Abstract: A method for operating an electrical converter including: determining an optimized pulse pattern from a fundamental voltage reference for the electrical converter, wherein the optimized pulse pattern is determined from a first lookup table and includes discrete voltage amplitude values changing at predefined switching instants; determining a harmonic content reference from the fundamental voltage reference based on a second lookup table, wherein the harmonic content reference is a harmonic current reference determined from the frequency spectrum of a current of the electrical converter or the harmonic content reference is a filtered voltage reference determined by applying a first order frequency filter to a voltage, which current or voltage is generated, when the optimized pulse pattern is applied to the electrical converter; determining a harmonic content error from the harmonic content reference by subtracting an estimated output voltage and/or estimated output current of the electrical converter from the

Abstract: A method for controlling a modular converter connected to an electrical grid for active power filtering the electrical grid to compensate for a load connected to the electrical grid, comprises: receiving an actual load current and an actual converter state of the modular converter; determining, from the actual load current and a history of previous load currents, a sequence of future load currents over a prediction horizon; predicting a sequence of future converter states of the modular converter and a sequence of manipulated variables for the modular converter over the prediction horizon by solving an optimization problem based on the actual converter state and the future load currents by minimizing an objective function mapping control objectives to a scalar performance index subject to the dynamical evolution of a prediction model of the modular converter and subject to constraints; and applying a next switching state, which is determined from a first element of the sequence of manipulated variables, to th

Abstract: A method for controlling a three-phase electrical converter comprises: selecting a three-phase optimized pulse pattern from a table of pre-computed optimized pulse patterns based on a reference flux; determining a two-component optimal flux from the optimized pulse pattern and determine a one-component optimal third variable; determining a two-component flux error from a difference of the optimal flux and an estimated flux estimated based on measurements in the electrical converter; determining a one-component third variable error from a difference of the optimal third variable and an estimated third variable; modifying the optimized pulse pattern by time-shifting switching instants of the optimized pulse pattern such that a cost function depending on the time-shifts is minimized, wherein the cost function comprises a flux error term and a third variable error term, wherein the flux error term is based on a difference of the flux error and a flux correction function providing a flux correction based on the ti

Abstract: A method for operating an electrical converter including: determining an optimized pulse pattern from a fundamental voltage reference for the electrical converter, wherein the optimized pulse pattern is determined from a first lookup table and includes discrete voltage amplitude values changing at predefined switching instants; determining a harmonic content reference from the fundamental voltage reference based on a second lookup table, wherein the harmonic content reference is a harmonic current reference determined from the frequency spectrum of a current of the electrical converter or the harmonic content reference is a filtered voltage reference determined by applying a first order frequency filter to a voltage, which current or voltage is generated, when the optimized pulse pattern is applied to the electrical converter; determining a harmonic content error from the harmonic content reference by subtracting an estimated output voltage and/or estimated output current of the electrical converter from the

Abstract: An electrical converter is interconnected via a filter with an electrical load or an electrical power source.

Abstract: A method for controlling an electrical converter comprises the acts of determining an error value based on a difference between an estimated output value and a reference output value, the estimated output value being based on measurements in the electrical converter; comparing the error value with an error band and in the case of the error value exceeds the error band, controlling the electrical converter by switching to a different control scheme. The converter is controlled with the modified pre-calculated switching by determining a pre-calculated switching sequence for the converter based on an actual state of the electrical converter, the switching sequence comprising a sequence of switching transitions of the converter; modifying the pre-calculated switching sequence by modifying transition times of switching transitions of the pre-calculated switching sequence, such that the error value is minimized; and applying at least a part of the modified switching sequence to the electrical converter.

Abstract: An exemplary electrical converter includes a plurality of semiconductor switches. The electrical converter is configured for generating a two-level or multi-level output voltage from an input voltage by switching the plurality of semiconductor switches. A method for controlling the electrical converter includes receiving a reference electrical quantity (iS*) and an actual electrical quantity (iS), determining a sequence of future electrical quantities of the electrical converter from the actual electrical quantity, determining a maximal cost value based on the sequence of future electrical quantities, and iteratively determining an optimal switching sequence for the electrical converter. A switching sequence includes a sequence of future switching states for the semiconductor switches of the electrical converter. The method also includes selecting the first switching state of the optimal switching sequence as the next switching state (u) to be applied to the semiconductor switches of the electrical converter.

Abstract: A method for controlling a modular converter connected to an electrical grid for active power filtering the electrical grid to compensate for a load connected to the electrical grid, comprises: receiving an actual load current and an actual converter state of the modular converter; determining, from the actual I load current and a history of previous load currents, a sequence of future load currents over a prediction horizon; predicting a sequence of future converter states of the modular converter and a sequence of manipulated variables for the modular converter over the prediction horizon by solving an optimization problem based on the actual converter state and the future load currents by minimizing an objective function mapping control objectives to a scalar performance index subject to the dynamical evolution of a prediction model of the modular converter and subject to constraints; and applying a next switching state, which is determined from a first element of the sequence of manipulated variables, to

Abstract: A modular converter having a plurality of converter modules for converting an input voltage into an output voltage to be supplied to a load by receiving a control input reference vector, a control input vector and a control input parameter vector; determining a control output reference vector from the control input reference vector, the control input vector and the control input parameter vector in a first control stage; and controlling the converter modules by generating switching signals based on the control output reference vector in a further control stage.

Abstract: A method for controlling a modular converter with a plurality of converter modules includes: selecting possible future switching sequences of the converter based on an actual converter switching state; predicting a future current trajectory for each switching sequence based on actual internal currents and on actual internal voltages; and determining candidate sequences from the switching sequences, wherein a candidate sequence is a switching sequence with a current trajectory that respects predefined bounds with respect to a reference current or, when a predefined bound is violated, moves the current closer to such a predefined bound. The method includes predicting future module voltages for each candidate sequence; evaluating a cost function for each candidate sequence; and selecting the next converter switching state as a first converter switching state of a candidate sequence with minimal costs.

Abstract: A method for controlling an electrical converter comprises the acts of determining an error value based on a difference between an estimated output value and a reference output value, the estimated output value being based on measurements in the electrical converter; comparing the error value with an error band and in the case of the error value exceeds the error band, controlling the electrical converter by switching to a different control scheme. The converter is controlled with the modified pre-calculated switching by determining a pre-calculated switching sequence for the converter based on an actual state of the electrical converter, the switching sequence comprising a sequence of switching transitions of the converter; modifying the pre-calculated switching sequence by modifying transition times of switching transitions of the pre-calculated switching sequence, such that the error value is minimized; and applying at least a part of the modified switching sequence to the electrical converter.

Abstract: An electrical converter is interconnected via a filter with an electrical load or an electrical power source.

Abstract: In a method based on the MPDTC algorithm for controlling an inverter of an electrical system, the harmonics and resonances in the inverter can be damped by extracting frequency information from predicted data of the MPDTC algorithm and by damping harmonic distortion of the electrical system by reintroducing the extracted frequency information into a control loop of the inverter.

Abstract: A modular converter having a plurality of converter modules for converting an input voltage into an output voltage to be supplied to a load by receiving a control input reference vector, a control input vector and a control input parameter vector; determining a control output reference vector from the control input reference vector, the control input vector and the control input parameter vector in a first control stage; and controlling the converter modules by generating switching signals based on the control output reference vector in a further control stage.

Abstract: An exemplary electrical converter includes a plurality of semiconductor switches. The electrical converter is configured for generating a two-level or multi-level output voltage from an input voltage by switching the plurality of semiconductor switches. A method for controlling the electrical converter includes receiving a reference electrical quantity (iS*) and an actual electrical quantity (iS), determining a sequence of future electrical quantities of the electrical converter from the actual electrical quantity, determining a maximal cost value based on the sequence of future electrical quantities, and iteratively determining an optimal switching sequence for the electrical converter. A switching sequence includes a sequence of future switching states for the semiconductor switches of the electrical converter. The method also includes selecting the first switching state of the optimal switching sequence as the next switching state (u) to be applied to the semiconductor switches of the electrical converter.

Abstract: A method for controlling a modular converter with a plurality of converter modules includes: selecting possible future switching sequences of the converter based on an actual converter switching state; predicting a future current trajectory for each switching sequence based on actual internal currents and on actual internal voltages; and determining candidate sequences from the switching sequences, wherein a candidate sequence is a switching sequence with a current trajectory that respects predefined bounds with respect to a reference current or, when a predefined bound is violated, moves the current closer to such a predefined bound. The method includes predicting future module voltages for each candidate sequence; evaluating a cost function for each candidate sequence; and selecting the next converter switching state as a first converter switching state of a candidate sequence with minimal costs.

Abstract: A modular converter having a plurality of converter modules for converting an input voltage into an output voltage to be supplied to a load by receiving a control input reference vector, a control input vector and a control input parameter vector; determining a control output reference vector from the control input reference vector, the control input vector and the control input parameter vector in a first control stage; and controlling the converter modules by generating switching signals based on the control output reference vector in a further control stage.

Abstract: To minimize switching losses in a rotating electrical machine, exemplary embodiments of the present disclosure proposes an iterative control method which calculates optimal switching states in advance. A rotating electrical machine can be controlled on the basis of this iterative control method.

Abstract: Exemplary embodiments are directed to a converter for an electrical system that is controlled in such that switching sequences for the converter, determined with respect to an optimization goal are modified such that by correcting a flux error resulting from assumptions on which the first optimization of the switching sequence is based.

Abstract: A method is provided for predicting pulse width modulated switching sequences for a multi-phase multi-level converter. With a first predicted switching sequence, due to multi-phase redundancies, equivalent switching sequences are determined. From the equivalent switching sequences, one switching sequence optimal with respect to a predefined optimization goal is selected. The selected switching sequence is used to switch the converter.