33results about How to "Reduce voltage ripple" patented technology

Method and device for providing voltage generation with load-based control are disclosed. The voltage generation can be provided within an electronic device, such as a memory system that provides data storage. In one embodiment, an electrical load imposed on a generated voltage can be monitored and used to dynamically control strength of the generated voltage. For example, for greater electrical loads, the generated voltage can be provided with a greater strength, and for lesser electrical loads, the generated voltage can be provided with a lesser strength. By compensating the generated voltage for the nature of the imposed electrical load, the generated voltage can be provided in a stable manner across a significant range of loads. In the case of a memory system, stability in the generated voltage provides for reduced voltage ripple and thus improved sensing margins. The voltage generation is well suited for use in portable memory products (e.g., memory cards) to generate one or more internal voltages.

The invention discloses an energy control method of a laser wireless power transmission system based on the efficiency optimization, and belongs to the technical field of laser wireless power transmission. An energy control strategy is mainly composed of an efficiency optimized control strategy and an energy management optimization strategy. In the efficiency optimized control strategy, under the premise that the output power of a photovoltaic array meets the load and storage battery power requirements, an efficiency optimized operating point of the system is searched by gradually reducing the pulse width of an input pulse current of a laser. In the energy management optimization strategy, the system efficiency and system charging power are taken as control objectives, the pulse width of an input current of the laser is further reduced to search for an optimum operating point of the system, the average output power of the laser is properly reduced in the searching process of the optimum operating point of the system to maintain the output voltage ripple of the photovoltaic array within a limited range thereof, the impact of excessive voltage ripple on the efficiency of the photovoltaic array is avoided, the rapid storage battery charging needs are thus met and meanwhile the system is allowed to operate at the efficiency optimized point.

A low noise multiphase charge pump comprises a plurality of capacitors and a plurality of switches configured as a network, the switches are so switched that the charge pump operates in at least three phases by turns, and the operational durations and the operational currents of the phases are preferably balanced, so as to reduce the noise of the charge pump.

The invention discloses an integrated multifunctional power source switching system. An alternating-current interface of the integrated multifunctional power source switching system is connected with an alternating-current end switch through an EMI filter, passes through the alternating-current end switch, a first direct-current end inductor and a second direct-current end inductor and is connected with bridge arm middle points formed by a first power switch device, a second power switch device, a third power switch device and a fourth power switch device respectively; the positive electrode and the negative electrode of a first direct-current end interface are connected with the positive electrode and the negative electrode of a first direct-current end filter capacitor respectively, the positive electrode of the first direct-current end filter capacitor passes through a direct-current end switch and then is divided into two paths, and the two paths pass through the first direct-current end inductor and the second direct-current end inductor and then are connected to bridge arm middle points formed by the first power switch device, the second power switch device, the third power switch device and the fourth power switch device respectively. The switching system is used for mutual switching between alternating currents and direct currents of an electric automobile power source system, and two-way direct current-direct current switching, single-phase alternating current-direct current switching and direct current-single-phase alternating current switching between power sources are achieved.

The invention relates to a light emitting diode driving method, suitable for driving a plurality of light emitting diode strings. Each light emitting diode string comprises a light emitting diode or a plurality of light emitting diodes connected in series. The light emitting diode driving method comprises the following steps of: acquiring the initial duty ratio of the driving current of each light emitting diode string in a frequency cycle so as to acquire the target accumulated glow brightness of each light emitting diode string; when the maximum value of the initial duty ratios of the driving currents of the light emitting diode strings in the frequency cycle is smaller than the frequency cycle, extending the duty cycle of the driving current of each light emitting diode string in the frequency cycle and enabling the accumulated brightness of the light emitting diode string in the extended duty cycle to be equal to the target accumulated glow brightness.

A light-emitting diode (LED) lighting system comprising a luminaire and an LED luminaire control gear is used to replace the luminaire operated with alternate-current (AC) mains. The luminaire coupled to the LED luminaire control gear comprises LED arrays and a power supply. The LED luminaire control gear comprises a rechargeable battery, a current-fed inverter, and a relay switch. When a line voltage from the AC mains is unavailable, the LED luminaire control gear is automatically started to provide a high output voltage within an input operating voltage range of the luminaire and a low direct-current (DC) voltage to control the power supply to provide an LED driving voltage greater than a forward voltage across the LED arrays, eliminating operating instability of the power supply. The relay switch is configured to couple either the line voltage or the high output voltage to the power supply to operate thereon.

A multiphase magnetic integration coupling inductor comprises a U-type iron core, a T-type iron core and coils; the magnetic pillars of the T-type iron core are positioned between magnetic pillars of the U-type iron core; an air gap group is formed between the magnetic yoke of the T-type iron core and each magnetic pillar of the U-type iron core; another air gap group is formed between the magnetic yoke of the U-type iron core and each magnetic pillar of the T-type iron core; each magnetic pillar of the U-type iron core are winded by the coil. The advantages are that the multiphase magnetic integration coupling inductor is applied to coupling integration of each phase inductor in an interleaving switch power supply, thus improving symmetry level of each phase inductance parameters, simplifying iron core coupling structure, reducing coil length, saving copper material, reducing coil copper loss, reducing power supply output current and voltage ripples, reducing power supply output filter capacitance, and improving power supply efficiency and dynamic response speed .

The present invention relates to a motor driving apparatus and, more specifically, to a motor driving apparatus for selectively performing identical phase overmodulation compensation or minimum distance overmodulation compensation according to a command speed when an output voltage command value of an inverter indicates an overmodulation voltage.

In one example, a circuit includes an alternating current (AC) voltage source, a voltage rail, a reference rail, a first capacitor, a second capacitor, and a switching unit. The AC voltage source is configured to supply voltage in a first direction during a first half of a cycle and supply voltage in a second direction during a second half of the cycle. During a first state of the circuit, the voltage in the first direction supplied by the AC voltage source charges the first capacitor and the voltage in the second direction supplied by the AC voltage source charges the first capacitor. During a second state of the circuit, the voltage in the first direction supplied by the AC voltage source charges the first capacitor and the voltage in the second direction supplied by the AC voltage source charges the second capacitor.

The present invention relates to a DC-DC boost converter for photovoltaic applications, where the DC-DC converter comprises an input terminal (14), and an output terminal (6) and a first autotransformer (37) comprising an intermediate terminal (15) and first and second end terminals (16, 17), a first diode (19), one terminal of which is coupled to said first end terminal (16), a second diode (20), one terminal of which is coupled to said second end terminal (17); where the second terminals of said diodes are connected to said output terminal (6); and where the output terminal (6) is coupled to said common terminal (8) of the converter through a first capacitor (10). In the converter according to the invention the first and second end terminals (16, 17) of the first autotransformer (37) are respectively connected to first and third terminals (55, 59) of a three-state switching cell (21), and second and fourth terminals (56, 60) of the three-state switching cell (21) are connected to the common terminal (8) of the converter. Preferably, the converter of the invention is provided with a snubber circuit (36, 18) between the input terminal and the output terminal of the converter in order to minimize the recovery current of boost diodes added to the three-state switching cell.

An aircraft power supply for providing DC power with improved power quality characteristics to the aircraft. According to one embodiment, the aircraft power supply includes an input filter, a step-down transformer, one or more rectifier networks, and an output filter with a voltage modulation attenuator to passively improve power quality characteristics. The voltage modulation attenuator may use a certain arrangement of inductors, capacitors and diodes to reduce voltage transients in the aircraft power supply.

The invention discloses a multi-output switched capacitor converter applicable for multi-layer stacked loads. The multi-output switched capacitor converter comprises a first drive signal input end, asecond drive signal input end, N inner fly capacitors, N output capacitors, 2N branches and N interlayer loads, wherein the 2i-th branch, the (2i-1)-th branch, the i-th inner fly capacitor and the i-th output capacitor form a i-th power supply module; and the power supply modules are stacked in sequence. The multi-output switched capacitor converter is relatively low in voltage ripple and relatively high in conversion efficiency.

The invention discloses a single 24-pulse dry traction rectifier transformer with double-bridge windings arranged in a mirroring manner. The double-bridge winding adopts an axial double-split double-bridge four-winding structure, and each phase winding is nested on three conjugate iron cores which are sequentially arranged at intervals; the windings comprise three sets of primary side upper bridgewindings, three sets of primary side lower bridge windings, three sets of secondary side upper bridge triangular windings, three sets of secondary side lower bridge star-shaped windings, three sets of secondary side upper bridge extension windings, three sets of secondary side lower bridge extension windings, three sets of secondary side upper bridge common side windings and three sets of secondary side lower bridge common side windings. The size of the transformer is remarkably reduced, the manufacturing cost of the transformer is reduced, the transformer manufacturing process is simplified,and the electric energy quality of a rectifier system is improved. The short circuit impedance of the primary side single-phase winding to each set of secondary side single-phase winding can be completely consistent, and the short circuit impedance of the primary side three-phase winding to each set of secondary side three-phase winding can be completely consistent, so that the circulating current between the secondary side windings of the transformer is effectively reduced, and the local winding overheating phenomenon of the secondary side windings is prevented.

The invention discloses a voltage generator suitable for flash memories. The voltage generator comprises a charge pump circuit and a voltage regulator. The charge pump circuit comprises at least one charge pump unit, and each charge pump unit is provided with a voltage receiving end and a voltage transferring end. The voltage receiving ends receive reference voltage, and the voltage transferring ends generate output voltage. Each charge pump unit comprises a first voltage transferring channel, a second voltage transferring channel, a first capacitor and a second capacitor. The first voltage transferring channels and the second voltage transferring channels are respectively controlled by first control signals and second control signals for breakover or turn-off. The first capacitors and the second capacitors respectively receive first pumping enable signals and second pumping enable signals. The voltage regulator receives and generates regulated output voltage according to the output voltage.

The invention relates to the technical field of converters, and discloses a three-level circuit voltage ripple control method and device, and electronic equipment. The method comprises the following steps: detecting whether an inductive current flowing through an inductor in a three-level circuit needs to be adjusted or not; when it is detected that reduction is needed, if the circuit is in a boost or buck-boost mode, a second time period is inserted in a first time period in which each power unit runs in a first state, and the power unit is switched to run in a second state in the second time period; if the power unit is in the boost mode, the inductive current drops when the power unit operates in the first state; when the power unit needs to be boosted, if the circuit is in a voltage reduction or voltage boosting and reducing mode, inserting a third time period in the first time period, and switching the power unit to a third state for operation in the third time period; wherein, if the circuit is in the step-down mode, the inductive current rises when the power unit operates in the first state. The inductive current can quickly track the load current, so that the output voltage ripple of the three-level circuit is reduced.

A system including a variable frequency generator (VFG) including a generator configured to conduct alternating current to a first rectifier configured to convert alternating current from the VFG to direct current and drive it to an HVDC Bus Network, a variable frequency second generator including a second generator configured to conduct alternating current to a second rectifier configured to convert alternating current from the second generator to direct current and conduct it to the HVDC Bus Network, a speed correcting gearbox operatively connected to the VFG configured to align generator frequency to the second generator frequency, and a VFG control unit operatively connected to the generator configured to control the VFG, and a second generator control unit operatively connected to the second generator and the HVDC Bus Network configured to control the second generator.