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).

  • Publication number: 20200388432
    Abstract: Embodiments of the disclosure relate to apparatuses for enhanced thermal management of an inductor assembly using functionally-graded thermal vias for heat flow control in the windings of the inductor. In one embodiment, a PCB for an inductor assembly includes a top surface and a bottom surface. Two or more electrically-conductive layers are embedded within the PCB and stacked vertically between the top surface and the bottom surface. The two or more electrically-conductive layers are electrically connected to form an inductor winding. A plurality of thermal vias thermally connects each of the two or more electrically-conductive layers to a cold plate thermally connected to the bottom surface. A number of thermal vias thermally connecting each electrically-conductive layer to the cold plate is directly proportional to a predetermined rate of heat dissipation from the electrically-conductive layer.
    Type: Application
    Filed: November 22, 2019
    Publication date: December 10, 2020
    Applicants: Toyota Motor Engineering & Manufacturing North America, Inc., University of Colorado Boulder
    Inventors: Ercan DEDE, Yucheng GAO, Vivek SANKARANARAYANAN, Aritra GHOSH, Robert ERICKSON, Dragan MAKSIMOVIC
  • Patent number: 10855203
    Abstract: A cascaded architecture composed of interconnected blocks that are each designed to process constant power and eliminate bulk energy storage are provided. Further, local controls within each block natively achieve both block- and system-level aims, making the system modular and scalable. Further methods of providing power conversion using such interconnected clocks are also provided.
    Type: Grant
    Filed: May 2, 2019
    Date of Patent: December 1, 2020
    Assignees: The Regents of the University of Colorado, a body corporate, Alliance for Sustainable Energy, LLC
    Inventors: Dragan Maksimovic, Prasanta Achanta, Brian B. Johnson, Miguel Rodriguez, Vahan Gevorgian
  • Publication number: 20200067423
    Abstract: A cascaded architecture composed of interconnected blocks that are each designed to process constant power and eliminate bulk energy storage are provided. Further, local controls within each block natively achieve both block- and system-level aims, making the system modular and scalable. Further methods of providing power conversion using such interconnected clocks are also provided.
    Type: Application
    Filed: May 2, 2019
    Publication date: February 27, 2020
    Inventors: Dragan Maksimovic, Prasanta Achanta, Brian B. Johnson, Miguel Rodriguez, Vahan Gevorgian
  • Patent number: 10554164
    Abstract: 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: Grant
    Filed: November 1, 2016
    Date of Patent: February 4, 2020
    Assignee: SUNGROW POWER SUPPLY CO., LTD.
    Inventors: Milan Ilic, Dragan Maksimovic, Mika Nuotio
  • Patent number: 10536068
    Abstract: 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: Grant
    Filed: June 26, 2017
    Date of Patent: January 14, 2020
    Assignee: The Regents of the University of Colorado, a body corporate
    Inventors: Usama Anwar, Khurram K. Afridi, Dragan Maksimovic
  • Patent number: 10461633
    Abstract: 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: Grant
    Filed: July 5, 2018
    Date of Patent: October 29, 2019
    Assignee: The Regents of the University of Colorado, a Body Corporate
    Inventors: Alihossein Sepahvand, Dragan Maksimovic, Khurram Afridi
  • Patent number: 10348202
    Abstract: 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: Grant
    Filed: April 3, 2017
    Date of Patent: July 9, 2019
    Assignee: The Regents of the University of Colorado, a body corporate
    Inventors: Hua Chen, Robert Warren Erickson, Dragan Maksimovic, Tadakazu Harada
  • Patent number: 10327292
    Abstract: 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: Grant
    Filed: July 5, 2018
    Date of Patent: June 18, 2019
    Assignee: The Regents of the University of Colorado, a Body Corporate
    Inventors: Alihossein Sepahvand, Dragan Maksimovic, Khurram Afridi
  • Patent number: 10298058
    Abstract: 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: Grant
    Filed: May 4, 2016
    Date of Patent: May 21, 2019
    Assignee: THE REGENTS OF THE UNIVERSITY OF COLORADO, A BODY CORPORATE
    Inventors: Khurram K. Afridi, Ashish Kumar, Zoya Popovic, Dragan Maksimovic, Chieh-Kai Chang, Guilherme Goularte Da Silva, Saad Pervaiz
  • Patent number: 10298026
    Abstract: 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: Grant
    Filed: July 29, 2016
    Date of Patent: May 21, 2019
    Assignee: Utah State University
    Inventors: Michael Scott Trimboli, Gregory L. Plett, Regan A. Zane, Kandler Smith, Dragan Maksimovic, Michael Evzelman, Daniel Costinett, Richard Dyche Anderson
  • Patent number: 10277041
    Abstract: 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: Grant
    Filed: July 29, 2016
    Date of Patent: April 30, 2019
    Assignees: UTAH STATE UNIVERSITY, ALLIANCE FOR SUSTAINABLE ENERGY, LLC, FORD GLOBAL TECHNOLOGIES, LLC, THE REGENTS OF THE UNIVERSITY OF COLORADO, A BODY CORPORATE
    Inventors: Regan A. Zane, Michael Evzelman, Daniel Costinett, Dragan Maksimovic, Richard Dyche Anderson, Kandler Smith, Michael Scott Trimboli, Gregory L. Plett
  • Publication number: 20190021147
    Abstract: 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: Application
    Filed: July 5, 2018
    Publication date: January 17, 2019
    Applicant: THE REGENTS OF THE UNIVERSITY OF COLORADO, A BODY CORPORATE
    Inventors: ALIHOSSEIN SEPAHVAND, DRAGAN MAKSIMOVIC, KHURRAM AFRIDI
  • Publication number: 20190013800
    Abstract: 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: Application
    Filed: July 5, 2018
    Publication date: January 10, 2019
    Applicant: The Regents of the University of Colorado, a Body Corporate
    Inventors: ALIHOSSEIN SEPAHVAND, DRAGAN MAKSIMOVIC, KHURRAM AFRIDI
  • Publication number: 20180278181
    Abstract: 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: Application
    Filed: March 21, 2018
    Publication date: September 27, 2018
    Inventors: Khurram K. Afridi, Usama Anwar, Dragan Maksimovic, Robert W. Erickson
  • Patent number: 10063066
    Abstract: 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: Grant
    Filed: January 7, 2015
    Date of Patent: August 28, 2018
    Assignee: Utah State University
    Inventors: Regan A. Zane, Michael Evzelman, Daniel Costinett, Dragan Maksimovic, Richard Dyche Anderson, Kandler Smith, Michael Scott Trimboli, Gregory Loren Plett
  • Publication number: 20180166915
    Abstract: 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: Application
    Filed: May 4, 2016
    Publication date: June 14, 2018
    Inventors: Khurram K. Afridi, Ashish Kumar, Zoya Popovic, Dragan Maksimovic, Chieh-Kai Chang, Guilherme Goularte Da Silva, Saad Pervaiz
  • Publication number: 20180123496
    Abstract: 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: Application
    Filed: November 1, 2016
    Publication date: May 3, 2018
    Inventors: Milan Ilic, Dragan Maksimovic, Mika Nuotio
  • Publication number: 20180026540
    Abstract: 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: Application
    Filed: April 3, 2017
    Publication date: January 25, 2018
    Inventors: Hua Chen, Robert Warren Erickson, Dragan Maksimovic, Tadakazu Harada
  • Publication number: 20170373585
    Abstract: 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: Application
    Filed: June 26, 2017
    Publication date: December 28, 2017
    Inventors: Usama Anwar, Khurram K. Afridi, Dragan Maksimovic
  • Patent number: 9712066
    Abstract: 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: Grant
    Filed: June 2, 2015
    Date of Patent: July 18, 2017
    Assignee: UTAH STATE UNIVERSITY
    Inventors: Regan A Zane, Daniel Seltzer, Dragan Maksimovic, Boris Jacobson, Donald Desrosiers