33results about How to "Resolve reverse recovery" patented technology

The present invention relates to an AC / DC converter (1) of the type having an AC / DC conversion stage (2) and a DC / DC conversion stage (3), the AC / DC conversion stage (2) comprising an input filter stage (4), an input rectifier stage (5) and a tracking boost converter stage. The boost converter stage in turn comprises an input choke (10), a boost diode (16) and a bulk capacitor (17). The bulk capacitor (17) is arranged to store a range of voltages substantially proportional to the input voltage of the converter. The DC / DC stage (3) is arranged to receive the range of voltages from the bulk capacitor (17) and is controllable to provide a desired DC output regardless of the voltage received from the bulk capacitor (17). This is achieved through careful combination of components and use of output feedback control to control the voltage applied to an isolated transformer (41) in the DC / DC stage.

The invention discloses a high-gain isolated type direct current-direct current (DC-DC) convertor for fuel-cell power generation and belongs to the technical field of convertors. The convertor comprises an input current multiplier, a switch capacity multiplier, a clamping circuit and a transformer. The input current multiplier comprises a first input inductor, a second input inductor, a first switch tube and a second switch tube. The clamping circuit comprises a clamping capacitor Cc, a first clamping switch tube and a second clamping switch tube. The switch capacity multiplier comprises a first resonant capacitor, a second resonant capacitor, a first output capacitor C2a, a second output capacitor C2b and four rectifier tubes. The primary side of the transformer is connected with the input current multiplier and the clamping circuit respectively, and the secondary side of the transformer is connected with the switch capacity multiplier. When high-gain isolated type DC-DC convertor is applicable to the fuel-cell power generation and grid connection, the convertor needs an occasion with high gain, small input current ripple and high efficiency, and the convertor is also applicable to other types of new energy power generation including low-output-voltage power generation and the like.

The invention provides a high voltage rise DC / DC converter. The high voltage rise DC / DC converter can convert a low voltage direct current into a high voltage direct current, can achieve soft switching, and has high work efficiency. The high pressure rise DC / DC converter comprises two portions which are respectively a boost circuit unit and a voltage rise unit. The boost circuit unit is composed of two power switches S1 and S2, and a primary side L 1 of a coupling inductor. A subsidiary side L 2 of the coupling inductor, a capacitor c and a diode D form the voltage rise unit of the high voltage rise DC / DC converter. The voltage rise unit is equivalent to a controllable direct current voltage source, and voltage of the voltage rise unit is related to turn ratios N of the subsidiary side and the primary side of the coupling inductor, and the duty ratio D of a switching tube S1. Compared with an existing high voltage rise DC / DC converter, the high voltage rise DC / DC converter is high in voltage gain, low in voltage stress of devices, and high in efficiency.

The invention relates to a coupling inductance ZVS / ZCS double tube direct current converter with a charge pump. The coupling inductance ZVS / ZCS double tube direct current converter with the charge pump comprises a direct-current power source, a first boosting circuit, a second boosting circuit, a first charge pump boosting unit, a second charge pump boosting unit, a switch circuit and a load, wherein an output voltage of the direct-current power source is output through two paths, one path of the output voltage is input into the first charge pump boosting unit after undergoing primary boosting of the first boosting circuit and input to one end of the load through the switch circuit after undergoing secondary boosting of the first charge pump boosting unit, and the other path of the output voltage is input to the second charge pump boosting unit after undergoing primary boosting of the second boosting circuit and input to the other end of the load after undergoing secondary boosting of the second charge pump boosting unit. The circuits are small in size and high in conversion efficiency, voltage stress of power switch tubes is low, current stress of the power switch tubes is small, and conduction loss of the power switch tubes is small; zero voltage switching can be achieved, and switching loss is small; all power diodes can be switched off naturally with zero current, the reverse recovery problem does not exist, and EMI of the circuits is small.

The invention provides a DC-DC (Direct Current to Direct Current) converter with high efficiency, high gain and low voltage and current stresses. In the DC-DC converter, a direct-current power supply, a switch tube, a first diode, a second diode, a fourth diode, a fifth diode, a first inductor, a third inductor, a first capacitor, a third capacitor and a fourth capacitor construct an input-grade Boost converter; the first capacitor, the switch tube, a third diode, a sixth diode, a seven diode, an eighth diode, a ninth diode, a second inductor, a fourth inductor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor, a second capacitor and a load construct an output grade Boost converter. The input Boost converter and the output Boost converter are connected to the second inductor and the fourth inductor to serve as resonant inductors, so that the zero current turning-on of the switch tube is realized; meanwhile, the zero current turning-off of each diode is realized. The gain of the converter is 6 / (1-D)2, and the voltage stress of the switch tube is one third that of the output voltage.

The invention provides a high-efficiency high-gain DC-DC converter with double coupling inductors. The high-efficiency high-gain DC-DC converter with the double-coupling inductors comprises an input level Boost converter with a first coupling inductor and an output level Boost converter with a second coupling inductor. The input level Boost converter is composed of a direct-current power supply, a switching tube, a first diode, a second diode, a fourth diode, a fifth diode, the first coupling inductor, a first capacitor, a second capacitor and a fifth capacitor. The output level Boost converter is composed of a second capacitor, a switching tube, a third diode, a sixth diode, a seventh diode, a third capacitor, a fourth capacitor, a sixth capacitor, the second coupling inductor and loads. The inductors are adopted in the input level Boost converter and the output level Boost converter. Zero-current switching-on of the switching tubes is achieved, and meanwhile zero-current switching-off of each diode tube is achieved. The converter is high in gain which can reach (2+N1)(2+N2) / (1-D)2, and the voltage stress of the switching tubes is low and is only 1 / (2+N2) of the output voltage.

The invention provides a high-efficiency high-gain DC-DC (Direct Current to Direct Current) converter with a coupling inductor. A voltage-doubled output input-stage Boost converter is formed by a direct-current power supply, a switching tube, a first diode, a second diode, a fourth diode, a fifth diode, a first inductor, a second inductor, a first capacitor, a third capacitor and a fourth capacitor; an output-stage Boost converter with coupling inductor is formed by the first capacitor, the switching tube, a third diode, a second capacitor, a fifth capacitor, a sixth capacitor, the coupling inductors and a load. The input-stage Boost converter introduces the second inductor as a resonant inductor and the output-stage Boost converter adopts the coupling inductor, so that the zero current turning-on of the switching tube is realized and the zero current turning-off of each diode is realized at the same time. The converter has the advantages that the gain is extremely high and can reach 2(2+N) / (1-D)2, and the voltage stress of the switching tube is very low and is only 1 / (2+N).

A transfer DC-DC inverter of zero-voltage and zero-current type is prepared as forming booting DC-DC inverter by master switch tube A, power diode D and energy storage inductance L, realizing zero-voltage and zero-current on-off state of master switch tube A and realizing zero-current soft switch of auxiliary switch tubes B and C by utilizing auxiliary switch tube B to control auxiliary resonant network A and utilizing auxiliary switch tube C to control auxiliary resonant network B.

The invention discloses a phase-shifting full-bridge conversion circuit, which includes a transformer; the leading bridge arm is composed of a MOS tube 1 and a MOS tube 2 connected in series, and the connection point of the two MOS tubes is connected to the primary side of the transformer through a capacitor and a resonant inductance in sequence. The capacitor and the resonant inductor are connected in series; the lagging bridge arm is composed of three MOS tubes and four MOS tubes connected in series, the connection point of these two MOS tubes is connected to the other end of the primary side of the transformer, and the input DC voltage is added between the connection point of MOS tube one and MOS tube three and the connection point of MOS tube two and MOS tube four; the output circuit is composed of four rectifier diodes and an output capacitor; the two ends of the output capacitor are output the DC voltage. The invention also discloses a control method for the phase-shifting full-bridge conversion circuit. The invention realizes the full-bridge soft switch of the phase-shifting full-bridge conversion circuit, reduces switching loss and improves the efficiency of the whole machine.