Device and method for suppressing power surge current

Abstract

The invention provides a power supply surge current suppression device and method, comprising: a power supply, a surge control circuit and a voltage detection module; the surge control circuit includes: a capacitor, a discharge diode, a charging diode, a MOS tube and an inductor; The positive end of the power supply is connected to the input end of the capacitor; the capacitor is connected with the discharge diode to form a discharge circuit, the capacitor is connected with the charging diode and the inductor in sequence to form a charging circuit, and the capacitor is connected with the MOS tube to form a current suppression circuit; the The voltage detection module is respectively connected with the output end of the capacitor and the G pole of the MOS tube; the voltage detection module is used to realize the surge current suppression function by using the zero-voltage switching of the MOS tube. By accurately judging the switching point of the surge current, the invention greatly reduces the hardware design, saves the cost and can effectively solve the possible damage caused by the surge current.

Description

technical field [0001] The invention belongs to the technical field of power supply protection, and in particular relates to a power supply surge current suppressing device and method. Background technique [0002] Usually when the power supply starts, due to the capacitance in the circuit, a large peak current is often caused. This current is called inrush current. If the inrush current is not suppressed, it will usually generate hundreds or even thousands of amperes. Current, such a large current will cause a transient drop in the input voltage, which will seriously reduce the life of the components or damage them. [0003] Most of the existing methods for suppressing inrush current are to use a thermistor in series with the main circuit to suppress the occurrence of inrush current. like figure 1 As shown, when the switching power supply starts, the negative temperature coefficient thermistor current limiting resistor is at normal temperature, and its own resistance is h...

AI Technical Summary

Problems solved by technology

[0004] Since the thermistor is connected in series in the main circuit, whether it is the surge current when the machine is just turned on or the working current during normal operation, it will flow through the thermistor, resulting in the loss of power supply.

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