Switch power supply circuit

Abstract

The invention discloses a switch power supply circuit. The switch power supply circuit comprises a protection circuit, an input filtering circuit, a rectification filtering circuit, a main power switch tube circuit, an isolation voltage reduction circuit and an output rectification filtering circuit which are connected in sequence, wherein the output end of the output rectification filtering circuit forms a voltage negative feedback loop through an isolation negative feedback circuit, a control switch, the main power switch tube circuit and the isolation voltage reduction circuit which are connected in sequence. By adopting the switch power supply circuit, an alternative-current power supply of a power grid can be turned into direct-current power which is output stably to supply power to electric appliances such as an electric pump; in addition, as the output end of the output rectification filtering circuit forms the voltage negative feedback loop through the isolation negative feedback circuit, the control switch, the main power switch tube circuit and the isolation voltage reduction circuit which are connected in sequence, not only are high-frequency interference signals in an input power supply filtered off, but also the voltage of the output direct-current power can be stabilized through the voltage negative feedback loop, the control circuit has functions of short circuitprotection, over-current protection and power fail protection, and the security of a power supply can be ensured.

Description

technical field [0001] The invention belongs to the technical field of circuit control, and in particular relates to a switching power supply circuit. Background technique [0002] Electric pumps are all kinds of pumps driven by electricity to transport various liquid media, such as water pumps, oil pumps, concrete pumps, etc., and are often used in daily work and life. However, most of the current electric pumps have a single power supply module and can only be powered by alternating current or direct current, which is not convenient enough to use and affects work efficiency. [0003] The existing AC-to-DC switching power supply circuits generally have the following defects: when the input power is doped with interfering electromagnetic waves, the power circuit has poor anti-interference and cannot output DC stably, and when there is a lightning strike to generate high voltage or a short circuit to generate overcurrent When it is too large, it is easy to burn out the motor...

AI Technical Summary

Problems solved by technology

However, most of the current electric pumps have a single power supply module and can only be powered by AC or DC, which is not convenient enough to use and affects work efficiency.

[0003] The existing AC-to-DC switching power supply circuits generally have the following defects: when the input power is doped with interfering electromagnetic waves, the power circuit has poor anti-interference performance, and cannot output DC stably, and when there is a lightning strike, high voltage or short circuit produces overcurrent. When it is too large, it is easy to burn out the motor and cause potential safety hazards

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