Abstract: A method for protecting a power system having inverter-interfaced renewable energy sources is provided. The power system includes an inverter and a control system. The control system includes a current controller including a saturation limiter and a proportional and integral (PI) controller, a phase-locked system, and a low-voltage ride-through (LVRT)control unit. The method includes: by using a Park transformation matrix, determining an output voltage of the inverter; determining a modulated voltage of the output voltage; upon detecting a grid fault, obtaining current references by the LVRT control unit; determining a fault current in a first stage of a transient phase of the grid fault; determining a fault current in a second stage of the transient phase; determining a fault current in a third stage of the transient phase; and switching the control system to a fault control mode by tracking the fault currents in the first, second and third stages, to the current references.

Abstract: Embodiments of this application disclose a three-dimensional audio signal processing method and apparatus, to implement sound field classification of a three-dimensional audio signal, to accurately identify the three-dimensional audio signal. An embodiment of this application provides a three-dimensional audio signal processing method, including: performing linear decomposition on a current frame of a three-dimensional audio signal, to obtain a linear decomposition result; obtaining, based on the linear decomposition result, a sound field classification parameter corresponding to the current frame; and determining a sound field classification result of the current frame based on the sound field classification parameter.

Abstract: This application discloses a three-dimensional audio signal coding method and apparatus, and an encoder, and relates to the multimedia field. The method includes: After determining a first quantity of virtual speakers and a first quantity of vote values based on a current frame of a three-dimensional audio signal, a candidate virtual speaker set, and a voting round quantity, the encoder selects a second quantity of representative virtual speakers for the current frame from the first quantity of virtual speakers based on the first quantity of vote values, and further encodes the current frame based on the second quantity of representative virtual speakers for the current frame to obtain a bitstream. This achieves efficient data compression.

Abstract: A three-dimensional audio signal coding method, apparatus, and encoder are described. The method includes, after obtaining a first correlation between a current frame of a three-dimensional audio signal and a representative virtual speaker set for a previous frame, the encoder determines whether the first correlation satisfies a reuse condition, where the first correlation is used to determine whether to reuse the representative virtual speaker set for the previous frame when the current frame is encoded. The method further encodes the current frame based on the representative virtual speaker set for the previous frame when the first correlation satisfies the reuse condition, to obtain a bitstream. A virtual speaker in the representative virtual speaker set for the previous frame is a virtual speaker used for encoding the previous frame of the three-dimensional audio signal.

Abstract: An exemplary two-step method for power system inertia online estimation is described. The first step is to accurately estimate the POI-level aggregated inertia. The second step is to calculate the system-level inertia constant by weighting all the POI-level aggregated inertia and to monitor the inertia spatial distribution. In one example embodiment, the PMU is installed at POI, the frequency spatial difference is considered, and the mechanical power is carefully treated.

Abstract: Systems, apparatuses, and methods for dynamically estimating power losses in a computing system. A system management circuit tracks a state of a computing system and dynamically estimates power losses in the computing system based in part on the state. Based on the estimated power losses, power consumption of the computing system is estimated. In response to detecting reduced power losses in at least a portion of the computing system, the system management circuit is configured to increase a power-performance state of one or more circuits of the computing system while remaining within a power allocation limit of the computing system.

Abstract: A method of adjusting a neuromuscular-signal sensor is provided. The method includes monitoring, based on data from a wearable device that includes a neuromuscular-signal sensor, an impedance at the sensor that impacts the neuromuscular-signal sensor’s ability to sense neuromuscular signals. The neuromuscular-signal sensor is coupled to the wearable device such that it contacts a portion of a user’s skin. In response to detecting a change in the impedance at the neuromuscular-signal sensor that causes the impedance to be outside of a predefined range of impedance values, the method includes causing an adjustment to an operational characteristic (e.g., causing the neuromuscular-signal sensor to move or adjusting an electrical characteristic) associated with the neuromuscular-signal sensor such that the impedance at the neuromuscular-signal sensor is within the predefined range of impedance values after the adjustment to the operational characteristic.

Abstract: Disclosed apparatus may include a membrane, a first electrode supported by the membrane, a second electrode, and optionally a controller configured to control an electrical potential applied between the first electrode and the second electrode. Example apparatus may include one or more flexible membranes that may, at least in part, define an enclosure that is at least partially filled with a dielectric fluid. A flexible membrane may include a functionalized polymer or inorganic dielectric material, such as a fluoropolymer composite including at least one electrically conductive additive and/or at least one toughener. Examples also include associated materials (e.g., polymers), methods of fabrication, methods of apparatus operation, and systems.

Abstract: An actuatable device includes a first ionoelastomer membrane disposed over and locally spaced away from a second ionoelastomer membrane, the first and second ionoelastomer membranes defining a dielectric fluid-containing reservoir therebetween, a primary electrode overlying a portion of the first ionoelastomer membrane, and a secondary electrode overlying a portion of the second ionoelastomer membrane.

Abstract: The disclosed lockable beams for haptics applications may include a rib structure including a plurality of ribs, a linking structure connecting the ribs to each other, a tendon extending along the rib structure, a tensioner coupled to the tendon for applying tension to the tendon, and a locking mechanism configured to, when engaged, impede relative movement between the tendon and the rib structure in a manner that impedes bending of the lockable beam. Various other methods, systems, and devices are also disclosed.

Abstract: Disclosed devices may include a membrane, a first electrode supported by the membrane, a second electrode, a capacitance sensor configured to determine a capacitance measurement between the first electrode and the second electrode, and a controller configured to control an electrical potential applied between the electrode and the second electrode. The controller may be configured to modify the electrical potential based on the capacitance measurement. Example devices may include one or more flexible membranes that may, at least in part, define an enclosure that is at least partially filled with a dielectric fluid. Examples also include associated methods and systems.

Abstract: An electrostatic zipping actuator includes a primary electrode, a secondary electrode overlying the primary electrode, a dielectric layer located between and abutting at least a portion of the primary electrode and the secondary electrode, and a dielectric fluid disposed at least at a junction between the dielectric layer and one of the electrodes, where an average total thickness of the dielectric layer is less than approximately 10 micrometers.

Abstract: Disclosed devices may include a membrane, a first electrode supported by the membrane, a second electrode, a capacitance sensor configured to determine a capacitance measurement between the first electrode and the second electrode, and a controller configured to control an electrical potential applied between the electrode and the second electrode. The controller may be configured to modify the electrical potential based on the capacitance measurement. Example devices may include one or more flexible membranes that may, at least in part, define an enclosure that is at least partially filled with a dielectric fluid. Examples also include associated methods and systems.

Abstract: A high voltage-driven system includes a high voltage optical transformer and a high voltage driven device, where the high voltage optical transformer is located in close proximity to the high voltage driven device. A high voltage connection between the high voltage optical transformer and the high voltage driven device may be shorter than a low voltage connection between the high voltage optical transformer and a low voltage power source used to control the transformer.

Abstract: An electrostatic zipping actuator includes a primary electrode, a secondary electrode overlying the primary electrode, a dielectric layer located between and abutting at least a portion of the primary electrode and the secondary electrode, and a dielectric fluid disposed at least at a junction between the dielectric layer and one of the electrodes, where an average total thickness of the dielectric layer is less than approximately 10 micrometers.

Abstract: A haptic device including an active element and a plurality of passive elements coupled to the active element. Each passive element has a respective response to a wave transmitted by the active element, and is configured to cause a respective haptic effect at a respective location away from the active element. In some embodiments, the respective response includes resonating when energy having a resonant frequency is received. In some embodiments, the wave transmitted by the active element is in the form of a vibration or acoustic energy.

Abstract: An adjustable shoe includes an outsole having a middle portion hingedly attached to a forefoot portion and a heel portion. A segmented driveshaft spans from the forefoot portion of the outsole to the heel portion. Rotation of a front segment of the driveshaft causes the forefoot portion of the outsole to rotate about a hinge axis thereby adjusting a forefoot angle. A first motor is connected to the driveshaft and operable to rotate the driveshaft. A processor is in communication with the first motor and programmed to operate the first motor to provide adjustment to the shoe. A method of adjusting a shoe includes receiving a signal representing a measured force on a portion of an outsole of the shoe. If the measured force exceeds a pre-determined threshold, a motor is activated to change an angle of a forefoot portion of the outsole relative to a middle portion.

Abstract: Disclosed are multilevel buck converters, and controllers and methods for operating such converters. Embodiments improve the voltage gain (Vo/Vin) of multi-level DC-DC converters, such as three-level converters, that is imposed by a duty cycle limitation in conventional approaches. According to certain embodiments, the duty cycle of switches is controlled to so that the converter output voltage is increased.

Abstract: Disclosed are multi-stage multilevel DC-DC step-down converters. Stages may include three or four switches, and switches of each stage are operated at selected duty cycles such that each stage reduces an input voltage by one-half and voltage stress on switches is reduced. In some embodiments only a single output inductor is used in an LC filter, and the inductor may be very small as compared with a conventional Buck converter. Thus, embodiments provide DC-DC step-down converters with high power density and efficiency.