公开(公告)号：US20230344239A1

公开(公告)日：2023-10-26

申请号：US18345556

申请日：2023-06-30

Applicant: Huawei Digital Power Technologies Co., Ltd.

Inventor： Yanzhong ZHANG ,  Hongmiao FANG ,  Bo YU ,  Jinxiang ZHAN ,  Tiansan LIN

IPC: H02J3/38 ,  H02M1/36 ,  H02M7/5387

CPC classification number: H02J3/381 ,  H02M1/36 ,  H02M7/53871 ,  H02J2300/24

Abstract: A first input end of a first inverter is connected to a second end of a direct current positive bus, and a second input end of the first inverter is connected to a second end of a neutral bus. A first input end of a second inverter is connected to the second end of the neutral bus, and a second input end of the second inverter is connected to a second end of a direct current negative bus. A controller is configured to control, in startup and shutdown processes, a voltage to ground of the direct current positive bus, a voltage to ground of the direct current negative bus, and a voltage to ground of the neutral bus each to be less than or equal to a preset voltage threshold, to ensure personal safety and device safety.

公开(公告)号：US20220326294A1

公开(公告)日：2022-10-13

申请号：US17707436

申请日：2022-03-29

Applicant: Huawei Digital Power Technologies Co., Ltd.

Inventor： Zhong WANG ,  Shengjie ZHANG ,  Jianshan LI ,  YU PENG ,  Shijiang YU ,  He ZHOU ,  Bo YU

IPC: G01R31/14 ,  H02J3/38 ,  G01R31/52

Abstract: A photovoltaic energy system and a method for detecting a ground insulation impedance, improve accuracy of detecting a ground insulation impedance after one or more conversion circuits are connected in parallel. The photovoltaic energy system includes one or more conversion circuits and a detection circuit. The detection circuit includes an alternating current signal source and a sampling resistor that are connected in series, a first sampling circuit, and a control circuit. The control circuit is configured to control the alternating current signal source to output harmonic signals of a first frequency and a second frequency. The first sampling circuit is configured to: when the alternating current signal source outputs the harmonic signal of the first frequency, collect a voltage at both terminals of the sampling resistor to obtain a first voltage.