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The purpose of this study was to investigate the impact of voltage drop of a three-phase voltage source inverter on driving brushless motors. This study also proposes an enhanced field-oriented control scheme that accounts for inverter voltage drop, enabling efficient driving at very low motor speeds. Experimental results are provided to verify the theoretical study and the proposed control scheme. [ABSTRACT FROM AUTHOR]

Inverters are playing an increasingly important role in the electrical utility grid due to the proliferation of renewable energy sources. Obtaining inverter models with accurate parameters is, therefore, essential for grid studies and design. In this paper, a methodology to estimate the output impedance and parameters of a residential grid-tied inverter is proposed. The methodology is first verified through simulation. A sensitivity analysis is conducted to determine the influence of the filter and controller parameters on the output impedance of the inverter. The simulated output impedance, voltage, and current are used in a parameter estimation methodology to obtain filter and controller parameters. It is shown that up to seven parameters can be estimated accurately. The proposed methodology is further investigated through a practical experiment. Two perturbation sources, the pseudo-random binary sequence perturbation and pseudo-random impulse sequence perturbation, are used, in turn, to perturb a residential grid-tied inverter that delivers up to 1.6   k W with the aim of obtaining its output impedance. The output impedances obtained through both pseudo-random sources are compared. It is shown that a pseudo-random binary sequence perturbation source applied in series between the grid and the inverter under test allows for the best estimation of the grid-tied inverter's output impedance. A black-box modeling approach aimed at estimating an analytical transfer function of the output impedance from experimental data is also discussed. [ABSTRACT FROM AUTHOR]

In some applications, where it is not necessary to ensure a constant power supply, it is possible to use photovoltaic systems without batteries. A typical application is the pumping water and subsequent use or for water desalination and storage for later use. Due to the absence of batteries, it is important to carry out an adequate sizing of each part of the system for the correct functioning of the system. This paper presents the modeling of single-phase full bridge inverter for grid isolated photovoltaic systems without the use of batteries for electrical energy storage. The function of the inverter is to take the energy from the photovoltaics modules and deliver it to an ac load, in which the delivered power will be variable due to the fact that storage batteries are not contemplated. The paper focuses on the procedure for obtaining a low frequency averaged model to analyze the effect of the current ripple on the input capacitor for the correct dimensioning of the capacitive filter. Simulation results are shown to validate the presented analysis. [ABSTRACT FROM AUTHOR]

The grid interlinked type inverter is a device that can efficiently transmit electricity through the conversion of power electronic systems. It would be advantageous to make use of various forms of renewable energy when considering the transmission of electric power. The prediction based on numerical simulations will be helpful in the development for the understanding and design of power electronic systems, predictive controller, power flow, stability, power quality analysis of the grid interlinked type inverter. This paper seeks to present a new technique examining the grid interlinked type inverter when creating a model of a nonlinear system identification through the use of nonlinear autoregressive exogenous inputs - wavelet neural network (NLARX-WNN). The NLARX-WNN was able to demonstrate the modeling approach needed for a single phase grid interlinked type microhydropower inverter. In addition, the model has estimated the optimal set of parameters via the bat search algorithms (BA). The tests of microhydro electric type inverter is performed and its model is defined. The simulated results made the NLARX-WNN solution, which was estimated with the BA, capable of the proposed scheme and this may serve to improve the accuracy of estimation when assessing the behaviour of the single phase grid interlinked type inverter. Once completed, the mathematical model can represent the system for analysing and identifying the characteristics of an electrical power system. [ABSTRACT FROM AUTHOR]

With the increasing demand for electric vehicles, the requirements of the market are changing ever faster. Therefore, there is a need to improve the electric car’s design time, where simulations could be an appropriate tool for this task. In this paper, the modeling and simulation of an inverter for an electric vehicle are presented. Four different modeling approaches are proposed, depending on the required simulation speed and accuracy in each case. In addition, these models can provide up to 150 different electric modeling and three different thermal modeling variants. Therefore, in total, there were 450 different electrical and thermal variants. These variants are easily selectable and usable and offer different options to calculate the electrical parameters of the inverter. Finally, the speed and accuracy of the different models were compared and the obtained results presented.

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