Single-ended forward converter electrical schematic diagram

As shown in the figure, when the switch V1 is turned on, the input voltage Uin is all added to both ends of the primary coil W1" of the converter. The induced voltage generated on the demagnetization coil W1"" causes the diode V2 to cut off, and the secondary coil W2 The induced voltage turns on V3 and transfers the energy of the input current to the inductor Lo, capacitor C and the load; at the same time, a magnetizing current is established in the transformer. When V1 is turned off, V3 is turned off, and the polarity of the voltage on Lo is reversed. and continue to supply power to the load through the freewheeling diode V4. The magnetizing current in the transformer is released to the input power supply Uin through W1"" and V2 and is demagnetized; W1"" has a clamping effect, and the voltage on it is equal to the input voltage Uin. Before V1 is turned on again, the demagnetization current in T must be released to zero, that is, the magnetic flux in T must be reset. Otherwise, the transformer T will be saturated and V1 will be damaged. Usually W1"=W1"" is used, and a double line is used. The duty cycle of the parallel-winding coupling mode is <0.5, otherwise T will be saturated. The single-ended forward converter waveform is shown in the figure below.