公开(公告)号：US10965169B2

公开(公告)日：2021-03-30

申请号：US16011883

申请日：2018-06-19

Applicant: WITS Co., Ltd.

Inventor： Seung Won Park ,  Eun Young Shin ,  Byoung Woo Ryu ,  Hyo Young Kim ,  Yun Ki Hong ,  Young Seung Roh

IPC: H01F27/42 ,  H01F37/00 ,  H01F38/00 ,  H02J50/40 ,  H02J50/12 ,  H02J5/00 ,  H02J50/70 ,  H02J7/02

Abstract: A wireless power transmitter includes: a power supply configured to supply a driving power; a first power transmitter including first bridge switching elements forming a first bridge circuit, and configured to receive the driving power to transmit a first power, wherein a magnitude of a first input voltage applied to the first bridge circuit is determined by a duty of at least one of the first bridge switching elements; a second power transmitter including second bridge switching elements forming a second bridge circuit, and configured to receive the driving power to transmit a second power, wherein a magnitude of a second input voltage applied to the second bridge circuit is determined by a duty of at least one of the second bridge switching elements; and a controller configured to output first and second power transmitting control signals respectively controlling the first bridge switching elements and the second bridge switching elements.

公开(公告)号：US10749381B2

公开(公告)日：2020-08-18

申请号：US15801871

申请日：2017-11-02

Applicant: WITS Co., Ltd.

Inventor： Dong Woo Han ,  Byoung Woo Ryu ,  Hyo Young Kim ,  Se Joo Kim ,  Young Seung Roh

IPC: H02J50/12 ,  H02M7/48 ,  H02M1/00 ,  H02J7/02

Abstract: A wireless power transmission device including a resonant circuit magnetically coupled to a wireless power reception device and being configured to wirelessly transmit power, an alternating current (AC) generator including switches and being configured to receive a direct current (DC) voltage and to generate an AC current, according to a switching operation of the switches, to be supplied to the resonant circuit, and a variable capacitor connected to an output terminal of the AC generator and having a first capacitance, when a load state of the wireless power reception device is provided as a full load state and a second capacitance lower than the first capacitance, when the load state is provided as a light load state.

公开(公告)号：US10483803B2

公开(公告)日：2019-11-19

申请号：US15471287

申请日：2017-03-28

Applicant: WITS Co., Ltd.

Inventor： Sang Ho Cho ,  Seung Won Park ,  Eun Young Shin ,  Hyo Young Kim ,  Young Seung Roh

IPC: H02J50/12 ,  H02J7/02 ,  H02M7/5387 ,  H02M7/48

Abstract: A wireless power transmitter includes: a converter including switching elements forming a bridge circuit, wherein the converter is configured to output an alternating current (AC) voltage including a frequency determined according to an operating frequency of at least one switching element among the switching elements; a resonator including an inductor and a capacitor, and configured to receive the AC voltage to wirelessly transmit power; and a controller configured to output control signals controlling the switching elements so that the converter performs a first mode operation in which an operating duty cycle is fixed and the operating frequency is varied, and an operation of the converter is switched from the first mode operation to a second mode operation in which the operating frequency is fixed and the operating duty cycle is varied, in response to the operating frequency reaching a first reference frequency.

公开(公告)号：US10418857B2

公开(公告)日：2019-09-17

申请号：US15790815

申请日：2017-10-23

Applicant: WITS Co., Ltd.

Inventor： Hyo Young Kim ,  Seung Won Park ,  Eun Young Shin ,  Byoung Woo Ryu ,  Dong Woo Han ,  Ye Ji Park ,  Young Seung Roh

IPC: H02J50/12 ,  H02M7/539 ,  H02M1/14 ,  H02M1/36 ,  H02M3/155 ,  H02M7/48 ,  H02J50/80 ,  H02J7/02 ,  H02M1/00

Abstract: A wireless power transmitter includes: a converter including switching elements forming a bridge circuit and configured to output an alternating current (AC) voltage in response to control signals; a resonator including a resonant capacitor and a resonant coil, and configured to receive the AC voltage to transmit power wirelessly; and a controller configured to set a dead time at which a magnitude of the AC voltage is substantially zero in response to a signal received from a wireless power receiver.