Dc power supply composition and detection

First, power transformer

The AC power provided by the power grid is 220V (or 380V). The amplitude of DC voltage required by various electronic devices varies. Therefore, it is often necessary to pass near the power grid voltage through the power supply transformer, and then to rectify, filter and regulate the secondary side voltage after the transformation, and then get the required DC voltage amplitude.

Two, rectifier circuit

The function of DC power supply rectifier circuit is to convert sinusoidal alternating voltage into unidirectional pulsating voltage by using the rectifier element with unidirectional conductivity. However, the unidirectional pulsating voltage often contains a large pulsating component, and the adjustable DC power supply is far from the ideal DC voltage.

3. Filter

The filter circuit is mainly composed of capacitor, inductor and other energy storage components. The main function of this circuit is to filter out the AC component of the unidirectional pulsating voltage as much as possible, so that the output voltage becomes a relatively smooth DC voltage. However, when the power grid voltage or load current changes, the amplitude of the filter DC voltage will also change, high-power DC power inverter, in the relatively high requirements of the electronic equipment, this situation is not in line with the requirements.

Four, voltage regulator circuit

The role of the voltage regulator circuit in the DC power supply is to take certain measures to aging the high-power DC power supply, so that the output DC voltage in the grid voltage or load current changes to maintain stability.

For DC power supply fault detection, we can sum up as "two requirements". Learn to repair faults to "learn, practice, think". "Learning" is to learn theoretical knowledge, repair should be based on theory, not blindly engaged in, "practice" is to combine theory with practice. Practice more. Practice more. "Thinking" is to analyze more, summarize more, accumulate experience and improve the level in practice. "Learning, practice and thinking" is the foundation, and the three complement each other. In a word, only on the basis of theoretical knowledge and practical operation can we continuously improve in this aspect.

Dc power to judge the simple fault to "ask, see, touch".

"Ask" is to understand the causes and consequences of DC power failure, such as "the wrench fell to the ground holding a" open the power switch on..." ; "See" is to view the appearance and internal components of the circuit, to see whether the occurrence of line breaking, loosening, burning, rupture and other abnormal phenomena; To "touch" is to use a screw or other tool to touch a circuit element. First in the case of no power, see whether the DC power supply components loose, poor contact, virtual welding. Then in the case of DC power supply, touch whether the component overheating. In a word, "ask, look, touch" is an investigation and research. Through these simple comprehensive judgments, about general faults are found.