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

The invention relates to direct current (DC) step-up power conversion technology and discloses a current-type multi-resonance DC converter. The current-type multi-resonance DC converter comprises a square-wave current source generator, a multi-resonance network and a rectification filtering output unit which are sequentially connected in series, and is characterized in that: the multi-resonance network comprises a transformer, a parallel resonant inductor, a parallel resonant capacitor and a serial resonant inductor, wherein the serial resonant inductor is connected with a primary side of the transformer; the rectification filtering output unit comprises a diode rectifying circuit and a filtering capacitor which is connected with an output end of the diode rectifying circuit in parallel.

The invention discloses a high-gain isolated-type active clamping soft-switched DC-DC convertor, and belongs to the technical field of convertors. The convertor comprises a current multiplication loop, a transformer and a switched capacitance loop; the current multiplication loop comprises a voltage source Vin, two input inductors L1 and L2, a clamping capacitor Cc, two main power switch tubes S2 and S4, two auxiliary power switch tubes S1 and S3, external capacitors CS1, CS2, CS3 and CS4 of the four power switch tubes S1-S4, and a transformer primary coil shunt inductor L; the switched capacitance loop comprises four rectifier diodes which include D1, D2, D3 and D4, one resonance inductor Llk, two resonant capacitors C11 and C12, two output capacitors C21 and C22, and a load resistor R. The high-gain isolated-type active clamping soft-switched DC-DC convertor has the advantages of having high gain, being small in ripple of input current, small in ripple of output voltage, low in cost, and high in efficiency, and can be applied to occasions of conversion from direct current to direct current in low-voltage and large-current systems like a photovoltaic power generation system and a fuel-cell power generation system.

The invention discloses a phase-shift full-bridge converter circuit which comprises a transformer, a lead bridge arm, a lag bridge arm and an output circuit. The lead bridge arm is formed by serially connecting a first MOS tube and a second MOS tube, the connection point of the two MOS tubes is sequentially connected with one end of a primary side of the transformer through a capacitor and a resonant inductor, and the capacitor and the resonant inductor are connected in series. The lag bridge arm is formed by serially connecting a third MOS tube and a fourth MOS tube, the connection point of the two MOS tubes is connected with the other end of the primary side of the transformer, and input direct-current voltage is applied to the positions between the connection point of the first MOS tube and the second MOS tube and the connection point of the third MOS tube and the fourth MOS tube. The output circuit is composed of four rectifier diodes and an output capacitor. The voltage of the two ends of the output capacitor is output direct-current voltage. The invention further discloses a control method of the phase-shift full-bridge converter circuit. By means of the circuit and the method, full-bridge soft switching of the phase-shift full-bridge converter circuit is achieved, switching loss is reduced, and efficiency is improved.

This invention discloses one resonance direct flow flexible inverter circuit, which comprises one direct current power, one control circuit, one inverter bridge and drive load, wherein, the direct current power and inverter bridge are added with aid resonance circuit composed of three aid switches, six diodes, three capacitors and one inductance; when the power parts converts from status to another one, the control circuit sends control signal for reasonable aid switch V1, V2 and V3.

The invention discloses a soft switching inverting circuit and a control method thereof. The soft switching inverting circuit comprises a control circuit, a direct current power source, a partial pressure circuit and an inverting bridge, wherein a resonance auxiliary circuit is connected between the partial pressure circuit and the inverting bridge, the resonance auxiliary circuit comprises two auxiliary switches V and Tr, a single-phase inverting bridge, a capacitor Cr, a diode D and an inducer Lr, the single-phase inverting bridge consists of diodes Dr1, Dr2, Dr3 and Dr4, and the resonance auxiliary circuit is connected with the control circuit and is used for controlling the switching on and off of the auxiliary switches V and Tr according to signals dV and dTr transmitted by the control circuit; and the soft switching inverting circuit has the control method that the control circuit transmits a control signal to reasonably control the switching on and off of the auxiliary switches V and Tr when a power device of the inverting bridge needs to be switched into another switching status from one switching status. After the invention is used, the defects that the additional cost is high, the control is complex, the power density of the inverter is low and the like in the prior art are overcome, the power density of the inverter is improved, the electromagnetic interference is reduced, and the control method is simple and easy to realize.

The invention provides a high-speed doubly salient starter generator controller and a control method thereof. The high-speed doubly salient starter generator controller is characterized by comprisinga generator, a generator controller, a three-phase full-bridge circuit, a phase current comparison circuit, an exciting current control circuit, an FPGA control circuit, a DSP control circuit and an output capacitor C. According to a three-phase full-bridge topology of SiC MOS, hardware multiplexing of starting and power generation is realized, and compared with the three-phase full-bridge topology of a Si IGBT device, the three-phase full-bridge topology of SiC MOS overcomes the defect that the IGBT conduction voltage drop cannot be lower than a certain fixed value when a switching tube is conducted, so that the conduction loss is reduced; according to the FPGA duty ratio controlled three-phase current comparison circuit, the circuit is simple and easy to implement; and a novel phase sequence detection and zero calibration method of an electro-magnetic doubly salient motor is simpler and more efficient than a method of dragging the electro-magnetic doubly salient motor and then judging a phase sequence and a zero position through armature voltage.

The invention relates to a coupling inductance double tube direct current converter with a charge pump. The coupling inductance double tube direct current converter with the charge pump is characterized in that the coupling inductance double tube direct current converter 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 first clamping circuit, a second clamping circuit, diodes 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 a diode circuit after undergoing secondary boosting of the first charge pump boosting unit, the first clamping circuit is used for clamping the first boosting circuit, 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, and the second clamping circuit is used for clamping the second boosting circuit. Voltage stress and current stress of a main power switch tube are small, the diodes are switched off naturally with zero current, the reverse recovery problem does not exist, and EMI of the circuits is small.

The invention relates to an electric source five-level transmission circuit employing a transient electromagnetic method. The electric source five-level transmission circuit is formed by connecting a control and protection circuit to an earth load through a three-phase controllable rectifier circuit, a DC/DC and a five-level transmission bridge circuit. The electric source five-level transmission circuit is characterized in that the five-level transmission bridge circuit is connected to a reference frequency generation circuit through a drive and protection circuit, a synthesis circuit and a frequency dividing circuit, and the synthesis circuit is connected to a rising edge control circuit, a falling edge control circuit, a flat-top control circuit and a synchronous circuit. The bearable highest voltage of each power device in the circuit is 1/4 of a direct current bus voltage; an improved five-level topology clamps the voltage of a clamping diode within a single level; the problem of reverse recovery of multi-level output clamping diodes is solved; when any level is output from the circuit, eight MOSFETs are kept at an on state and eight MOSFETs are turned off; and the adjacent levels are switched only by switching two MOSFETs, so that good stability is ensured. Compared with conventional equipment, the electric source five-level transmission circuit is low in value of dv/dt; and insulation impact and electromagnetic interference are reduced.

The invention discloses a single-tube converter, which solves the problems of parasitic oscillation and reverse recovery of the output rectifier diode of a traditional single-ended forward converter with a magnetic reset winding; the filter circuit is only a capacitor connected in parallel in the converter output, reducing the use of magnetic components.

The present invention belongs to the power source converter field and relates to an efficient AC-DC power source converter. The efficient AC-DC power source converter comprises an PFC circuit; the PFC circuit is connected with a DC/DC converter through an intermediate voltage bus-bar; the intermediate voltage bus-bar is provided with a positive pole end and a negative pole end; the intermediate voltage bus-bar is connected with a bus-bar capacitor; one end of the bus-bar capacitor is connected with a bi-directional DC/DC converter; the other end of the bus-bar capacitor is connected with the negative pole end of the intermediate voltage bus-bar; and the bidirectional DC/DC converter is connected with the positive pole end of the intermediate voltage bus-bar. The power balance of input and output can be realized through controlling the bidirectional DC/DC converter; the voltage of the bus-bar capacitor can have a wide change range; and therefore, energy stored in the bus-bar capacitor can be fully utilized, the fluctuation of the voltage of the intermediate bus-bar will not be too large, and the high conversion efficiency of later-stage DC/DC can be maintained.

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.