Common types of power supply：
AC regulated power supply
The power supply that can provide a stable voltage and frequency is called AC stable power supply. The work of most China manufacturers is to stabilize the AC voltage. The following describes the classification characteristics of some AC regulated power supplies in the market.
Parameter adjustment (resonant) type
The basic principle of this kind of regulated power supply is LC series resonance. The early magnetic saturation regulator belongs to this kind. It has the advantages of simple structure, no many components, high reliability, wide voltage stabilizing range and strong anti-interference and anti overload ability The disadvantages are high energy consumption, noise, bulkiness and high cost.
The parameter regulator developed on the basis of the principle of magnetic saturation and the "magnetic amplifier regulated electronic AC regulator" (i.e. type 614) popular in China in the 1950s belong to AC regulators with this principle.
Self coupling (transformation ratio) adjustment type
1. Mechanical voltage regulation type, that is, the servo motor drives the carbon brush to move on the winding sliding surface of the autotransformer, and changes the ratio of VO to VI to realize the adjustment and stability of the output voltage. This kind of voltage regulator can range from hundreds of watts to thousands of watts. It is characterized by simple structure, low cost and small output waveform distortion; However, the sliding contact of carbon brush is easy to produce electric spark, resulting in the damage and even burning of the brush and failure; And the voltage adjustment speed is slow.
2. Change the tap type, make the autotransformer into multiple fixed taps, and use the relay or thyristor (solid-state relay) as 10 switches to automatically change the tap position, so as to realize the stability of output voltage.
This type of voltage regulator has the advantages of simple circuit, wide voltage stabilizing range (130v-280v), high efficiency (≥ 95%) and low price. The disadvantage is that the voltage stabilizing accuracy is low (± 8 ~ 10%) and the working life is short. It is suitable for supplying power to air conditioners in families.
High power compensated purified voltage regulator (including precision voltage regulator)
It uses compensation link to realize the stability of output voltage and is easy to realize microcomputer control.
It has the advantages of good anti-interference performance, high voltage stabilizing accuracy (≤± 1%), fast response (40 ~ 60ms), simple circuit and reliable operation. The disadvantages are: there is low-frequency oscillation with nonlinear loads such as computer and program-controlled exchange; High input current distortion and low source power factor; The output voltage has a phase shift to the input voltage. Units with high requirements for anti-interference function should be applied in cities. When the computer is powered, a voltage regulator about 2-3 times the total power of the computer must be used. Because it has the advantages of voltage stabilization, anti-interference, fast response speed and moderate price, it is widely used.
Switching type AC regulated power supply
It is applied to high-frequency pulse width modulation technology. The difference between it and general switching power supply is that its output must be the AC voltage with the same frequency and phase as the input side. Its output voltage wave types include quasi square wave, ladder wave, sine wave, etc. the uninterruptible power supply (UPS) in the market removes the storage power supply and charger, which is a switching AC regulated power supply with good voltage stability, strong control function and easy to realize intellectualization. It is a very promising AC regulated power supply. However, due to its complex circuit and high price, its promotion is slow.
DC stabilized power supply
DC stabilized power supply can be divided into chemical power supply, linear stabilized power supply and switching stabilized power supply according to custom, and they have different types:
Chemical power supply
The dry batteries, lead-acid batteries, nickel cadmium, nickel hydrogen and lithium-ion batteries commonly used belong to this category, each with its advantages and disadvantages. With the development of science and technology, intelligent batteries have emerged; In terms of rechargeable battery materials, American researchers have found that an iodide of manganese can be used to make environmentally friendly rechargeable batteries that are cheap, compact, long discharge time and maintain good performance after multiple charging.
Linear stable power supply
A common feature of linear stable power supply is that its power device regulator works in the linear region and stabilizes the output by adjusting the voltage drop between the regulators. Due to the large static loss of the adjusting tube, a large radiator needs to be installed to dissipate heat. Moreover, because the transformer works at power frequency (50Hz), it has a large weight.
This kind of power supply has the advantages of high stability, small ripple, high reliability, easy to make multi-channel and continuously adjustable output. The disadvantages are large volume, bulky and relatively low efficiency. There are many kinds of such stable power supply. From the output nature, it can be divided into regulated power supply, current stabilized power supply and voltage stabilized and current stabilized (bistable) power supply integrating voltage stabilized and current stabilized. From the point of view of output value, it can be divided into fixed-point output power supply, band switch adjustment type and potentiometer continuous adjustment type. From the output indication, it can be divided into pointer indication type and digital display type, etc.
Switching DC regulated power supply
A kind of stable power supply different from linear regulated power supply is switching DC regulated power supply. Its circuit types mainly include single end flyback, single end forward, half bridge, push-pull and full bridge. The fundamental difference between it and linear power supply is that its transformer does not work at power frequency, but works at tens of kHz to several megahertz. The function tube is either working in the saturation or cut-off area, that is, the switching state; Therefore, switching power supply is named.
The advantages of switching power supply are small volume, light weight, stability and reliability; Disadvantages: compared with the linear power supply, the ripple is large (generally ≤ 1% VO (P-P), and a good one can achieve more than ten MV (P-P) or less). Its power can range from a few watts to thousands of watts. The price ranges from 3 yuan to more than 100000 yuan / watt. Here are some kinds of switching power supplies according to the general habit:
1. AC / DC power supply
This kind of power supply is also called primary power supply - AC is AC and DC is DC. It obtains energy from the power grid and obtains a DC high voltage through high-voltage rectification and filtering. It is used for DC / DC converter to obtain one or more stable DC voltages at the output end. The power is from a few watts to several thousand watts, and is used in different occasions. There are many specifications and models of this kind of products. According to the needs of users, the primary power supply (AC220 input, DC48V or 24V output) in the communication power supply also belongs to this kind
2. DC / DC power supply
In the communication system, also known as secondary power supply, it is a DC input voltage provided by the primary power supply or DC battery pack, and one or more DC voltages are obtained at the output end after DC / DC conversion.
3. Communication power supply
In essence, the communication power supply is a DC / DC converter power supply, but it generally uses dc-48v or - 24V power supply, and uses the backup battery as the backup of DC power supply to convert the DC power supply voltage into the working voltage of the circuit. Generally, it is divided into central power supply, layered power supply and single board power supply, and the latter has the highest reliability.
4. Radio power supply
Radio power input AC220V / 110V, output dc13 8V, the power is determined by the power of the radio station. There are products in several amperes and hundreds of amperes In order to prevent the power failure of AC power grid from affecting the work of the radio station, a battery pack is required as backup, so this kind of power supply not only outputs a 13.8V DC voltage, but also has the function of automatic conversion of battery charging.
5. Module power supply
With the rapid development of science and technology, the requirements for power reliability and capacity / volume ratio are higher and higher, and the module power supply shows its advantages more and more. It has high working frequency, small volume, high reliability, easy installation and combined capacity expansion, so it is more and more widely used. Although there are corresponding module production in China, the failure rate is high because the production process fails to catch up with the international level.
Although the cost of DC / DC module power supply is high, from the perspective of the overall cost of the long application cycle of the product, especially the high maintenance cost and goodwill loss caused by system failure, it is cost-effective to choose this power supply module. Here, it is also worth mentioning that Roche converter circuit has the outstanding advantages of simple circuit structure, high efficiency and output voltage The ripple value of the current is close to zero.
6. Special power supply
High voltage low current power supply, high current power supply, 400Hz input AC / DC power supply, etc. can be classified into this category and can be selected according to special needs. The price of switching power supply is generally 2-8 yuan / watt, and the price of special low-power and high-power power supply is slightly higher, up to 11-13 yuan / watt.
FBelec supply power supply including:
| AC & DC Adapter |
| Switching Power Supply |
| Outdoor Power Supply |
| Power Extension Sockets |
| DC Power Supply |
| Battery Charger |
| Voltage Inverters |
| USB Adapter & USB charger |
| Lithium Battery |
| Power Extension reel |
