DC Voltage Regulators and AC Voltage Regulators
Can provide stable AC power supply or DC power supply for the load of electronic devices. Including AC voltage stabilized power supply and DC voltage stabilized power supply two categories.
AC voltage stabilized power supply is also known as AC voltage stabilizer. With the development of electronic technology, especially electronic computer technology applied to various industrial, scientific research fields, a variety of electronic equipment require stable AC power supply, direct power supply has been unable to meet the needs of the grid, the emergence of AC regulated power supply to solve this problem. Commonly used AC voltage regulator power supply: ① ferromagnetic resonant AC voltage regulator. By saturated choke and the corresponding capacitor, with constant voltage volt-ampere characteristics. ② magnetic amplifier type AC voltage regulator. Magnetic amplifier and autotransformer in series, the use of electronic circuits to change the impedance of the magnetic amplifier to stabilize the output voltage. ③Sliding type AC voltage regulator. Stabilize the output voltage by changing the position of the sliding contact of the transformer. Inductive AC voltage regulator. By changing the phase difference between the secondary and primary voltages of the transformer, the output AC voltage is stabilized. ⑤ Thyristor AC voltage regulator. The thyristor is used as the power adjustment element. High stability, fast response and no noise. However, it causes interference to communication equipment and electronic equipment.After 1980s, three new types of AC voltage stabilized power supply appeared: compensated AC voltage stabilizer. Numerical control type and stepping type AC voltage regulator. Purification type AC voltage regulator. It has a good isolation effect and can eliminate the spike interference from the power grid.
DC regulated power supply Also known as DC voltage regulator. Most of its power supply is AC power supply, when the AC power supply voltage or load resistance changes, the direct output voltage of the regulator can be kept stable. The parameters of the voltage regulator are voltage stability, ripple factor and response speed. The former indicates the effect of changes in the input voltage on the output voltage. Ripple coefficient indicates that under rated operating conditions, the size of the AC component of the output voltage; the latter indicates that when the input voltage or load changes drastically, the time required for the voltage to return to normal value. DC regulated power supply is divided into two categories of continuous conductive and switching. The former by the transformer to single-phase or three-phase AC voltage to the appropriate value, and then rectified, filtered, to obtain unstable DC power supply, and then by the regulator circuit to get a stable voltage (or current). This power line is simple, small ripple, mutual interference is small, but the volume is large, more consumables, low efficiency (often less than 40% to 60%). The latter to change the adjustment element (or switch) on-off time ratio to regulate the output voltage, so as to achieve voltage regulation. This type of power supply power consumption is small, the efficiency can be up to 85% or so. Therefore, it has developed rapidly since the 1980s. From the mode of operation can be divided into: ① controlled rectifier type. Change the on-time of the thyristor to adjust the output voltage. ② Chopper type. The input is unstable DC voltage, to change the on-off ratio of the switching circuit to get unidirectional pulsating DC, and then filtered to get a stable DC voltage. ③Converter type. Unstable DC voltage is first transformed into high-frequency alternating current by the inverter, and then sampled from the new DC output voltage obtained after transformer, rectifier, filter, and feedback control of the inverter operating frequency to achieve the purpose of stabilizing the output DC voltage.
