Patents by Inventor Dragan Maksimovic
Dragan Maksimovic 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: 10348202Abstract: A modular dc-dc boost converter system is provided that can substantially improve efficiency over a wide range of input and output voltages. The system includes three modules: a buck module, a boost module, and a dc transformer module. These modules are interconnected such that the system output voltage is equal to the sum of the output voltages of adc-dc converter module and a dc transformer module. Depending on the operating point, one or more modules may operate in passthrough mode, leading to substantially reduced ac losses. The required capacitor size and the transistor voltage ratings are also substantially reduced, relative to a conventional single dc-dc boost converter operating at the same input and output voltages.Type: GrantFiled: April 3, 2017Date of Patent: July 9, 2019Assignee: The Regents of the University of Colorado, a body corporateInventors: Hua Chen, Robert Warren Erickson, Dragan Maksimovic, Tadakazu Harada
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Patent number: 10327292Abstract: One aspect of the invention provides a DC-to-DC driver for at least one light-emitting diode (LED). The driver includes: a converter configured to drive the at least one light emitting diode (LED). The converter includes: an inverter; a rectifier configured to be coupled to the at least one LED; and a resonant tank coupled between the inverter and the rectifier. The resonant tank includes at least two inductors and at least three capacitors. Another aspect of the invention provides a lamp including: at least one light-emitting diode (LED); and the DC-to-DC converter of any of the embodiments of the invention described herein electrically coupled to the at least one light-emitting diode (LED).Type: GrantFiled: July 5, 2018Date of Patent: June 18, 2019Assignee: The Regents of the University of Colorado, a Body CorporateInventors: Alihossein Sepahvand, Dragan Maksimovic, Khurram Afridi
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Patent number: 10298058Abstract: A capacitive wireless power transfer (WPT) architecture that provides for dynamic (i.e., in motion) and/or stationary power transfer is provided. In various implementations, for example, the capacitive WPT architecture can achieve high power transfer levels at high efficiencies while maintaining fringing field strengths within acceptable safety limits. In one implementation, for example, a multi-module capacitive wireless power transfer system provides a capacitive charging system, such as for, but not limited to, charging electric vehicles (EV). In another implementation, a capacitive wireless power transfer module is provided. The module, for example, comprises a plurality of first coupling plates adapted to be coupled to a power source via an inverter; a plurality of second coupling plates adapted to be coupled to a load and to the plurality of first coupling plates for receiving wireless power and a matching network adapted to provide reactive compensation and gain.Type: GrantFiled: May 4, 2016Date of Patent: May 21, 2019Assignee: THE REGENTS OF THE UNIVERSITY OF COLORADO, A BODY CORPORATEInventors: Khurram K. Afridi, Ashish Kumar, Zoya Popovic, Dragan Maksimovic, Chieh-Kai Chang, Guilherme Goularte Da Silva, Saad Pervaiz
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Patent number: 10298026Abstract: An apparatus for model predictive control (“MPC”) is disclosed. A method and system also perform the functions of the apparatus. The apparatus includes a measurement module that receives battery status information from one or more sensors receiving information from a battery cell, and a Kalman filter module that uses a Kalman filter and the battery status information to provide a state estimate vector. The apparatus includes a battery model module that inputs the state estimate vector and battery status information into a battery model and calculates a battery model output, the battery model representing the battery cell, and an MPC optimization module that inputs one or more battery model outputs and an error signal in a model predictive control algorithm to calculate an optimal response. The optimal response includes a modification of the error signal.Type: GrantFiled: July 29, 2016Date of Patent: May 21, 2019Assignee: Utah State UniversityInventors: Michael Scott Trimboli, Gregory L. Plett, Regan A. Zane, Kandler Smith, Dragan Maksimovic, Michael Evzelman, Daniel Costinett, Richard Dyche Anderson
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Patent number: 10277041Abstract: An apparatus includes a battery state module that determines a battery state of each of a plurality of battery cells forming a battery unit. A battery state includes a health of the battery cell. A battery state of a battery cell differs from a battery state of other battery cells of the battery unit. Each battery cell is connected to a shared bus through a bypass converter that provides power from the battery cell to the shared bus. A charge/discharge modification module determines, based on battery state, an amount to vary a charging characteristic for each battery cell compared to a reference charging characteristic. Each charging characteristic varies as a function of a reference state. A charge/discharge module adjusts charging/discharging of a battery cell of the battery unit based on the charging characteristic of the battery cell.Type: GrantFiled: July 29, 2016Date of Patent: April 30, 2019Assignees: UTAH STATE UNIVERSITY, ALLIANCE FOR SUSTAINABLE ENERGY, LLC, FORD GLOBAL TECHNOLOGIES, LLC, THE REGENTS OF THE UNIVERSITY OF COLORADO, A BODY CORPORATEInventors: Regan A. Zane, Michael Evzelman, Daniel Costinett, Dragan Maksimovic, Richard Dyche Anderson, Kandler Smith, Michael Scott Trimboli, Gregory L. Plett
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Publication number: 20190021147Abstract: One aspect of the invention provides a DC-to-DC driver for at least one light-emitting diode (LED). The driver includes: a converter configured to drive the at least one light emitting diode (LED). The converter includes: an inverter; a rectifier configured to be coupled to the at least one LED; and a resonant tank coupled between the inverter and the rectifier. The resonant tank includes at least two inductors and at least three capacitors. Another aspect of the invention provides a lamp including: at least one light-emitting diode (LED); and the DC-to-DC converter of any of the embodiments of the invention described herein electrically coupled to the at least one light-emitting diode (LED).Type: ApplicationFiled: July 5, 2018Publication date: January 17, 2019Applicant: THE REGENTS OF THE UNIVERSITY OF COLORADO, A BODY CORPORATEInventors: ALIHOSSEIN SEPAHVAND, DRAGAN MAKSIMOVIC, KHURRAM AFRIDI
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Publication number: 20190013800Abstract: One aspect of the invention provides a DC-to-DC driver including: a converter including an output configured to drive a load with an output current; and a feedback controller coupled to the converter. The feedback controller includes: a pulse-width modulator configured to output a first pulse-width modulated signal to the converter; a first switching mechanism coupled to the pulse-width modulator; a compensator having an output coupled to the first switching mechanism, the compensator configured to generate a first duty cycle control signal based on a comparison of the output current and a first reference voltage; and a sampler having an input coupled to the output of the compensator and an output coupled to the switching mechanism, the sampler configured to generate a second duty cycle control signal based on the first duty cycle control signal.Type: ApplicationFiled: July 5, 2018Publication date: January 10, 2019Applicant: The Regents of the University of Colorado, a Body CorporateInventors: ALIHOSSEIN SEPAHVAND, DRAGAN MAKSIMOVIC, KHURRAM AFRIDI
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Publication number: 20180278181Abstract: A control architecture that overcomes limitations of conventional ac-dc converters and enables bidirectional active and reactive power processing is provided. In one implementation, for example, this may be achieved through the use of unrectified sensed ac signals in the generation of the control commands for the converter. This control architecture, in this example implementation, eliminates or at least reduces zero crossing distortions in the ac current of the converter even with relatively low bandwidth controllers. The concept can be applied to different power stage topologies.Type: ApplicationFiled: March 21, 2018Publication date: September 27, 2018Inventors: Khurram K. Afridi, Usama Anwar, Dragan Maksimovic, Robert W. Erickson
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Patent number: 10063066Abstract: For battery control, an apparatus includes a shared bus and a plurality of isolated direct current (DC) to DC bypass converters. Each bypass converter is associated with one battery unit. Inputs of each bypass converter are in parallel electrical communication with the associated battery unit. Outputs of each bypass converter are in parallel electrical communication with the shared bus. Each bypass converter estimates a battery state for each battery unit and controls the battery state to a reference state.Type: GrantFiled: January 7, 2015Date of Patent: August 28, 2018Assignee: Utah State UniversityInventors: Regan A. Zane, Michael Evzelman, Daniel Costinett, Dragan Maksimovic, Richard Dyche Anderson, Kandler Smith, Michael Scott Trimboli, Gregory Loren Plett
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Publication number: 20180166915Abstract: A capacitive wireless power transfer (WPT) architecture that provides for dynamic (i.e., in motion) and/or stationary power transfer is provided. In various implementations, for example, the capacitive WPT architecture can achieve high power transfer levels at high efficiencies while maintaining fringing field strengths within acceptable safety limits. In one implementation, for example, a multi-module capacitive wireless power transfer system provides a capacitive charging system, such as for, but not limited to, charging electric vehicles (EV). In another implementation, a capacitive wireless power transfer module is provided. The module, for example, comprises a plurality of first coupling plates adapted to be coupled to a power source via an inverter; a plurality of second coupling plates adapted to be coupled to a load and to the plurality of first coupling plates for receiving wireless power and a matching network adapted to provide reactive compensation and gain.Type: ApplicationFiled: May 4, 2016Publication date: June 14, 2018Inventors: Khurram K. Afridi, Ashish Kumar, Zoya Popovic, Dragan Maksimovic, Chieh-Kai Chang, Guilherme Goularte Da Silva, Saad Pervaiz
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Publication number: 20180123496Abstract: In some aspects, an electric vehicle power system may comprise two or more electrically connected power modules connected to a system communication bus. Each power module may comprise a rechargeable battery electrically connected to a DC bus, an inverter circuit electrically connected to the DC bus, and at least one of a single-phase rectifier circuit electrically connected to the DC bus or a multi-phase rectifier circuit electrically connected to the DC bus. A local controller configured to send control signals may be connected to the rechargeable battery, the inverter circuit, and the at least one of the single-phase rectifier circuit or the multi-phase rectifier circuit. The single-phase rectifier circuit may be configured to convert a single-phase AC power signal into the DC voltage of the DC bus. The multi-phase rectifier circuit may be configured to convert a multi-phase AC power signal into the DC voltage of the DC bus.Type: ApplicationFiled: November 1, 2016Publication date: May 3, 2018Inventors: Milan Ilic, Dragan Maksimovic, Mika Nuotio
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Publication number: 20180026540Abstract: A modular dc-dc boost converter system is provided that can substantially improve efficiency over a wide range of input and output voltages. The system includes three modules: a buck module, a boost module, and a dc transformer module. These modules are interconnected such that the system output voltage is equal to the sum of the output voltages of adc-dc converter module and a dc transformer module. Depending on the operating point, one or more modules may operate in passthrough mode, leading to substantially reduced ac losses. The required capacitor size and the transistor voltage ratings are also substantially reduced, relative to a conventional single dc-dc boost converter operating at the same input and output voltages.Type: ApplicationFiled: April 3, 2017Publication date: January 25, 2018Inventors: Hua Chen, Robert Warren Erickson, Dragan Maksimovic, Tadakazu Harada
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Publication number: 20170373585Abstract: A systematic procedure for the synthesis of hybrid feedforward control architectures for pulse-width modulated (PWM) switching converters is provided. In this hybrid feedforward control architecture selected converter variables are sensed and utilized in a particular way based on the converter open-loop characteristics to determine the duty-cycle needed to achieve a control objective. Compared to standard feedback control techniques, advantages can include simpler controller implementation, more convenient sensing, and improved static and dynamic regulation. An example systematic procedure for developing hybrid feedforward controllers is illustrated by first considering a previously known example of hybrid feedforward control: hybrid feedforward control of a boost power factor correction (PFC) rectifier operating in discontinuous conduction mode (DCM).Type: ApplicationFiled: June 26, 2017Publication date: December 28, 2017Inventors: Usama Anwar, Khurram K. Afridi, Dragan Maksimovic
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Patent number: 9712066Abstract: An apparatus includes a first auxiliary switch connected to a positive connection of a switching leg of a DC-to-DC converter. The switching leg includes a first main switch and a second main switch connected at a main switch midpoint. A second auxiliary switch is connected between a negative connection of the switching leg and the first auxiliary switch. A connection point between the first and second auxiliary switches is an auxiliary midpoint. An auxiliary inductor connects the auxiliary midpoint and the main switch midpoint. The main switch midpoint is also connected to other converter elements. The first and second main switches include a first capacitance a second capacitance. A switch regulation module regulates the first and second auxiliary switches to control current in the auxiliary inductor to provide or remove charge from the first and second capacitances to induce zero voltage switching for the first and second main switches.Type: GrantFiled: June 2, 2015Date of Patent: July 18, 2017Assignee: UTAH STATE UNIVERSITYInventors: Regan A Zane, Daniel Seltzer, Dragan Maksimovic, Boris Jacobson, Donald Desrosiers
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Patent number: 9614442Abstract: A modular dc-dc boost converter system is provided that can substantially improve efficiency over a wide range of input and output voltages. The system includes three modules: a buck module, a boost module, and a dc transformer module. These modules are interconnected such that the system output voltage is equal to the sum of the output voltages of adc-dc converter module and a dc transformer module. Depending on the operating point, one or more modules may operate in passthrough mode, leading to substantially reduced ac losses. The required capacitor size and the transistor voltage ratings are also substantially reduced, relative to a conventional single dc-dc boost converter operating at the same input and output voltages.Type: GrantFiled: April 16, 2015Date of Patent: April 4, 2017Assignee: The Regents of the University of Colorado, A Body CorporateInventors: Hua Chen, Robert Warren Erickson, Jr., Dragan Maksimovic, Tadakazu Harada
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Patent number: 9595873Abstract: An apparatus for zero voltage switching is disclosed. A system and method also perform the functions of the apparatus. The apparatus includes an MCT region module that defines a minimum current trajectory (“MCT”) for operation between a maximum positive power output to a maximum negative power output of a bidirectional DC-to-DC converter. The converter includes a dual active bridge series resonant converter. The MCT defines a boundary between a zero voltage switching (“ZVS”) region and a hard switching region. The apparatus includes an offset module that defines an offset to the MCT, the offset in the ZVS region, and an MCT control module that adjust switching of switches of the converter to maintain operation of the converter in the ZVS region between the maximum positive power output to a maximum negative power output along a trajectory defined by the MCT and the offset.Type: GrantFiled: June 2, 2015Date of Patent: March 14, 2017Assignee: UTAH STATE UNIVERSITYInventors: Regan A Zane, Daniel Seltzer, Dragan Maksimovic, Boris Jacobson, Donald Desrosiers
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Patent number: 9584029Abstract: An apparatus includes a voltage regulation module that controls output voltage of a bidirectional DC to DC converter to an output voltage reference over an output current range between a positive power reference and a negative power reference. A positive power regulation module controls output power of the converter to the positive power reference over a positive constant power range between the output voltage reference and a positive output current reference. A negative power regulation module controls output power of the converter to the negative power reference over a constant power range between the output voltage reference and a maximum negative power limit, and a constant current module limits output current to a positive output current reference in a range between a minimum output voltage and output power of the converter reaching the positive power reference.Type: GrantFiled: June 2, 2015Date of Patent: February 28, 2017Assignee: UTAH STATE UNIVERSITYInventors: Regan A Zane, Daniel Seltzer, Dragan Maksimovic, Boris Jacobson, Donald Desrosiers
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Publication number: 20160336767Abstract: An apparatus includes a battery state module that determines a battery state of each of a plurality of battery cells forming a battery unit. A battery state includes a health of the battery cell. A battery state of a battery cell differs from a battery state of other battery cells of the battery unit. Each battery cell is connected to a shared bus through a bypass converter that provides power from the battery cell to the shared bus. A charge/discharge modification module determines, based on battery state, an amount to vary a charging characteristic for each battery cell compared to a reference charging characteristic. Each charging characteristic varies as a function of a reference state. A charge/discharge module adjusts charging/discharging of a battery cell of the battery unit based on the charging characteristic of the battery cell.Type: ApplicationFiled: July 29, 2016Publication date: November 17, 2016Inventors: Regan A. Zane, Michael Evzelman, Daniel Costinett, Dragan Maksimovic, Richard Dyche Anderson, Kandler Smith, Michael Scott Trimboli, Gregory L. Plett
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Publication number: 20160336765Abstract: An apparatus for model predictive control (“MPC”) is disclosed. A method and system also perform the functions of the apparatus. The apparatus includes a measurement module that receives battery status information from one or more sensors receiving information from a battery cell, and a Kalman filter module that uses a Kalman filter and the battery status information to provide a state estimate vector. The apparatus includes a battery model module that inputs the state estimate vector and battery status information into a battery model and calculates a battery model output, the battery model representing the battery cell, and an MPC optimization module that inputs one or more battery model outputs and an error signal in a model predictive control algorithm to calculate an optimal response. The optimal response includes a modification of the error signal.Type: ApplicationFiled: July 29, 2016Publication date: November 17, 2016Inventors: Michael Scott Trimboli, Gregory L. Plett, Regan A. Zane, Kandler Smith, Dragan Maksimovic, Michael Evzelman, Daniel Costinett, Richard Dyche Anderson
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Publication number: 20150349649Abstract: An apparatus for zero voltage switching is disclosed. A system and method also perform the functions of the apparatus. The apparatus includes an MCT region module that defines a minimum current trajectory (“MCT”) for operation between a maximum positive power output to a maximum negative power output of a bidirectional DC-to-DC converter. The converter includes a dual active bridge series resonant converter. The MCT defines a boundary between a zero voltage switching (“ZVS”) region and a hard switching region. The apparatus includes an offset module that defines an offset to the MCT, the offset in the ZVS region, and an MCT control module that adjust switching of switches of the converter to maintain operation of the converter in the ZVS region between the maximum positive power output to a maximum negative power output along a trajectory defined by the MCT and the offset.Type: ApplicationFiled: June 2, 2015Publication date: December 3, 2015Inventors: Regan A. Zane, Daniel Seltzer, Dragan Maksimovic, Boris Jacobson, Donald Desrosiers