33results about How to "Reduce capacitor size" patented technology

The invention relates to the field of power electronics, in particular to a multi-stage single switch boost converter which is composed of a Boost circuit and a plurality of Switch-Capacitor networks. Voltages supplied by all the Switch-Capacitor networks are equal. Accumulation of the network voltages is achieved in an interleaving series connection mode, an output voltage is boosted, and the capacity of boosting is high. The converter is provided with only one active switch element, a control circuit is simple, and voltage stress of a switching tube is small and 1/ (1-D) times that of an input voltage. Capacitor voltages of all the Switch-Capacitor networks are equal and 1/ (1-D) times that of the input voltage, stress of the capacitor voltages is small, therefore, the size of the circuit is reduced, and integration is easy.

The invention discloses a boost power factor correction (PFC) converter adopting a small-capacity long-service-life energy-storage capacitor. The boost PFC converter comprises a main power circuit and a control circuit, wherein the energy-storage capacitor in the main power circuit is the small-capacity long-service-life capacitor, and the control circuit comprises a differential sampling phase shift circuit, a rectifying circuit, a peak value sampling circuit, an adder and substracter circuit, an output voltage feedback control circuit, a multiplying unit, a PFC chip and a switching tube drive circuit. A simple harmonic current injection method is adopted to perform control and balancing of instant input power and output power, an energy-storage capacitor value can be decreased under the condition that the input power factor is ensured, the converter can use other types of capacitors, such as a thin-film capacitor or a ceramic capacitor and other small-capacity and long-service-life capacitors to replace an electrolytic capacitor, the obvious defect that a traditional electrolytic capacitor serving as the energy-storage capacitor is large in volume and short in service life and the like is overcome, and the boost PFC converter has the advantages that the power supply power density is remarkably improved, the service life is prolonged and the like.

The present invention discloses a full-wave active rectification LLC resonant converter and a control policy thereof, belonging to the technical field of power electronic converters. The input source,an input bus capacitor, a primary side switching network, a resonance inductor, a resonance capacitor, a transformer, n (>=1) secondary side full-wave active rectification switching networks, m (>=0)secondary side full-wave rectification switching networks, an output filtering capacitor and an output load; when an input voltage is close to a rated working point, a secondary side assistant activeswitch tube maintains closure, and a convertor employs frequency conversion control; when an input voltage drops, the duty ratio of the secondary side assistant active switch is regulated to maintainthe stable output voltage; and the full-wave active rectification LLC resonant converter can meet two demands of the power system for the steady-state working point efficiency and the transient voltage drop, and is specially suitable for application occasions where the power system is required to have a power-down maintenance capacity such as a server power source and a rail traffic power source.

The invention discloses a protective circuit for switching over-voltage protection of a dry air reactor, relates to an over-voltage protective circuit for the dry air reactor, and solves the following problems in the traditional reactor over-voltage protection: the capacitance volume is large and the production cost is high when a resistance-capacitance absorption circuit is singly used, and dispersibility of gap breakdown voltage is increased and service life of protective gap is reduced due to frequent actions of the protective gap when a gap protector is singly used. The protective circuit can be satisfied through choosing proper element parameters according to cut-off current; when the cut-off current is lower, a resistance-capacitance absorption device controls over-voltage amplitude values at two ends of the reactor to prevent the over-voltage amplitude values from reaching the breakdown voltage of the protective gap, the protective gap is in a disconnection state, and the reactor and respective resistance-capacitance elements form an RLC (Radio Link Control) oscillation circuit; when the cut-off current is higher, the over-voltage amplitude values at two ends of the reactor are higher, the protective gap is broken down, and a capacitor and a protective resistor thereof are short out; the protective circuit for the switching over-voltage protection of the dry air reactor is applied to the reactor protection field.

The invention discloses a large-capacity film capacitor, comprising an anode connecting terminal in connection with the anode of a power supply, an anode connecting polar plate welded with the anode of a capacitor core, a cathode connecting terminal in connection with the cathode of the power supply, capacitor cores, and a cathode connecting polar plate welded with the cathode of the capacitor core, wherein the large-capacity film capacitor further comprises a cathode connecting copper foil, an anode connecting copper foil, an anode-cathode insulation plate, a plurality of left polar plate copper foil spacers and a plurality of right polar plate copper foil spacers, and the capacitor cores are arranged in a square shape; the anode connecting copper foil passes through a plurality of the left polar plate copper foil spacers, the anode-cathode insulation plate and a corresponding space among four adjacent capacitor cores, respectively, and is welded integrally with the anode of the capacitor core; and the cathode connecting copper foil passes through a plurality of the right polar plate copper foil spacers, the anode-cathode insulation plate and a corresponding space among the four adjacent capacitor cores, respectively, and is integrally welded with the cathode of the capacitor core. The large-capacity film capacitor in the invention improves the capacitance of the capacitor, reduces the capacitive volume, and reduces the cost.

The invention relates to a foldable capacitor core. The foldable capacitor core comprises a double-sided metallized thin film; the double-sided metallized thin film comprises an insulating thin film;the two side surfaces of the insulating thin film are provided with a first metallized surface and a second metallized surface respectively; the double-sided metallized thin film is transversely and repeatedly folded to form a double-sided metallized thin film folding piece; a first terminal and a second terminal are arranged at the left end and the right end of the double-sided metalized thin film folding piece respectively; the first terminal is in conductive contact with the first metallized surface; and the second terminal is in conductive contact with the second metallized surface. According to the foldable capacitor core, the double-sided metallized thin film is transversely and repeatedly folded to form the capacitor core; and compared with a traditional thin film capacitor core formed by winding, one layer of isolating paper is omitted, so that the size can be reduced by more than 20%.

The invention provides a capacitor for connecting IGBTs in parallel and a manufacturing process and an application method thereof. The capacitor comprises a core injection molding assembly, a negativeelectrode copper bar, a positive electrode copper bar and a shell, wherein the core injection molding assembly includes an injection molding body and a plurality of capacitor film cores which are arranged in an array and penetrate through the injection molding body; the positive electrode copper bar and the negative electrode copper bar are not contacted; and the shell is formed by injection molding after the positive electrode copper bar and the negative electrode copper bar are connected to the core injection molding assembly. The manufacturing process comprises the steps of arranging a plurality of capacitor film cores in an array and then carrying out low-pressure injection molding to form an integrated core injection molding assembly; acquiring a positive electrode copper bar and a negative electrode copper bar by adopting stamping molding; welding the positive electrode copper bar and the negative electrode copper bar to the core injection molding assembly; placing the welded core injection molding assembly, the positive electrode copper bar and the negative electrode copper bar into an injection molding mold for fine positioning, and performing high-pressure injection molding; and compounding the positive and negative copper bars, the capacitor core and the plastic shell into a whole through the integrated injection molding process. The capacitor has the advantages of good shock resistance, good heat conductivity and small volume and mass.

The invention discloses an LED stroboscopic driving power supply of a novel rectification power rectification topology structure, and relates to the technical field of electronics and power. The LED stroboscopic driving power supply comprises an AC power supply, the AC power supply is connected with an EMI filter circuit, a rectification power correction circuit, an RCD buffer circuit, a flyback converter, an output filter circuit and an LED load successively, and an active capacitor circuit is connected in parallel between the rectification power correction circuit and the RCD buffer circuit.The rectification power correction circuit is of a brand new structure different from that of a diode rectification circuit or a bridge rectification circuit. The brand new power structure topologiccombination is used to improve the stability and reliability of the power supply and reduce power consumption and cost; an active capacitor is added after the rectification power correction circuit and before the RCD buffer circuit, the capacitance in the tail end of the rectification power correction circuit is greatly reduced, and requirement for high frequency switching in the primary side of the transformer can be met.

The invention discloses a three-dimensional stereo high-density film multi-layer capacitor. The capacitor comprises a substrate, an insulating film, a multi-layer capacitance function layer film, an insulating layer, an insulating passivation layer, a metal connecting layer, and a plate electrode. The insulating passivation layer covers the multi-layer capacitance function layer film. The plate electrode is connected to conductive plate films of the capacitor. The invention also discloses a preparation method of the above capacitor. The three-dimensional stereo high-density film multi-layer capacitor is manufactured through the steps of etching of the substrate, deposition of the insulating layer, deposition of the insulating passivation layer through a capacitance function layer, etc. The method is simple in process, and a multi-layer capacitance thin-film device can be formed without multiple times of lithography. The layers of films are not restricted. In an ideal condition, the layers of the capacitance function layer film can be freely set to be a finite number as long as the size of the capacitor is large enough, and the cost will not be increased substantially. Films can be adjusted to be distributed mostly in a vertical space, so the size of the capacitor can be greatly reduced. The capacitor is manufactured by a semiconductor film technology, is tolerant to environment, and exhibits high reliability.

The invention provides a front-end sampling circuit with a buffer. The front-end sampling circuit comprises a sampling module, a bootstrap switch, a driving module, a buffer module and a bias module; the driving module comprises a first connecting end and a second connecting end, and the sampling module comprises an input end, an output end and an offset end; the buffer module comprises an input end, an output end and a third connecting end; the first connecting end is connected with one end of the bootstrap switch, and the other end of the bootstrap switch is connected with the offset end of the sampling module; the input end of the buffer module is in butt joint with an input signal, and the output end of the buffer module is respectively connected with the second connecting end, one end of the bias module and the input end of the sampling module; the third connecting end is connected with the first connecting end; and the other end of the bias module is grounded. According to the invention, the linearity of the sampling network can be effectively improved.

The invention discloses a cascaded SVG system based on a double-BUCK module and a reactive power compensation control method so as to solve the problem that a control system is too complicated when aDC side voltage is stabilized and to improve the power density of a device. The system comprises a three-phase chain type SVG circuit and an inductor, one end of each of three phase links is connectedto a phase of A, B and C phases, the other end of each of the three phase links adopts a star connection manner, and each phase link of the three phase links comprises at least one double-BUCK sub-module connected in series. The double-BUCK sub-modules of the invention can control the system to cut off the communication with a DC side, a similar two-level control method can reduce a required sub-module capacitance, the power density is increased, and therefore, the problems of power density increase and DC failure suppression are solved.

The embodiment of the invention provides a display panel, a driving method thereof and a display device, relates to the technical field of display, and aims to improve the threshold voltage detection precision. The display panel includes a display area, the display area including a light emitting element and a pixel circuit connected to the light emitting element, the pixel circuit including: a driving transistor connected between a first fixed potential signal line and a first pole of the light emitting element; the data writing module is connected between a data line and the grid electrode of the driving transistor; the detection module is connected between the first pole of the light-emitting element and the detection signal line; a first pole plate of the storage capacitor is electrically connected with the grid electrode of the driving transistor; the charging control module comprises a first capacitor and a control unit, the first capacitor is connected between the second pole plate of the storage capacitor and the first pole of the light-emitting element, and the control unit is connected with the first pole plate of the first capacitor and the second pole plate of the first capacitor and used for controlling the first capacitor to be charged in the detection time period and not to be charged in the compensation time period.

The invention relates to an MMC-based high-frequency AC bus electric energy routing structure and a control strategy, and belongs to the technical field of electric energy conversion. The routing structure comprises a medium-voltage conversion stage, a high-frequency isolation stage and a low-voltage stage. The control strategy comprises medium-voltage conversion stage AC/DC conversion control, high-frequency isolation stage control and high-frequency AC bus low-voltage output end control. According to the invention, a modular multi-level converter is combined with an isolation transformer and a full-bridge structure to form a high-frequency AC bus electric energy routing structure and realize electric isolation, so that electric energy conversion links can be reduced, the capacitance volume of the modular multi-level converter is reduced, submodule voltage fluctuation suppression and automatic equalization are realized, the power density is improved, and system control is simplified.