University of Michigan

Al-Thaddeus Avestruz

Xiaofan Cui

Xin Zan

Akshay Sarin

Jason Benjamin Siegel

Sung Yul Chu

Chinedum E Okwudire

Neda Masoud

Alireza Ramyar

Shai Revzen

Duncan Abbot

Spencer Haney

A field cancellation device includes a primary coil and a cancellation coil. The primary coil surrounds a primary volume. The cancellation coil is disposed at least in part within the primary volume. Upon simultaneous incidence of an input signal on both coils, the primary coil and the cancellation coil each generate a response to the signal input. The cancellation field associated with the response from the cancellation coil may cancel a portion of the field power in a protected volume, which is the part of the primary volume surrounded by the cancellation coil. The field cancellation device further includes a balancing inductor that controls the balance between the responses generated by the respective coils.

Field cancellation for coil-surrounded circuitry

A power conversion device may perform model-referenced power processing for multiple diverse power nodes. The power conversion device includes interconnects that couple power nodes connection ports to power converters The power converters include a dense tier of power converters sized to correct from varied power flow levels of a defined portion of a population of power nodes to interim power flows in accord with center values for that portion of power nodes. The center values are provided by a model of the power node diversity. The power converters also include a sparse tier. The sparse tier performs power processing to convert from the interim power flows generated by the dense tier to a uniform model-corrected target flow.

Power processing and energy storage

A device for DC-DC conversion includes a plurality of input ports to receive a set of DC voltage inputs, at least one DC voltage input being configured as a differential input, a plurality of input semiconductor switches, each input semiconductor switch being coupled to a respective input port of the plurality of input ports, an inductor coupled to each input semiconductor switch, a pair of output semiconductor switches coupled to the inductor, an output coupled to the inductor via the pair of output semiconductor switches, and a processor configured to generate input switch control signals for the plurality of input semiconductor switches to sequentially and selectively connect each DC voltage input to the inductor to charge the inductor and to generate an output switch control signal for the pair of output semiconductor switches to connect the inductor to the output to discharge the inductor via the output.

Multiple port DC-DC converter

A system includes a body comprising a conduction path, and first and second modules disposed along, and movable relative to, the body, each of the first and second modules including an energy storage device, a terminal, and a power management unit coupling the energy storage device and the terminal. The terminal of each of the first and second modules is capacitively coupled with the conduction path for bidirectional power transfer between the first and second modules via the conduction path.

Wireless power transfer in modular systems

A device for power conversion includes an inductor, a switch having a switching cycle to control current flow through the inductor, a sensor coupled to the inductor to generate a signal representative of the current flow through the inductor, and a controller configured to generate a switch control signal for the switch to implement cycle-by-cycle control of the switching cycle for current-mode control of an output driven by the current flow through the inductor, the controller being coupled to the sensor such that the cycle-by-cycle control is based on the signal representative of the current flow through the inductor. The inductor is configured to exhibit a decrease in inductance with an increase in the current flow through the inductor.

Cycle-by-cycle digital control of DC-DC converters

A power conversion device may perform model-referenced power processing for multiple heterogenous power nodes. The power conversion device includes interconnects that couple power nodes to power converters. The power converters may include a sparse set in which the number of power converters is dependent on the model of the power source heterogeneity. The sparse set performs power processing on the power from the power node to facilitate provision of a target power at a port of the power conversion device.

A system for wireless power transfer includes a plurality of transfer elements, each transfer element of the plurality of transfer elements being configured as a transmitter for the wireless power transfer or a receiver for the wireless power transfer, a plurality of sensors, each sensor of the plurality of sensors being positioned relative to the plurality of transfer elements and configured to generate sensor data indicative of a field implementing the wireless power transfer, and a processor coupled to the plurality of sensors and configured to determine an estimate of a terminal variable level in a respective transfer element of the plurality of transfer elements based on the sensor data, and to determine whether a foreign object is affecting the wireless power transfer based on whether the estimated terminal variable level is different from another assessment of the terminal variable level by more than a threshold.

Foreign object detection in wireless power transfer

A system includes control circuitry configured to control an output signal. The control circuitry and/or various other sources of undesirable signal components may corrupt the control signal used by the control circuitry to correct the output signal. Conditioning circuitry may effect current-domain repair on the control circuitry by providing feedback-based conditioning actuation, including comparator overdrive, to the control circuitry.

Control conditioning

A vehicle-to-vehicle power transfer system for use between a first vehicle and at least a second vehicle. The system includes an electric power system disposed in each of the first and second vehicles configured to provide electrical drive power to a vehicle drive system for propulsion of the associated vehicle and a power transfer system configured to transfer electric power from at least the electric power system of the first vehicle to the electric power system of the second vehicle while the vehicles are in motion or stationary.

Vehicle-to-vehicle power transfer system

A pulse shaping device includes an inductor that is selectively output-coupled to a first port of a capacitor. The inductor is charged to a selected current throughput and then coupled to the first port to generate a first characteristic within the current flowing at a second port of the capacitor. The capacitor is charged until reaching a clamping voltage at the first port. A voltage clamp of the shaping device clamps the first port of the capacitor at the clamping voltage to generate a second characteristic within the current flowing at a second port of the capacitor.

Pulse generator

A device for driving a control terminal of a transistor includes an input terminal, a transformer including an input winding and an output winding, the input winding being coupled to the input terminal, an n-stage buffer circuit configured to generate a drive signal for the control terminal of the transistor, the n-stage buffer circuit being coupled to a first end of the output winding, and a positive feedback path coupled to an output of a stage of the n-stage buffer circuit to provide a DC offset to an input of the n-stage buffer circuit.

Feedback-based transistor driver

A device configured for wireless power transfer includes a digital controller configured to generate a plurality of switch control signals, and a transceiver configured to generate a wireless signal for the wireless power transfer. The transceiver includes a plurality of switches, each switch of the plurality of switches being responsive to a respective switch control signal of the plurality of switch control signals such that the wireless signal has a waveform shaped in accordance with a code sequence for the wireless power transfer. The code sequence is one of a set of predetermined code sequences, each predetermined code sequence being orthogonal to each other predetermined code sequence of the set of predetermined code sequences.

Multiple access wireless power transfer

A receiver for wireless power transfer includes a plurality of passive elements including a coupling element configured to capture an incoming spread spectrum signal, an active switch coupled to the plurality of passive elements, and a controller to generate a control signal for the active switch. The control signal changes a state of the active switch to vary a resonance condition established by the plurality of passive elements.

Switched receiver for wireless power transfer

A system measures wireless power transfer between a transmitter and a receiver. The system includes a sensor circuit including a sensor. The sensor is configured and positioned to generate sensor data indicative of a field. The field is generated in connection with the wireless power transfer. The system further includes a processor coupled to the sensor circuit and configured to determine a power measurement based on the sensor data. The processor is further configured to determine misalignment of the transmitter or the receiver. The processor is also configured to correct an estimate of the power measurement based on the misalignment.

Growing community of inventors

Ann Arbor, MI, United States of America

Al-Thaddeus Avestruz