturbations are assumed piecewise constant and are, nonasymptotically, online estimated using the available noisy measurements of the state variables. The controller is a linear controller based on the exact tracking error dynamics passive output feedback (ETEDPOF) controller design methodology including suitable adaptive feed-forward precompensation depending explicitly on the precisely estimated torque. The performance of the adaptation, which is achieved by means of the algebraic online-estimation of the current unknown load torque, is successfully validated in an experimental laboratory setup.

Robust Nonlinear Adaptive Control of a “Boost” Converter via Algebraic Parameter Identification

This paper presents the design of a robust nonlinear adaptive controller for trajectory tracking maneuvers of the nonminimum phase output voltage on a dc-to-dc “boost” power converter with uncertain time-varying parameters. The unknown parameter variations concern both the resistive load and the input voltage supply value. A generalized proportional-integral (GPI) indirect control, exploiting the flatness property of the system, performs fast adaptations on the feedback controller and on the desired output reference trajectory owing to a fast online algebraic parameter identification procedure. The required updating of the algebraic parameter identification process is periodically triggered to cope with the time variations of the unknown plant parameters. The proposed control scheme is shown to be quite effective for handling the significant plant uncertainties when tested through experiments on a laboratory prototype. An adaptive linear quadratic regulator optimal control based on feedback linearization was designed in order to compare its performance against that of the proposed GPI adaptive scheme. An integral square error index was used for the evaluation.

Robust Passivity-Based Control of a Buck–Boost-Converter/DC-Motor System: An Active Disturbance Rejection Approach

This paper presents an active disturbance rejection (ADR) approach for the control of a buck-boost-converter feeding a dc motor. The presence of arbitrary, time-varying, load torque inputs on the dc motor and the lack of direct measurability of the motors angular velocity variable prompts a generalized proportional integral (GPI) observer-based ADR controller which is synthesized on the basis of passivity considerations. The GPI observer simultaneously estimates the angular velocity and the exogenous disturbance torque input in an on-line cancellation scheme, known as the ADR control. The proposed control scheme is thus a sensorless one with robustness features added to the traditional energy shaping plus damping injection methodology. The discrete switching control realization of the designed continuous feedback control law is accomplished by means of a traditional PWM-modulation scheme. Additionally, an input to state stability property of the closed-loop system is established. Experimental and simulation results are provided.

A Comparison Between the GPI and PID Controllers for the Stabilization of a DC–DC “Buck” Converter: A Field Programmable Gate Array Implementation

This paper presents a comparison between two stabilizing average output feedback controllers implemented on a field programmable gate array (FPGA) facility. A generalized proportional integral (GPI) controller and a proportional integral derivative (PID) controller are implemented using an FPGA, and their respective performances are duly compared. The GPI controller is found to present a better dynamic response than the PID controller in terms of the settling time while exhibiting a greater degree of robustness regarding disturbance rejection represented by severe changes in static and dynamic loads. The average controllers and their corresponding pulsewidth modulation actuators are implemented using a Spartan 3E1600 FPGA.

Robust Backstepping Tracking Controller for Low-Speed PMSM Positioning System: Design, Analysis, and Implementation

This article is concerned with the design and implementation of a robust position trajectory tracking controller for a permanent magnet synchronous motor (PMSM). The information on the angular position, provided by a classical resolver, is here complemented with an observer based phase lock loop (PLL) circuit which accurately renders the position and the angular velocity of the rotor. A Backstepping control law is designed from the input-output linearization of the PMSM model, written in d-q coordinates. This controller is adapted through a load torque and friction reduced order observer to ensure high closed loop performance of the motor. An input-state stability analysis of the entire system is also provided. Co-simulation via the MATLAB/Simulink-PSIM package, including realistic measurement disturbances, are used to investigate the stability and accuracy of the proposed control algorithm. The simulation results are examined and confirmed through laboratory experiments.

Sensorless Passivity Based Control of a DC Motor via a Solar Powered Sepic Converter-Full Bridge Combination

This article deals with the sensor-less control of a DC Motor via a SEPIC Converter-Full Bridge combination powered through solar panels. We simultaneously regulate, both, the output voltage of the SEPIC-converter to a value larger than the solar panel output voltage, and the shaft angular velocity, in any of the turning senses, so that it tracks a pre-specified constant reference. The main result of our proposed control scheme is an efficient linear controller obtained via Lyapunov. This controller is based on measurements of the converter currents and voltages, and the DC motor armature current. The control law is derived using an exact stabilization error dynamics model, from which a static linear passive feedback control law is derived. All values of the constant references are parameterized in terms of the equilibrium point of the multivariable system: the SEPIC converter desired output voltage, the solar panel output voltage at its Maximun Power Point (MPP), and the DC motor desired constant angular velocity. The switched control realization of the designed average continuous feedback control law is accomplished by means of a, discrete-valued, Pulse Width Modulation (PWM). Experimental results are presented demonstrating the viability of our proposal.

A TIME-VARYING LINEAR STATE FEEDBACK TRACKING CONTROLLER FOR A BOOST-CONVERTER DRIVEN DC MOTOR

Abstract This article deals with the trajectory tracking problem for the angular velocity of a dc-motor shaft using a Boost-converter as the switch regulated electronic drive. The main result of our proposed control scheme is that measuring of the angular velocity is not really necessary and the control law is synthesized using only a linear time-varying combination of the converter current and voltage variables. The voltage reference trajectory for the converter is generated exploiting a partial differential flatness property of the combined system. The reference trajectories of the average control and the input current are calculated via stored energy considerations and planning for the initial and final stationary regimes. The discrete switching control realization of the designed continuous feedback control law is accomplished by means of a traditional PWM-modulation scheme. Experimental results are provided.

Generalized Proportional Integral Tracking Controller for a Single-Phase Multilevel Cascade Inverter: An FPGA Implementation

This paper presents a robust linear generalized proportional integral (GPI) control scheme for the output reference trajectory tracking task on a multilevel single-phase “buck” inverter. The scheme is shown to be robust with respect to arbitrary time-varying load current demands, acting as perturbation inputs to the inverter, and to significant converter parameter variations. The discrete time version of the control scheme is implemented on a field-programmable gate array hardware. Several laboratory robustness tests are performed on the controlled inverter with excellent results.

Sliding Mode-Delta Modulation GPI Control of a DC Motor through a Buck Converter

Abstract In this article, one Generalized Proportional Integral (GPI) feedback control scheme is proposed for a smooth “ starter” for a DC motor based on a switch controlled DC-to-DC power converter of the “buck” type. The dynamic feedback controller is based on a suitable combination of GPI based control, flatness and a Σ – Δ modulator implementation of the average designed controller. The scheme proposes a direct regulation of the motor shaft speed. As a consequence, the proposed feedback controller, which are not based on asymptotic observers nor calculations based on samplings, use only an optical velocity sensor. The effectiveness of the proposed controller was verified by computer simulations using the P-Spice circuit simulation program.