A dc power supply is a device that converts AC input voltage to DC format. The device is connected to an AC power source but produces a DC voltage format. These devices are used in various electronic devices. This post discusses DC power supply selection and how they work.
How does a DC power supply work?
When the power supply is connected to a power source, its transformer receives the AC input signal. The signal is usually generated by a line voltage like a power outlet or generator. The transformer adjusts the input’s amplitude to the desired levels for the DC output. The transformer also isolates the input AC signals from other internally-generated signals. From there, the signal is fed to the rectifier. This component of a DC power supply provides a rectified pulsating DC signal. A rectified pulsating DC signal does not change polarity. The devices usually contain a half or full-wave rectifier depending on the model and application.
From there, the pulsating DC signal is fed to the filter, where it is converted to a non-pulsating signal to produce DC voltage. Finally, the DC voltage passes through the regulator. The regulator smooths the signal, eliminating ripple and producing a regulated output voltage.
DC power supply selection
Now that you understand how these power supplies function, we can discuss DC power supply selection. When selecting a DC power supply, below are some top features or specifications to consider;
1.     Power System Requirements
The first thing you should consider is the system power requirements. This implies the input and output specifications. As explained earlier, DC power supplies produce DC voltage output. This means that the input is usually AC voltage. Therefore, you should look into the AC and DC output range when considering the power system requirements. The trick is to ensure that the power system requirements are compatible with the specified application. It is worth mentioning that the specifications may differ depending on the country and type of device.
2.     Output specifications
More often than not, the input voltage is usually standardized. However, this is not the case with the output. The output voltage specifications are more specific rather than standard. So the trick is to pick an output specification based on your system.
3.     Load current specification
The load current is the most important element to consider during your DC power supply selection process. Specialists recommend picking a power supply with a greater rating than the load current for a smoother operation. Going the other way will cause unexpected shutdowns and incorrect outputs.
Conclusion
During your DC power supply selection, the various options must be considered. There are three types of DC power supplies; Linear, switching, and SCR power supplies. The devices are categorized based on their mechanism to convert and transfer the AC input to DC output. Linear DC power supplies are great for computer and industrial applications. On the other hand, switching power supplies are ideal for electronic devices. Finally, SCR power supplies are commonly used in high voltage and current applications.
