Adjustable power supply adopts the current international advanced high-frequency modulation technology. Its working principle is to widen the voltage and current of the switching power supply, realize the wide range of voltage and current adjustment, and expand the application of the current DC power supply.
The control chip of the DC regulated power supply adopts the relatively mature imported components, and the power components adopt the latest high-power devices developed internationally. The design scheme of adjustable DC regulated power supply eliminates the bulky volume of traditional DC power supply due to the power frequency transformer.
Compared with traditional power supply, high-frequency DC power supply has the advantages of small size, light weight and high efficiency. At the same time, it also creates conditions for reducing the volume of high-power DC power supply. This power supply is also called high-frequency adjustable switching power supply.
The adjustable DC regulated power supply has complete protection functions, overvoltage and overcurrent points can be continuously set and predicted, and the output voltage can be controlled by touch switch.
General working principle of adjustable DC regulated power supply
When the input AC voltage of the parameter regulator is 150V-260V, the output voltage regulation effect is good at 220V. Below and above this range, its efficiency will decrease.
The first step of control is to use a single-chip microcomputer to adjust the input voltage below 310V and above 90V to 190V-250V, and then use a parameter voltage regulator to stabilize the voltage, which has a good effect.
The AC voltage input from the mains fluctuates greatly. After the interference voltage such as high-frequency pulses is filtered out by the overvoltage absorption filter circuit, it is sent to the DC switching voltage regulator, AC sampling circuit and control execution circuit.
The adjustable power supply has low power, but it can convert the 60-320V AC voltage into +5V, +12V, -12V DC voltage. The +5V voltage is supplied to the single-chip microcomputer, and the ±12V voltage is supplied to the high-power switch module of the control circuit.
The single-chip microcomputer analyzes and judges the input voltage data collected by the sampling circuit and sends a control signal to the trigger circuit to control and adjust the output voltage.
The control execution circuit consists of an SSR zero-crossing switch high-power module and a tapped autotransformer. The RC absorption circuit is used between the SSRs to absorb overvoltage and overcurrent, so that the SSR will not be damaged during switching.
The control execution circuit controls the input voltage of 90-310V to the range of 190V-240V, and then sends it to the parameter regulator for precise voltage regulation.
The parameter regulator is composed of an LC oscillator composed of an inductor and a capacitor, and the oscillation frequency is 50HZ. No matter how the mains power changes, its oscillation frequency will not change, so the output voltage will not change, and the voltage regulation accuracy is high.
Even if the input voltage waveform is greatly distorted, it is a standard sine wave after the oscillation output of the parameter regulator, so the adjustable power supply has strong anti-interference and purification capabilities.
Protection alarm circuit: When there is a situation that endangers the safety of the equipment, only an audible and visual alarm is issued to prompt the operator to take measures without cutting off the output voltage.
When there is no output voltage, the temperature of the control box is too high, the mains input is higher than 300V, and the mains input is lower than 130V, there will be an audible and visual alarm. When the input current is too large, the input (output) air automatic switch automatically jumps.
