Siemens Aktiengesellschaft

Siemens Corporation

Liviu Mihalache

Mukul Rastogi

Richard H Osman

Edward Alan Cheesman

Edward A Novack

Abdelnassir Abdalla

John B Balicki, Jr

Jr Balicki John B

A method for controlling multiple switching devices (--) of a multilevel converter () includes providing a plurality of carrier signals (C-C) and a reference signal (), the reference signal () having a waveform range divided in a plurality of contiguous bands (B-B), dynamically allocating the plurality of carrier signals (C-C) to the multiple switching devices (--), and generating pulse width modulation signals () to generate switching events of the multiple switching devices (--) based on a comparison of dynamically allocated carrier signals (C-C) with the reference signal (), wherein the plurality of carrier signals (C-C) have a phase shift between the carrier signals (C-C), and wherein the plurality of carrier signals (C-C) are dynamically allocated to the multiple switching devices (--) such that for each switching device (--) the plurality of carrier signals (C-C) are rotated and selected based on a position of the reference signal () with respect to the plurality of bands (B-B).

Pulse width modulation control for a multilevel converter

A printed circuit board (PCB) power cell () for arranging in a multi-cell power supply () includes a housing assembly () with a multiple section housing (), and a PCB assembly () positioned within the housing assembly (), wherein the housing assembly () and the PCB assembly () are configured to provide an integrated voltage isolation of the power cell () which supports an output voltage of the multi-cell power supply (). Furthermore, a multi-cell power supply () including a PCB power cell () with isolation is described.

Printed circuit board power cell with isolation and medium voltage multi-cell power supply

A multilevel converter includes single phase configurations. A single phase configuration has a first half-bridge (HB) module, a second HB module separated by a first capacitor coupled to a DC link, and a neutral point clamped (NPC) module clamped to the first HB module and the second HB module. Further, the single phase configuration has a first individual switching device and a second individual switching device, the first individual switching device operably connected to the first HB module and the NPC module, and the second individual switching device operably connected to the second HB module and the NPC module. The converter further includes a power output assembly comprising multiple phases and providing multiple-phase alternating (AC) power, wherein the single phase configuration supplies power to one of the multiple phases of the power output assembly.

Medium voltage transformerless multilevel converter and method for controlling a medium voltage transformerless multilevel converter

A multilevel converter includes a power supply assembly with a plurality of phases, and a power cell assembly with first power cells and second power cells. The first power cells and second power cells have a same topology and a same current rating, and supply power to the plurality of phases of the power supply assembly. Each phase of the plurality of phases includes a first power cell and a second power cell of the power cell assembly, voltage ratings of the first power cells and the second power cells being different. Furthermore, a method for controlling a multilevel converter and an electric drive system comprising a multilevel converter are disclosed.

Medium voltage hybrid multilevel converter and method for controlling a medium voltage hybrid multilevel converter

A method for controlling a switching device of a multilevel converter includes dynamically selecting a carrier and generating a switching signal to effect a switching event of the switching device based on a comparison of the dynamically selected carrier with a reference signal. The carrier is dynamically selected from a multiple carriers, each corresponding to one of multiple contiguous bands into which range of a waveform of the reference signal is divided. The carriers corresponding to different bands have differing waveform shapes. The dynamically selected carrier corresponds to the band instantaneously occupied by the reference signal. The dynamic selection is executed whereby whenever there is a transition of the reference signal from a first band to a second band, the carriers for the first and second bands are selected dependent on a slope of the reference signal waveform at the transition.

A cascaded multi-level inverter is controlled in fault bypass operation. Rather than relying on approximations or feedback forms, the reference voltages are generated as an analytic solution. The analytic solution and its implementation are not affected by the output frequency of the inverter and it is able to provide maximum possible balanced line-line voltage to a three-phase motor. In addition, the analytic solution provides exact limits for the allowable operation region of the motor power factor in order to prevent overvoltage conditions of the cell inverter.

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Valencia, PA, United States of America

Liviu Mihalache