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This article studies the model predictive control (MPC) for a twisted buck–boost inverter based on unfolding circuit. The focus is on the practical implementation of the MPC algorithm for the microcontroller designed for application in power electronics. Selection of proper cost function parameters along with a continuous control set reduced prediction horizon, at the same time keeping good quality of the grid current. The results showed that simplified differential equations and a multicore microcontroller contribute to the sample time reduction, which in turn increases the sampling frequency with the corresponding increase in the output current quality. The simulation and experimental results confirmed theoretical predictions. In conclusion, the MPC technique suits for reducing zero-crossing distortion and in applications based on unfolding circuit. [ABSTRACT FROM AUTHOR]

This paper describes a novel family of single-phase single-stage buck–boost inverters using output unfolding circuits. Operation principles and component design guidelines along with modulation techniques are presented and discussed. The simulation results confirm all theoretical statements. Experimental setup of the most promising solution is assembled and tested, where the efficiency for different operation modes is analyzed. Finally, the pros and cons along with applications of the proposed solutions are discussed in the conclusions. [ABSTRACT FROM AUTHOR]

This paper presents a novel power conditioning unit (PCU) for variable-speed micro wind turbine applications. It contains a simple generator-side rectifier, galvanic isolation with a simple dc–dc converter, and a single-phase full-bridge inverter at the grid side. Variable-speed micro wind turbines based on a permanent magnet synchronous generator (PMSG) are increasingly used in residential and small commercial buildings, despite their relatively low output voltage. Therefore, they can be used easily for battery charging, while their grid integration requires a PCU with galvanic isolation. Most of available PCUs provide no galvanic isolation, or use relatively complicated topologies or four stage energy conversion for that purpose. The dc–dc converter proposed allows reducing the complexity of the PCU. Steady-state analysis shows that the converter is capable of regulating voltage in a wide range suitable for micro wind turbines, which is supported by experimental results within the input voltage range of 40–400 V. The prototype built for integration of a 1.3-kW PMSG-based micro wind turbine shows good performance over the entire 1:5 range of the given wind turbine output voltage. A study of efficiency and power losses was conducted according to the wind turbine power profile. [ABSTRACT FROM PUBLISHER]

Impedance-source networks are an increasingly popular solution in power converter applications, especially in single-stage buck–boost power conversion to avoid additional front-end dc–dc power converters. In the survey papers published, no analytical comparisons of different topologies have been described, which makes it difficult to choose the best option. Thus, the aim of this paper is to present a comprehensive analytical comparison of the impedance-source-based buck–boost inverters in terms of passive component count and semiconductor stress. Based on the waveform of the input current, i.e., with or without a transformer, and with or without inductor coupling, the impedance-source converters are classified. The main criterion in our comprehensive comparison is the energy stored in the passive elements, which is considered both under constant and predefined high frequency current ripple in the inductors and the voltage ripple across the capacitors. Two-level and multilevel solutions are described. The conclusions provide a “one-stop” information source and a selection guide of impedance-source-based buck–boost inverters for different applications. [ABSTRACT FROM PUBLISHER]

This paper describes novel single-phase solutions with increased inverter voltage levels derived by means of a nonstandard inverter configuration and impedance source networks. Operation principles based on special modulation techniques are presented. Detailed component design guidelines along with simulation and experimental verification are also provided. Possible application fields are discussed, as well as advantages and disadvantages. Finally, future studies are addressed for the new solutions. [ABSTRACT FROM PUBLISHER]