Patents by Inventor Tin Ho Li
Tin Ho Li has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11843322Abstract: The invention provides a power converter apparatus for converting an alternating current (AC) power input to a direct current (DC) power output. The apparatus comprises a plurality of n single-phase power converting circuits arranged in parallel, where n is equal to or greater than 2, wherein one of said n single-phase power converting circuits comprises a single-stage AC/DC converter module having an operating AC/DC converter; and each of a remaining n?1 of said single-phase power converting circuits comprises a two-stage converter module having an AC/DC converter as an input stage and a DC/DC transformer as an output stage.Type: GrantFiled: October 28, 2021Date of Patent: December 12, 2023Assignee: Hong Kong Applied Science And Technology Research Institute Co., LtdInventors: Sui Pung Cheung, Qing Chun Li, Tin Ho Li
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Publication number: 20230134538Abstract: The invention provides a power converter apparatus for converting an alternating current (AC) power input to a direct current (DC) power output. The apparatus comprises a plurality of n single-phase power converting circuits arranged in parallel, where n is equal to or greater than 2, wherein one of said n single-phase power converting circuits comprises a single-stage AC/DC converter module having an operating AC/DC converter; and each of a remaining n?1 of said single-phase power converting circuits comprises a two-stage converter module having an AC/DC converter as an input stage and a DC/DC transformer as an output stage.Type: ApplicationFiled: October 28, 2021Publication date: May 4, 2023Inventors: Sui Pung Cheung, Qing Chun Li, Tin Ho Li
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Publication number: 20220337166Abstract: A two-stage power converter has a Power-Factor Converter (PFC) and a Dual Active Bridge (DAB) converter connected together by a DC link voltage. The DAB converter outputs a battery voltage with a battery current. A PFC controller divides a reference power constant by the battery voltage to get a battery current reference that is multiplied by a constant and compared to the DC link voltage to adjust Pulse-Width-Modulation (PWM) control signals to the PFC. The reference power constant is compared to the battery current during Constant-Power mode to cause a DAB controller to modulate duty ratio and phase difference between primary and secondary-side PWM control signals to the DAB converter. The DAB converter duty ratio and phase difference are modulated by comparing the battery current to a battery current limit during Constant-Current mode and by comparing the battery voltage to a battery voltage limit during Constant-Voltage mode.Type: ApplicationFiled: June 22, 2022Publication date: October 20, 2022Inventors: Yiu Pang CHAN, Tin Ho LI, Kai Wing Andy YEUNG, Qingchun LI
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Patent number: 11283214Abstract: Described is a power connector device for separating an electrical connection under direct current (DC) voltage or alternating current (AC) voltage between an electrical connector element and an electrical contact element. The power connector device includes the electrical contact element. The electrical contact element has a first conductive part and a second conductive part spaced apart one from the other so as not to be directly electrically conductively connected to one another. The power connector device includes a semiconductor switch for maintaining an electrical connection between the electrical connector element and the electrical contact element during separation of contact between said electrical connector element and said first conductive part to thereby prevent arcing during electrical disengagement of the electrical connector element from the electrical contact element.Type: GrantFiled: February 10, 2021Date of Patent: March 22, 2022Assignee: Hong Kong Applied Science and Technology Research Institute Co., LTDInventors: Chung Yin Lau, Kin Lap Wong, Tin Ho Li
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Patent number: 11277078Abstract: A full-bridge inverter based on a unipolar switching scheme includes a first branch and a second branch in parallel between a first DC node and a second node, the first branch including a first higher switch and a first lower switch in series, and the second branch including a second higher switch and a second lower switch in series. A filter circuit includes a first inductor and a second inductor. One pin of the first inductor is coupled with a first branch conductor, and the first branch conductor is coupled between the first higher switch and the first lower switch, and an opposite pin of the first inductor is electrically coupled with a first output node. One pin of the second inductor is coupled with a second branch conductor, the second branch conductor is coupled between the second higher switch and the second lower switch, and an opposite pin of the second inductor is coupled with a second output node of the full-bridge inverter.Type: GrantFiled: October 26, 2020Date of Patent: March 15, 2022Assignee: ABB Schweiz AGInventors: Enea Bianda, Tin-Ho Li, Juha Huusari, Ngai-Man Ho
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Patent number: 11070045Abstract: An Electrical Protective Device for Low-Voltage DC networks (EPDL) has a controller that on start-up first closes a mechanical relay in a ground line, waits a first delay, then closes a bipolar transistor to allow current to flow through a positive supply line, then turns on a Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) connected in parallel with the bipolar transistor once an output voltage reaches a minimum target. The controller reverses the start-up order to open the MOSFET, bipolar transistor, and finally the relay when an over-voltage, input-power, or integrated-current fault is detected. The output current is integrated over time and compared to a threshold, allowing for capacitor charging or other temporary over-loads. When the output voltage dips below the minimum target, the MOSFET is turned off until the voltage recovers. If the voltage does not recover within a time period, the bipolar transistor and then the relay are turned off.Type: GrantFiled: June 15, 2020Date of Patent: July 20, 2021Assignee: Hong Kong Applied Science and Technology Research Institute Company LimitedInventors: Xin Li, Kin Lap Wong, Tin Ho Li
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Patent number: 11043891Abstract: Described is a controller for an AC to DC or a DC to AC multi-phase power converter of a type having N power converter phases, where N is greater or equal to 2. The controller comprises a control module configured to change or vary a phase shift angle of the input current or output current for each of the N power converter phases such that an average phase shift value for each of said N power converter phases over a control module AC line cycle is about, near or substantially the same value. In an embodiment of an AC/DC or a DC/AC multi-phase power converter of a type having N power converter phases arranged in parallel, an advantage of arranging the average phase shift value for each power converter phase to be substantially equal or about equal over an AC line cycle is that it reduces or eliminates any imbalances in the input currents or output currents of the N power converter phases.Type: GrantFiled: January 23, 2020Date of Patent: June 22, 2021Assignee: Hong Kong Applied Science and Technology Research Institute Company LimitedInventors: Sui Pung Cheung, Qing Chun Li, Xin Li, Tin Ho Li
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Publication number: 20210126554Abstract: A full-bridge inverter based on a unipolar switching scheme includes a first branch and a second branch in parallel between a first DC node and a second node, the first branch including a first higher switch and a first lower switch in series, and the second branch including a second higher switch and a second lower switch in series. A filter circuit includes a first inductor and a second inductor. One pin of the first inductor is coupled with a first branch conductor, and the first branch conductor is coupled between the first higher switch and the first lower switch, and an opposite pin of the first inductor is electrically coupled with a first output node. One pin of the second inductor is coupled with a second branch conductor, the second branch conductor is coupled between the second higher switch and the second lower switch, and an opposite pin of the second inductor is coupled with a second output node of the full-bridge inverter.Type: ApplicationFiled: October 26, 2020Publication date: April 29, 2021Inventors: Enea Bianda, Tin-Ho Li, Juha Huusari, Ngai-Man Ho
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Patent number: 10848066Abstract: Described is a controller for a DC/DC converter of a type having N power stages, where N is a natural number greater or equal to 2. The controller comprises a decision maker module, a proportional-integral-derivative (PID) or proportional-integral (PI) control module and a transient compression control module. The decision maker module determines a first steady state mode of operation and a second transient mode of operation and is configured to switch control between said first steady state mode of operation to said second transient mode of operation when an operating parameter of one of the N power stages exhibits a predetermined operating condition relative to a predetermined operating limit and/or a predetermined, calculated or selected threshold. The PID or PI module regulates the operating parameter during said first steady state mode of operation.Type: GrantFiled: November 15, 2019Date of Patent: November 24, 2020Assignee: Hong Kong Applied Science and Technology Research Institute Company LimitedInventors: Wai To Yan, Kuen Fuat Yuen, Sui Pung Cheung, Tin Ho Li
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Patent number: 9331563Abstract: Exemplary embodiments are directed to an snubber circuit and a power converter having an active circuit. The snubber circuit includes a series connection of a first diode and a first inductor connected between a first interfacing point and a first connection point, a second diode connected between a second connection point and a second interfacing point, a series connection of a third diode and a second inductor between a third interfacing point and the second connection point, a switching device connected between the first connection point and the third interfacing point, and a first capacitor connected between the first connection point and the second connection point. The first, the second, and the third diode are forward-biased along a path between the first interfacing point and the second interfacing point and through the third interfacing point.Type: GrantFiled: April 1, 2014Date of Patent: May 3, 2016Assignee: ABB RESEARCH LTDInventors: Tin-Ho Li, Ngai-Man Ho, Gerardo Escobar, Jonathan Bradshaw
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Patent number: 9093917Abstract: A bridgeless power factor correction circuit as disclosed can include first and second input inductors, a series connection of a first diode and a first controllable semiconductor switch, and a series connection of a second diode and a second controllable semiconductor switch, the series connections being connected in parallel between positive and negative output terminals of the power factor correction circuit. The power factor correction circuit can include a switching circuit adapted to connect a capacitor between the input terminal and the output terminal such that the capacitor is connected between the first input terminal and a potential of the output terminal when input voltage connectable to the input terminals is positive and the capacitor is connected between the second input terminal and a potential of the output terminal when the input voltage connectable to the input terminals is negative.Type: GrantFiled: December 4, 2014Date of Patent: July 28, 2015Assignee: ABB TECHNOLOGY AGInventors: Ngai-Man Ho, Tin-Ho Li
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Publication number: 20150162822Abstract: A bridgeless power factor correction circuit as disclosed can include first and second input inductors, a series connection of a first diode and a first controllable semiconductor switch, and a series connection of a second diode and a second controllable semiconductor switch, the series connections being connected in parallel between positive and negative output terminals of the power factor correction circuit. The power factor correction circuit can include a switching circuit adapted to connect a capacitor between the input terminal and the output terminal such that the capacitor is connected between the first input terminal and a potential of the output terminal when input voltage connectable to the input terminals is positive and the capacitor is connected between the second input terminal and a potential of the output terminal when the input voltage connectable to the input terminals is negative.Type: ApplicationFiled: December 4, 2014Publication date: June 11, 2015Applicant: ABB Technology AGInventors: Ngai-Man Ho, Tin-Ho Li
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Publication number: 20140313627Abstract: Exemplary embodiments are directed to an snubber circuit and a power converter having an active circuit. The snubber circuit includes a series connection of a first diode and a first inductor connected between a first interfacing point and a first connection point, a second diode connected between a second connection point and a second interfacing point, a series connection of a third diode and a second inductor between a third interfacing point and the second connection point, a switching device connected between the first connection point and the third interfacing point, and a first capacitor connected between the first connection point and the second connection point. The first, the second, and the third diode are forward-biased along a path between the first interfacing point and the second interfacing point and through the third interfacing point.Type: ApplicationFiled: April 1, 2014Publication date: October 23, 2014Applicant: ABB Research LtdInventors: Tin-Ho LI, Ngai-Man Ho, Gerardo Escobar, Jonathan Bradshaw
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Patent number: 8107268Abstract: A passive lossless snubber cell for a switched-mode power converter comprises an energy absorbing circuit and an energy resetting circuit coupled to said energy absorbing circuit. The energy absorbing circuit is arranged to release energy stored in a snubber capacitor of the energy absorbing circuit to a storage capacitor of the energy resetting circuit through a resonant pathway of the snubber cell in response to a first switching action of a power converter transistor switch. The energy resetting circuit is arranged to release the energy stored therein to a part of a circuit of the power converter in response to a second switching action of the power converter transistor switch, the second switching action being a successive action to the first switching action. The passive lossless snubber cell has several advantages over existing snubbering techniques.Type: GrantFiled: September 9, 2009Date of Patent: January 31, 2012Assignee: City University of Hong KongInventors: Shu Hung Chung, Tin Ho Li
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Publication number: 20110057639Abstract: A passive lossless snubber cell for a switched-mode power converter comprises an energy absorbing circuit and an energy resetting circuit coupled to said energy absorbing circuit. The energy absorbing circuit is arranged to release energy stored in a snubber capacitor of the energy absorbing circuit to a storage capacitor of the energy resetting circuit through a resonant pathway of the snubber cell in response to a first switching action of a power converter transistor switch. The energy resetting circuit is arranged to release the energy stored therein to a part of a circuit of the power converter in response to a second switching action of the power converter transistor switch, the second switching action being a successive action to the first switching action. The passive lossless snubber cell has several advantages over existing snubbering techniques.Type: ApplicationFiled: September 9, 2009Publication date: March 10, 2011Applicant: CITY UNIVERSITY OF HONG KONGInventors: Shu Hung Chung, Tin Ho Li