Abstract: A three-phase inverter and a control method therefor are provided. Resonant capacitors are provided between the midpoints of three bridge arms and the positive and negative poles of a DC bus to constitute resonant units with output inductors, so as to establish a resonant network for the implementation of soft switching, without adding a switching transistor. Compared with the soft-switching of the three-phase inverter in the conventional technology, circuit devices are saved, the control process is simplified, and system hardware and software overheads are reduced. By controlling the three-phase inverter to operate in a continuous mode, the switching loss of the switching transistor and the conduction loss of a flyback diode in the switching transistor are reduced, the conversion efficiency is improved, the electromagnetic noise caused by the switching transistor is reduced, and high-quality grid currents are output.

Abstract: A hybrid DC-DC converter includes a converter circuit, a bridge circuit with a bridge path that includes a winding of a transformer, and another bridge circuit with a bridge path that includes another winding of the transformer. Current through the bridge path of the other bridge circuit flows through the converter circuit in one direction and bypasses the converter circuit in the other direction. The converter circuit can operate in buck, boost, or buck-boost mode.

Abstract: In some aspects, a ground detection system may measure a difference from a tie point of the ungrounded electrical system and a ground point to determine if a grounded condition exists. The ground detection system may measure a plurality of signals at a plurality of distributed overload protection devices. The ground detection system may compare the plurality of signals from each of the plurality of distributed overload protection devices to stored threshold values. The ground detection system may determine a location of the grounded condition based at least in part on the comparing the plurality of signals from each of the plurality of distributed overload protection devices to the stored threshold values. In various embodiments, the location can be based on a length and an impedance of electrical circuit wiring. The ground detection system may display the location of the grounded condition on a display. Numerous other aspects are described.

Abstract: Various enhancements to grid-interactive inverters in accordance with embodiments of the invention are disclosed. One embodiment includes input terminals configured to receive a direct current, output terminals configured to provide an alternating output current to the utility grid, a controller, an output current sensor, and a DC-AC inverter stage comprising a plurality of switches controlled by control signals generated by the controller. In addition, the controller is configured to: generate control signals that cause the switches in the DC-AC inverter stage to switch a direct current in a bidirectional manner; measure the alternating output current; perform frequency decomposition of the output current; and generate control signals that cause the switches in the DC-AC inverter stage to switch current in a way that the magnitude of a plurality of unwanted current components is subtracted from the resulting output current.

Abstract: A multi-phase voltage converter has a plurality of integrated circuits (ICs), and a controller. Each IC has a power switch, a monitoring pin and a current sense pin. The power switch is controlled to convert an input voltage to an output voltage. The current sense pin is capable of providing a current sense signal representative of a current flowing through the power switch. The controller is capable of providing a clock signal via the monitoring pin, and provides a plurality of data signals via the current sense pin of the plurality of ICs. Each of the plurality of ICs is assigned an identification code based on the clock signal and one of the plurality of data signals.

Abstract: A power converter includes a switch control circuit for driving a high side switch of the power converter comprising the high side switch and a low side switch connected in series. The switch control circuit may have a first terminal for receiving a low side switch driving signal of the low side switch, a second terminal used as a reference ground terminal of the switch control circuit, and a third terminal used as an output terminal to provide a high side switch driving signal, the switch control circuit can draw power from the low side switch driving signal and may not require internal regulators that should sustain high voltage.

Abstract: A power management integrated circuit (PMIC) chip provides power loss protection to an application device. The PMIC chip has several storage pins that each receives a set of storage capacitors that are charged using power from a power source during normal operation. An application device receives power from the power source during normal operation and receives power from an operational set of storage capacitors during power loss. A failing set of storage capacitors is disconnected from an operational set of storage capacitors and from the PMIC chip. The operational set of storage capacitors remains connected to the PMIC chip to provide power loss protection.

Abstract: A three-phase grid-connected inverter, a control system thereof and a control method therefor. The inverter is a three-phase three-leg grid-connected inverter, and a filter capacitor is connected to a negative electrode of a DC input bus to form a filter loop, so as to filter harmonic wave in the circuit, realizing high-quality grid-connected current at small power, without increasing an inductance value, so that the parallel inverter device in the system operates stably and thus is applicable to photovoltaic microinverters. Moreover, the three-phase three-leg grid-connected inverter operates in a discontinuous conduction mode, that is, in a switching cycle, the inductive current is reduced to 0, so that the switching loss of the three-phase three-leg grid-connected inverter is reduced.

Abstract: A power switch device driver with energy recovery is discussed. The power switch device adopts four switches and one inductor with appropriate control to insure the switching speed and save the power loss.

Abstract: A method of setting a synchronous rectifier on-time value includes determining that a time interval has occurred, receiving a number of triangular current mode (TCM) pulses measured during the time interval, and determining a pulse comparison value equal to a number of switching period pulses during the time interval minus the number of TCM pulses during the time interval. The method also includes increasing the synchronous rectifier on-time if the pulse comparison value is greater than or equal to a threshold and decreasing the synchronous rectifier on-time if the pulse comparison value is less than the threshold.

Abstract: A bipolar plate for a four-fluid fuel cell includes a nonporous sub-plate and a porous sub-plate. The nonporous sub-plate includes a water management side, an opposing reactant side, and an internal coolant passage therebetween. The porous sub-plate includes a reactant side and an opposing water management side. The reactant side includes a first reactant flow field, and the water management side is fluidly connected to the water management side of the nonporous sub-plate. Embodiments of the invention include a method to operate the four-fluid fuel cell in thermal boost mode, and a method to accumulate and retain product water.

Abstract: A mobile pressure washer can include a wheeled chassis, a power plant supported by the wheeled chassis, a fluid pump a fluid pump coupled to and driven by the power plant, a sprayer in fluid communication with the pump, a chemical solution container, and a container holder for supporting the chemical solution container. In some examples, the container holder has a frame operably connected to the wheeled chassis and has a container support mounted to the frame, the container support including a base wall and a sidewall defining a receptacle for receiving and supporting a container in fluid communication with the pump.

Abstract: A vehicle includes a vehicle mass estimator circuit. The vehicle mass estimator circuit is configurable to estimate a mass of vehicle during real-time operation of the vehicle without employing a scale or dedicated mass sensing system. The vehicle mass estimator circuit generates the vehicle mass Mv from: (1) an estimated torque or sensed torque, (2) an estimated motor angular velocity or sensed motor angular velocity, and (3) sensed acceleration or without any sensed acceleration. In one embodiment, the vehicle mass estimator circuit senses motor current during vehicle operation and estimates a mass of the vehicle using the motor current without any dedicated acceleration sensor such as an accelerometer. A motor angular velocity is estimated from the motor current. In another embodiment, the vehicle mass estimator circuit senses motor current during vehicle operation and estimates a mass of the vehicle using the motor current and acceleration information provided by an accelerometer.

Abstract: Electrical power is dynamically managed a power source a load. A control switching system has a plurality of monitor nodes, a control switch having two switching states, and an electrical power storage cell connected to the power source in one of the switching states for storing voltage, and operative for discharging the stored voltage to the electrical load in the other of the switching states. A programmed controller dynamically monitors operating conditions at the monitor nodes during operation of the electrical load and the power source, and switches the control switch between the switching states in response to the monitored operating conditions for supplying a voltage of a desired waveform shape to the electrical load.

Abstract: A method is provided for operating a fuel cell stack with improved performance recovery from sub-saturated conditions, the method comprising setting an alert for the performance recovery of the fuel cell stack, performing at least one oxidant starvation by supplying oxidant at a stoichiometric ratio below 1 to the fuel cell stack in at least one pulse for a preset amount of time and at low current while the fuel cell stack does not generate power. The fuel cell system with an improved performance recovery comprises a shorting circuit which is connected to the fuel cell stack at predetermined times (startup, shutdown or standby mode) and an air compressor powered by a DC-DC converter which supplies a predetermined number of oxidant pulses of a predetermined duration to the fuel cell stack.

Abstract: A power module has a substrate with a bottom side and a component side. Power converters of the power module are implemented using monolithic integrated circuit (IC) switch blocks that are mounted on the component side of the substrate. The power converters include output inductors that are disposed within the substrate. An end of an output inductor is connected to a switch node of a monolithic IC switch block and another end of the output inductor is connected to an output voltage node of the power module.

Abstract: There is provided a light switch system having a housing and a controller secured to the housing. The controller is to control a light source to generate a light output based on a demanded output. The light source is to illuminate at least a portion of an operational volume. The light switch system also has an occupancy sensor communicatively coupled to the controller. The occupancy sensor is to generate an occupancy indicator to indicate whether the operational volume is occupied. Moreover, the light switch system has a functional module communicatively coupled to the controller. In addition, the controller is to divert power from the light source to the functional module by controlling the light source to a the light output to produce an altered light output based on the occupancy indicator.

Abstract: A method of fabricating a vertical fin-based field effect transistor (FET) includes providing a semiconductor substrate having a first surface and a second surface, the semiconductor substrate having a first conductivity type, epitaxially growing a first semiconductor layer on the first surface of the semiconductor substrate, the first semiconductor layer having the first conductivity type and including a drift layer and a graded doping layer on the drift layer, and epitaxially growing a second semiconductor layer having the first conductivity type on the graded doping layer. The method also includes forming a metal compound layer on the second semiconductor layer, forming a patterned hard mask layer on the metal compound layer, and etching the metal compound layer and the second semiconductor layer using the patterned hard mask layer as a mask exposing a surface of the graded doping layer to form a plurality of fins surrounded by a trench.

Abstract: A vertical fin-based field effect transistor (FinFET) includes an array of FinFETs comprising a plurality of rows and columns of active fins with source contacts and one or more rows of first inactive fins disposed on a first set of sides of the array of FinFETs. The vertical FinFET also includes one or more columns of second inactive fins disposed on a second set of sides of the array of FinFETs. The first inactive fins and the second inactive fins are characterized by a reduced electrical conductivity compared to an electrical conductivity of the active fins of the array of FinFETs. The vertical FinFET further includes an active gate region surrounding the FinFETs of the array of FinFETs and an additional gate region surrounding the first inactive fins and the second inactive fins. At least a portion of the additional gate region is a neutralized gate region.

Abstract: A method of forming an alignment contact includes: providing a III-nitride substrate; epitaxially growing a first III-nitride layer on the III-nitride substrate, wherein the first III-nitride layer is characterized by a first conductivity type; forming a plurality of III-nitride fins on the first III-nitride layer, wherein each the plurality of III-nitride fins is separated by one of a plurality of first recess regions, wherein the plurality of III-nitride fins are characterized by the first conductivity type; epitaxially regrowing a III-nitride source contact portion on each of the plurality of III-nitride fins; and forming a source contact structure on the III-nitride source contact portions.