Power supply circuit and power supply equipment

Abstract

The invention relates to the field of electronic circuits, and discloses a power supply circuit and power supply equipment. The power supply circuit comprises an energy storage inductor, a first switch tube, a second switch tube, a current transformer and a sampling processing circuit, wherein the current transformer comprises a first primary winding, a second primary winding and a secondary winding, the first primary winding and the first switch tube are connected in series to form a first current loop of the energy storage inductor, the second primary winding and the second switching tube are connected in series to form a second current loop of the energy storage inductor, the first current flowing through the first primary winding and the second current flowing through the second primary winding are alternately carried out in a preset switching period so as to realize the magnetic flux resetting of the current transformer, and the sampling processing circuit obtains information of the first current flowing through the first primary winding and information of the second current flowing through the second primary winding through the secondary winding. Therefore, through the mode, the working reliability of the system can be ensured without adding an additional reset circuit, and meanwhile, the precision of the sampling current can be improved.

Description

technical field [0001] The invention relates to the technical field of electronic circuits, in particular to a power supply circuit and power supply equipment. Background technique [0002] The current transformer is a device based on the principle of electromagnetic induction. The current transformer includes a primary winding and a secondary winding. When the primary winding of the current transformer has current flowing through it, the secondary winding of the current transformer will induce a current. With this characteristic, transformers are widely used in current isolation sampling. However, the current current transformer can only work in a single quadrant, that is, it can only excite in one direction, so the current information obtained by sampling can only reflect the zero-crossing moment of the current, and, because the current transformer works in a single quadrant, If no additional reset circuit is added, the current transformer will have the risk of magnetic s...

AI Technical Summary

Problems solved by technology

However, the current current transformer can only work in a single quadrant, that is, it can only excite in one direction, so the current information obtained by sampling can only reflect the zero-crossing moment of the current, and, because the current transformer works in a single quadrant, If no additional reset circuit is added, the current transformer will have the risk of magnetic saturation, which will greatly reduce the reliability of the system and the sampling accuracy of the current, and the circuit structure will become complicated if the reset circuit is added.

Images