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Flying‐capacitor multilevel converters (FCC) need a passive or active regulation of the capacitor voltages. Recently the trend is towards active control, often implemented separately from the current control. The advantages of a true multi‐variable control sparked the interest to apply Model Based Predictive Control (MBPC) for FCC. In this paper an objective analysis method to evaluate the effects of several design choices is presented. The effects of the weight factor selection, model simplification, and prediction horizon expansion for MBPC of a 3‐level FCC are analyzed in a systematical way.

The analysis is mainly based on the mean square error (MSE) of current and capacitor voltage. The results are analysed for different lengths of the prediction horizon and for a wide range of weight factor values. Similarly the effect of a model simplification, neglecting the neutral point voltage, is studied when implementing MBPC for FCCs while considering the computational aspects. Validation of the simulation results is done by experiments on an FPGA‐based setup.

Including the effect of the neutral point voltage considerably increases the current control quality and a much wider range of good values for the weight factor exists. As this good range is not critically dependent on the current amplitude it is possible to select one weight factor value for all operating points. Furthermore, it is concluded that increasing the prediction horizon increases the computational load without improving the control quality.

The effects of increasing the prediction horizon when including other controlled variables is to be investigated, as well as the robustness to modeling errors. The MSE analysis methodology is very suitable for this further research.

For practitioners of MBPC in power electronics the paper proves that by means of simulations and the MSE one value for weight factor can be chosen for all operating points. The paper clearly shows that a practical implementation is feasible and demonstrates that neglecting the neutral point voltage is not good practice.

The MSE‐based analysis is shown to be a systematical and unbiased methodology to evaluate the effects of design choices. The results from this analysis can be directly applied in practical setups.

The flying capacitor converter (FFC) balances the clamping capacitor voltages naturally when phase shifted carrier modulation is used. Several models that describe this mechanism, and to estimate the time constants following a perturbation, are discussed in the literature. However, due to the model complexity, numerical methods must be used to evaluate these models. This paper aims to present a closed form expression, using a reference table, that describes a maximum bound for the voltage balancing time constant.

The FCC is analysed in the frequency domain. A decomposition of the characteristic matrix that describes the voltage balancing mechanism is used. The resulting real symmetric matrix is factorised by using approximations of the load characteristics at the frequencies of interest.

The minimum eigenvalue of the factorised matrix is used to determine a maximum bound for the time constant of the voltage balancing. Since the factorised matrix is independent of variations in switching frequency and load, the eigenvalue of interest can be calculated once and tabulated.

The closed form expression can be used for quick calculations of the maximum time constant under different operating conditions. Furthermore, the expression provides considerable insight into the influences circuit design choices have on the balancing mechanism.

This study aims to propose a mathematical model for stacked multicell converters (SMCs), to be exploited in the analytic determination of natural voltage balancing dynamics of the flying-capacitor (FC) stacked multicell multilevel converters, i.e. investigations of the start-up behavior, dynamic response, and natural voltage balancing phenomenon.

The crux of the proposed strategy is based on the closed-form analytic solution derivation for the switching functions used in the switching of the SMCs operated under phase disposition (PD) and phase shifted carrier (PSC) pulse width modulation (PD-PSC-PWM) technique. Hence, the suggested approach develops an analytic solution for the Fourier series and associated Fourier coefficients pertinent to the switching functions of the SMCs by obtaining the switching instants of the PD-PSC-PWM modulator in terms of Kapteyn series when the frequency of the triangular carrier waveform (fc) and that of the sinusoidal reference waveform (fr) have an integer ratio, i.e. f _c  · f _r −1=k, k∈N.

This approach results into a model, first order differential equation based model, which can be readily developed for the SMCs with any number of levels expediting the investigation of their performance. Furthermore, by an experimental scrutiny conducted on a 4×2-cell-nine-level topology of an SMC, it is inferred that under PD-PSC-PWM modulation technique, FC voltages balance naturally for higher number of stacks and cells, therefore the natural balancing exist for high-level SMCs.

Despite the sophistication of the proposed methodology and mathematical model, this study presents an alternative approach with high potential of applicability for derivation of the multilevel converter mathematical model exploiting the Kapteyn (Bessel-Fourier) series.

Numeric computation results of the proposed analytic model for the SMCs and the simulation results as well as investigational measurements taken from 2×2-cell-five-level and 4×2-cell-nine-level experimental set-ups are presented in order to substantiate the suggested approach, derived model, and verification of natural balancing.

This article and its innovations are original.

The flying capacitor converter (FFC) balances the clamping capacitor voltages naturally when phase shifted carrier modulation is used. Several models that describe this mechanism are discussed in the literature. However, due to the model complexity, the stability of the mechanism is inferred from the circuit operation. This paper aims to show that the expressions describing the balancing mechanism can be simplified and used to prove Lyapunov stability.

The FCC is analysed in the frequency domain. An equivalent circuit that describes the converter operation in terms of total and difference parameters is used. A concerted effort is made to simplify the resulting convolution expressions to their most basic forms by using the characteristics of the phase shifted switching functions' Fourier series coefficients.

It is shown that the system matrix decomposes naturally into the sum of a symmetric and a skew‐symmetric matrix. Through use of Lyapunov's theorem it is shown that the system is stable if the symmetric part of the decomposition is positive definite. A proof is provided that this matrix is positive semidefinite and the system is therefore Lyapunov stable.

The simplified expressions describing the convolution and the decomposition of the system matrix can be used in future studies to provide maximum bounds on the rebalancing time constant.

This study provides a proof that the natural voltage balancing mechanism is stable. This stability had to be inferred from circuit operation in previous studies. Secondly, the decomposition of the system matrix provides an avenue for future research.

The purpose of this paper is to implement a finite set model predictive control algorithm to a shunt (or parallel), multilevel (cascaded H-bridge) active power filter (APF). Specifically, the purpose is to get a controller that could compensate the mains current and, at the same time, to control the voltages of its capacitors. This strategy avoids the use of multiple PWM carriers or another type of special modulator, and requires a relatively low processing power.

This paper is focussed in the application of the predictive controller to a single-phase parallel APF composed for two H-bridges connected in series. The same methodology can be applied to a three-phase APF. In the DC buses of each H-bridge, a floating capacitor was connected, whose voltage is regulated by the predictive controller. The controller is composed by, first, a model for the charge/discharge dynamics for each floating capacitor and a model for the output current of the APF; second, a cost function; and third, an optimization algorithm that is able to control all these variables at the same time, choosing in each sample period the best combination of firing pulses.

The controller can track the voltage references, compensate the current harmonics and compensate reactive power with an algorithm that evaluates only the three nearest voltage levels to the last voltage level applied in the inverter. This strategy decreases the number of calculations required by the predictive algorithm. This controller can be applied to the general case of a single-phase multilevel APF of N-levels and extend it to the three-phase case without major problems.

The implemented controller, when the authors consider a constant sample time, gives a mains current with a Total Harmonic Distortion (THD-I) slightly greater in comparison with the base algorithm (that evaluates all the voltage levels). However, when the authors consider the processing times under the same processor, the implemented algorithm requires less time to get the optimal values, can get lower sampling times and then a best performance in terms of THD-I. To implement the controller in a three-phase APF, a faster Digital Signal Processor would be required.

The implemented solution uses a model for the charge/discharge of the capacitors and for the filter current that enable to operate the cascaded multilevel inverter with asymmetrical voltages while compensates the mains currents, with a predictive algorithm that requires a relatively low amount of calculations.

Studies have identified low levels of social support as one of several risk factors for poor psychological outcome following bereavement. Despite this fact, little is known about how bereaved individuals interpret and define social support or which behaviors they perceive as helpful (Cacciatore, Thieleman, Fretts, & Jackson, 2021). The present study seeks to understand the experiences of the support received by Danish families who have lost a parent to death. Individuals recruited from a mutual bereavement support group (N = 87, 25–59 years old) responded to an online survey, which yielded both quantitative and qualitative data, the latter from open-ended questions and comment boxes. The results demonstrated a variety of sources of support. However, some of the bereaved individuals also reported a decided lack of help for both adults and children post-loss. As most respondents were women (93%), future research might shed more light on possible gender differences in the expectations, needs, and experiences of social support in bereavement. The study participants provided elaborate suggestions for the improvement of bereavement support, such as, practical help, access to bereavement support groups, more knowledge on bereavement and grief in the Danish society, and easier access to peer support. The chapter revealed an apparent lack of coordination of the support for parentally bereaved families. Additionally, some groups of bereaved children seemed to be particularly vulnerable and overlooked, namely the very young children, children in late adolescence/young adulthood, and children with special needs.

To investigate different aspects of the development policies of high potentials and their relationships with organizational characteristics in a set of Belgian companies.

A set of research questions has been used to conceive a structured questionnaire to empirically investigate the different aspects of high‐potential development policies using a survey among 86 Belgian companies.

The results indicate that very often the development policies are of an ad hoc nature, but that individuals may get some say in the process. Job rotation and mentoring/coaching are quite popular activities and formal external training has the most diversified application. As expected, high‐potential development takes up more time and offers a wider scope of activities than is the case for other managerial development initiatives. Especially, organization size may bring some variation in these patterns.

The target group in this research is limited to the HR managers from the profit sector in Belgium. This is a “restricted diverse organization survey” and makes use of a non‐representative sample.

The link has been made with the “new psychological contract”. Implications for changing career planning are presented (from traditionalistic to a more “self‐directed” tendency). Also, the larger scope of development activities in an international environment and the role of management development as a “glue technology” has been elaborated on.

Most of the studies on high potentials are normative and prescriptive; very few articles have presented empirical findings on high potentials and placed them in an organizational context. Also, the specific role of development techniques in a planned international high‐potential environment has been highlighted.

The industrial robot has now become accepted in almost every sector of manufacturing industry as this review of robot applications and specifications shows.

Research in the field of openness has become very broad and, unfortunately, also opaque. Thus, the purpose of this paper was to analyse and map the trends by applying bibliometric tools to the scientific literature published between 1990 and 2015, for descriptive bibliometric analysis, and 2011 to 2015, for content analysis.

A bibliometric analysis was used to identify document types, most prolific institutions, countries, source titles and Web of Science categories in the field of openness. Furthermore, bibliometric mapping was performed to discover country and institutional cooperation networks and to be able to understand funding opportunities for openness and information technology research. Additionally, with content analysis, scientific landscape was produced with most prolific terms and their chronological evolution through time.

The first information sources were published in 1990, and production was steady until 1998. After that period, the growth becomes exponential for the total number of information sources, as well as articles and proceedings papers, with a slight decrease in growth between 2009 and 2011. Descriptive bibliometric analysis showed that the most productive countries were the USA, the UK, Germany, China, Italy and Spain.

This paper presents the first holistic bibliometric analysis of the literature production concerning openness in relation to information and communication technology which helps researchers in the field to better understand the relations between themes and outsiders to get an overview of the openness scientific landscape.