79191 results about "Direct current" patented technology

The present invention relates to a method for control of a direct current motor in one or several fan units, each comprising a fan, which method comprises: generation of a control signal from a first control unit which is external in relation to the said fan unit; transmission of the said control signal to the said fan unit; reception of the transmitted control signal in the said fan unit; interpretation of the said control signal in a second control unit which is arranged in association with the said fan unit; and generation, in the said second control unit, of a supply signal for the said direct current motor, on the basis of the control signal generated by the first control unit and received in the fan unit and on the basis of a supply voltage. According to the invention, the method comprises transmission of the control signal together with the supply voltage over a shared communication link, with the control signal being superposed on the supply voltage. The invention also relates to an arrangement for such control. By means of the invention, improved control is obtained of a motor that can be utilized in a ventilated seat in a vehicle.

An inductive power systems transfers energy by inductively coupling a source coil on a power source to a receiver coil on a power portion of a power adapter. The source current is received in the power adapter and converted to direct current for transmission to a computer system. Wireless communication between a power source and the power adapter is provided. A wireless communication arrangement provides for authentication of devices that are allowed by a source to be powered.

A motor driving method for driving a direct-current (DC) motor, designed for avoiding a reverse current induced by the Back Electromotive Force (BEMF), includes providing a driver circuit for driving the DC motor; comparing a signal level of a terminal of the DC motor and a predetermined voltage value to produce a comparing result; and controlling a specific lower gate switch to avoid the occurrence of a reverse current of the DC motor according to the comparing result.

A modular apparatus for and method of alternating current photovoltaic power generation comprising via a photovoltaic module, generating power in the form of direct current; and converting direct current to alternating current and exporting power via one or more power conversion and transfer units attached to the module, each unit comprising a unitary housing extending a length or width of the module, which housing comprises: contact means for receiving direct current from the module; one or more direct current-to-alternating current inverters; an alternating current bus; and contact means for receiving alternating current from the one or more inverters.

Disclosed herein is an LED light. The LED light comprises a socket electrically connected to a receptacle, and a cooling fan for forcibly circulating air. The cooling fan is received in a main body, which has a plurality of radial partition walls formed on the outer peripheral surface thereof in such a manner as to be spaced apart from one another with a gap having a slit shape for ventilation. A plurality of LEDs is attached to the outer periphery and / or the inner leading edge of the main body. A circuit board is provided to control the light such that an alternating current supplied from the socket is rectified into a direct current, which is supplied to the cooling fan and the LED.

Disclosed herein is a portable charger for a mobile phone. The portable charger includes a front housing, a rear housing, a belt clip, a fastening unit, a pair of clamps, a release button, an interface connector, a secondary battery and a charge control unit. The portable charger is easy to carry, can easily charge the battery of the mobile phone with direct current power charged in a secondary battery, and can simultaneously charge the secondary battery and the battery of the mobile phone using a travel adaptor.

An inverter device includes a plurality of switching circuits in which first switching elements including Si semiconductors and second switching element including WBG semiconductors having ON resistance smaller than that of the first switching elements and having switching speed higher than that of the first switching elements are connected in parallel. The inverter device includes a converting circuit that converts a direct-current voltage into a desired alternating-current voltage and a driving unit that generates a plurality of driving signals for respectively turning on and off the switching circuits. The inverter device includes, for each of the switching circuits, a gate circuit that, based on the driving signals, turns on the second switching element later than the first switching element and turns off the first switching element later than the second switching element.