In the converter disclosed by the invention, the positive pole of the DC power supply is connected to the positive pole of the input 
filter capacitor and one end of the first and third inductors; the other end of the first 
inductor is connected to the drain of the first switch tube, the 
anode of the first 
diode, and the negative pole of the first 
capacitor;  The other end of the three inductors is connected to the drain of the second switch tube, the 
anode of the second 
diode, and the 
cathode of the second 
capacitor; the 
anode of the first 
capacitor is connected to the anode of the third 
diode and one end of the second 
inductor; the 
cathode of the third diode is connected to the first  The anode of the output 
filter capacitor and one end of the DC load; the 
cathode of the first output 
filter capacitor is connected to the other end of the second 
inductor, the cathode of the fourth diode, and the anode of the second output filter capacitor; the anode of the second capacitor is connected to the anode of the fourth diode and the anode of the fourth diode.  One end of the inductor; the negative 
electrode of the second output filter capacitor is connected to the other end of the fourth inductor, the positive 
electrode of the third output filter capacitor, and the cathodes of the first and second diodes; the other end of the DC load is connected to the negative 
electrode of the input filter capacitor, the negative electrode of the third output filter capacitor, the first and second diodes  The source of the two switch tubes and the negative pole of the DC power supply.