High-gain DC-DC converter

The invention relates to a high-gain DC-DC converter, which belongs to the technical field of DC converters and is characterized in that the high-gain DC-DC converter comprises a boosting unit, a coupling inductance unit and an output filtering unit, and an input power supply Vin is output to a load R after sequentially passing through the boosting unit, the coupling inductance unit and the output filtering unit which are connected in series; wherein the boosting unit consists of a switching tube Q, a boosting inductor L, a capacitor C1 and a diode D1; the coupling inductor unit is composed of a transformer, a leakage inductor Lk, an excitation inductor Lm, diodes D1-D3 and capacitors C2-C4. The output filtering unit is composed of a diode D4 and a filtering capacitor Co. The high-gain DC-DC converter adopts one-way conversion, solves the problems that a traditional boost converter is large in device number, large in circuit current ripple, high in circuit loss and high in switching voltage stress, and improv