598 results about "Resistive load" patented technology

Exemplary systems and methods are provided for collecting / harvesting direct current (DC) power received from a power source(s). The system comprises a controlled impedance power controller comprises a power converter configured to present a positive equivalent resistive load to the at least one power source over a range of input power levels. Exemplary systems and methods are provided for collecting radio frequency (RF) power. An exemplary system comprises at least two rectenna elements, a power controller, and a DC combining circuit. The DC combining circuit is associated with the at least two rectenna elements and the DC combining circuit is configured to dynamically combine the at least two rectenna elements in one of a plurality of series / parallel configurations. The power controller is configured to control the DC combining circuit to achieve a desired overall power output from the at least two rectenna elements.

A stationary exercise machine includes a system for electronically controlling a pedal resistance so as to simulate the riding of a road-going bicycle. The exercise machine includes a control system that monitors pedal velocity and that controls the resistive load generated by an electronically-controlled resistance mechanism. In one example, an electromagnetic device may vary a resistive load placed on a flywheel, which, in turn, varies the pedal resistance experienced by a user. When the user increases the pedal velocity, the resistance mechanism increases the resistive load. When the user decreases the pedal velocity, the resistance mechanism decreases the resistive load. In another example, the resistance mechanism varies the resistive load based on a gear selection by the user. The control system may also take into account other factors, such as the grade of the simulated ride, simulated wind resistance, or other frictional forces when calculating the resistive load.

A decision feedback equalizer, transceiver, and method are provided, the equalizer having at least one comparator, the at least one comparator comprising a first stage, comprising a main branch having two track switches with a resistive load, an offset cancellation branch, a plurality of tap branches with transistor sizes smaller than the main branch, in which previous decisions of the equalizer are mixed with the tap weights using current-mode switching, and a cross coupled latch branch; and a second stage, comprising a comparator module for making decisions based on the outputs of the first stage and a clock input, and a plurality of flip-flops for storing the output of the comparator module.

Exemplary systems and methods are provided for collecting / harvesting direct current (DC) power received from a power source(s). The system comprises a controlled impedance power controller comprises a power converter configured to present a positive equivalent resistive load to the at least one power source over a range of input power levels. Exemplary systems and methods are provided for collecting radio frequency (RF) power. An exemplary system comprises at least two rectenna elements, a power controller, and a DC combining circuit. The DC combining circuit is associated with the at least two rectenna elements and the DC combining circuit is configured to dynamically combine the at least two rectenna elements in one of a plurality of series / parallel configurations. The power controller is configured to control the DC combining circuit to achieve a desired overall power output from the at least two rectenna elements.

[Problems] To provide a non-contact power feeder that is high efficient and high power factor and has no load dependence.[Means for Solving Problems] A series capacitor Cs1 is connected to a primary winding 1 driven by an AC power supply 3 and a parallel capacitor Cp2 is connected to a secondary winding 2. The capacitance Cp is set to Cp≈1 / {2πf0×(x0+x2)} and the capacitance Cs converted to the primary side is set to Cs≈(x0+x2) / {2πf0×(x0×x1+x1×x2+x2×x0)}, where f0 is the frequency of the power supply, x1 is a primary leakage reactance of the primary winding 1, x2 is a secondary leakage reactance of the secondary winding 2 converted to the primary side and x0 is an excitation reactance converted to the primary side. By setting Cp and Cs to the above values, the transformer of the non-contact power feeder is substantially equivalent to an ideal transformer. If it is driven by a voltage type converter, the output voltage (=load voltage) becomes substantially constant voltage regardless of the load. In case of a resistive load (ZL=R), the power factor of the power supply output always remains 1 even if the load may vary.

A system and method for controlling a vehicle for regenerative braking facilitates decreasing the warm-up time of the fuel cell stack from start-up to full electrical power generation capacity. A controller detects a starting time of a fuel cell stack associated with a vehicle. A drive motor generates electrical energy during braking or deceleration of the vehicle, where the drive motor is mechanically coupled to at least one wheel of the vehicle. A controller refers to or determines a time window following the starting time. The switching unit routes the electrical energy to a resistive load associated with a heat exchanger thermally coupled to a fuel cell stack of the vehicle if the electrical energy is generated during the time window.

A voltage controlled oscillator ("VCO") circuit capable of generating signals with reduced jitter and / or low-phase noise is provided. One embodiment provides a plurality of cascaded VCO cells, where each VCO cell can include a source coupled differential pair, a bias transistor connected to the differential pair for biasing the differential pair, a resistive load pair connected to the differential pair, and a voltage controlled capacitor pair or varactor pair connected to the differential pair. The varactors provide control over the frequency of the oscillations produced by the VCO circuit in combination with a control voltage. A phase frequency detector combined with a charge pump and loop filter provide the control voltage.

The invention provides a design method of an LED (light-emitting diode) dimming driving switching power supply applied to various traditional dimmers. According to the design method, the LED driving power supply achieves the resistive load input-output characteristics similar to those of an incandescent light bulb, so that LED lights (semiconductor LEDs) can be well suitable for dimming of the traditional dimmers (including traditional dimmers adjusting the phases of conduction angles through leading edge phase cut and traditional dimmers adjusting the phases of conduction angles through trailing edge phase cut, wherein silicon controlled dimmers are dimmers adjusting the phases of conduction angles through leading edge phase cut) and be used in indoor places where the traditional dimmers are needed for dimming. The LED dimming driving switching power supply designed according to the design method provided by the invention comprises a dimmer starting circuit loop, a rectifying circuit, a phase detection and isolation circuit, a phase cut detection circuit, a power-factor correction circuit, a switching power supply circuit and an LED current control circuit.

An intermittent microwave energy delivery system for use in testing microwave energy systems and devices and for use in performing medical procedures including a microwave energy source configured to provide a continuous microwave energy signal, an energy delivery network configured to intermittently transmit a portion of the continuous microwave energy signal, a resistive load configured to dissipate the microwave energy signal; and a switching network configured to switch the continuous microwave energy signal between the microwave energy network and the resistive load. The continuous microwave energy signal is time proportioned between the energy delivery network and the resistive load.

Systems for making impedance adjustments that will auto-tune a communication path is disclosed. The method can utilize time domain reflectometry (TDR) to acquire data about impedance mismatches and can adjust the termination impedances based on the acquired data. A system is also disclosed that has an isolator to decouple a first adjustable resistor from a transmission path in a first mode and couple the first adjustable resistor to the path in a second mode. The system can have a test transmitter to create a first current on the path in the first mode and to create a second current having twice the current in a second mode, wherein a detector can detect a first voltage during the first mode and a second voltage in the second mode as the first adjustable resistive load is adjusted in the second mode until it reaches a value matching the first voltage detected in the first mode.

Hydraulic systems and methods for using such systems in a variety of machinery, including but not limited to machines having multiple functions performed by one or more hydraulic circuits. The systems enable valves and actuators within the systems to reconfigure themselves so that flow from assistive loads on one or more actuators can be used to move one or more other actuators subjected to a resistive load.

A procedure for starting up a fuel cell system that is disconnected from its primary load and that has air in both its cathode and anode flow fields includes a) connecting an auxiliary resistive load across the cell to reduce the cell voltage; b) initiating a recirculation of the anode flow field exhaust through a recycle loop and providing a limited flow of hydrogen fuel into that recirculating exhaust; c) catalytically reacting the added fuel with oxygen present in the recirculating gases until substantially no oxygen remains within the recycle loop; disconnecting the auxiliary load; and then d) providing normal operating flow rates of fuel and air into respective anode and cathode flow fields and connecting the primary load across the cell. The catalytic reaction may take place on the anode or within a catalytic burner disposed within the recycle loop. The procedure allows start-up of the fuel cell system without the use of an inert gas purge while minimizing dissolution of the catalyst and corrosion of the catalyst support during the start-up process.

An active pixel sensor for digital imaging comprises a detector, a readout circuit, and a resistive load. The detector is integrated with the readout circuit and the readout circuit has a plurality of amorphous silicon based thin-film transistors (TFTs). The readout circuit is embedded under the detector to provide a high fill factor. A signal charge is accumulated on a pixel capacitance during an integration mode and is transferred to an external electronics for data acquisition via the readout circuit during a readout mode. An output current from the readout circuit is converted to a voltage through the resistive load. The resistive load may be a thin-film transistor operated in a saturation regime and having a width larger than a length in size. The active pixel sensor amplifies an on-pixel sensor input signal to improve a noise immunity of sensitive sensor input signals to external noise sources and its linearity together with a fast pixel readout time.

An exercise machine that varies a resistive load based on sensed changes in intensity of exercise. In one example, an electronic control system of a stationary bicycle adjusts a flywheel resistive load based on changes in the user's pedal cadence. During the exercise routine, subsequent increases or decreases in the pedal cadence cause, respectively, increases or decreases in the flywheel resistive load. In addition, the control system may execute the exercise routine after actuation of a single input key. In another embodiment, the user may simply start to exercise. The electronic control system may calculate a default flywheel resistive load based on initialization parameters, such as demographic data and / or exercise preferences.

The invention dsiclsoes a microgrid system with an asymmetric non-linear load and a power balancing control method. The system comprises a plurality of DG units connected in parallel and line impedors connected with all DG units. The line impedors are connected to a microgrid bus by PCC points. A three-phase balancing resistive load, an asymmetric linear load, and a diode rectifier non-linear load of a load unit are connected to the microgrid bus by PCC points. A measurement module for measuring voltage fundamental wave positive sequence and negative sequence components and harmonic wave components of the PCC points is also connected to the microgrid bus. The microgrid bus is connected with a 10-kV main power grid by a static switch and a transformer successively. According to the invention, reactive and harmonic power balancing of the microgrid is realized by using a selective virtual impedance based on the virtual fundamental positive and negative sequence impedance and the virtual variable harmonic impedance; a harmonic and unbalancing voltage compensation controller enables equal division of an unbalanced power and a harmonic power to be realized; and a problem of unbalancing of the harmonic wave and the voltage of the microgrid can be solved.

The present invention relates to a ring oscillator including a delay stage, the delay stage includes a differential pair of input transistor, a variable resistive load coupled to the transistor, a differential output between the variable resistive load and the corresponding input transistor, a variable current source coupled to the differential pair of transistors for variably setting a bias current through the differential pair of transistors, and an input coupled to the variable resistive load and the variable current source for receiving an configuration signal, wherein the variable resistive load and the variable current source are changed in response to the configuration signal, wherein the bias current of the variable current source increases and the variable resistive load decreases, and vice versa.

A stationary exercise machine includes a system for electronically controlling a pedal resistance so as to simulate the riding of a road-going bicycle. The exercise machine includes a control system that monitors pedal velocity and that controls the resistive load generated by an electronically-controlled resistance mechanism. In one example, an electromagnetic device may vary a resistive load placed on a flywheel, which, in turn, varies the pedal resistance experienced by a user. When the user increases the pedal velocity, the resistance mechanism increases the resistive load. When the user decreases the pedal velocity, the resistance mechanism decreases the resistive load. In another example, the resistance mechanism varies the resistive load based on a gear selection by the user. The control system may also take into account other factors, such as the grade of the simulated ride, simulated wind resistance, or other frictional forces when calculating the resistive load.

Described herein is, for example, a battery or capacitor over voltage (overcharge) and under-voltage protection circuit, that, for example, is adapted to not draw current from the battery or capacitor to be charged unless charge energy is detected and to not charge an energy storage device when an over-charge condition is sensed. The protection circuit may, for example, not be turned on unless an over voltage condition is present. Incoming energy to the system can be shunted to ground via a shunt load of various types including resistive loads and active components such as a zener diode. In some embodiments, no switching of the inbound power is required. Within limits, no regulation of inbound power is needed. When inbound power is sufficient to charge the battery or capacitor, regulation can occur via the applied shunt regulator if overcharge voltage conditions exist. Either type of charge source, voltage or current, can be used to provide charge energy. Combining said battery or capacitor over voltage (overcharge) and under-voltage protection circuit with electronic loads, such as wireless sensors, may lead to autonomously-powered wireless sensor systems.

A digitally implemented slew rate controller for a power supply and a power supply having the same. An output up-programming signal is provided that enables the power supply to change an output voltage and current at a maximum rate which does not engage the protection circuits which are employed to protect components of the power supply. The maximum rate of change decreases as the output voltage increases. The up-programming speed of the power supply output optimizes the output by considering that an amount of output current available for charging an output capacitor of the power supply will decrease as the output voltage increases for a resistive load. An output down-programming control signal enables a discharge device to dissipate heat with a constant power characteristic, which will minimize a time required to reduce the output voltage while not exceeding a maximum power dissipation rating of the discharge device.

A current-steering type digital-to-analog converter (DAC) is disclosed. The DAC includes a first sub-DAC, a second sub-DAC and a controlling device. Both the first sub-DAC and the second sub-DAC are configured to receive input signals. The controlling device selectively and periodically sends output signals of either the first sub-DAC or the second sub-DAC to a resistive load while sending output signals of the remaining one of the two sub-DACs to a dummy resistive load. An output of the DAC is provided at the resistive load.

An exercise machine has a user support movement arm rotatably mounted on a support frame for rotation about a first pivot axis, and a user support assembly pivotally connected to the movement arm for rotation about a second pivot axis so that the user support assembly rotates in two directions about different pivot axes. An exercise arm pivotally mounted on the frame is linked to the user support assembly or user support movement arm so that movement of the exercise arm automatically moves the user support assembly. Movement about one pivot axis may be a free pivoting, non-resisted movement while movement about the other pivot axis may be associated with a resistive load.

An apparatus for providing a dynamically variable resistive load during exercise includes a wheel unit, a resistance generator, a torque transfer device, an angle measuring device, and a control unit. The wheel unit rotates in response to exertion of a user-applied force during an exercise stroke. The resistance generator generates a resistive torque for resisting rotation of the wheel unit when the user-applied force is exerted. The torque transfer device transfers a fraction of the resistive torque from the resistance generator to the wheel unit. The angle measuring device detects angular rotation of the wheel unit during each exercise stroke. The control unit, in accordance with the angular rotation of the wheel unit during a current exercise stroke, controls the torque transfer device to adjust the fraction of the resistive torque that is transferred to the wheel unit.

A power supply for a capacitive-resistive load includes plural paralleled phase correcting modules together with current sharing controllers for tending to equalize their currents. Each module is provided with a diode, poled to prevent forward current from flowing in the return current path, for aiding in equalizing module currents. Surge currents are reduced by a single saturable reactor coupled to the combined outputs of current sharing controllers, thereby avoiding the need for soft-start in each controller. A precharging path extends from a source of pulsating direct voltage to the load, for precharging the load capacitance at turn-on.

To provide adequate compensation for a wide range of output loads, a low dropout (LDO) regulator has an amplifier, a pass transistor, a voltage divider, a compensation network, and a control circuit. The amplifier outputs a comparison result according to a reference signal and a feedback signal. The pass transistor generates an output current based on the comparison result of the amplifier. The voltage divider generates the feedback signal according to the output current. The compensation network couples the output of the pass transistor to a low-impedance node of the amplifier, and has a compensation capacitor and a variable resistor coupled to the compensation capacitor. The control circuit is coupled to the input of the pass transistor and to the variable resistor for controlling resistance of the variable resistor according to the output current of the pass transistor.

A subwoofer cabinet having a volume less that 1 ft3 axially aligned openings in opposed cabinet walls; first and second cages mounted on respective ones of the walls in alignment with the openings; a voice coil driven driver including an annular 225 oz. magnet affixed to the first cage; a stationary pole piece extending through the magnet and defining a magnetic gap therebetween; a voice coil mounted on a cylindrical voice coil former positioned within the gap; a cone affixed to one end of the former; a first flexible surround secured to the outer end of the cone and attached at its periphery to the first cage; a flexible spider secured to the former and at its outer periphery to the first cage; a mass driven driver including a 1.7 lb. mass; a second flexible surround secured to the mass and to the second cage; a flexible spider attached to the second cage and to the mass; both surrounds having a uniform thickness of at least 0.1″, an edgeroll having a diameter of at least 1.5″, and capable of standing off internal pressures of 1.5 lbs. / in2 to 3 lbs. / in2; a drive amplifier capable of delivering 2,700 watts to a nominal 4 ohm resistive load and swinging 104 volts for delivering (+)-v and (−)-v drive signals to the voice coil for driving the voice coil driven driver through a peak-to-peak stroke of about 2.5″ while generating a large back emf sufficient to counter the applied emf and minimize current flow in the voice coil.

The invention relates to the field of electrical equipment detection, in particular to a full-performance detecting system of a magnetic latching relay and a detecting method of the full-performance detecting system of the magnetic latching relay. The detecting system comprises a main control panel, an auxiliary control panel and a resistive load box, wherein the auxiliary control panel is communicated with the main control panel through a network port, the auxiliary control panel controls the resistive load box to work by controlling an air switch, and the main control panel is connected with the magnetic latching relay. An ongoing full-performance test of the magnetic latching relay comprises an initial operation voltage, a returned value voltage test, an operation time test, a four probe method and high current method coil resistance test, a contact temperature-rise test, a mechanical life test, an electrical endurance test and an overload test. The full-performance detecting system is simple in wiring, capable of automatically finishing an electrical performance test, a safety performance test and a service life test without manual intervention, comprehensive in test items, and simple in test process.

This bolometric detector for electromagnetic radiation comprises: a receiving antenna (1) intended for collecting electromagnetic radiation and thus ensuring electromagnetic coupling; a resistive load capable of converting the electromagnetic power collected into heating capacity; a thermometric element (4) connected to the receiving antenna (1) via the resistive load and thermally isolated from a support substrate (2), capable of accommodating an electronic circuit that includes means of electric excitation (stimuli) and means of pre-processing the electric signals generated by said detector. The receiving antenna (1) is itself isolated from the support substrate (2).

A protection circuit of an LCD panel. The LCD panel includes a display cell coupled between a data electrode, a gate electrode and a common electrode. A switch includes a first terminal and a second terminal. The first terminal is coupled to the data electrode, the gate electrode or both. The switch is turned on when a voltage level of the first terminal or the second terminal exceeds a threshold voltage. An ESD protection circuit includes a capacitive load and a resistive load, coupled between the second terminal and the common electrode.

An exercise machine that varies a resistive load based on sensed changes in intensity of exercise. In one example, an electronic control system of a stationary bicycle adjusts a flywheel resistive load based on changes in the user's pedal cadence. During the exercise routine, subsequent increases or decreases in the pedal cadence cause, respectively, increases or decreases in the flywheel resistive load. In addition, the control system may execute the exercise routine after actuation of a single input key. In another embodiment, the user may simply start to exercise. The electronic control system may calculate a default flywheel resistive load based on initialization parameters, such as demographic data and / or exercise preferences.