Abstract: A controller controls a balancer circuit, and is configured to: determine a difference value between a first DC link voltage value across a first DC link of a power converter and a second DC link voltage value across a second DC link of the power converter; determine a phase-angle and a magnitude of the difference value for an integer harmonic of a predetermined grid frequency; and provide a switching signal for switching between the first DC link and the second DC link based on the phase-angle and the magnitude. The controller is also configured to control a mid-point current at a mid-point terminal of the power converter in terms of magnitude and direction based on the switching signal.

Abstract: The technology of this application relates to a partial power converter that is configured to be connected to at least one photovoltaic panel as inputs and a direct current output bus, the at least one photovoltaic panel generating a direct current. The partial power converter includes a photovoltaic-side converter comprising at least two switching cells, a bus-side converter comprising at least two switching cells, the bus-side converter being configured to switch a total current of the photovoltaic-side converter, an energy storage element connected between the photovoltaic-side converter and the bus-side converter, and an indirect voltage source configured to regulate the energy storage element. The photovoltaic-side converter, the bus-side converter and the energy storage element are connected in parallel between the first node and the second node of the partial power converter.

Abstract: A power electronics multilevel converter comprises one or more phase legs. Each respective phase leg of the one or more phase legs comprises a plurality of cells. Each respective cell of the plurality of cells comprises an alternating current (AC)/direct current (DC) converter, a closed-loop control and a DC/DC converter. The closed-loop control is configured to regulate the cell power transmitted by the AC/DC converter to a DC link of the respective cell in accordance with a cell power reference. The cell power reference depends on a cell voltage reference. The closed-loop control is further configured to adjust the cell voltage reference in dependence of a cell power reference deviation from an average power per cell. The average power per cell depends on the cell power references of the plurality of cells of all phase legs.

Abstract: The present disclosure relates to a controller for controlling a power electronics converter in an electric distribution grid for distributing electrical energy, wherein the controller is configured to determine a first estimate of a grid voltage based on a converter current of the power electronics that the power electronics converter is capable of receiving in a passive operation mode, determine an operation mode of the power electronics converter, and upon determining a transition state of the power electronics converter in which the power electronics converter is transiting from the passive operation mode into an active operation mode, the controller is configured to determine a second estimate of the grid voltage based on the determined first estimate of the grid voltage and a converter current of the power electronics converter being receivable by the power electronics converter in the transition state upon a basis of a closed control loop.

Abstract: The technology of this application relates to an arrangement for electric power conversion and dual electric drive, a system comprising the arrangement, a method of operating the arrangement, and a computer program for carrying out the method, which enable charging of dual-drive electric vehicles (EV) from a three-phase power grid without producing any torque, while making use of all the power electronics already existing for the traction system and the motor inductances. As such, space is saved and power density, efficiency and reliability are increased.

Abstract: An arrangement for electric power conversion and an electric drive comprises a power converter that includes three legs, an electric motor including three open-end stator windings respectively having first and second ends, and a power switch. The first ends of the stator windings are coupled to respective legs of the three legs of the power converter, and the second ends of the stator windings are coupled together and have a same electric potential. The power switch is configured to selectively disconnect one of the second ends of the stator windings from all other second ends to establish at most two distinct electric potentials. The at most two distinct electric potentials are coupled to respective legs of a power grid interface coupled to the arrangement.

Abstract: Example unity power factor converter, (UPFC) operating methods and apparatus are described. In one example, the UPFC comprises a closed-loop control for regulation of an input current from a power grid in accordance with a reference variable for the input current. The UPFC is configured to determine amplitudes of frequency components of the input current, and establish a phase angle of the reference variable in dependence of a phase angle of a fundamental frequency component of an input voltage from the power grid and of the amplitudes of the frequency components.

Abstract: A cascaded multilevel converter is disclosed. The converter comprises a plurality of modules coupled to form a branch, each of the modules comprising a switching circuit and a DC link for supplying DC voltage to the switching circuit. The converter further comprises a controller for controlling the switching circuit of each module to generate an AC voltage in the branch, wherein the controller is configured to: determine for each module a voltage across a capacitor of the DC link of the module, determine for each module a reference power value for charging the capacitor of the DC link of the module to a reference voltage value for the module, determine, from the reference power values of the modules, a common reference AC current value for AC current in the branch, determine, from the common reference AC current value, a common reference AC voltage value for AC voltage in the branch.