Switching DC stabilized power supply is a type of power supply that is different from linear stabilized power supply. Its circuit types include full-bridge, push-pull, half-bridge, single-ended forward, and single-ended flyback. Unlike linear power supply, this power supply does not operate at power frequency, but instead, its transformer operates at frequencies ranging from tens of kilohertz to several megahertz. In addition, the function tube works either in the saturation region or in the cut-off region, which is why it is called a switching power supply.
Switching power supplies have several advantages such as their small size, light weight, and stable and reliable performance. However, one disadvantage is that they have a larger ripple compared to linear power supplies, with ripple levels generally being less than or equal to 1% VO (PP). Nevertheless, high-quality switching power supplies can achieve ripple levels of just a few millivolts (PP) or even less. These power supplies are available in a wide range of power capabilities, ranging from a few watts to several kilowatts. In terms of price, they can vary significantly, with prices ranging from as low as 3 yuan to more than 100,000 yuan per watt. Now let's take a closer look at the various types of switching power supplies based on their general classifications.
1. AC/DC power supply
The primary power supply, also known as AC/DC power supply, draws energy from the power grid and rectifies it to obtain a stable DC voltage. This voltage is then used by a DC/DC converter to generate one or more stable DC voltages for different applications, ranging from a few watts to several kilowatts. With numerous specifications and models, such power supplies are widely used in various fields. For instance, communication power supplies with AC220 input and DC48V or 24V output are classified as primary power supply products.
2. DC/DC power supply
In the communication system, the secondary power supply is alternatively known as the backup power supply. It is responsible for receiving a DC input voltage from either a primary power supply or a DC battery pack. Once the input voltage is converted through a DC/DC conversion process, the output end obtains one or multiple DC voltages. Thus, the secondary power supply ensures a reliable and continuous power source for the system's functioning.
3. Communication power
The communication power supply functions as a DC/DC converter power supply, where it typically operates using DC -48V or -24V as its power source. To convert the DC supply voltage into the necessary working voltage for the circuit, it relies on a backup battery in case of power failure. There are three different variations of this power supply: central power supply, layered power supply, and single-board power supply. Among these options, the single-board power supply is considered the most dependable and trustworthy.
4. Radio power supply
The radio requires an AC input of either 220V or 110V, and outputs a DC voltage of 13.8V. The actual power output depends on the type of power supply, which can range from several amperes to hundreds of amperes. To prevent power failures from disrupting the radio's operations, a battery pack is necessary for backup. Therefore, the power supply is not only capable of outputting a 13.8V DC voltage but also features an automatic function for charging the battery pack.
5. Module power supply
As science and technology continue to advance, there is an increasing demand for power supply reliability and capacity/volume ratio. In response, module power supply has proven to be exceptionally superior and has witnessed widespread adoption. However, although China has its own domestically produced modules, they often suffer from a high failure rate due to the inadequacy of the production process when compared to international standards.
The DC/DC module power supply may come at a high cost, but it remains a cost-effective choice in the long run. With a long product cycle, it addresses the concerns over maintenance expenses and potential damage to the system's reputation in the event of a failure. In addition, the Rogowski converter circuit presents itself as an excellent option, considering its simplicity in circuit structure, high efficiency, and an almost-zero output voltage and current ripple value.
6. Special power supply
This category includes power supplies such as high voltage low current power supply, high current power supply, and 400Hz input AC/DC power supply, which can be selected based on specific needs. The price range for switching power supply is typically 2-8 yuan per watt, while special low-power and high-power power supplies may cost slightly more, ranging from 11-13 yuan per watt. It is important to consider these factors when choosing the right power supply for your requirements.
