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Finite control set model predictive control is an emerging technique for the control of power electronic converters. This paper introduces a simple and efficient predictive torque control (PTC) algorithm for induction motor drive. The proposed technique eliminates the need for flux-weighting factor for the conventional PTC. As a result, tedious offline tuning is no longer required. At the same time, the proposed technique ensures that the relative importance between torque and flux ripples is determined in an online fashion. Moreover, unlike the conventional method that needs to evaluate the cost function seven times (for two-level three-phase inverter case), the proposed method needs only to test four voltage vectors at each control sample which leads to a significant reduction in the computation time and switching frequency without sacrificing the performance. The effectiveness of the proposed method is demonstrated by both simulation and experimental results with comprehensive comparisons with the reported literature. [ABSTRACT FROM AUTHOR]

This paper proposes a light, flexible, and yet reliable multiparametric estimation algorithm for grid-connected voltage-source-converter-based systems. This approach combines the nonlinear least squares (NLSQ) fitting algorithm and the steady-state extended harmonic domain (EHD) model to take into account the harmonic effects. The EHD model is used to take advantage of the harmonic content of the electrical signals to provide robustness and improved performance to the NLSQ estimation methodology. In addition, this harmonic formulation reduces the necessity of synchronized measurements. Details of the implementation are provided by an experimental case study, in which the grid equivalent (Thevenin voltage, inductance, and resistance), the ac-side filter (inductance and resistance), and the converter switching and conduction loss resistance are accurately estimated for three different operating conditions. [ABSTRACT FROM AUTHOR]

This paper presents a new concept in active damping techniques using a reduced model of an LCL -filtered grid-connected inverter. The presence of the LCL filter complicates the design of the inverter control scheme, particularly when uncertainties in the system parameters, especially in the grid inductance, are considered. The proposed control algorithm is addressed to overcome such difficulties using a reduced model of the inverter in a state observer. In this proposal, two of the three state variables of the system are obviated from the physical inverter model, and only the inverter-side current is considered. Therefore, the inverter-side current can be estimated emulating the case of an inverter with only one inductor, thus eliminating the resonance problem produced by the LCL filter. Besides, in the case of a distorted grid, the method allows us to estimate the voltages at the point of common coupling free of noise and distortion without using any phase-locked loop based synchronization algorithm. This proposal provides the following features to the closed-loop system: first, robust and simple active damping control under system parameters deviation; second, robustness against grid voltage unbalance and distortion; and third, an important reduction in the computational load of the control algorithm, which allows us to increase the switching frequency. To complete the control scheme, a theoretical stability analysis is developed considering the effect of the observer, the system discretization, and the system parameters deviation. Experimental and comparative evaluation results are presented to validate the effectiveness of the proposed control scheme. [ABSTRACT FROM PUBLISHER]

This paper presents evaluations among the most usual maximum power point tracking (MPPT) techniques, doing meaningful comparisons with respect to the amount of energy extracted from the photovoltaic (PV) panel [tracking factor (TF)] in relation to the available power, PV voltage ripple, dynamic response, and use of sensors. Using MatLab/Simulink and dSPACE platforms, a digitally controlled boost dc–dc converter was implemented and connected to an Agilent Solar Array E4350B simulator in order to verify the analytical procedures. The main experimental results are presented for conventional MPPT algorithms and improved MPPT algorithms named IC based on proportional–integral (PI) and perturb and observe based on PI. Moreover, the dynamic response and the TF are also evaluated using a user-friendly interface, which is capable of online program power profiles and computes the TF. Finally, a typical daily insulation is used in order to verify the experimental results for the main PV MPPT methods. [ABSTRACT FROM PUBLISHER]