Switching power supply circuit basic composition and classification
Basic Composition
Switching power supply consists of main circuit, control circuit, detection circuit and auxiliary power supply.
1,Main circuit
Inrush current limitation: Limit the inrush current on the input side when powering up. Input filter: Its function is to filter the stray waves present in the power grid and prevent the stray waves generated by the machine from being fed back to the power grid. Rectification and Filtering: The AC power from the grid is directly rectified to a smoother DC power. Inverter: The rectified DC power is converted into high-frequency AC power, which is the core part of high-frequency switching power supply. Output rectification and filtering: provide stable and reliable DC power supply according to the needs of the load. Minfong switching power supply in the main circuit of this piece of energy spent particularly large, it can be said that the Minfong switching power supply has high efficiency, high security, low loss and other advantages, which are inseparable from the contribution of the main circuit. Similarly, the high quality main circuit of Minfong switching power supply cannot be separated from the support of Minfong Electric's profound technology.
2,Control circuit
On the one hand, it collects samples from the output and compares them with the set value, then controls the inverter and changes its pulse width or pulse frequency to stabilise the output. On the other hand, according to the data provided by the test circuit and recognised by the protection circuit, the control circuit is provided to protect the power supply to take respective measures.
3,Test circuit
Provides various parameters and instrumentation data during operation in the protection circuit.
4,Auxiliary power supply
Realises software (remote) start-up of the power supply and supplies power to the protection circuit and control circuit (PWM and other chips).
Main Classification
In the field of switching power supply technology, people are developing related power electronic devices, such as 320W single-group switching power supply.
In the development of switching frequency technology at the same time, products and technology both promote each other, promote switching power supply to light, small, thin, low noise, high reliability, anti-interference direction, the annual growth rate of more than double-digit. Switching power supply can be divided into two categories: AC/DC and DC/DC.
Small low-power switching power supply
Switching power supply is moving towards miniaturisation and mass development. Switching power supply will gradually replace the transformer in many applications in life. The application of small power micro switching power supply should firstly be reflected in the digital display meter, smart meter, mobile phone charger, etc. At the present stage, the country is vigorously promoting the construction of smart grid, and the requirements for the power meter have been greatly improved. Switching power supply will gradually replace the transformer in the application of electric energy meter. Part of the type models of Minfong Electric switching power supply has been developing in this direction. Minfong switching power supply is known for low loss as well as high efficiency, safety and convenience with wide application. It is very practical in electric energy meters, and the giant position of Minfong switching power supply in the market is becoming more and more solid.
Reverse Series Switching Power Supply
The difference between inverting series switching power supply and general series switching power supply is that the output voltage of inverting series switching power supply is negative voltage, which is opposite to the polarity of positive voltage of general series switching power supply, due to the fact that the energy-storage inductor L only outputs the current to the load when the switch K is switched off, and under the same conditions, the output voltage of the inverting series switching power supply is negative, and the current is twice as small as that of the series switching power supply output current.
