A transfer switch configured to detect a ground current is configured to selectively connect a first power source or a second power source to a load. Each of the power sources includes at least one “hot” lead and one neutral lead, and the transfer switch is configured to switch both the “hot” and the neutral leads. If the neutral switching portion of the transfer switch fails, current may be supplied to the load via the “hot” lead of one of the power sources and return from the load via a ground conductor and the neutral lead of the other power source. The transfer switch includes a current sensor, detecting current on the ground conductor, in order to detect such a condition. The signal from the current sensor is provided to a control circuit, which, in turn, activates an indicator if the current on the ground conductor exceeds a predefined level.

A transmit pad inspection device includes a magnetic coupling device, which includes an inductive circuit that is configured to magnetically couple to a primary circuit of a charging device in a transmit pad through an alternating current (AC) magnetic field. The inductive circuit functions as a secondary circuit for a set of magnetically coupled coils. The magnetic coupling device further includes a rectification circuit, and includes a controllable load bank or is configured to be connected to an external controllable load back. The transmit pad inspection device is configured to determine the efficiency of power transfer under various coupling conditions. In addition, the transmit pad inspection device can be configured to measure residual magnetic field and the frequency of the input current, and to determine whether the charging device has been installed properly.

Embodiments include systems and methods of powering a mobile device using a sink device. The method may include detecting a coupling of the mobile device to the sink device and transmitting an acknowledgement in response to a query, the acknowledgement confirming that the sink device has charging capability. Power may be selectively provided in response to the power request. According to some embodiments, the method includes transmitting a query by a communications transmitter to determine if a sink device has charging capability, and deactivating a driver for a power line and transmitting a power request using the communications transmitter in response to receiving an acknowledgement signal from the sink device. The method may further include selectively providing power received from the sink device to a charging circuit of the mobile device. The mobile device may include an HDMI transmitter for communicating through a transmission line to an HDMI sink device.

A method of providing operating electrical power from a stationary power source to a mobile conveyor utilized in material handling at a mine site as the conveyor moves over a predetermined path at the site without having to move long lengths of cable as the conveyor moves away from the power source. The method utilizes a cable reel that features a power receptacle into which a cable connector can be easily plugged and unplugged.

A power control apparatus is mounted on an electrically driven vehicle which includes an electrical storage device configured by connecting a plurality of batteries in parallel, a voltage detection unit which detects a voltage of each battery, and a load, and the power control apparatus includes, a voltage deviation calculation unit which is connected to the electrical storage device, and calculates voltage deviation between the plurality of batteries based on the voltage detected by each voltage detection unit at the time of driving the load which is driven by power supply from the electrical storage device, a comparator which compares the voltage deviation calculated by the voltage deviation calculation unit and a first predetermined threshold, and a cutoff detection unit which detects a presence or absence of the battery, which comes into a cutoff state in the electrical storage device, when the voltage deviation is equal to or more than the first threshold in a comparison result by the comparator.

The system includes a first and a second power supply terminal configured to have at least one of a battery and a generator connected thereto, a first external terminal coupled to the first power supply terminal, and a second external terminal coupled to the second power supply terminal, and a protection unit connected between the first external terminal and the first power supply terminal. The protection unit includes a semiconductor switching unit having a load path and a control terminal, the load path connected between the first external terminal and the first power supply terminal, and a control circuit coupled to the control terminal of the semiconductor switching unit and configured to switch the switching unit on and off dependent on at least one electrical parameter in the on-board power supply system.

A phase balancing system includes a load forecasting module, a phase unbalance identification module and a demand response module. The load forecasting module determines a load forecast for the distribution system for the period of interest and the phase unbalance identification module determines voltage unbalance on the distribution system for the period of interest. The demand response module estimates an available demand response on the distribution system for the period of interest and allocates an optimized demand response from the available demand response to minimize the voltage unbalance on the distribution system for the period of interest.

Aspects of the invention are directed to apparatus and methods for controlling power distribution to a plurality of devices including a primary device and at least one secondary device, the primary device having at least a first mode of operation and a second mode of operation, with the second mode of operation being a lower power mode of operation than the first mode of operation.

A power distribution system for distributing electric power generated by a wind farm between an AC power transmission link and a DC power transmission link is provided. Both power transmission links connect the wind farm to a substation of a power grid. The power distribution system includes a central wind farm controller and a distribution device. In response to a control signal from the central wind farm controller, the distribution device distributes the generated electrical power between the two power transmission links. It is further described a power transmission system with the above described power distribution system and a method for distributing electric power between an AC power transmission link and a DC power transmission link.

Systems and methods to operate a power supply. A power supply has an inductor and a capacitor coupled in a substantially series connection. The power supply has a first selectably conductive path that selectably couples a first power pack to the series reactive circuit and a second selectably conductive path that selectably couples the series reactive circuit to a substantially series combination of the first power pack and a second power pack. When the first power pack output voltage is above the threshold, the first selectably conductive path couples electrical current between the first power pack to the series reactive circuit. Otherwise, the second selectably conductive path couples electrical current between the series combination and the series reactive circuit. The controller further transfers charge from the second power pack to the first power pack.

A back-up feed system includes a feed input, a feed output, and a feed switching device. The feed input is coupled with an electrical power source. The feed output can couple with power lines in a power distribution unit at a location downstream from circuit protection devices the power distribution unit. The feed switching device can supply back-up electrical power from the power source to electrical systems in the event of a fault condition in the power distribution unit.

A boost converter with a multiple input and with improved efficiency has two or more inputs. A DC voltage source can be connected to each input. A common output carries a DC voltage whose value is greater than or equal to that of the input voltages. The common output is in each case connected to each of the plurality of inputs via a positive lead branch and a negative lead branch. At least one inductor is arranged in the positive lead branch and/or the negative lead branch from each input, and at least one rectification element is arranged in the positive lead branch and/or the negative lead branch from each input. Furthermore, the inputs can be connected in series by means of two or more switching elements via the inductors, wherein at least two of the inductors can in each case be connected in parallel.

The power of DC electrical sources is combined onto a DC buss, such that each source behaves independently from any other source attached to the buss. In one embodiment, a converter module is attached to each of a plurality of solar photovoltaic panels and its output is attached in a parallel manner to a common buss that forms the input to a DC AC inverter. The converter module includes a Maximum Power Point Tracking component that matches the output impedance of the panels to the input impedance of the converter module. The converter also includes a communication component that provides parametric data and identification to a central inverter. Data generated by each converter module is transmitted over the power line or by wireless means and is collected at the inverter and forwarded to a data collection and reporting system.

A circuit and method for wirelessly coupling an electrical energy between an electrical energy source and at least one load is provided. The circuit comprises a primary unit and at least one secondary unit. The primary unit includes an input node for receiving an input voltage produced by the energy source; a transmitter circuit including a transmitter coil configured to generate an electromagnetic field; and a regulator. The regulator is configured to sense a current consumption of the primary unit, determine a gradient of the current consumption with respect to different input voltages, and determine an optimal input voltage based on the gradient. The at least one secondary unit comprises a receiver circuit and a load. The receiver unit includes a coil that wirelessly and inductively couples with the electromagnetic field of the primary unit to receive power therefrom. The receiver unit further includes a regulator circuit configured to provide a constant power to an output node.

Embodiments of the present invention provide an electronic switch for commodity use. Specifically, embodiments of this invention provide a high capacity intelligent electronic switch for commodity use. A flexible film substrate is used along with a field-effect transistor (FET) to produce a commodity switch. Multiple printed flexible electronics PFE substrates are stacked to and integrated into an electronic switch system. Various methods are used to measure power consumption within the switch. The modular cell design allows for horizontal and vertical scaling.

A power control device for an electronic device includes a power switching unit for switching to output a dc power source to a load of the electronic device according to a power switching signal, a switching detection unit for responding a power switching status to generate a switching detection signal, a status latch module for generating the power switching signal according to the switching detection signal, a first status signal and a second status signal, and a logic unit for generating the first status signal and the second status signal for the status latch module according to the power switching signal, such that the status latch module latches the first status signal and the second status signal.

A system for distributing electric power to an electrical grid. The system includes a DC/AC inverter arranged to convert a DC voltage output from an electric power generator to an AC voltage, a transformer arranged to receive the AC voltage, transform the AC voltage and deliver the transformed AC voltage to the grid, and a connector arranged to selectively connect and disconnect the transformer from the grid. The DC/AC inverter is arranged to control primary winding magnetizing current delivered to the transformer. Further, the connector is arranged to selectively connect and disconnect the grid to and from the transformer on the basis of the controlled magnetizing current.

An inverter circuit contains a first and second DC sources for providing a DC voltage, a common step-up converter for boosting the DC voltage, an intermediate circuit capacitor connected between the outputs of the common step-up converter, and an inverter for converting the DC voltage provided by the capacitor into an AC voltage. The common step-up converter contains a series circuit having a first inductance and a first rectifier element and is connected between an output of the first DC source and one side of the intermediate circuit capacitor as well as a series circuit which includes a second inductance and a second rectifier element and is connected between an output of the second DC source and another side of the intermediate circuit capacitor. The common step-up converter further contains a common switching element which is connected between the first and second DC sources.

A vehicle is supplied by a first electrical energy storage unit on board the vehicle, and a ground electrical network providing an energy supply by application of a supply voltage through electrical distribution. The first energy storage unit is controllable under a generator regime or a receiver regime. The supply voltage is adjusted, in the generator regime, by applying an algebraically additive supply voltage originating from the first electrical storage unit to the distribution, to maintain a supply voltage above a minimum threshold. In the receiver regime, if a surplus of supply voltage originating at least partially from a second storage unit in the generator regime is detected above the minimum threshold, this surplus is channeled energetically to the first energy storage unit of the vehicle if it is required for operating the vehicle and enables maintaining the supply voltage below a maximum threshold and above the minimum threshold.

A power generation and control system is easily installed in a consumer household, a business, or an end-user establishment for generating power and preventing power from flowing to a power grid from a consumer circuit during a power outage. A communications transceiver is adapted to transmit a permission signal for allowing power generation only after the control system has been installed. The control system can be adapted to replace an existing circuit breaker in a household circuit breaker box and prevents power from traveling from consumer power generators to the grid during a power outage. In the same manner that end-users can add appliances to existing circuits, end-users can easily add additional power generation devices without hiring a professional electrician and without worrying about causing harm to utility workman during power outages.

A system and method for combining power from DC power sources. Each power source is coupled to a converter. Each converter converts input power to output power by monitoring and maintaining the input power at a maximum power point. Substantially all input power is converted to the output power, and the controlling is performed by allowing output voltage of the converter to vary. The converters are coupled in series. An inverter is connected in parallel with the series connection of the converters and inverts a DC input to the inverter from the converters into an AC output. The inverter maintains the voltage at the inverter input at a desirable voltage by varying the amount of the series current drawn from the converters. The series current and the output power of the converters, determine the output voltage at each converter.

The switch device includes a control switch that turns on/off an electrical connection between an apparatus and the power supply, a condition judging circuit that judges conditions of driving the control switch, an electric wave reception circuit that receives an electric wave, and a power supply circuit that generates power from the electric wave received by the electric wave reception circuit. An electric wave transmission device that transmits an electric wave for making the switch device operate is arranged in a space, whereby the electric wave can be received by the electric wave reception device in the specific space. The switch device controls the control switch to be turned off/on when the electric wave is received. Alternatively, when the electric wave is not received, the switch device turns on/off the control switch.

A hinge assembly having a hollow and partially annular clutch is arranged to pivotally couple a portable computer base portion to a portable computer lid portion. The hinge assembly includes at least an elongated, hollow and partially open cylindrical portion that includes a partially annular outer region and a central bore region, the central bore region suitably arranged to provide support for electrical conductors between the base and lid portions. The hinge assembly also includes a plurality of fastening components that couple the hollow clutch to the base portion and the lid portion of the portable computer, with at least one of the fastening regions being integrally formed with the hollow and partially open cylindrical portion such that space, size and part count are minimized.

A monitor fixing mechanism for fixing a monitor is disclosed. The monitor fixing structure includes a pivot plate and a support member. The pivot plate is detachably connected to the support plate so as to pivot the monitor relative to a stand. The support member includes a plate, at least one lateral guiding structure disposed on the plate for laterally constraining movement of the pivot plate as the pivot plate is sliding into the plate in a first direction, and at least one stopping structure disposed on the plate for stopping an end of the pivot plate as the pivot plate has slid into the plate in the first direction completely. The monitor fixing mechanism further includes a fastening module for fastening the pivot plate on the support member as the pivot plate has slid into the plate in the first direction completely.

A mounting apparatus for a solid state disk includes a bracket and a latching module. The bracket includes a connecting pole and a supporting member mounted to the connecting pole. The latching module is installed to the supporting member, and comprises a latching member. The supporting member includes a position pole mounted to the connecting pole and a supporting bar perpendicularly extending out from the position pole. The position pole defines a latching slot facing the supporting bar for positioning an end of the solid state disk. The supporting bar defines a guiding slot facing the latching slot for receiving a side of the solid state disk. The latching member is to latch onto the solid state disk.

A mobile terminal has a waterproof sheet interposed between a first body portion and a second body portion. The waterproof sheet is formed with a curved shaped or step-like cross-section in consideration of characteristic of internal component or a battery arranged on the first body portion of the mobile terminal, the curved shaped or step-like cross-section is configured to encase, in part or in whole, the internal component or the battery.

An electronic component assembly includes a housing that provides a cavity filled with a cooling fluid that has a liquid phase and a vapor phase. An electronic element is arranged in the cavity and is configured to generate heat. A wicking material is arranged in the cavity between the housing and the electronic device. The cavity provides a gap adjacent to the wicking material. The wicking material is configured to absorb the liquid phase, and the vapor phase is provided in the gap.

An electric power conversion apparatus includes a channel case in which a cooling water channel is formed; a double side cooling semiconductor module that has an upper and lower arms series circuit of an inverter circuit; a capacitor module; a direct current connector; and an alternate current connector. The semiconductor module includes first and second heat dissipation metals whose outer surfaces are heat dissipation surfaces, the upper and lower arms series circuit is disposed tightly between the first heat dissipation metal and the second heat dissipation metal, and the semiconductor module further includes a direct current positive terminal, a direct current negative terminal, and an alternate current terminal which protrude to outside. The channel case is provided with the cooling water channel which extends from a cooling water inlet to a cooling water outlet, and a first opening which opens into the cooling water channel.

A waterproof controller used for electric power steering includes a shell, a chamber, at least one sealing block, a circuit board, at least one cable, and at least one board mounting accessory. The chamber is formed in the shell. The sealing block is disposed on the shell, and includes at least one hole. The circuit board is accommodated in the chamber. The cable includes a first terminal and a second terminal opposite to the first terminal. The first terminal passes through the hole of the sealing block. The board mounting accessory covers the second terminal, in which the board mounting accessory and the second terminal insert into the circuit board together.

A power semiconductor has power terminals arranged in a row at one side of the housing, with control terminals arranged in a row at the other side of the housing. The spacing between adjacent power terminals is greater than the spacing between adjacent control terminals.

An electronic device may be provided with a printed circuit board having padded through-holes. The padded through-holes may be formed from openings in a printed circuit board substrate and elastomeric members in the openings. The elastomeric members may be conductive elastomeric members such as electrically or thermally conductive elastomeric members. The printed circuit board may be secured within a housing for the electronic device using engagement members that extend through padded through-holes. The engagement members may engage with the housing or with additional engagement members that are attached to the housing. The electronic device may include a cowling structure formed over electronic components on a surface of the printed circuit board. The cowling structure may be secured to the printed circuit board using attachment members that engage with the engagement members in the padded through-holes.

A converter power unit comprises: a heat sink; n power switch modules on the heat sink; a first group of laminated bus bars comprising a first and a second bus bar; a capacitor group comprising m capacitor; a second group of laminated bus bars comprising a third and a fourth bus bar, the first bus bar is connected with the third bus bar, the second bus bar is connected with the fourth bus bar; providing that vertical projection areas projected by an area occupied by the n power switch modules and projected by the capacitor group on a first plane perpendicular to an axial direction of the capacitor group are defined as a first and a second projection areas respectively, the first and the second projection area have an overlapped area. The present application can reduce the stray inductances in the commutating loop of the converter.

A printed circuit board includes a motherboard and a daughterboard. The motherboard includes at least one first signal pad and defines at least one via under the at least one first signal pad. The daughterboard includes at least one second signal pad and defines at least one via under the at least one second signal pad. The at least one first signal pad and the at least one second signal pad are sucked into the respective vias on the motherboard and the daughterboard according to siphon principle to allow each of the first signal pads and the second signal pads to form uneven top surfaces, the uneven top surfaces of the at least one first signal pads and the at least one second signal pads are connected to each other for electronically connecting the daughterboard to the motherboard.

A lightweight radio/CD player for vehicular application is virtually “fastenerless” and includes a case and frontal interface formed of polymer based material that is molded to provide details to accept audio devices such as playback mechanisms (if desired) and radio receivers, as well as the circuit boards required for electrical control and display. The case and frontal interface are of composite structure, including an insert molded electrically conductive wire mesh screen that has been pre-formed to contour with the molding operation. The wire mesh provides EMC, RFI, BCI and ESD shielding and grounding of the circuit boards via exposed wire mesh pads and adjacent ground clips. The major components and subassemblies self-interconnect by integral guide and connection features effecting “slide lock” and “snap lock” self-interconnection. The major components and subassemblies self-ground by establishing an interference fit with exposed, resilient, embossed portions of wire mesh.

A power inverter includes a power semiconductor module that includes a power semiconductor device, a control circuit board that outputs a control signal used for controlling the power semiconductor device, a driver circuit board that outputs a driving signal used for driving the power semiconductor device, a conductive metal base plate arranged in a space between the driver circuit board and the control circuit board in which a fine and long opening portion is formed, wiring that connects the driver circuit board and the control circuit board through the opening portion and delivers the control signal to the driver circuit board, and an AC busbar that is arranged on a side opposite to the metal base plate through the driver circuit board and delivers an AC current output from the power semiconductor module to a drive motor. At least a portion of the AC busbar that faces the opening portion extends in a direction directly running in a longitudinal direction of the fine and long opening portion.

In one embodiment, the system comprises: (a) a chassis; (b) one or more cards mounted in the chassis, each card having a plurality of switch ports, the plurality of switch ports being aligned in one or more columns; (c) an aggregator mounted adjacent the chassis, the aggregator having a plurality of bays, each bay being aligned with a card in the chassis, at least one of the bays having a faceplate comprising at least first and second aggregator ports aligned in a column; (d) at least first and second hydras, wherein each hydra comprises at least (i) a first connector; (ii) a plurality of second connectors; (iii) a plurality of conductors, each conductor connecting the first connector to one of the second connectors, the plurality of conductors being bundled together to form a trunk portion from the first connector to a breakout point, the plurality of conductors being separated into breakout portions from the breakout point to the second connectors; (iv) wherein the trunk portion of the first cable is longer than that of the second cable; and (e) wherein the first connector of the first hydra is connected to the first aggregator port and the second connectors of the first hydra are connected to a first set of switch ports, and the first connector of the second hydra is connected to the second aggregator port and the second connectors of the second hydra are connected to a second set of switch ports, wherein the first set of switch ports are further away from the aggregator than the second set of switch ports.

The present invention is directed to a circuit interrupting device including an actuator that provides an actuator stimulus upon the occurrence of the fault actuation signal. A circuit interrupter is positioned to electrically disconnect the first, second and third electrical conductors from each other upon the occurrence of the actuator stimulus. An automated test circuit is coupled to the circuit interrupting assembly. The automated test circuit is configured to automatically produce the simulated fault condition during a predetermined portion of an AC line cycle to determine whether the fault detection assembly is operational such that the fault detection assembly provides a fault detection signal without the circuit interrupter electrically disconnecting the first, second and third electrical conductors from each other. The automated test circuit is further configured to provide a device failure mode signal such that a plurality of the first, second or third electrical conductors are disconnected from each other if the fault detection signal is not detected within a predetermined time frame.

An apparatus includes a case capable of receiving a plurality of capacitive elements, each capacitor element having at least two capacitors, and each capacitor having a capacitive value. The apparatus also includes a cover assembly with a peripheral edge secured to the case. The cover assembly includes, for each of the plurality of capacitive elements, a cover terminal that extends upwardly from the cover assembly generally at a central region of the cover assembly. Each cover terminal is connected to one of the at least two capacitors of the respective one of the plurality of capacitive elements. The cover assembly also includes, for each of the plurality of capacitive elements, a cover terminal that extends upwardly from the cover assembly at a position spaced apart from the cover terminal generally at the central region of the cover assembly.

A pressure control reservoir includes a valve ball and a shaft which is movable to move the valve ball to open or close a fluid path leading to a fluid reservoir chamber. The shaft has a tip with a slant surface which has a peripheral edge of a polygonal shape with even numbers of vertices and is inclined to the longitudinal center line of the shaft. Such a polygonal geometry increases an entire or inclined length of the slant surface, which results in an increased range where an angle which the slant surface makes with a plane extending perpendicular to an axial direction of the tip is permitted to be increased without causing the point of contact between the valve ball and the slant surface to be shifted close to the tip of the slant surface when the tip of the shaft moves the valve ball.

A vehicle brake system includes a brake pedal unit (BPU) coupled to a vehicle brake pedal and including an input piston connected to operate a pedal simulator during a normal braking mode, and coupled to actuate a pair of output pistons during a manual push through mode. The output pistons are operable to generate brake actuating pressure at first and second outputs of the BPU. A hydraulic pressure source for supplying fluid at a controlled boost pressure is included. The system further includes a hydraulic control unit (HCU) adapted to be hydraulically connected to the BPU and the hydraulic pressure source, the HCU including a slip control valve arrangement, and a switching base brake valve arrangement for switching the brake system between the normal braking mode wherein boost pressure from the pressure source is supplied to first and second vehicle brakes, and the manual push through mode wherein brake actuating pressure from the BPU is supplied to the first and second vehicle brakes.

When a trailer is pulled by a tow vehicle where the trailer begins to sway to the left and right of the tow vehicle a large sway can result in loss of control of the trailer and or tow vehicle. The field of the present invention is a system and method of controlling a trailer sway which comprises determining the sway of the trailer utilizing an electronic sensor and independently applying the left and or right trailer brakes at varying levels to reduce trailer sway the traditional single braking signal power from the tow vehicle is separated into two independent braking signals for each of the left and right brakes. All brakes are applied whenever the traditional braking signal goes active where trailer battery power is utilized to independently activate the left and or right brakes during trailer sway.

A vehicle braking system includes a master cylinder having first and second outputs. First and second hydraulic braking circuits are provided between the respective master cylinder outputs and respective hydraulic wheel cylinders. A first pump provided in the first hydraulic braking circuit is operable to generate pressure and move hydraulic fluid within the first hydraulic braking circuit. A second pump provided in the second hydraulic braking circuit is operable to generate pressure and move hydraulic fluid within the second hydraulic braking circuit. A valving arrangement establishes fluid communication between the first pump and the second hydraulic braking circuit in a first configuration and prevents fluid communication between the first pump and the second hydraulic braking circuit in a second configuration.

A vehicle yaw stability control method and a vehicle yaw stability control apparatus are provided. The yaw rate {dot over (ψ)} of the vehicle is measured. A first reference yaw rate {dot over (ψ)}ref is set. A difference yaw rate Δ{dot over (ψ)} is set. Stabilizing braking intervention is triggered when a value of the difference yaw rate Δ{dot over (ψ)} exceeds limits defined by difference yaw rate threshold values Δ{dot over (ψ)}min, Δ{dot over (ψ)}max. Information regarding the shape of the road ahead of the vehicle is acquired. The reliability of the driver steering input δ is evaluated upon stabilizing braking intervention being triggered. In case the driver steering input δ is deemed unreliable a replacement reference yaw rate {dot over (ψ)}refroad is set based on the acquired road shape and a replacement difference yaw rate Δ{dot over (ψ)}road is set whereupon stabilizing braking intervention is performed based on the replacement difference yaw rate Δ{dot over (ψ)}road.

An electric power tool includes: a motor; a manipulation input receiving unit which receives a user manipulation input for rotating the motor; a mode changeover unit that has one manipulation portion which manipulated by the user; a rotation drive force transmitting unit that switches a transmission mechanism to one of the transmission mechanisms corresponding to the set position of the manipulation portion and transmits a drive force of the motor to a tool output shaft via the switched transmission mechanism; an electric signal output unit that outputs an electric signal corresponding to the set position of the manipulation portion; and a motor control unit that sets the control method of the motor to a control method preset for the electric signal, among a plurality of different types of control methods, based on the electric signal, and controls the motor by the set control method, based on manipulation by the user.

A control circuit for a blender provides low-cost power conditioning through the use of a high resistance which provides temporary power for operation of low-voltage logic circuitry and low-voltage switches for a time sufficient to switch the motor on, and a lower resistance which provides sufficient power for maintaining the motor on state indefinitely as instructed by the low-voltage logic circuitry. Low average power dissipation is provided by powering the low-voltage logic circuitry and low-voltage switches using the high resistance in a standby mode and switching in the lower resistance only when the motor is activated.

A power converting apparatus including a power converter that converts a DC voltage into an AC voltage and applies the AC voltage to an AC rotating machine and a control unit that controls the power converter based on an operation command from the outside is provided. The power converting apparatus includes: a first calculating unit that calculates and outputs, from a d-axis current detection value and a q-axis current detection value detected by the AC rotating machine and current command values based on the operation command, first voltage command values to the power converter, magnetic fluxes of the AC rotating machine, and an angular frequency; and a second calculating unit that sets, as an initial value, at least one of the magnetic fluxes and the angular frequency input from the first calculating unit and calculates and outputs second voltage command value to the power converter and an angular frequency.

An electric power tool includes a motor that rotary drives an output shaft; an operation unit to input a drive command of the motor; a torque setting device that sets an upper limit value of a rotational torque of the output shaft in accordance with a torque setting command; and a control device that drives the motor in one of a forward direction and a reverse direction in accordance with the drive command, and stops driving of the motor when the rotational torque of the output shaft has reached the upper limit value set by the torque setting device during driving of the motor. The torque setting device is configured to set the upper limit value such that the upper limit value during driving of the motor in the forward direction and the upper limit value during driving of the motor in the reverse direction are different.

Embodiments of the present method and system permit an effective method for determining the optimum selection of pulse width modulation polarity and type including determining machine parameters, inputting the machine parameters into a predicted duty cycle module, determining the optimum polarity of the pulse width modulation for a predicted duty cycle based on a pulse width modulation generation algorithm, and determining the optimum type of the pulse width modulation for a predicted duty cycle based on the pulse width modulation generation algorithm.

A lower limit value setting unit (52) variably sets a lower limit value (Vth) of a target voltage (Vh*) in a range of a voltage that is higher than the maximum value of voltages (Vb1, Vb2) of power storage devices and is not affected by a dead time provided for converters, based on temperatures (Tb1, Tb2) and required electric powers (Pb1*, Pb2*). A maximum value selection unit (53) sets the maximum value among the voltages (Vb1, Vb2) of the power storage devices and required voltages (Vm1*, Vm2*) of motor-generators, as the target voltage. A target voltage limiting unit (54) compares the target voltage with the lower limit value (Vth), and if the target voltage is lower than the lower limit value (Vth), the target voltage limiting unit (54) sets the lower limit value (Vth) as the target voltage (Vh*).

A device and method to determine the stopping rotor position of a washing machine motor includes an inverter, a permanent magnet synchronous motor, and an electronic motor controller. The controller determines the stopped rotor position of the motor by measuring induced currents in the stator field coils of the motor. While the motor is de-energized and slowly rotating, the controller directs the inverter to connect all of the stator field coils of the motor together. The stator field coils may be connected to a common D.C. rail, output from an A.C.-D.C. converter of the washing machine. In an embodiment, the controller determines the rotor position based on the polarities of current induced in the stator field coils. In another embodiment, the controller determines the rotor position based on the phase angle and angular frequency of the three phase currents, transformed into a stationary reference frame.