282results about How to "Reduce ripple" patented technology

A power control circuit is provided containing a switch array, which includes segmented switches, a flying capacitor, an output voltage terminal, a feedback loop, and a digital voltage regulator block. The digital voltage regulator block includes an A / D converter, an encoder, an add-subtractor, and a gate logic. These power control circuits do not include pass transistors. A method is also provided, where the charge pumps of the power control circuit are operated in two-phase cycles including a charging phase and a pumping phase. The power control circuit is controlled in both of these phases, thereby reducing the ripple of the output voltage.

A system and method are provided for actively reducing ripple in a supply voltage provided by a switched mode power supply. In general, active ripple reduction circuitry operates to sense the ripple in the supply voltage to provide a signal indicative of the ripple. The signal indicative of the ripple is inverted and provided to the output of the switched mode power supply to substantially reduce or eliminate the ripple in the supply voltage.

We describe a photovoltaic (PV) panel system comprising a PV panel with multiple sub-strings of connected solar cells in combination with a power conditioning unit (microinverter). The power conditioning unit comprises a set of input power converters, one connected to each sub-string, and a common output power conversion stage, to provide power to an ac mains power supply output. Integration of the micro-inverter into the solar PV module in this way provides many advantages, including greater efficiency and reliability. Additionally, embodiments of the invention avoid the need for bypass diodes, a component with a high failure rate in PV panels, providing lower power loss and higher reliability.

In a gate driving circuit and a display apparatus, the gate driving circuit comprises a plurality of stages. At least one of the stages comprises a pull-up section responsive to a first node signal; a pull-down section responsive to a second input signal; a discharging section discharging the first node signal in response to the second input signal; a first holding section responsive to the first clock signal, maintaining the first node signal at the off-voltage; and a second holding section responsive to the second clock signal, maintaining the first node signal at the off-voltage. The second holding section has a greater transistor width-to-length ratio than the first holding section. Therefore, an abnormal gate-on signal is less likely to occur, reducing driving defects of the display apparatus.

In a switching regulator, a peak current value of an inductor current iL corresponding to a critical current is obtained by {(Vin−Vout) / Vin×Vout / L×Ts}, where Ts is the frequency of clock signals CLK constituting set pulses generated at predetermined timings by an oscillating circuit 9. Accordingly, by setting a reference voltage VLL as (Vout / L×Ts / rs), the peak current value of the inductor current iL when the load current has decreased is set to be the peak current value of the inductor current iL corresponding to the critical current. Therefore, simply by setting the reference voltage VLL in advance, the peak current of the inductor current iL when the load current has decreased is set to be the peak current value of the inductor current iL corresponding to the critical current.

In a pulse frequency modulated (PFM) voltage regulator, a PFM switching controller is provided to generate a PFM switching signal for converting a DC voltage source to an output voltage. A minimum OFF-time controller provides the PFM switching signal with a minimum OFF-time. In response to the output voltage, a feedback circuit generates a feedback signal. When the output voltage is lower than a predetermined target voltage, an OFF-time prolonging circuit prolongs the minimum OFF-time in response to the feedback signal. In other words, a time of delivering energy to a capacitor from an inductor may be prolonged by the OFF-time prolonging circuit. Therefore, a ripple of the output voltage is effectively reduced when the PFM voltage regulator is operated in a heavy loading condition.

A switching power supply circuit in which a series circuit comprising a resistive element and a capacitive element is provided in a parallel configuration with an inductor which supplies a load current to a load circuit, a voltage comparator having first and second threshold voltages discriminates a voltage obtained from a mutual connecting point of the series circuit therefrom and controls a switch element for supplying a current to the inductor, thereby varying the current supplied to the inductor in accordance with a variation in the load current is combined with a series power supply circuit which shares the load current of the load circuit.

What is described here is an array for the contact-less transmission of electrical signals or energy, respectively, from at least one transmitter to several receivers. The invention is characterised by the provisions that each transmitter comprises an AC voltage or current source, respectively, as well as a plurality of inductive coupling elements supplied from said source, which elements are supplemented by at least one capacitor to form elements capable of resonating, and that furthermore one control element is that controls said AC voltage or current source, respectively, in such a way that the latter operates on a resonant frequency of said elements capable of resonating

The invention proposes a direct current voltage conversion circuit which can operate as a step-up circuit, a step-down circuit, or operate as a step-up or step-down circuit depending on the modes of operation.

An axial gap dynamoelectric machine comprises first and second stators disposed coaxially with an intermediate rotor. The stators are selectively aligned with an axial offset between the positions of their respective teeth and slots. The stators comprise toroidal cores having laminated layers composed of a material selected from the group consisting of amorphous and nanocrystalline metals and optimized Fe-based alloy. Optionally, the machine further comprises misalignment means for adjusting the offset of the stators. Adaptive adjustment permits the machine to be operated to in a mode that reduces the back EMF of the motor, allowing constant voltage to be maintained as speed is increased. Reducing back EMF also allows a wider range of operating speed, especially in combination with use of high pole counts. Alternatively, the machine can be operated, e.g. at lower speed, in a constant torque mode. The machine may exploit the high pole count achievable by use of improved soft magnetic materials. Also provided are techniques for reducing torque ripple during operation, and also for using the stator offset in combination with a dual full wave bridge rectifier arrangement.

This invention features a more compact and higher reliability power source system for computing loads, the system including a high voltage DC bus connected to a number of DC sources each connected to the high voltage DC bus by a switch configured to deliver to the high voltage DC bus the DC source with the highest DC voltage, a low voltage DC bus connected to the computing loads, and a power supply including a number of DC / DC converters connected in parallel between the high voltage DC bus and the low voltage DC bus, and a controller configured to modulate each DC / DC converter to convert the high voltage on the high voltage DC bus to a low voltage output on the low voltage DC bus.

The objective of this invention is to reduce the current flowing through the inductance element in a step-up / step-down DC—DC converter and to control the ripple in the output voltage. In the DC—DC converter, four states, that is, the first state [1] of (M1, M2)=(off, on) and (M3, M4)=(on, off), the second state [2] of (M1, M2)=(on, off) and (M3, M4)=(off, on), the third state [3] of (M1, M2)=(on, off) and (M3, M4)=(on, off), and the fourth state [4] of (M1, M2)=(off, on) and (M3, M4)=(off, on) are repeated in a prescribed order, preferably in the order . . . [1]→[4]→[2]→[3]→[1] . . . or . . . [1]→[3]→[2]→[4]→[1] . . . .

A gate drive circuit includes a shift register having stages connected to each other in series. An (m)-th stage (‘m’ is a natural number) includes an output part, a discharging part, a first holding part and a second holding part. The output part outputs the first clock signal as a gate signal in response to a first clock signal provided from an external device and discharges the gate signal in response to a second input signal. The output part includes a first transistor having a first channel length. The discharging part discharges a signal of the first node to the second voltage level. The first holding part maintains a signal of the first node at a level of the gate signal, and is discharged to the second voltage level. The first holding part includes a second transistor having a second channel length that is longer than the first channel length. The second holding part maintains a signal of the first node at a level of the second voltage level.

The present invention relates to a driver for a string (STi) of series arranged light emitting diodes (D1i, D2i, D3i) of which at least two emit light having different spectra. The driver comprises a main power supply (PAi) which has outputs coupled across the string (STi) to supply a main current (IAi) to the string (STi). A secondary power supply (PBi) is coupled to at least one of junctions (J1i) between successive light emitting diodes (D1i, D2i) in the string (STi) to supply or withdraw a delta current (IBi) from the junction (J1i). The delta current (IBi) is at least a factor 5 smaller than the main current (IAi). A controller (CO) controls the secondary power supply (PBi) to generate the delta current (IBi) to obtain a desired spectral composition of the mixed light emitted by the string (STi).

Disclosed are a three-phase wireless power transfer (WPT) system and three-phase wireless rechargeable unmanned aerial vehicle (UAV) system based on the same. Three power receiving coils, including resonators, are installed at the ends of three landing leg of the UAV. A three-phase power converter installed in the UAV receives the three-phase AC induction current induced in three power receiving coils, including resonators, converting the three-phase AC induction current into a DC current to be charged in a battery. A three-phase power wireless charging apparatus wirelessly transfers three-phase power from three power transmitting coils to the three power receiving coils of the UAV when the three landing legs land on three coil seating units provided on a charging platform. A magnetic flux leakage shielding coil may be provided to prevent magnetic flux leakage from approaching the UAV. The power transfer efficiency is excellent, and electromagnetic interference can be also reduced.

A switching power supply circuit in which a series circuit comprising a resistive element and a capacitive element is provided in a parallel configuration with an inductor which supplies a load current to a load circuit, a voltage comparator having first and second threshold voltages discriminates a voltage obtained from a mutual connecting point of the series circuit therefrom and controls a switch element for supplying a current to the inductor, thereby varying the current supplied to the inductor in accordance with a variation in the load current is combined with a series power supply circuit which shares the load current of the load circuit.

In a ladder type filter, a first inductor is connected in series with a parallel resonator. A second inductor is connected in parallel to a series resonator. The resonant point of the parallel resonator having the first inductor connected in series and the anti-resonant point of the series resonator developed on the lower frequency side of the resonant point of the series resonator, caused by the second inductor connected in parallel, substantially coincide with each other.

In a gate driving circuit and a display apparatus, the gate driving circuit comprises a plurality of stages. At least one of the stages comprises a pull-up section responsive to a first node signal; a pull-down section responsive to a second input signal; a discharging section discharging the first node signal in response to the second input signal; a first holding section responsive to the first clock signal, maintaining the first node signal at the off-voltage; and a second holding section responsive to the second clock signal, maintaining the first node signal at the off-voltage. The second holding section has a greater transistor width-to-length ratio than the first holding section. Therefore, an abnormal gate-on signal is less likely to occur, reducing driving defects of the display apparatus.

In a non-volatile memory, charge pumps are used to provide high voltages needed for programming memory cells that have floating gate structures. Charge pumps have a series of voltage multiplier stages in series to boost voltage. These charge pumps must rapidly charge a load to a high voltage and then maintain a voltage with a high degree of stability. Techniques for achieving both of these goals are presented. In one aspect, a charge pump has two operating states, one to charge a load rapidly and a second to maintain a voltage on a charged load with high stability. These states are achieved by changing the current output-from a high current during charging to a low current to maintain the voltage. This is done by changing the capacitance used in the individual voltage multiplier stages. In another aspect, two different current levels are produced by changing the voltage used to charge the capacitors of the voltage multiplier stages.

In a control circuit which turns on / off the switching device elements included in a synchronous rectifier step-down switching regulator, a hysteresis comparator compares the detection voltage that corresponds to the output voltage of the step-down switching regulator with a first threshold voltage and a second threshold voltage. A light-load detection circuit detects whether or not a load is in the light-load state. A driver circuit turns on / off the switching device elements according to the pulse signal output from the hysteresis comparator. Upon the light-load detection circuit detecting the light-load state, the hysteresis comparator shifts the second threshold voltage toward the higher-voltage side by a predetermined voltage difference.

A solid-state image capture device includes: at least one photoelectric converter provided at an image capture surface of a substrate to receive incident light at a light-receiving surface of the photoelectric converter and photoelectrically convert the incident light to thereby generate signal charge; at least one on-chip lens provided at the image capture surface of the substrate and above the light-receiving surface of the photoelectric converter to focus the incident light onto the light-receiving surface; and an antireflection layer provided on an upper surface of the on-chip lens at the image capture surface of the substrate. The antireflection layer contains a binder resin having a lower refractive index than the on-chip lens and low-refractive-index particles having a lower refractive index than the binder resin.

A method of driving a gate line includes: charging one of a scan start signal and a carry signal provided from a previous stage to a first node of a present stage; outputting a gate signal through a gate node of the present stage by pulling up a high level of a first clock signal at the first node to boost up a voltage potential of the first node; discharging the voltage potential of the first node and a voltage potential of the gate node to hold the first node and the gate node at a first power voltage as the first clock signal is shifted to a low level; and receiving a voltage potential signal of a second node of the previous stage, the second node holding a gate signal outputted from the previous stage, to reduce a ripple generated at the first node.

System and methods for wireless energy and data transmission are described. One aspect includes an emitter and receiver. The emitter may include primary and secondary emitting windings. The receiver may include primary and secondary receiver windings. In further aspects, the emitter may include a tertiary emitting winding and the receiver may include a tertiary receiver winding. In one aspect, the emitter uses driving circuitry and the receiver uses rectifying circuitry and one or more capacitors. In further aspects, the emitter and receiver are reversible.

According to input parameters, a controller carries out: generation of a voltage command value for each of d- and q-axes; conversion of the voltage command value for each of the d- and q-axes into a voltage command value for each of the multiphase windings; and control of a multiphase inverter based on the voltage command value for each of the multiphase windings. The controller adds, to the voltage command value for the q-axis, a first compensation voltage value for compensating torque ripples to thereby output a compensated voltage command value for the q-axis. The first compensation voltage value contains m-th harmonic components in the AC motor and varies depending on the rotational angle of the rotor, the m corresponding to the number of phase of the multiphase windings. The controller uses, as the voltage command value for the q-axis, the compensated voltage command value for the q-axis.

The present invention provides a ripple compensation method and apparatus that provides a means to compensate for drive current ripple-induced brightness fluctuations in an LEE based illumination system. The ripple compensation apparatus comprises a ripple evaluation module which is configured to evaluate a ripple compensation factor based on an evaluated fluctuation of the drive current. The evaluation of the fluctuation of the drive current can be determined based on information collected during operation of the LEE based illumination system and / or based on predetermined operational characteristics of the LEE based illumination. A control system comprises the ripple evaluation module and is operatively coupled to the one or more light-emitting elements, wherein the control system is configured to determine and provide control signals for operation of the one or more light-emitting elements based on the ripple compensation factor.

The system comprises a first motor for applying rotational energy to a respective first wheel of the vehicle. A second motor is arranged for applying rotational energy to a respective second wheel of the vehicle. A first inverter is coupled to the first motor, where the first inverter is capable of receiving direct current electrical energy from the direct current bus. The first inverter is configured to provide a first group of alternating currents with a corresponding reference phase. A second inverter is coupled to the second motor. The second inverter is capable of receiving direct current electrical energy from the direct current bus. The second inverter is configured to provide a second group of alternating currents with a phase shift with respect to the reference phase, such that the phase shift is effective to reduce the direct current ripple on the direct current bus.

A power control circuit is provided containing a switch array, which includes segmented switches, a flying capacitor, an output voltage terminal, a feedback loop, and a digital voltage regulator block. The digital voltage regulator block includes an A / D converter, an encoder, an add-subtractor, and a gate logic. These power control circuits do not include pass transistors. A method is also provided, where the charge pumps of the power control circuit are operated in two-phase cycles including a charging phase and a pumping phase. The power control circuit is controlled in both of these phases, thereby reducing the ripple of the output voltage.

In an inverter apparatus, an output voltage of an active filter circuit that steps up and smoothes a DC voltage is converted into an AC voltage by an inverter circuit. The active filter circuit includes a capacitor and a rectifier device connected between an input node and an output node. An inductor, one end of which is connected to the input node and the other end of which is connected the output node through the rectifier device, and a switch device connected between the other end and a low-potential-side line, and a first control circuit for the switch device are provided. The inductor stores energy while the switch device is on and releases the energy while the switch device is off. The rectifier device conducts such that the stored energy of the inductor is released.

In a switching regulator, when a control switching signal received from outside is indicating PWM control, a second reference voltage generating circuit outputs, as a second reference voltage, a voltage that is lower than the minimum voltage of an output voltage range of an error amplifying circuit, so that output signals from a comparator are fixed at a high level. When a control switching signal received from outside is indicating VFM control, the second reference voltage generating circuit adjusts the second reference voltage according to the voltage difference between an input voltage and an output voltage, because the optimum second reference voltage varies according to the voltage difference between the input voltage and the output voltage.

The objective of this invention is to reduce the current flowing through the inductance element in a step-up / step-down DC-DC converter and to control the ripple in the output voltage. In the DC-DC converter, four states, that is, the first state [1] of (M1, M2)=(off, on) and (M3, M4)=(on, off), the second state [2] of (M1, M2)=(on, off) and (M3, M4)=(off, on), the third state [3] of (M1, M2)=(on, off) and (M3, M4)=(on, off), and the fourth state [4] of (M1, M2)=(off, on) and (M3, M4)=(off, on) are repeated in a prescribed order, preferably in the order . . . [1]→[4]→[2]→[3]→[1] . . . or . . . [1]→[3]→[2]→[4]→[1] . . . .