A solid state power transformer is described for converting an input power signal at a first phase or voltage to an output signal of a second voltage or opposite phase by the use of bidirectional solid state switches switched at a high carrier frequency to produce a double-sideband, suppressed-carrier representation of the input power signal, which is then synchronously demodulated using further similar switches to produce the desired output. It is further disclosed that multiple instances of the above with relative phase-staggering of the switching frequency may be operated in parallel and activated or deactivated according to output current demand to provide maximum efficiency over a wide range of current and power levels.

A single-phase AC/DC electric power conversion apparatus includes an indirect matrix converter having an input interface to receive a first alternating current (AC) signal and an output interface to produce a second AC signal, where the first AC signal has a grid frequency. A transformer has a primary winding and an electrically isolated and magnetically coupled secondary winding. A coupling inductor is connected in series between the output interface of the indirect matrix converter and the primary winding. An H-bridge switching arrangement is connected to the secondary winding and produces an output signal having a DC component and at least one AC component. The at least one AC component has a second order harmonic of the grid frequency. An active filter reduces the second order harmonic AC component. A modular conversion apparatus for three-phase power replicates the single-phase apparatus as a module for each phase and omits the active filter.

An exemplary embodiment provides a power conversion system comprising a first battery module, a second battery module, first and second transformers, and first, second, and third current source converter bridges. The transformers can have low voltage sides and high voltage sides. The first bridge can be configured to connect the battery modules and the low voltage sides of the transformers. A mid-point of the serial connection of the battery modules can be connected to a mid-point of the series connection of the transformers. The second bridge can connect to the high voltage side of the first transformer and one or more ports configured to transmit electrical power to and/or receive electrical power from an electrical load and/or source. The third bridge can be configured to connect to the high voltage side of the second transformer and the one and one or more ports.

The present disclosure relates to a system for sourcing and sinking power. The system may have a bi-directional system of electrical components configured for placement in electrical communication with a power source and a load. The bi- directional system may further be configured to source AC and DC power from the power source to the load and sink AC and DC power from the load to the power source. The system may further include a high frequency isolation transformer. In some embodiments, the system may have four input/output channels. The bi-directional system of electrical components may include a line filter configured to reduce harmonic content, a line converter configured for converting between AC power and DC power, a load converter configured for converting between AC power and DC power, and a load filter configured to reduce harmonic content.

A power supply system includes an onboard rectifier that may be disposed onboard an electric vehicle. The onboard rectifier is configured to receive an alternating current conducted from a power generating station via a transmission line at a frequency that is at least a utility power line frequency. The onboard rectifier may change the alternating current into a direct current and to output the direct current to an electric propulsion system of the electric vehicle to power the propulsion system and propel the electric vehicle.

The invention relates to a voltage transformer for converting a primary-side alternating voltage at a first voltage level into a secondary-side alternating voltage at a second voltage level, the voltage transformer having a DC link in which a first direct voltage generated from the primary-side alternating voltage is converted into a second direct voltage by means of a DC-to-DC voltage converter, characterised in that an output circuit for providing a third direct voltage for the connection of at least one load is coupled to the DC link, in particular to the DC-to-DC voltage converter thereof.

A power converter, includes: a first terminal, a second terminal, a third terminal and a fourth terminal; stored-energy-source terminals, to which a stored energy source can be connected; four inverter bridge branches, which are formed from semiconductor switching devices, the inverter bridge branches each having a center tap, each center tap being assigned to one of the terminals, and the inverter bridge branches being interconnected and controllable such that electrical energy can be transferred bidirectionally between the stored-energy-source terminals and the first terminal, the second terminal, the third terminal and/or the fourth terminal; and a control unit, which is designed to control the semiconductor switching devices of the inverter bridge branches.

The disclosed family of electrical power converters consists of two multiphase semiconductor conversion stages to accomplish variable voltage and variable frequency (VVVF) AC-AC power conversion. A middle filter network is positioned between the two conversion stages to absorb high-frequency harmonic currents produced by converter switching and to provide a freewheel path for inductive output currents. Additionally, an input filter network is placed at the input terminals of the first conversion stage to minimize input current distortion, while an output filter network is located at the output terminals of the second conversion stage to suppress high-frequency harmonics in the output currents. Moreover, the disclosed converter family is generalized for N-phase to M-phase power conversion, where N3 and M3.

The disclosed family of electrical power converters consists of two multiphase semiconductor conversion stages to accomplish variable voltage and variable frequency (VVVF) AC-AC power conversion. A middle filter network is positioned between the two conversion stages to absorb high-frequency harmonic currents produced by converter switching and to provide a freewheel path for inductive output currents. Additionally, an input filter network is placed at the input terminals of the first conversion stage to minimize input current distortion, while an output filter network is located at the output terminals of the second conversion stage to suppress high-frequency harmonics in the output currents. Moreover, the disclosed converter family is generalized for N-phase to M-phase power conversion, where N3 and M3.