237results about How to "Reduced turn-off loss" patented technology

The invention discloses a control method and a control circuit of an isolated bidirectional charger, belonging to the technical field of power electronic converters. The bi-directional charger controlcircuit adopted by the method comprises a bi-directional AC/DC converter, an isolated DC/DC converter and a control unit. The power grid is connected to the battery pack through bi-directional AC/DCconverter, isolated DC/DC converter, isolated DC/DC converter using LLC converter, control unit including sampling circuit, DSP and optocoupler isolated driving circuit. The control method realizes the high efficiency of bi-directional operation and forward and backward operation of the vehicle-mounted charger, and has the advantages of high power density, high reliability, few devices and high efficiency.

The invention provides a three-level inverter and a piece of power supply equipment. The three-level inverter comprises a first IGBT (insulated gate bipolar transistor), a second IGBT, a third IGBT, a fourth IGBT, a first clamping diode and a second clamping diode, wherein the collector electrode of the first IGBT is connected to a positive direct current bus, the emitting electrode of the first IGBT is connected to a first connection point, and a first fly-wheel diode is bridged between the collector electrode and the emitting electrode; the collector electrode of the second IGBT is connected to the first connection point, the emitting diode of the second IGBT is connected to a second connection point, and a second fly-wheel diode is bridged between the collector electrode and the emitting electrode of the second IGBT; the collector electrode of the third IGBT is connected to the second connection point, the emitting electrode of the third IGBT is connected to a third connection point, and a third fly-wheel diode is bridged between the collector electrode and the emitting electrode; the collector electrode of the fourth IGBT is connected to the third connection point, the emitting electrode of the fourth IGBT is connected to a negative direct current bus, and a fourth fly-wheel diode is bridged between the collector electrode and the emitting electrode; and the turning-on/off speeds of the first IGBT and the fourth IGBT are higher than the turning-on/off speeds of the second IGBT and the third IGBT, so that the conversion efficiency of the inverter is improved.

The invention provides a silicon carbide MOSFET device and a manufacturing method thereof. Silicon carbide deep P injection is performed in a specified region, groove etching and deposition of metal or polysilicon are performed above a silicon carbide deep P doped region, and the deposited metal or polysilicon is in direct contact with the silicon carbide N-epitaxy to form a Schottky contact or aSi/SiC heterojunction contact having rectifying characteristics. Therefore, the integration of multiple sub-rectifiers is achieve while optimizing the basic performance of the conventional silicon carbide UMOSFET, the working performance of the third quadrant of the device is greatly optimized, the gate-drain capacitance of the device is reduced and the switching speed of the device is improved.

The present invention discloses a switch power source of an inverse-excitation type self-excitation converting circuit which comprises an input rectification wave filtering circuit which is connected with an alternating current source. The input rectification wave filtering circuit is connected with a switch adjusting tube and a transformer. The transformer is connected with an output rectification wave filtering circuit. The switch adjusting tube is connected with a switch state controller. A switching tube clamp absorbing circuit is connected between the switch adjusting tube and the transformer. A switching tube acceleration switching circuit and a feedback forming circuit of the voltage stabilizing control signal are connected between the switch state controller and the transformer. The switching frequency of the switch power source according to the invention is unlike to the conventional switch power source and will not ascend to a high value in light load. The switching frequency will not keep to ascent when the load is reduced to a certain degree and an intermittent operation mode is switched to. The main switch frequency is fundamentally sustained to the frequency before the transition point. The switch power source has the advantages of reduced switching loss, increased efficiency of the electric power source, improved working condition of the switch adjusting tube and increased reliability of the electric power source.

The invention provides a silicon carbide MOSFET device and a manufacturing method thereof. The invention improves device structure design and finally integrates Schottky contact or heterojunction contact with rectifying characteristics on the basis of traditional silicon carbide UMOSFET structure. At that same time of optimize the basic characteristics of the traditional silicon carbide UMOSFET structure, the improvement realize the integration of multi-sub rectifier devices, greatly optimizes the work performance of the third quadrant of the device, and in addition, the invention also optimizes the dynamic performance of the device, and has shorter switching time; In addition, the invention also has the characteristics of simple process and easy realization.

The invention discloses a modulation method of a three-phase isolation type bidirectional direct-current converter under double PWM (pulse width modulation). The modulation method includes steps of 1) determining seven switch modes by adopting a PWM strategy according to the conditions that phase shift angle and duty ratio of corresponding drive signals on two sides of a three-phase transformer change to generate different voltage and current waveforms on two sides of the transformer; 2) calculating soft switching ranges corresponding to the switch modes; 3) calculating minimum current peak flowing through the three-phase transformer within the soft switching range of each switch mode; 4) comparing calculation results to obtain the situation that the current peak flowing through the three-phase transformer is minimum on the premise of soft switching within the integral power range; 5) giving output power and voltage transmission ratio and determining the switch modes and corresponding the duty ratio and the phase shift angle by judging the range where the output power and the voltage transmission ratio belong to. On the basis of soft switching, the current peak is minimum, switch loss of switching devices is reduced and efficiency of the converter is improved.

The invention provides an AC/DC resonant converter. A power conversion circuit is composed of basic switch units and a resonant tank, a controller adaptively controls the power conversion circuit according to different AC input voltages or different DC output voltages and switches the power conversion circuit into one or more basic switch units which are connected in series and in parallel and stacked to work and work in a high-frequency full-voltage control mode when alternating current input low voltage or direct current output high voltage exists, otherwise, work in a low-frequency partial-voltage control mode when alternating current inputs high voltage or direct current outputs low voltage, the two two-level control modes share the same set of resonant devices to simplify the design of a resonant tank, the controller is internally provided with a multiplier function unit, and the AC input current tracks the frequency and phase of the input voltage in real time so as to realize a power factor correction function. The AC/DC resonant converter directly converts the AC input instantaneous voltage into the DC output voltage, so that a conventional PFC converter and a DC bus capacitor thereof can be saved, the conversion efficiency is improved, and the component cost is reduced.

Disclosed is a semiconductor device. The semiconductor device comprises at least one cell, and the structure of any cell comprises an N-type substrate, at least one N-type carrier barrier region, andat least one P-type electric field shielding region, wherein at least one first groove unit and at least one second groove unit are included on one side of the N-type substrate; at least one P-type semiconductor region is arranged on the other side of the N-type substrate, wherein the P-type semiconductor region is referred to as an anode region. The invention aims to provide the semiconductor device, wherein the semiconductor device has a novel cellular structure so as to obtain a large safe operating area, and the anti-short-circuit capability; the effect of a parasitic thyristor is eliminated; the low-grid-collector charges (QGC) are adopted to obtain the maximum anti-dv/dt capability; the emitter side electric conduction modulation is added, so that a relatively large current density and an extremely low conducting voltage drop can be obtained; and relatively turn-off loss and relatively low process complexity are achieved.

The invention belongs to the technical field of power semiconductors, and particularly relates to a self-adaptive SOI LIGBT device. Compared with a traditional structure, the self-adaptive NMOS structure is introduced into the collector electrode end, and a Zener diode structure is introduced into the emitter electrode end. During forward conduction, the NMOS channel at the collector end is closed, an electron extraction path at the collector end is blocked to eliminate the voltage turn-back effect, and at the moment, the Zener diode is reversely biased but is not broken down, and holes storedin the drift region cannot be extracted, so that the new device can obtain low forward conduction voltage drop. In the turn-off process, along with rise of collector voltage, the collector NMOS channel is adaptively opened to form the electron extraction path, the Zener diode is reversely broken down and conducted to extract an emitter end hole, and the NMOS channel and the Zener diode accelerateturn off of the device to reduce the turn-off loss; and in a short-circuit state, the Zener diode is reversely broken down and conducted, so that the saturation current density can be reduced to improve the short-circuit resistance. Therefore, the device has smaller conduction voltage drop and turn-off loss, and a wider safety working area.

The invention discloses an isolation driver and a high frequency switching power supply. The isolation driver comprises a power amplification circuit module, an isolation coupling transformer, an upper switch tube drive circuit module and a lower switch tube drive circuit module. The upper switch tube drive circuit module and the lower switch tube drive circuit module respectively comprise a negative voltage auxiliary power sub module and a Miller clamp circuit sub module, wherein the negative voltage auxiliary power sub module is used for providing an off-drive auxiliary power supply for theMiller clamp circuit sub module, and the Miller clamp circuit sub module is used for clamping a driving signal output to a switch tube gate to the negative voltage when the isolated coupled driving signal voltage is not positive. Miller clamp circuits are adopted to clamp the driving signal of the negative voltage to reduce the effect of a Miller capacity on the drive, reduce the off consumption and improve the working reliability.

The invention discloses an IGBT device drive circuit and method capable of reducing the turn-off loss. The circuit comprises a detection module, a current drive module, a comparison module and a logic control module, wherein an input end of the logic control module is used for connecting external pulse width modulation signal and digital bit selection signal; a feedback end of the logic control module is connected with an output end of the comparison module; the input end of the current drive module is connected with the output end of the logic control module; the output end of the current drive module is used for being connected to a control end of an IGBT device; the input end of the detection module is used for being connected with the output end of the IGBT device; and the output end of the detection module is connected to the input end of the comparison module. According to the IGBT device drive circuit and method, the turn-off power loss of the IGBT device can be reduced; the device is prevented from being burnt by current and voltage overshoots caused by turn-off; meanwhile, output voltage and current of the drive circuit can be accurately controlled; the turn-off speed is increased while the turn-off overshoot voltage of the IGBT is not increased; the signal delay is relatively small; and the condition that a feedback circuit of the drive module normally works within short turn-off time of the IGBT device can be ensured.

The invention provides a cascade full-bridge direct-current breaker. The cascade full-bridge direct-current breaker comprises a main through-flow branched circuit, a transfer branched circuit and an energy absorption branched circuit which are in parallel; the main through-flow branched circuit comprises a first full-bridge module and a mechanical switch which are connected in series; the transfer branched circuit comprises N second full-bridge modules which are connected in series successively; the energy absorption branched circuit comprises M lightning arresters; and the full-bridge modules adopt bridge-arm circuits or diode bridge-arm circuits composed of full-control devices. Through the technical scheme provided in the invention, nonlinear resistance voltage sharing is adopted, the constitution form is greatly simplified, and the total cost and volume of the equipment are reduced; compact arrangement of the cascade full-bridge direct-current breaker is facilitated, the stray parameter is easily reduced, overvoltage inhibition is realized, the overall application reliability is improved, high-speed reclosing of the cascade full-bridge direct-current breaker in several milliseconds can be realized, the application range of the cascade full-bridge direct-current breaker is expanded, and the operation reliability and economical efficiency of a flexible multi-port and direct-current power grid are further improved.

A current enhanced type lateral insulated gate bipolar transistor improves current density and the turn-off speed on the premise that a latching ability is maintained to be unchanged. The semiconductor is provided with buried oxide disposed on a P-type substrate and an N-drift region disposed on the buried oxide, a P-body region and an N-buffer region are disposed on the N-drift region, a P-type collecting electrode region is disposed in the N-buffer region, an anode metal is connected to the P-type collecting electrode region, a field oxide layer is disposed on the N-drift region, a P-well region is disposed in the P-body region, a P-type emitting electrode region and an emitting electrode region are disposed in the P-well region, the inner-side boundaries of the four regions, i.e., the P-body region, the P-well region, the P-type emitting electrode region and the emitting electrode region are synchronously recessed inwardly to form a square groove, the emitting electrode region surrounding the groove is successively defined as a first P-type emitting electrode region, second, third and fourth N-type emitting electrode regions and a fifth P-type emitting electrode region, the N-drift region protrudes outwardly and fills the square groove, a surface of the P-body region is provided with a gate oxide layer, a surface of the gate oxide layer is provided with a polysilicon layer, and a gate metal is connected to the polysilicon layer.

The invention provides a fixed-frequency control method of a full-bridge LLC resonant converter. The full-bridge LLC resonant converter is composed of a direct-current input source Vin, a primary sidesquare-wave generator I, a primary side LLC resonant circuit II, a transformer III, a secondary side full-bridge rectifying circuit IV, an output filter capacitor Co and an output resistance load Ro.The primary side square wave generator I is composed of a primary side first switch tube S1, a primary side second switch tube S2, a primary side third switch tube S3 and a primary side fourth switchtube S4. The primary side LLC resonance circuit II is composed of a resonance capacitor Cr, a resonance inductor Lr and an excitation inductor Lm. The primary side second switch tube S2 and the primary side fourth switch tube S4 are controlled through a pair of fixed-frequency complementary pulses, a duty ratio is 50%, and a switch frequency is equal to a series resonant frequency of the resonantcapacitor Cr and the resonant inductor Lr. Switch pulses of the primary side first switch tube S1 and the primary side third switch tube S3 are controlled through output voltage feedback, and duty ratios of the switch pulses of the primary side first switch tube S1 and the primary side third switch tube S3 are complementary.

The present invention discloses a high-frequency auxiliary converter for a D-series high-speed train and a control method thereof. The auxiliary converter comprises a tandem type DC / DC chopper circuit, high-frequency transformers TR 1 and TR 2, a tandem type rectification circuit, a resonance circuit and a three-phase inverter circuit. The tandem type DC / DC chopper circuit is connected with primary sides of the high-frequency transformers TR 1 and TR 2, and secondary sides of the high-frequency transformers TR 1 and TR 2 are connected with the three-phase inverter circuit through the tandem type rectification circuit and the resonance circuit in sequence; In order to realize zero current switching off of a chopping IGBT, the control mode of switching off drive pulse of the chopping IGBT and drive pulse of a resonance IGBT at the same moment is adopted, the chopping IGBT pulse width is adjusted by cascade stability control algorithm, and the resonance IGBT pulse width is a fixed value. According to design of the corresponding topological structure and the control method, a traditional power frequency converter can be directly omitted, system weight and volume are reduced, working frequency and efficiency of an auxiliary system are guaranteed, and high practical value is achieved.

The invention relates to a voltage rise circuit, which uses direct current chopper voltage rise circuit. It is characterized in that: said direct current chopper voltage rise circuit is formed by at least two direct current chopper voltage rise return circuits, while they are parallel connected by sharing capacity, and via dislocation compensation to improve the switch frequency. The invention can arrange at least one direct current chopper voltage rise return circuit with shared capacitor parallel with the common chopper voltage rise return circuit and via the dislocation compensation of parallel return circuits to improve the switch frequency.

The invention discloses an SOI LIGBT device with a diode clamping carrier storage layer. A P type semiconductor base region is partitioned into a plurality of areas, and two or three series diodes areintroduced in different areas, so that, during reverse voltage resistance of the device, after the potential of a P type electric field shielding region is elevated to the drop voltage of the two orthree diodes, the diodes are turned on, the potential of the P type electric field shielding region is clamped near the drop voltage of the two or three diodes, the potential of an N type carrier storage area is preferably shielded by the P type electric field shielding region to an extremely low value, and the voltage resistance of the device is used for bearing a reverse diode mainly composed ofa P type electric field shielding region and a surface voltage resistance region, so that the contradictory relation between breakdown voltage and the concentration of an N type carrier layer is broken thoroughly.

The invention belongs to the technical field of power semiconductors and particularly relates to a high-speed and low-loss multi-trench gate high-voltage power device. Compared with a traditional structure, the structure of the high-speed and low-loss multi-trench gate high-voltage power device has the advantage that a plurality of trench gate structures are introduced into an emitter terminal anda collector terminal. Channels in side walls of trench gates at the collector terminal are turned off and a connection path of an N+ collector region and an N-type buffer layer is blocked during forward conduction, so that the voltage foldback effect can be eliminated. A trench gate structure at the emitter terminal can increase the channel density to reduce the resistance of a channel region, and a barrier trench gate and a carrier storage layer can effectively improve the carrier concentration of a drift region, so that the novel device can obtain lower forward conduction voltage drop. In the turn-off process, the channels in the side walls of the trench gates at the collector terminal are opened along with voltage rise of a collector, so that the N+ collector region communicates with the N-type buffer layer to form a rapid electron extraction path and turn-off of the device is accelerated to reduce the turn-off loss. Therefore, the high-speed and low-loss multi-trench gate high-voltage power device has lower forward conduction voltage drop and smaller turn-off loss and does not have the voltage foldback effect.