Basic concepts of switching power supply
With the development of power electronics technology, the relationship between power electronic equipment and people's work and life has become increasingly close, and electronic equipment cannot do without reliable power sources. In the 1980s, computer power supplies fully realized the switch power supply, taking the lead in completing the power supply replacement of computers. In the 1990s, switch power supplies have entered various fields of electronic and electrical equipment, such as program-controlled switches, communication, and electronic detection equipment power supplies Switching power supplies have been widely used in control equipment such as power supplies, which has further promoted the rapid development of switching power supply technology. Switching power supply is a type of power supply that utilizes modern power electronics technology to control the time ratio of switching transistors on and off, maintaining a stable output voltage. Switching power supply is generally composed of pulse width modulation (PWM) control IC and MOSFET. Compared to linear power supplies, the cost of both increases with the increase of output power, but their growth rates vary. The cost of a linear power supply is actually higher than that of a switching power supply at a certain output power point, which is a cost reversal point. With the development and innovation of power electronics technology, switching power supply technology is constantly innovating, and this cost reversal point is increasingly moving towards the low output power end, providing a wide range of development space for switching power supplies. High frequency switching power supply is the direction of its development. High frequency makes switching power supply miniaturized and enables it to enter a wider range of applications, especially in high-tech fields, promoting the miniaturization and portability of high-tech products. In addition, the development and application of switching power supplies are of great significance in energy conservation, resource conservation, and environmental protection.
Switching power supply is a type of power supply that uses a circuit to control the switch tube for high-speed channel on and off. It converts direct current into high-frequency alternating current and provides it to the transformer for voltage transformation, thereby generating the required set or sets of voltages! The reason for switching to Huawei's high-frequency AC power is that the efficiency of high-frequency AC in the transformer transformation circuit is much higher than that of 50HZ. Therefore, switching transformers can be made very small and not very hot when working! The cost is very low. If 50HZ is not converted to high-frequency, then the switching power supply is meaningless!! Switching transformers are not mysterious. They are just ordinary transformers! This is the switching power supply. Switching power supplies can generally be divided into two types: isolated and non isolated. The isolated type must have a switching transformer, while the non isolated type may not necessarily have one.
When the power is the same, the higher the switching frequency, the smaller the volume of the switching transformer, but the higher the requirement for the switching transistor; The secondary of a switching transformer can have multiple windings or one winding with multiple taps to obtain the required output; Generally, some protective circuits should also be added, such as no-load and short circuit protection, otherwise it may burn out the switch power supply.
