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.