Amazon Technologies, Inc.

Frederic Pierre Lacaux

Xiaoqi Wang

Andrew Lueneburg

Lizon Maharjan

Marc Ian Feifel

Tausif Husain

Dean Joseph Brestel

Jianqi Shang

Larry W Juang

Michael Szmuk

Marco Antonio De Barros Ceze

Christien Samson Miller

Evan Matthew Francis

Jordan Joseph Proulx Cearns

Marcelino Vazquez Montano

Sensorless propeller damage detection systems and methods may receive and process motor quadrature-axis currents to extract current ripples and fast average current values. In addition, the current ripples and fast average current values may be further processed to generated normalized rms (root-mean-square) values of the current ripples. Further, the calculated values may be compared to one or more threshold values over a time duration to determine whether a propeller is damaged. In this manner, the sensorless propeller damage detection systems and methods may quickly, reliably, and accurately detect propeller damage without any additional sensors or dedicated hardware and with low computational cost, while also minimizing false positive determinations of propeller damage.

Sensorless propeller damage detection systems and methods

Described are systems and methods for monitoring and managing power sharing across multiple loads connected to a shared direct current (DC) bus. Embodiments of the present disclosure may be implemented to monitor and manage power sharing between multiple propulsion mechanisms (e.g., motors) of an aerial vehicle, such as an unmanned aerial vehicle (UAV). One or more shape functions establishing current limits as a function of the DC bus voltage may be determined for each load (e.g., propulsion mechanism/motor) of the multiple loads (e.g., propulsion mechanisms/motors) connected to the DC bus, and the current consumed by each load can be limited based on the DC bus voltage and each shape function.

Power limiting control for shared DC bus loads

Described are systems and methods for providing fault tolerant drivers for electric motors. Embodiments of the present disclosure may provide a single power electronics unit and/or ESC that is configured to drive more than one electric motor. According to exemplary embodiments, each power electronics unit and/or ESC may be connected to more than one electric motor (e.g., three electric motors, etc.) and each power electronics unit and/or ESC may be configured to drive and/or control a single phase of multiple electric motors. This can facilitate two-phase mode operation in the event of a faulty power electronics unit and/or ESC, thereby facilitating continued operation of the affected electric motors. Exemplary embodiments of the present disclosure can also provide alternate modes of operation for the electric motors that are operating in two-phase mode to mitigate thermal stresses that may be experienced by the power electronics and/or the electric motors during two-phase operation.

Fault tolerant motor driver

Described are systems and methods for providing a fault tolerant electrical power system that is configured to continue operating through various fault and/or failure conditions, so as to withstand certain single points of fault and/or failure conditions. Exemplary embodiments of the present disclosure can provide an exemplary electrical power system that includes various components that are electrically coupled to a shared direct current (DC) bus via protection devices that are configured to isolate the various components in the event of certain fault and/or failure conditions. Additionally, the exemplary electrical power system can also include a high-impedance midpoint grounding connection configured to shift the voltages of the shared DC bus in view of certain fault and/or failure conditions, as well as introducing certain separations (e.g., physical and/or electrical) to mitigate the possibility of certain faults and/or failure conditions.

Fault tolerant power architecture

Described are systems and methods for providing a centralized inverter architecture that incorporates multiple inverters co-located in a single integrated power core. Exemplary embodiments of the present disclosure can provide an exemplary power electronics system that includes integrated power core units having multiple inverters co-located in a centralized location. The integrated power cores can enable compute topologies that enable communication between the inverters and coordinated operation of the inverters. The integrated power cores can also be configured as a single line replaceable unit (LRU) to facilitate efficient repair, maintenance, and/or replacement of each integrated power core.

Centralized inverter architecture

Described are systems and methods for monitoring and detecting thermal conditions associated with individual cells of a battery. Embodiments of the present disclosure may monitor, detect, and protect against thermal anomalies that may be experienced at individual cells of a battery, without employing the use of thermal sensors (e.g., a thermocouple, thermistor, etc.). The exemplary systems and methods may be implemented in connection with a battery and/or battery pack having cells arranged in a serial configuration that may be employed in an aerial vehicle, such as an unmanned aerial vehicle (UAV). The described systems and methods detect thermal conditions associated with the individual cells of a battery by modeling each cell as an RC circuit and determining the resistance of each cell based on voltage and current measurements. The determined resistance can approximate and/or be representative of the temperature of the respective cell.

Detection of thermal anomalies in serially connected battery cells

Described are systems and methods for monitoring, detecting, and/or protecting various systems of an aerial vehicle, such as an unmanned aerial vehicle (UAV). Embodiments of the present disclosure can provide a multi-tiered system to provide monitoring, detection, and/or initiation of protection protocols in response to detected faults in connection with the electronics associated with UAV systems, such as the motor drive and/or control systems that may drive the propulsion systems of the UAV.

Tiered electronic protection systems for aerial vehicles

Systems and methods for sensorless motor control may include a back EMF (electromotive force) observer, an adaptive EMF filter, magnitude compensation, hybrid rotor position and speed determination, rotor position and speed blending, and angle compensation. In order to provide accurate and reliable rotor position and speed estimations for a motor over a wide and varied range of speeds, at low speeds, during speed reversals, and/or in the presence of external forces, loads, or torques, the sensorless motor control may utilize a hybrid rotor position and speed determination that leverages both angle-based and magnitude-based methods. Further, the outputs of the two methods may be blended based on a shaping function to generate a final estimated rotor position and speed. Then, the motor may be more accurately and reliably controlled based on the final estimated rotor position and speed.

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Kirkland, WA, United States of America

Frederic Pierre Lacaux