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Finite Control Set Model Predictive Control (FCS-MPC) is an alternative to conventional linear controllers in power converters due to its attractive properties such as its conceptual simplicity, flexibility, direct consideration of non linearities as well as constraints, and fast control response. This last feature imposes computational constraints and short prediction horizons are therefore needed. In fact, in many applications an horizon one FCS-MPC controller is used. However, using FCS-MPC with a short prediction horizon in topologies that exhibit non-minimum phase behavior such as active-front-end rectifiers, dc-dc boost converters, and Z-source converters, among others, may lead to control issues. This work studies the origin of these control issues using nonlinear control theory considering a dc-dc boost converter as a case study. It is shown that the difficulty to directly control the converter output voltage using short horizon FCS-MPC is the resulting unstable internal dynamic, as the short horizon FCS-MPC controller acts like an input-output linearizing controller. To solve the problem of the unstable internal dynamic, a short horizon FCS-MPC controller based on input-state linearization is proposed allowing correct operation of the system. Experimental results show the feasibility of the proposal. [ABSTRACT FROM AUTHOR]

This work proposes a multicell topology based on current-source cells in order to inherit the advantages of current-source topologies such as reduced load dv/dt voltage and natural bidirectional power flow and to adopt a similar behavior of the multicell topology based on a voltage source converter such as voltage controlled behavior where nC cells are connected in series to feed one load phase. In order to check the technical feasibility and performance of the proposed topology, a mathematical model is introduced and studied and key design guidelines of passive components are defined. The analysis shows the possibility of using components with a lower voltage rating than that of the classic multilevel current source topologies and allows the use of low switching frequencies in both rectifier and inverter stages while at the same time obtaining a high-quality waveform in both load voltage and converter input currents. A case of example is used to corroborate the theoretical analysis and the component design methodology, as well as the performance of the topology using a low-power prototype. [ABSTRACT FROM AUTHOR]

In this paper, the experimental validation of a predictive current control strategy for a four-leg indirect matrix converter is presented. The four-leg indirect matrix converter can supply energy to an unbalanced three-phase load while providing a path for the zero sequence load. The predictive current control technique is based on the optimal selection among the valid switching states of the converter by evaluating a cost function, resulting in a simple approach without the necessity for modulators. Furthermore, zero dc-link current commutation is achieved by synchronizing the state changes in the input stage with the application of a zero-voltage space vector in the inverter stage. Simulation results are presented and the strategy is experimentally validated using a laboratory prototype. [ABSTRACT FROM AUTHOR]

An asymmetric inverter features different dc-link voltages for each power cell and depending on the dc voltage ratios, there are binary, trinary, etc., asymmetric topologies. In particular, the trinary one can provide a waveform with 3^n levels, where n is the number of cells connected in cascade. Hence, for $n = 3$, an output voltage with 27 levels can be obtained, ensuring a low total harmonic distortion (THD) and reduced $dv/dt$. However, when the load consumes active power, some power cells of the inverter can operate in regeneration mode, complicating the topology and control. To overcome this problem, a new modulation method for asymmetric inverters is presented. It features an ac output voltage of 13 levels for $n = 3$, and ensures unidirectional power flow in every power cell. This new modulation method also provides a voltage waveform with low $dv/dt$ and reduced THD (5.7%). To confirm the approach, power flow and sensitivity analysis to changes in the dc voltage ratios are performed. Finally, simulation and experimental results are provided. [ABSTRACT FROM PUBLISHER]

This paper presents the implementation of a predictive control scheme for an indirect matrix converter. The control scheme selects the switching state that minimizes the reactive power and the error in the output currents according to their reference values. This is accomplished by using a prediction horizon of one sample time and a very intuitive control law. Experimental results with a 6.8-kVA indirect matrix converter prototype are provided in order to validate the proposed control scheme. The converter uses standard digital signal processor operating at a sampling frequency of 20 its. It is shown that the idea of controlling this converter topology with a predictive approach can be implemented simply and input currents with unity power factor and a total harmonic distortion lower than 5% can be obtained. [ABSTRACT FROM AUTHOR]