公开(公告)号：US20200099313A1

公开(公告)日：2020-03-26

申请号：US16698517

申请日：2019-11-27

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

Inventor： Zhuyong HUANG ,  Xiaofei ZHANG ,  Chuntao ZHANG

IPC: H02M7/483 ,  H02M7/5387

Abstract: A multi-level circuit, a three-phase multi-level circuit, and a control method are provided. The multi-level circuit includes two groups of bus capacitors (C1 and C2) that are connected in series; a plurality of switching transistor branches that are connected in parallel to the capacitors, where each switching transistor branch includes a first half bridge (Q1 and Q2) and a second half bridge (Q3 and Q4), and a common terminal of the two half bridges is grounded (N); and two negative coupled inductors (L1 and L2), where each input terminal of each negative coupled inductor is connected to a common terminal (A1 and A2) of two switching transistors in the first half bridge in only one of the switching transistor branches. In this circuit, a quantity of groups of bus capacitors is decreased and circuit design complexity is reduced. Further, a dropout voltage of the switching transistors is reduced.

公开(公告)号：US20190312524A1

公开(公告)日：2019-10-10

申请号：US16450360

申请日：2019-06-24

Applicant: Huawei Technologies Co., Ltd.

Inventor： Zhuyong HUANG ,  Xiaofei ZHANG

IPC: H02M7/483 ,  H02M7/5387 ,  H02M7/797 ,  H02M1/08

Abstract: A converter, configured to be connected between a direct current system and an alternating current system for mutual conversion between a direct current and an alternating current, includes a switching network, a filter, and a control unit. The switching network includes a first switching circuit and a second switching circuit. The first switching circuit includes M energy storage elements and M bridge arm circuits, one of the M bridge arm circuits includes one full-controlled component, and remaining M-1 bridge arm circuits each include two full-controlled components that are reversely connected in series. The second switching circuit includes N energy storage elements and N bridge arm circuits, one of the N bridge arm circuits includes one full-controlled component, and remaining N-1 bridge arm circuits each include two full-controlled components that are reversely connected in series.

公开(公告)号：US20190228014A1

公开(公告)日：2019-07-25

申请号：US16370343

申请日：2019-03-29

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

Inventor： Wenjie LIU ,  Jiansheng WEI ,  Xiaofei ZHANG ,  Lei CHEN

IPC: G06F16/2453 ,  G06F16/2455 ,  G06F16/22

Abstract: A control method for performing a multi-table join operation and a corresponding apparatus are disclosed. Fields in a table whose fields participating in a theta join operation and used in the query statement meet a first preset condition are decomposed, to obtain a plurality of first field groups, so that the theta join operation can be implemented in steps in a form of the plurality of field groups. This can reduce a data amount of Cartesian product calculation during one join operation, greatly reduce network transmission overheads, computing overheads, and memory overheads, and improve execution efficiency.