46results about How to "Reduce the maximum voltage" patented technology

DC-DC converters adapted to provide two or more DC output voltages. More particularly, a multi-state or mode DC-DC converter circuit comprising first and second controllable switches configured for unidirectional conduction of charging current.

The present invention relates to a coil arrangement, in particular for use in a magnetic particle imaging apparatus (100), comprising a coil split into at least two coil segments, wherein the winding direction is inverted between at least one coil segment to another coil segment, and a capacitor coupled between at least two adjacent coil segments. Further, the present invention relates to such a magnetic particle imaging apparatus, in particular an apparatus (100) for influencing and/or detecting magnetic particles in a field of view (28), which apparatus comprises selection means and drive means (120) wherein at least one drive field coil and/or at least one selection field coil representing a selection field element is implemented by a coil arrangement as proposed according to the present invention.

A light-emitting element driving device includes: a plurality of light emitters; a power supply; a plurality of current control transistors; a plurality of constant-current circuits; a voltage selecting circuit; a control circuit; and a voltage controller.

The invention discloses an axial double-split dry-type transformer coil structure with the same connection groups and a winding method. The axial double-split dry-type transformer coil structure comprises a first low-voltage coil, a second low-voltage coil and a group of high-voltage coils, wherein each of the first low-voltage coil and the second low-voltage coil is provided with two low-voltage coil sections, the two low-voltage coil sections of the first low-voltage coil and the two low-voltage coil sections of the second low-voltage coil are distributed in a cross mode, and two sections of leads for winding forming of the first low-voltage coil and the second low-voltage coil are leaded in and out from the upper end and the lower end respectively. The high-voltage coils are provided with multiple high-voltage coil sections distributed in the axial direction, the high-voltage coil sections are sequentially and mutually connected in series, and leads for winding forming of the high-voltage coils are leaded in and out from the upper end and the lower end respectively. The axial height of the first low-voltage coil and the axial height of the second low-voltage coil are both consistent to the axial height of the high-voltage coils.

The present invention provides a semiconductor integrated circuit capable of achieving high voltage. The proposed semiconductor integrated circuit includes a first node [VOUT] connected to a first potential node [VDD], and a first n-channel transistor [NT1] and a second n-channel transistor [NT2] serially connected between a first node [VOUT] and a second potential node [VSS] of a lower potential than the first potential node. One end of NT1 is connected to the second potential node [VSS], the other end thereof is connected to one end of the second n-channel transistor [NT2], a gate terminal thereof is connected to a second node [VIN], the other end of NT2 is connected to the first node [VOUT], and a gate terminal thereof is connected to a first intermediate range potential [VM1] positioned between the first potential node [VDD] and the second potential node [VSS].

In displaying a predetermined image on a plasma display panel, occurrence of an initializing bright point can be suppressed to reduce the maximum voltage in an all-cell initializing operation, light emission in the all-cell initializing operation is suppressed to reduce the black luminance, and the contrast is sharpened. In driving the plasma display panel, one field period includes a plurality of subfields having a setup period for causing initializing discharge in discharge cells, an address period, and a sustain period. One field period includes at least one subfield for applying ramp waveform voltage increasing in the setup period to the scan electrodes. The maximum voltage of the ramp waveform voltage can be varied. When a predetermined image establishing a previously determined condition is displayed, the ramp waveform voltage is generated whose maximum voltage is smaller than when an image other than the predetermined image is displayed, and a positive voltage is applied to the data electrodes at least while the ramp waveform voltage having the smaller maximum voltage is applied to the scan electrodes.

The invention discloses a double-frequency circulating current injection method for suppressing capacitor voltage fluctuation of an MMC sub-module under a fault. The method comprises the steps: taking the fundamental frequency and double-frequency fluctuation components of capacitor voltage of the sub-module which generates an AC single-phase fault and considers double-frequency circulation injection as suppression targets, and building an optimization target function; carrying out global optimization by taking target function minimization as a target to obtain optimal amplitude and phase of double-frequency circulating current injection; and generating a reference signal according to the optimal amplitude and phase of the double-frequency circulating current injection, and realizing the double-frequency circulating current injection in combination with a modulation algorithm. According to the method, the capacitor voltage fluctuation of the sub-module during the fault period can be effectively reduced, and the maximum voltage borne by the MMC sub-module during the fault period is reduced.

The invention discloses a frequency-doubled circulation injection method for suppressing MMC bridge arm power fluctuation under a fault, and the method comprises the steps: taking a fundamental frequency and a frequency-doubled fluctuation component of bridge arm instantaneous power when an AC single-phase fault occurs as suppression targets, and building an optimization target function; carrying out global optimization by taking target function minimization as a target, and obtaining the optimal amplitude and phase of frequency-doubled circulation injection; and generating a reference signal according to the optimal amplitude and phase of the frequency-doubled circulation injection, and realizing the frequency-doubled circulation injection in combination with a modulation algorithm. According to the method, the capacitor voltage fluctuation of the sub-module during the fault period can be effectively reduced, and the maximum voltage borne by the MMC sub-module during the fault period is reduced.

The present disclosure is applied to touch technology, and provides an integrating circuit. The integrating circuit comprises an impedance unit, an amplifier, an integration capacitor, a discharge capacitor, a first switch and a second switch. The amplifier comprises a first input terminal, a second input terminal and an output terminal configured to output an output signal; the integration capacitor is coupled between the first input terminal and the output terminal; the first switch is coupled between the first input terminal of the amplifier and the second terminal of the discharge capacitor; and the second switch is coupled between the first terminal and the second terminal of the discharge capacitor.

The invention relates to a dry-type transformer used for an ozone generator, which comprises a casing, a high-tension coil and a low-tension coil. The high-tension coil and the low-tension coil are arranged inside the casing and are wound to enhance mechanical strength and reduce leakage inductance. An insulating cylinder is arranged between the high-tension coil and the low-tension coil, and an axial ventilation heat radiating hole is formed on the insulating cylinder. A shielding layer is arranged outside the casing to effectively reduce the influence of electromagnetic radiation on the surroundings. The inventive dry-type transformer has a large contact area between the high-tension/low-tension coil and the air, thereby having the advantages of good heat radiating and ventilation performance and strong overload capacity, having larger redundancy of coil temperature rise due to the limitation of load loss sometimes, and further improving the reliability of the transformer. Moreover, the dry-type transformer reduces the contaminating and damping extents of coils. With the improvement of the insulation treatment process of insulating materials and coils, the wearing and the noise are well controlled.

The invention discloses a dead zone compensation method and device based on asymmetric vector action time. The method comprises the following steps: calculating a dead zone equivalent time error according to inherent dead zone time of a driver, a switching state switching sequence, a current direction, a switching tube voltage drop and a diode voltage drop; and after the switching moment generatedby the dead zone effect is determined according to the current direction, adding the dead zone equivalent time error at the switching moment generated by the dead zone effect, and carrying out out dead zone compensation. The invention solves the problems that: in the prior art, only a dead zone of a system is compensated, but smooth transition during sector switching in the compensation process is not considered, the inverter generates the phenomenon that the two-phase switching state is changed at the same time, then the output level is subjected to non-unit mutation, therefore the action effect of dead zone compensation is affected, in addition, the maximum voltage and power loss borne by the power switch tube are increased, the device explosion is caused, and the like.

The invention discloses a stroboflash-free active power factor correcting circuit applied to LED drive. The stroboflash-free active power factor correcting circuit applied to LED drive comprises a rectifying circuit, a filtering capacitor, a first-level inductor, a control chip, a power tube, a transformer and an LED load circuit and is characterized by further comprising an energy storage capacitor, a first switch tube and a second switch tube, wherein one end of the first-level inductor is connected with the output end of the rectifying circuit, the other end of the first-level inductor is connected with the drain electrode of the power tube and the positive pole of the energy storage capacitor, the transformer comprises at least one main coil, one end of the main coil of the transformer is connected with the source electrode of the power tube through a sampling resistor, and the other end of the main coil of the transformer is in parallel connection with the negative pole of the energy storage capacitor. The stroboflash-free active power factor correcting circuit provides direct current constant source through the energy storage capacitor, two times of ripple waves of power frequency are eliminated, no stroboflash is output while power factor correction, the circuit is simplified, and cost is reduced.

The invention discloses a permanent-magnet speed-adjustable motor which comprises a motor base, wherein an outer rotor assembly and an inner rotor assembly are respectively arranged on the motor baseand at the two ends in the length direction of the motor base through bearings; the outer rotor assembly comprises a first rotating shaft, collecting rings are arranged on the first rotating shaft, abarrel-shaped iron core retainer is arranged at one end in the motor base of the first rotating shaft, an outer rotor iron core and a plurality of induction coils matched with the outer rotor iron cores are arranged in the iron core retainer, the output ends of the induction coils are connected with the collecting rings, the group number of the induction coils is 3N (the N is an integer), the group number of the induction coils is larger than or equal to 6, the number of the collecting rings is 3N, every three groups of induction coils can form a three-phase potential, and N three-phase potentials with the completely same phases can be achieved.

The invention discloses a mains supply fluctuation-resistant charging method, a charging terminal and a computer readable storage medium. The method comprises the following steps: dividing the charging process of a battery pack into a plurality of charging stages, and using different charging currents in each stage; and when the charging process is interrupted and recovered, reducing the range points of the plurality of charging orders to divide a new charging stage range, and after the charging stage of the current battery pack is re-judged, charging the battery pack by using the charging current corresponding to the charging stage. The problems that the battery cannot be fully charged and potential safety hazards exist due to overlarge charging current caused by the fact that the current charging stage is judged to be the previous charging stage because the judgment of the battery management system on the current charging current of the battery pack is influenced because the voltage of the battery pack is reduced after the charging process is interrupted are avoided.

The present invention discloses a low voltage DC-DC converter for a vehicle and a control method thereof. The low voltage DC-DC converter for a vehicle includes: a switching circuit including a plurality of capacitors and a plurality of switches and converting a high voltage output from a high voltage battery into an AC voltage; a transformer converting the AC voltage output from the switching circuit into a low voltage; a current sensor measuring a current value output from the transformer; and a controller comparing the current value measured by the current sensor with a reference value to determine whether a current mode is a continuous current mode or a discontinuous current mode, and controlling one of the plurality of switches to be turned on or off as the determination result.