Detailed Explanation of Linear Regulated Power Supplies, Switching Power Supplies, and Phase-Controlled Power Supplies
1. Linear stabilized power supply can meet the high and low requirements of DC voltage and power supply quality (accuracy, ripple, etc.) required by electronic circuits, but it has two major disadvantages: first, the adjustment tube VT works in a linear amplification state, with high losses and low power efficiency; Secondly, a power frequency transformer T is required to make the entire power supply bulky and heavy.
2. Switching power supply emerged to overcome the shortcomings of linear regulated power supply, named after its power electronic devices always working in a switching state.
3. Phase controlled power supply is the abbreviation for thyristor phase controlled power supply. Similar to switching power supplies, the power electronic components in phase controlled power supplies also operate in a switching state, except that their operating frequency is at the power frequency (50Hz) rather than high frequency. In contrast, a significant advantage of phased control power supply is its simple circuit and convenient control. Its main disadvantage is also the need for a power frequency transformer, which makes the entire power supply bulky and heavy. In addition, the ripple frequency of the DC output voltage of the phase controlled power supply is only a few times that of the power frequency (2 times for single-phase full bridge control and 6 times for three-phase full bridge control), requiring a larger filter to achieve better filtering effect. The ripple frequency of the DC output voltage of the switching power supply is very high, often above 20kHz, so only a small filter is needed. Due to the low switching frequency of phase controlled power supplies, their response speed to control is also slower than that of switching power supplies.
According to convention, a switching power supply specifically refers to a DC power supply in which power electronic devices operate in a high-frequency switching state, and is therefore also known as a high-frequency switching power supply. Phase controlled power supplies are not included in switching power supplies.
