Switching power supply is a kind of power supply widely used in various electronic devices, including DC switching power supply and AC switching power supply.
switched mode power supplies can provide stable, reliable and efficient voltage and current output, making it the preferred power supply for many electronic devices. However, in some cases, a single switching power supply output cannot meet the demand, and multiple switching power supply outputs need to be used in parallel. In this article, we will introduce in detail how to use switching power supply outputs in parallel.
Principle of parallel connection
Connecting multiple switching dc power supply outputs in parallel allows them to be combined into a larger output power. The principle of parallel connection of power supplies is simple: connect all the positive poles of the power supplies and connect all the negative poles of the power supplies.
Doing so can coordinate all the power supplies with each other and jointly output a larger current and voltage. Multiple power supplies connected in parallel, each power supply outputs the same voltage and current. The more power supplies are output in parallel, the greater the output power.
Applicable occasions for power supply parallel connection
Multiple switched mode power supplies outputs connected in parallel can be applied to a variety of electronic devices, such as high-power LED lighting, high-speed motor drive, inverter, etc.
In these applications, the output voltage or current of a single switching power supply cannot meet the demand. Connecting multiple switching power supplies in parallel can increase the output power and meet the needs of high power, high voltage and high current applications.
Precautions for power supply parallel connection
Power supply parallel connection must follow certain specifications, otherwise it will lead to unstable power output, shortened power life, equipment damage and other problems. Here are a few things to note:
The power supply model must be consistent
Multiple switching power supplies in parallel must use the same model of high voltage switching power supply to ensure that their output voltage and current are the same. If different models of power supplies are connected in parallel, the power supply output power and stability may be affected.
The length of the cables connected in parallel must be consistent
For multiple switching power supplies connected in parallel, their output voltage and current must be within the same voltage and current range. However, different lengths of connecting wires will increase impedance changes and voltage drops, which will cause unstable power output. Therefore, the cable length must be the same, and the wire diameter should also be the same to ensure the stability of the power supply output voltage and current.
The output ends of the switching power supply must be connected to the load separately
Multiple switching power supplies connected in parallel must be connected to different loads separately to make full use of the output power.
If the output ends of multiple power supplies share a load, the failure of one of the power supplies will cause the output current of the power supply sharing the load to be too large, thereby damaging the load.
The output current of parallel power supplies must be equal
When multiple switching power supplies are connected in parallel, their output currents must be equal to avoid the situation where the output current of a single power supply is too large.
If the output currents of multiple power supplies are different, the power supply with a smaller current may be overloaded during operation, thereby affecting the normal operation of the power supply.
When the power supply outputs are connected in parallel, the cable interface must be protected
When multiple dc switching power supply outputs are connected in parallel, the connecting cables between the power supplies must be protected. Because under high power, high voltage and high current, the joints may become loose, resulting in arcing.
At the same time, the joints of the parallel connection of the power supply output must also be regularly inspected and maintained to prevent problems such as poor contact of the joints and aging of the insulation materials.
Conclusion
The parallel connection of the variable switch mode power supply output can greatly increase the output power and meet the needs of high power, high voltage and high current. When connecting the power supply outputs in parallel, attention should be paid to standardizing the connection to ensure the stability of the power supply output voltage and current.
Only when connected reasonably can the parallel outputs of multiple switching power supplies maintain long-lasting operation and provide power support for various electronic devices.
