Distinguish the switching power supply category through nine aspects
The 9 categories of switching power supply are as follows:
According to the connection method of the switching tube and the power supply technology, the switching power supply can be divided into a series switching power supply and a parallel switching power supply.
The switch tube of the series switching power supply is connected in series between the input voltage and the output load, which is a step-down regulator circuit; while the switching tube of the parallel switching power supply is connected in parallel between the input voltage and the output load, similar to redundancy The power supply is a step-up regulator circuit.
According to the excitation method, the switching power supply can be divided into self-excitation and other excitation. In the self-excited switching power supply, a positive feedback loop is formed by the switch tube and transformer technology-high-frequency transformer to complete the self-excited oscillation, which is similar to the intermittent oscillator; while the separately excited switching power supply must be accompanied by an oscillator, the oscillator The generated switching pulse is applied to the switching tube to control the on and off of the switching tube to make the switching circuit work and have a DC voltage output.
According to modulation methods, switching power supplies like server power supplies can be divided into pulse width modulation (PWM) methods and pulse frequency modulation (PFM) methods. PWM is a method to control the stability of the output voltage by changing the switching pulse width, while PFM is when the output voltage changes, after sampling and comparing, the error value is expanded to control the switching pulse period (ie frequency), so that the output voltage is stable.
According to the size of the output DC value, the switching power supply can be divided into step-up switching power supply and step-down switching power supply, and can also be divided into high-voltage switching technology’> high-voltage switching power supply and low-voltage switching power supply.
According to the output waveform, the switching power supply can be divided into rectangular wave and sine wave circuits.
According to the output performance, the switching power supply can be divided into constant voltage and constant frequency and variable voltage and frequency conversion circuits.
According to the number of switching tubes and the connection method, the switching power supply can be divided into single-ended, push-pull, half-bridge and full-bridge. The single-ended type uses only one switch tube, the push-pull type and half-bridge type use two switch tubes, and the full-bridge type uses four switch tubes.
Switching power supplies can be divided into forward and flyback according to the energy transfer method.
According to the soft switching method, the switching power supply has current resonance type, voltage resonance type, E type and quasi E type resonance type and partial resonance type.