47results about How to "Reduce reverse recovery loss" patented technology

An electric power conversion system includes a DC power supply, plural main circuit switching devices bridge-connected to carry out DC / AC convert, having freewheeling diodes connected in reverse parallel thereto, respectively, and a reverse voltage application circuit for applying a reverse voltage smaller than the DC power supply to each freewheeling diode, upon a cutoff of back-flow current of the freewheeling diode, the reverse voltage application circuit being composed of a series connection of a low-voltage DC power supply, a reverse voltage application switching device having a lower withstand voltage than the main circuit switching devices and adapted to turn on upon a reverse recovery of the freewheeling diode, and an auxiliary diode having a shorter reverse recovery time than the freewheeling diode, the reverse voltage application switch being a device having holes as a majority carrier.

The invention discloses a topological structure of a two-phase interleaved converter based on coupled inductors and belongs to the technical field of the power and electron technology. The two-phase interleaved converter based on the coupled inductors comprises a direct-current input source, two power switch tubes, the two coupled inductors with two windings, three one-way rectifier diodes, an output diode, a clamping capacitor, two intermediate energy-storage capacitors and an output filter capacitor. According to the two-phase interleaved converter based on the coupled inductors, the boosting capacity is high, output with a higher step-up ratio can be achieved, and stress of the peak voltage of the power switch tubes and stress of the peak voltage of the diodes are reduced to a certain extent; meanwhile, zero-current switching-on of the power switch tubes and turning-off the diodes are achieved through the leakage inductance of the coupled inductors, in this way, the conversion efficiency of a whole conversion circuit is improved, and input current ripples are reduced due to the adoption of a two-phase interleaved control method.

The invention belongs to the technical field of switching power supply control, and in particular relates to a switching power supply drive circuit for reducing the loss of MOS transistor body diodes in a switching power supply circuit. MOS tube drive power supply, lower MOS tube drive power supply, timing control circuit, upper MOS tube drive circuit and lower MOS tube drive circuit, the upper MOS tube drive circuit and / or the lower MOS tube drive circuit are composed of four transistors and a switch, effectively The conduction of the lower MOS transistor body diode during the transition from the lower MOS transistor to the upper MOS transistor conduction and / or the upper MOS transistor body diode during the transition from the upper MOS transistor to the lower MOS transistor are avoided. conduction, or only a small part of the current flows through the body diode, which effectively reduces the reverse recovery loss caused by the body diode.

The invention discloses a multi-path direct current power supply circuit, which comprises a master transformer and a first rectification filtering unit. The master transformer comprises a primary winding and a secondary winding. The primary winding of the master transformer and a first switch are connected in series with input voltage. The secondary winding of the master transformer, the first rectification filtering unit and a current sharing capacitor form a power supply loop. In the first rectification filtering unit, a first input end is connected with the second input end of the first rectification filtering unit sequentially by a first diode, a second capacitor and a fourth diode, and a second input end is connected with the first input end of the first rectification filtering unit sequentially by a third diode, a first inductor, a first capacitor and a second diode. The multi-path direct current power supply circuit can be applied to low-cost occasions in which the primary sides of the master transformers are provided with only one switching tube respectively.

A high-robust fast-recovery super-junction power semiconductor transistor and a preparation method thereof. The transistor includes an N-type drain, an N-type epitaxial layer is arranged on the N-type drain, and first and second strip-shaped P-type body regions and a first P-type body region are arranged, and at least 2 A trench gate, a heavily doped N-type source and a second P-type body region, a first field oxide layer is provided on the upper end of the trench gate, and a heavily doped N-type source is located on the upper part of the first P-type body region And confined between the trench gates, the second P-type body region is located under the heavily doped N-type source and connected to the source metal layer through the first contact metal. The method is to grow an N-type epitaxial layer on the substrate, etch a deep trench, make the first and second strip-shaped P-type body regions, and then make the trench gate, the first P-type body region, and the heavily doped N-type source , and then deposit aluminum to form the source metal layer and the first contact metal, and finally make the N-type drain. The invention can effectively improve the reverse recovery characteristic of the body diode and improve the reliability of the device.

The invention relates to a soft fast recovery diode and a manufacturing method thereof. The diode comprises an N type intrinsic region, a back N<+> buffer region, an anode metal layer and a cathode metal layer, wherein the back N<+> buffer region is formed on the back face of the N type intrinsic region; a P type emitting region is formed between the front face of the N type intrinsic region and the anode metal layer; mask oxide layers are formed symmetrically at the two ends of the anode metal layer; a P type high-resistance region is formed on the boundary of an active region; a P<+> ohmic contact layer is formed in the center of the active region; an overall lifetime control region is formed on the entire diode, and covers all structural layers of the diode; a localized lifetime control layer is positioned close to the P<+> ohmic contact layer in the P type emitting region along the axial direction of the diode; the localized lifetime control layer is positioned in a plane constructed by the P type emitting region and the P type high-resistance region along a direction which is vertical to the axial direction of the diode. The soft fast recovery characteristic of a device is realized by adopting an overall-localized lifetime control way; by arranging the high-resistance region, the snow slide resistance of the device is improved.

The invention provides a fast recovery diode and relates to the field of diodes. The fast recovery diode includes: a substrate layer; an N-type epitaxial layer located on the surface of the substrate layer; a P-type injection region located on the surface of the substrate layer and arranged on the side of the N-type epitaxial layer; a diffusion region, It is located in the top region of the N-type epitaxial layer and is separated from the P-type implantation region. The use of the fast recovery diode can solve the problem of high forward conduction voltage drop when the reverse recovery time of the fast recovery diode is reduced by the platinum expansion process in the prior art. By changing the structure of the fast recovery diode, the reverse recovery time of the fast recovery diode can be reduced. purpose of recovery time.

The invention relates to a high-efficiency Sepic soft-switching converter and its control method. On the basis of the basic Sepic circuit, a passive zero-ripple circuit, an active clamping circuit and a voltage doubler unit are introduced; the invention retains the input current of the Sepic converter Continuous characteristics, introducing a passive ripple circuit, through the series combination of coupled inductors and inductors and capacitors, the circuit is connected in parallel on the input side to achieve the zero-ripple effect of the input current, and realize the zero-ripple function of the input current, and it has nothing to do with the duty cycle. It has nothing to do with the relationship between the leakage inductance and the excitation inductance when the coupled inductance transforms the transformer, and has the characteristics of simple structure and high reliability. The active switches of the present invention all realize zero-voltage conduction, which reduces the loss caused by the switching tube, and realizes zero-voltage switching based on the Sepic converter for the first time; the use of leakage inductance, the diodes all realize zero-current turn-off, which reduces the reverse recovery loss; the voltage stress of the switching tubes is much lower than the output voltage, and low withstand voltage switching tubes can be used to improve the efficiency of the converter.

The invention discloses a combination switch. The combination switch includes a first switch, a second switch and an energy storage capacitor, the first switch and the second switch are connected in series in the same direction, the first end of the first switch is the first output end of the combination switch, and the second The end is connected in series with the first end of the second switch, the second end of the second switch is the second output end of the combination switch, and the energy storage capacitor is connected in parallel with the gate drive end of the first switch and the second end of the second switch. The combination switch of the present invention can combine the advantages of the first switch and the second switch. For example, the first switch is a MOSFET switch, and the second switch is a fast recovery diode or a Schottky diode. Then the combination switch has higher operating voltage capability and faster The performance of reverse recovery or zero reverse recovery, the reverse recovery loss is smaller or the reverse recovery loss is completely eliminated, and the circuit is simple to realize and the cost is reduced.