1. Main circuit
Impulse current limiting: limit the impulse current at the input side at the moment of power on.
Input filter: its function is to filter the clutter existing in the power grid and prevent the clutter generated by the machine from being fed back to the power grid.
Rectification and filtering: the pwa printed wiring assembly and AC power supply of the power grid is directly rectified into smoother DC power.
Inverter: convert the rectified DC into high-frequency AC, which is the core of high-frequency switching power supply.
Output rectification and filtering: provide stable and reliable DC power supply according to load requirements.
2. Control circuit
On the one hand, samples are taken from the output end and compared with the set value, and then the inverter is controlled to change its pulse width or pulse frequency to stabilize the output. On the other hand, according to the data provided by the test circuit and identified by the protection circuit, the control circuit is provided to carry out various protection measures for the power supply.
3. Detection circuit
Provide various parameters and instrument data in operation in the protection circuit.
The typical circuit of single ended forward switching power supply is shown in Figure 4. This circuit is similar to the single ended flyback circuit in form, but its working conditions are different. When the switch tube VT1 is turned on, VD2 is also turned on
When on, the power grid transmits energy to the load, and the filter inductor L stores energy; When the switch VT1 is turned off, the inductance L continues to release energy to the load through the freewheeling diode VD3.
