Abstract: A coordinated control method for a distribution network with DER and EV and coordinated control system thereof includes acquiring information from at least one DER controller, at least one EV controller and/or at least one load controller; calculating P/Q references and/or circuit breaker control commands for the DER, the EV and the load based on active/reactive power balance, voltage and/or frequency requirement; allocating the references and/or the control commands to the DER, the EV and the load based on their locations and available capacity; and outputting the allocated references and/or control commands to the DER, the EV and the load. The solutions minimize negative impacts from DER and EVs and maintain a controllable voltage and frequency stabilization.

Abstract: A converter arrangement for an AC system includes a phase leg including a first sub-converter, a second sub-converter, an IPT interface configured for connecting the first and second sub-converters with a phase line A, and at least one DC bus connected to the first and second sub-converters. The first sub-converter is connected in parallel with the second sub-converter between the DC bus and the IPT interface. Each of the first and second sub-converters includes a chain-link converter connected to the IPT interface and including a plurality of converter cells connected in series with each other, and a common DC link multilevel converter connected to the DC bus and in series with the chain-link converter.

Abstract: A control system for an electric vehicle charging station (EVCS) is provided, the control system comprises: a central controller configured to receive an ancillary service order from a power grid and distribute the ancillary service order to one or more local controllers periodically; and the one or more local controllers configured to control a plurality of electric vehicle supply devices based on the distributed ancillary service order in real time. The method controlling the electric vehicle charging station (EVCS) is also provided.

Abstract: An energy storage system (ESS) for an electrical system includes an energy storage, and a converter interface arranged for connecting the energy storage to the electrical system. The converter interface includes a modular multilevel converter in which each phase leg includes a plurality of series connected cells of which at least one is a half-bridge cell and at least one is a full-bridge cell.

Abstract: A method of controlling a multilevel converter, a computer program and a controller for a converter is provided. The method includes determining a transition voltage from a control period to a following control period, analyzing the switching cells of each phase leg, selecting capacitors to provide the transition voltage and synthesize the output voltage for the following control period, and connecting the selected capacitors during the following control period. The analyzing of each switching cell includes analyzing a first switching leg and a second switching leg of the switching cell. The method includes determining whether a change of state of the first switching leg would contribute to the direction of the transition voltage, and determining whether a change of state of the second switching leg would contribute to the direction of the transition voltage, and determining the internal conditions of each of the first and the second switching leg that are determined as contributing to the transition.

Abstract: A converter arrangement and a method of controlling a three-phase converter arrangement connected to a transmission grid are provided. The converter arrangement includes three phase legs and an energy transfer circuit. The method includes providing a varying respective output phase voltage to the transmission grid by selecting energy storage elements of both the phase legs and the energy transfer circuit and connecting the selected energy storage elements to the transmission grid output. The method further includes selecting energy storage elements for performing a transfer of energy between the energy storage elements during the control period.

Abstract: A multi-level power converter includes switching cells, each comprising switching devices and an energy storage element. The switching cells include switching cells of a first type and switching cells of a second type. The converter includes, for each phase, a first arm of serial connected switching cells and a second arm of serial connected switching cells, which first arm and second arm are connected in parallel. The first arm includes more switching cells of the first type than switching cells of the second type and the second arm includes more switching cells of the second type than switching cells of the first type. The switching cells of the first type have lower conduction loss than the switching cells of the second type. The converter is arranged so that a larger current flows through the first arm than the second arm.

Abstract: A converter arrangement for an AC system includes a phase leg including a first sub-converter, a second sub-converter, an IPT interface configured for connecting the first and second sub-converters with a phase line A, and at least one DC bus connected to the first and second sub-converters. The first sub-converter is connected in parallel with the second sub-converter between the DC bus and the IPT interface. Each of the first and second sub-converters includes a chain-link converter connected to the IPT interface and including a plurality of converter cells connected in series with each other, and a common DC link multilevel converter connected to the DC bus and in series with the chain-link converter.

Abstract: A method of controlling a multilevel converter, a computer program and a controller for a converter is provided. The method includes determining a transition voltage from a control period to a following control period, analyzing the switching cells of each phase leg, selecting capacitors to provide the transition voltage and synthesize the output voltage for the following control period, and connecting the selected capacitors during the following control period. The analyzing of each switching cell includes analyzing a first switching leg and a second switching leg of the switching cell. The method includes determining whether a change of state of the first switching leg would contribute to the direction of the transition voltage, and determining whether a change of state of the second switching leg would contribute to the direction of the transition voltage, and determining the internal conditions of each of the first and the second switching leg that are determined as contributing to the transition.

Abstract: A multi-level power converter includes switching cells, each comprising switching devices and an energy storage element. The switching cells include switching cells of a first type and switching cells of a second type. The converter includes, for each phase, a first arm of serial connected switching cells and a second arm of serial connected switching cells, which first arm and second arm are connected in parallel. The first arm includes more switching cells of the first type than switching cells of the second type and the second arm includes more switching cells of the second type than switching cells of the first type. The switching cells of the first type have lower conduction loss than the switching cells of the second type. The converter is arranged so that a larger current flows through the first arm than the second arm.

Abstract: An energy storage system (ESS) for an electrical system includes an energy storage, and a converter interface arranged for connecting the energy storage to the electrical system. The converter interface includes a modular multilevel converter in which each phase leg includes a plurality of series connected cells of which at least one is a half-bridge cell and at least one is a full-bridge cell.

Abstract: A control system for an electric vehicle charging station (EVCS) is provided, the control system comprises: a central controller configured to receive an ancillary service order from a power grid and distribute the ancillary service order to one or more local controllers periodically; and the one or more local controllers configured to control a plurality of electric vehicle supply devices based on the distributed ancillary service order in real time. The method controlling the electric vehicle charging station (EVCS) is also provided.

Abstract: A converter arrangement and a method of controlling a three-phase converter arrangement connected to a transmission grid are provided. The converter arrangement includes three phase legs and an energy transfer circuit. The method includes providing a varying respective output phase voltage to the transmission grid by selecting energy storage elements of both the phase legs and the energy transfer circuit and connecting the selected energy storage elements to the transmission grid output. The method further includes selecting energy storage elements for performing a transfer of energy between the energy storage elements during the control period.

Abstract: An industrial robot with a manipulator arm including at least one manipulator element and an electric motor driving the at least one manipulator element. An energy reservoir supplies the electric motor with electricity when a power failure or power loss occurs to move the manipulator element from a working position to a safe parking position. Also a method of parking a manipulator arm of an industrial robot.

Abstract: A coordinated control method for a distribution network with DER and EV and coordinated control system thereof includes acquiring information from at least one DER controller, at least one EV controller and/or at least one load controller; calculating P/Q references and/or circuit breaker control commands for the DER, the EV and the load based on active/reactive power balance, voltage and/or frequency requirement; allocating the references and/or the control commands to the DER, the EV and the load based on their locations and available capacity; and outputting the allocated references and/or control commands to the DER, the EV and the load. The solutions minimize negative impacts from DER and EVs and maintain a controllable voltage and frequency stabilization.

Abstract: A method for finding an operating point of an electric motor which includes the steps of generating a perturbation signal, combining the perturbation signal with a current magnitude related to a drive system of the motor or combining the perturbation signal with a power magnitude related to the motor, yielding a combined signal, and sending, based on the combined signal, a flux adjustment signal to adjust a flux of the motor. An apparatus for finding an operating point of an electric motor comprising is also presented.

Abstract: An industrial robot with a manipulator arm including at least one manipulator element and an electric motor driving the at least one manipulator element. An energy reservoir supplies the electric motor with electricity when a power failure or power loss occurs to move the manipulator element from a working position to a safe parking position. Also a method of parking a manipulator arm of an industrial robot.

Abstract: A method for finding an operating point of an electric motor which includes the steps of generating a perturbation signal, combining the perturbation signal with a current magnitude related to a drive system of the motor or combining the perturbation signal with a power magnitude related to the motor, yielding a combined signal, and sending, based on the combined signal, a flux adjustment signal to adjust a flux of the motor. An apparatus for finding an operating point of an electric motor comprising is also presented.