Rockwell Automation Technologies Incorporated

David Dewei Xu

Bin Wu

Navid RezA Zargari

Zhongyuan Cheng

Jingya Dai

Kai Tian

Yuan Xiao

Jiacheng Wang

Ning Zhu

Methods and charging apparatus are presented for charging cell capacitors of a multilevel power conversion system, in which an auxiliary charging source is selectively applied across DC bus terminals while one or more selected multilevel converter cells are alternately switched between a first state to bypass the selected cell or cells and a second state to charge the cell capacitor or capacitors of the selected cell via charging current from the auxiliary charging source.

Modular multilevel converter and charging circuit therefor

Multilevel converters and space vector modulation operating methods are presented in which fewer than all possible switching states are employed for space vector modulation of rectifier and inverter circuits to promote common mode voltage contribution cancellation or reduction therebetween and by using subsets of possible space vector modulation switching states associated with minimal positive or negative common mode voltages and in some cases using virtual vectors which have zero common mode voltages to eliminate the 3rd order harmonic components in common mode voltage as well as to reduce common mode voltage affects associated with multilevel inverter stages.

Multilevel converter systems and methods with reduced common mode voltage

A system comprising low cost topology for power converter systems is provided. The system takes advantage of the voltage-boost characteristic of a current source inverter (CSI) and utilizes a PWM CSI as a grid-side converter for power generation systems. Moreover, the generator-side converter employs low-cost devices, such as, but not limited to diode bridge, thyristor bridge, and/or a combination of diodes and thyristors, and accordingly simplifies generator-side converter and control. Further, the system provides a wider range of operation than traditional voltage source converter based topologies that utilize a voltage source inverter (VSI) as the grid-side convertor along with a diode rectifier as the generator-side converter.

Low cost current source converters for power generation application

Power conversion systems and integrated multi-phase chokes providing high common mode to differential mode choke inductance ratios with circular and triangular shapes for concurrent differential filtering and common-mode voltage blocking in motor drives and other power conversion applications.

Multi-phase power converters and integrated choke therfor

Current source converter (CSC) based wind energy power conversion systems (WECS) and methods are presented in which a unified DC link current control scheme is employed to facilitate grid fault ride-through conditions, with a multiple-mode converter control system that combines the power flow control capabilities of the generator-side and grid-side converters, in which transitions between normal operation and fault condition are achieved automatically by monitoring the grid voltage without the need for, or with partial additional ride-through components.

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Pickering, Canada

David Dewei Xu