119 results about "Direct current" patented technology

A system includes a dispenser and a transmitter. The dispenser is configured to support and dispense product. The dispenser includes: a housing; an antenna disposed and configured to receive electromagnetic energy that originates from the transmitter; a power supply disposed within the housing and configured to convert the electromagnetic energy received at the antenna into DC (direct current) power; a dispenser mechanism configured and disposed to dispense the product from the dispenser on command; a controller disposed in operable communication with the power supply and the dispenser mechanism; and, an actuator disposed in operable communication with the controller. Upon actuation of the actuator, and upon presence of the DC power, the controller is responsive to facilitate action by the dispenser mechanism to dispense the product. The transmitter is configured to transmit electromagnetic energy and is disposed in operable communication with the dispenser.

A DC-based power system including: an AC power distribution system for providing AC power to a first node and a second node; a first converting system coupled to the first node that converts AC power to DC power and outputs the DC power to a first distributed bus bar; a second converting system coupled to the second node that converts AC power to DC power and outputs the DC power to a second distributed bus bar; a first set of DC/DC converters that steps down the DC power from the first distributed bus bar to a first stepped down DC voltage; a second set of DC/DC converters that steps down the DC power from the second distributed bus bar to a second stepped down DC voltage; and a critical load distribution system that is powered by both the first stepped down DC voltage and the second stepped down DC voltage.

Provided is a method of localizing rack-mounted computing devices, the method comprising: receiving, with a direct current (DC) power bus or via an Ethernet control network or data network, a request from a control unit for a rack computing device location; generating, with a sensor, output signals conveying information related to a location of the rack-mounted computing device; and sending, with the direct current (DC) power bus or via an Ethernet control network or data network, location information of the rack-mounted computing device.

The invention discloses a classified microgrid networking system based on terminal users and relates to the microgrid networking system. A user-stage microgrid is composed of a microgrid busbar, a distribution network busbar, a load switch, a power switch, an energy storage switch, a microgrid switch and a distribution network switch; the microgrid busbar is an alternating current or direct current busbar and is connected with a community-stage microgrid through the microgrid switch; the distribution network busbar is connected with a public distribution network through the distribution network switch; a conventional load is connected with the public distribution network; a compatible load is connected with the microgrid busbar or the distribution network busbar through the load switch; a distribution power supply is connected with the microgrid busbar through the power switch; and an energy storage device is connected with the microgrid busbar or the distribution network busbar through the energy storage switch. The classified microgrid networking system based on the terminal users is suitable for microgrid networking of terminal users who use photovoltaic or wind-solar hybrid equipment for distributed generation.

The invention provides a distribution transformer winding material detection system and method. The distribution transformer winding material detection system comprises a heating device, a curve acquisition device, a storage device and a matching device, wherein the heating device is for heating a to-be-detected distribution transformer winding; the curve acquisition device is for acquiring a detection curve, changing with the temperature of the winding, of the direct current resistance of the to-be-detected distribution transformer winding; the storage device is for storing a standard curve, changing with the temperature of the winding, of the direct current resistance of a standard distribution transformer winding made of a known winding material; and the matching device is used for matching the detection curve and the standard curve. According to the provided distribution transformer winding material detection system and method, the accuracy for field detection of the distribution transformer winding material is improved through matching of the temperature-resistance curve of the distribution transformer winding.

A wireless power transmission system includes a power transmission apparatus, a power reception apparatus, a load driving apparatus, and a power control apparatus. The power control apparatus includes a direct current power supply, a main control circuit, and a communicator. Each time an operation load to be achieved by the load driving apparatus changes, the main control circuit updates a load instruction value for the load driving apparatus and a control parameter for adjusting a voltage of first alternating current power, the control parameter being used by the power transmission apparatus to convert first direct current power into the first alternating current power. The power transmission apparatus includes an inverter circuit and a power transmission control circuit that determines the voltage of the first alternating current power on the basis of the control parameter updated by the power control apparatus and that controls the inverter circuit.

The invention discloses a chopper-type direct current detection method and a circuit. A forward voltage and a backward voltage of two ends of a shunt resistor are continuously collected in real time through a certain frequency. A sampling value of a first half of a chopper period and a sampling value of a second half of the chopper period in a same chopper period are calculated and influences of a low-frequency noise, an offset voltage and other noises on a detection result are eliminated. The detection circuit comprises a shunt resistor, a simulation switch, an amplifier, an analog-to-digital converter and a control unit. The simulation switch is connected in parallel to two ends of the shunt resistor. An input terminal of the amplifier is connected to an output terminal of the simulation switch. An input terminal of the analog-to-digital converter is connected to an output terminal of the amplifier. An input terminal of the control unit is connected to an output terminal of the analog-to-digital converter. An output terminal of the control unit is connected to a control signal input terminal of the simulation switch. On one hand, the control unit provides a digital signal to control switching of the simulation switch; on the other hand, according to digital forward and backward voltage signal, the control unit acquires a direct current detection value. A circuit structure provided in the invention is simple; test accuracy is high and cost is low.

The invention provides a power line carrier communication terminal device which comprises a power line carrier power adapter system used for allowing a strong-current power supply to be subjected to voltage reduction processing for outputting a low-voltage power supply, a signal modulation-demodulation system used for modulating/demodulating signals, and a signal transmission device used for transmitting low-voltage power supply and power line carrier signal, wherein the power output interface of the power line carrier power adapter system is connected with the power input interface of the signal modulation-demodulation system through the signal transmission device, so as to supply low-voltage direct current supply; and the power line carrier signal transmission interface of the power line carrier power adapter system is connected with the power line carrier signal transmission interface of the signal modulation-demodulation system through the signal transmission device, so as to realize the power line carrier signal communication. The device provided by the invention solves the electric safety problem, has an integrally reduced size and brings convenience for integration.

The invention discloses a neutral point direct current online measurement device for a transformer, which comprises a Hall sensor, a copper bar, a transmission fiber, a signal processing module arranged in a box body, a photoelectric power conversion module, a measurement signal photoelectric conversion module and a power laser launching circuit module, wherein the copper bar penetrates through the two sides of the box body; the copper bar in the box body is sleeved with the Hall sensor; the signal processing module is used for receiving an output signal of the Hall sensor, converting the output signal into an optical signal and outputting the optical signal into the measurement signal photoelectric conversion module; the measurement signal photoelectric conversion module is used for converting the inputted optical signal into an electrical signal to output; the photoelectric power conversion module is used for providing power for the Hal sensor and the signal processing module; and the power laser launching circuit module is used for inputting medium power laser for the photoelectric power conversion module. The neutral point direct current online measurement device adopts the optical fiber to supply the energy and transmit the signals, blocks an over-voltage transmission path and improves the measurement stability and the accuracy.

The invention relates to the electronic field, and discloses dimming method and circuit and a controllable silicon dimming circuit with the circuit. The method comprises the steps that a dimming signal is generated according to a current direct current input voltage signal; according to the dimming signal, the voltage average value signal of the dimming signal is generated; the fact that the dimming signal is currently in a positive half cycle or a negative half cycle is determined; when the dimming signal is currently in the positive half cycle, the voltage average value signal is compared with an output current feedback signal which represents the magnitude of the current output current, and a first comparison signal is output; a drive signal is output according to the first comparison signal; when the dimming signal is currently in the negative half cycle, the voltage average value signal is compared with an output current feedback signal which represents the magnitude of the current output current, and a second comparison signal is output; and a drive signal is output according to the second comparison signal. The application of the technical scheme is conductive to eliminating stroboflash.

The invention discloses a harmonic reactive power compensation device as well as a control method thereof. The device comprises a bypass cabinet, an input transformer, a control device and a power cabinet, the input transformer adopts three-phase input, poly-phase winding output and the zigzag connection means, the power cabinet comprises 3N identical power units, input terminals of R, S and T at a rectifier side of each power unit are connected at output sides of the transformer, so each power unit has an independent direct current power supply, and the power units are mutually insulated and secondary windings of the transformer are also mutually insulated; wherein, N power units form one phase by means of cascade connection, all the power units are in star connection or in triangle connection with three phases correspondingly and then are connected with a power network by a reactor. The invention has advantages of high reliability, flexible control, realizable harmonic reactive power continuous compensation, fast response speed, high net side power factors and low total current harmonic wave.

The invention discloses a circuit and a method for correcting the direct current (DC) offset part in output signals of a signal processing unit. The DC offset correcting circuit comprises a 1 bit quantizer, a control logic unit and a digital-to-analog converter, wherein, the 1 bit quantizer is coupled to the output terminal of the signal processing unit and used for receiving and detecting the DC offset part in the output signals so as to obtain quantitative information. The control logic unit is coupled to the 1 bit quantizer and used for sequentially setting one of a plurality of bits of a compensation value and updating the set bit according to the quantitative information. The digital-to-analog converter is coupled to the control logic unit and used for compensating the DC offset part in the output signals of the signal processing unit according to the compensation value.

The invention relates to a traction converter and control, fault processing and carrier phase shifting methods thereof. The traction converter comprises a first pre-charging loop and a second pre-charging loop that are connected with a secondary-side winding of the traction transformer respectively, a first four-quadrant rectifier module connected in series with the first pre-charging loop, a second four-quadrant rectifier module connected in series with the second pre-charging loop, an intermediate direct-current voltage loop with the input terminal connected with the output terminal of the first four-quadrant rectifier module and the output terminal of the second four-quadrant rectifier module, a first traction inverter module with the input terminal connected with the output terminal ofthe intermediate direct-current voltage loop, a second traction inverter module with the input terminal connected with the output terminal of the intermediate direct-current voltage loop, and an auxiliary inversion system with the input terminal connected with the output terminal of the intermediate direct-current voltage loop. According to the traction converter, the single four-quadrant rectifier module can work and the single traction inverter module can work; and the robustness is high, the fault rate is low, the size is reduced, and the cost is lowered.

The invention discloses an automatic control system for variable seeding and fertilization and a multifunctional planter. The multifunctional planter comprises a power system, a rack, a rotary-plowing and ditching system, a sowing system and a fertilizing system. The control system comprises ground wheels, a rotary code disc, a servo motor, a server and a single-chip microcomputer. A program of a function formula f (Q) = (n, v) of the sowing quantity (Q) of the planter versus the rotation speed n of the seeding axle and the forward speed v of the planter is written into the single-chip microcomputer. The ground wheels rows in drainage ditches so as to advance synchronously with the whole machine; the forward speed v of the ground wheels is measured in real time by using the rotary code disc; a pulse signal is sent to the single-chip microcomputer; the single-chip microcomputer calculates the rotation speed of the seeding axle according to the sowing quantity and the forward speed of the planter, and transmits a signal to the server; the server controls the output rotation speed of the direct-current servo motor by transmitting a pulse signal; and the servo motor directly drives rotation of the seeding axle. According to the invention, the overall structure is reasonable. The whole system forms a closed-loop control system and can meet the requirements of accurate and variable seeding and fertilization.

The invention relates to a portable rechargeable direct-current electric welding machine. A battery pack is connected to the outside of a shell and comprises a positive main wire, a positive sub-wire, a negative main wire and a negative sub-wire, wherein the positive main wire of the battery pack is connected with a weld handle connection terminal; the weld handle connection terminal is connected with a switch; the switch is connected with a voltage stabilizer; the voltage stabilizer is connected with a control panel; the control panel is connected with the voltage regulator; the voltage regulator is connected with the current regulator; the current regulator is connected with a contactor; the contactor is connected with a welding voltage meter; the welding voltage meter is connected with a welding current meter; the welding current meter is connected with the weld handle; the negative main wire of the battery pack is connected with a ground wire terminal; and the negative sub-wire of the battery pack is connected with the voltage stabilizer, the control panel, the voltage regulator, the current regulator, the contactor, the welding voltage meter and the welding current meter respectively. The portable rechargeable direct-current electric welding machine has low cost, is convenient to assemble, disassemble and carry, is not limited by a power supply, can work anytime and anywhere.

The invention discloses a module combined power quality conditioning system for a tractive power supply network, which belongs to the field of power quality improvement of a tractive power supply system. A power quality conditioner (101) is connected into a secondary output terminal of a traction transformer (66) and power supply arms of the traction power supply network in parallel, the energy of the two power supply arms is stored and exchanged through an energy storage capacitor at the direct current side of a power unit, and the balance of the three-phase current at the high-voltage side of the traction transformer (66) can be realized after the system is stabilized; and the power quality conditioner (101) can synchronously compensate the harmonic wave and the reactive power for each phase under the reasonable control strategy. The provided module combined power quality conditioning system for the tractive power supply network can directly run in the network without an industrial frequency transformer and an external reactor, realizes the high-voltage high-power input and the high-voltage high-power output by using the low-voltage power device and has the advantages of small occupied area, less loss and low cost.

The invention relates to a semiconductor lighting driving circuit which is compatible with a thyristor dimmer and a voltage input type dimmer. The semiconductor lighting driving circuit comprises a rectification filtering circuit, a power factor correction (PFC) circuit, a control circuit and a conversion circuit, wherein the rectification filtering circuit is used for converting an alternating current which comes from an alternating current power supply into a direct current; the PFC circuit is used for performing voltage reduction on the direct current; the control circuit is used for generating a pulse width modulation (PWM) control signal according to the direct current which is subjected to voltage reduction or an output voltage of the voltage input type dimmer; and the conversion circuit is used for supplying electric energy to a semiconductor lighting device according to the PWM control signal. The semiconductor lighting driving circuit is compatible with the thyristor dimmer and the voltage input type dimmer, can steadily operate in various kinds of dimming modes, and is high in generality. The semiconductor lighting driving circuit can independently operate, and the semiconductor lighting driving circuit and other circuit modules can conveniently form a product with high cost performance. Moreover, with the PFC circuit, the electromagnetic interference of the circuit can be remarkably reduced, so that the circuit operates more steadily and more reliably.

The invention discloses a refrigerator load control monitoring system in the technical field of load monitoring. The refrigerator load control monitoring system comprises a refrigerator control plate; output ends of a refrigeration illuminating lamp, a temperature change door decorating lamp, a refrigeration air door heating wire and a temperature change air door heating wire are electrically connected with an input end of a 12-V direct-current voltage detecting module; an output end of a fan is electrically connected with an input end of a fan rotating speed monitoring module; a detecting plate detects a working state of a load; data is transmitted to an upper computer in real time; the upper computer displays and stores the data in a chart form to conveniently analyze and view the data; refrigerator control rules can be set and detected to reduce the analysis workload of the testing data; testers can leave during testing; the data is automatically recorded to conveniently view later; the upper computer can automatically judge if each logic relation and load operating state in refrigerator control accord with the specification requirements; each control relation can be opened or closed; and various parameters can be modified.

The invention discloses a driving wheel system capable of realizing universal rotation. The driving wheel system comprises a wheel (1), a wheel axle (2), a wheel axle tapered roller bearing (3), a wheel axle housing (4), a check washer (5) for a wheel axle disc nut, the wheel axle disc nut (6), a direct-current motor (7), a motor fixing housing (8), a steering shaft (9), a rotating shaft sleeve (10), a frame (11), a rotating shaft tapered roller bearing (12), a check washer (13) for a rotating shaft disc nut, and the rotating shaft disc nut (14). When a torque is applied to the steering shaft (9), the steering shaft (9) drives the motor fixing housing (8), the direct-current motor (7), the wheel axle housing (4), the wheel axle (2) and the wheel (1) to rotate relative to the frame (11) so that independent steering is realized. A vehicle can be steered in situ and driven linearly, obliquely, horizontally and the like so as to operate in a narrow space.