Detailed explanation of linear regulated power supply, switching power supply and phased power supply
Introduction of linear regulated power supply, switching power supply and phased power supply
According to different conversion modes, DC power supply can be divided into three types: linear regulated power supply, switching power supply and phased power supply.
1. The linear regulated power supply can meet the requirements of DC voltage and power supply quality (precision, ripple, etc.) required by electronic circuits, but there are two major shortcomings: First, the regulator VT works in a linear amplification state, with great loss and low power supply efficiency; Second, a power frequency transformer T is needed to make the whole power supply bulky and heavy.
2, switching power supply is to overcome the shortcomings of linear regulated power supply, named because its power (power) electronic devices always work in the switching state.
3. Phased power supply is the abbreviation of thyristor phase control power supply. Like the switching power supply, the power electronic devices in the phase-controlled power supply are also working in the switching state, but their working frequency is power frequency (50 Hz) instead of high frequency. In contrast, a significant advantage of phased power supply is its simple circuit and convenient control. Its main disadvantage is to have a power frequency transformer, which makes the whole power supply bulky and heavy. The ripple frequency of DC output voltage of this phase-controlled power supply is only several times of the power frequency (2 times for single-phase full-bridge control and 6 times for three-phase full-bridge control), so a larger filter is needed to achieve better filtering effect. However, the ripple frequency of DC output voltage of switching power supply is very high, often above 20 kHz, so only a small filter is needed. Because of the low switching frequency of phased power supply, its response speed to control is slower than that of switching power supply.
Traditionally, switching power supply refers to the DC power supply in which power (power) electronic devices work in high-frequency switching state, so it is also called high-frequency switching power supply, and phased power supply is not included in switching power supply.
