Hector A. Young

State of the Art of Finite Control Set Model Predictive Control in Power Electronics

This paper addresses to some of the latest contributions on the application of Finite Control Set Model Predictive Control (FCS-MPC) in Power Electronics. In FCS-MPC , the switching states are directly applied to the power converter, without the need of an additional modulation stage. The paper shows how the use of FCS-MPC provides a simple and efficient computational realization for different control objectives in Power Electronics. Some applications of this technology in drives, active filters, power conditioning, distributed generation and renewable energy are covered. Finally, attention is paid to the discussion of new trends in this technology and to the identification of open questions and future research topics.

Model Predictive Control: A Review of Its Applications in Power Electronics

Model-based predictive control (MPC) for power converters and drives is a control technique that has gained attention in the research community. The main reason for this is that although MPC presents high computational burden, it can easily handle multivariable case and system constraints and nonlinearities in a very intuitive way. Taking advantage of that, MPC has been successfully used for different applications such as an active front end (AFE), power converters connected to resistor inductor RL loads, uninterruptible power supplies, and high-performance drives for induction machines, among others. This article provides a review of the application of MPC in the power electronics area.

Assessing Finite-Control-Set Model Predictive Control: A Comparison with a Linear Current Controller in Two-Level Voltage Source Inverters

Model predictive control (MPC) methods for applications in power converters have received considerable attention in recent years. The idea behind MPC is to use a mathematical model of the system to predict its future behavior within a predefined time. An optimization problem that includes the control objectives, the predicted variables, and possible constraints of the system is solved, yielding the control actions to be applied.

Model Predictive Control: MPC's Role in the Evolution of Power Electronics

The evolution of power electronics and its control has been mainly driven by industry applications and influenced by the development achieved in several technologies, such as power semiconductors, converter topologies, automatic control, and analog and digital electronics. Digital signal processors (DSPs), in particular, have experienced an exponential development in processing power, which until now has not been fully exploited for control purposes in power converters and drive applications. Presently, the control system technology finds itself in a paradigm-changing tipping point, in which more demanding control goals, system flexibility, and functionalities required by emerging applications are driving the control system technology development, in addition to stabilization and robustness, which was the main focus in the past. This article walks briefly through the history of the mainstream power converter control scene, with an emphasis on the more recent introduction of predictive control, and gives a glimpse on the challenges and possibilities ahead. Special attention is given to finite control set (FCS)-model predictive control (MPC), because of its simplicity, flexibility, inherent adaptation to power electronic circuits and their discrete nature, both in the finite amount of switching states and the digital implementation with microprocessors.

Analysis of Finite-Control-Set Model Predictive Current Control With Model Parameter Mismatch in a Three-Phase Inverter

It is well known that predictive control methods can be affected by the presence of modeling errors. The extent to which finite-control-set model predictive control (FCS-MPC) is influenced by parametric uncertainties is a recurrent concern at the moment of evaluating the viability of this method for power electronics applications. This paper proposes an analytic approach to examine the influence of model parametric uncertainties on the prediction error of FCS-MPC for current control in a three-phase two-level inverter. The analysis shows that the prediction error is not only determined by parametric mismatch but also by the instantaneous values of load current and inverter output voltage. This implies that within each sampling period of the predictive algorithm several conditions of prediction error are generated, as multiple voltage vectors are evaluated. Simulation and experimental results are provided and discussed showing the effects of inaccuracies in the modeling of load resistance and inductance parameters on the performance of FCS-MPC. Even though steady-state performance is noticeably affected with parameter changes, especially when the load inductance is overestimated by the model, its fast transient step response is less affected by parameter changes.

Full electric ship propulsion based on a flying capacitor converter and an induction motor drive

Modern ship propulsion systems are looking towards to high efficiency electric drive systems. The present paper presents the dynamic behaviour of a naval Full Electric Propulsion (F.E.P.) system based on a Flying Capacitor Multilevel Inverter and an Induction Motor Drive. Simulation results based on real hull dynamic data where carried out for load loss, load impact and speed reversion.

Comparison of finite-control-set model predictive control versus a SVM-based linear controller

In recent years, Finite Control Set Model Predictive Control (FCS-MPC) has received considerable attention due to advantages such as ease of implementation, flexibility in the definition of control objectives and superior transient performance. However, some drawbacks of FCS-MPC, such as variable switching frequency and steady-state error, have also been reported. In order to assess the performance of FCS-MPC, this paper presents a comprehensive comparison of this method and a synchronous PI controller with space vector modulation (PI-SVM) for current regulation in steady-state and transient operation. The parameters of the linear controller are designed according to the modulus optimum technique, in order to guarantee a fast transient response. Quantitative performance indices are applied to both control schemes in a wide range of operating points of the inverter. In simulation results, the steady-state performance of FCS-MPC is strongly influenced by the operating point. As for the transient response, the FCS-MPC is slightly faster than the PI-SVM, also offering a better decoupling capability between the d and q axes of the current.

Nine-switch converter application on electric ship propulsion — A redundancy approach

Currently used inverter solutions for ship propulsion applications are based in classic voltage source inverter (VSI) topologies, mostly two-level voltages source inverters (2L-VSI) and cascaded H-Bridge voltage source inverters (CHB-VSI) which have became a standard as from the industrial point of view. Nevertheless, modern ship propulsion applications are required to operate under faulty conditions, demanding power electronics to ensure redundancy capability. This work presents a redundant converter topology based on a nine-switch inverter, for its application in electric-propelled ships.

A commercial-off-the-shelf synchronous reluctance motor as a generator for wind power applications

This paper studies the feasibility of the use of a synchronous reluctance machine (SynRM), working as a generator, in a wind power generation system. The main goal of this research is to develop a reliable and inexpensive alternative for power generation with no rare-earth materials and good performance and efficiency. A full-power back-to-back converter is used to inject the converted energy into the utility. This configuration allows to supply the SynRM with the required reactive power and to manage the speed variations due to the wind. An operating mode selector is developed to provide a wide speed range of operation. The analysis is carried out based on the models and parameters of an actual commercial-off-the-shelf (COTS) SynRM and a wind turbine prototype. Numerical simulation shows that the synchronous reluctance machine can operate satisfactorily converting energy in the whole wind speed range that is tolerable by the turbine.