High-power switching power supply

Abstract

The utility model relates to the technical field of switching circuits, in particular to a high-power switching power supply. According to the switching power supply, the H-shaped inductor is additionally arranged in the rectifying and filtering unit to improve harmonic current, the application of a PFC module circuit is omitted, meanwhile, the winding directions of part of inductive components are changed, so that the directions of magnetic force generated by the inductive components when the power supply is powered on are the same, the voltage anti-interference capability of the power supply is improved, and the reliability of the power supply is improved. According to the high-power switching power supply provided by the utility model, the hardware cost is reduced while the miniaturization structure of the power supply is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of switch circuits, in particular to a high-power switch power supply. Background Art

[0002] In related technologies, the power threshold for a switching power supply to have PFC (Power Factor Correction) is 75W. Switching power supplies without a PFC module generally require the addition of a PFC circuit module when the power exceeds the threshold in order to meet EMI harmonic current test standards. However, its main disadvantage is the complex circuit design, which increases manufacturing costs.

[0003] In addition, the design and implementation of active PFC circuits require higher technical requirements and more complex components, which further increases costs.

[0004] Although active PFC circuits can significantly increase power factor and improve electromagnetic compatibility, their high cost and complexity may not be acceptable in some applications, especially in cost-sensitive applications.

[0005] Therefore, it is particularly important to design low-cost switching power supply products within a certain power range. Utility Model Content

[0006] The utility model aims to provide a high-power switching power supply which does not require a PFC module circuit structure.

[0007] Specifically, the utility model provides a high-power switching power supply, including an electromagnetic filtering unit, a first rectifying and filtering unit, a voltage-current switching unit, a second rectifying and filtering unit, and a first power output unit, wherein:

[0008] The electromagnetic filter unit is used to connect to an external AC power supply, wherein a first end of the electromagnetic filter unit is connected to a neutral line, and a second end of the electromagnetic filter unit is connected to a live line;

[0009] The first rectification and filtering unit includes a first voltage conversion circuit, a second voltage conversion circuit, a first capacitor, a first resistor, a second resistor, a third resistor, and a fourth resistor, wherein:

[0010] The first input end of the first transformer circuit is connected to the first end of the electromagnetic filter unit, the second input end of the first transformer circuit is connected to the sensitive resistor and then to the second end of the electromagnetic filter unit, the first output end of the first transformer circuit is connected to the first input end of the second transformer circuit, and the second end of the first transformer circuit is connected to the second input end of the second transformer circuit;

[0011] The first end and the second end of the first capacitor are connected to the first output end and the second output end of the first voltage conversion circuit respectively;

[0012] A first end of the first resistor is connected to a first output end of the first voltage conversion circuit, a second end of the first resistor is connected to a first end of the second resistor, and a second end of the second resistor is connected to a second output end of the first voltage conversion circuit;

[0013] A first end of the third resistor is connected to the first input end of the second voltage conversion circuit, a second end of the third resistor is connected to the first end of the fourth resistor, and a second end of the fourth resistor is connected to the second input end of the second voltage conversion circuit;

[0014] The first input end of the voltage-current switching unit is connected to the first output end of the second voltage conversion circuit, and the second input end of the voltage-current switching unit is connected to the second output end of the second voltage conversion circuit;

[0015] The second rectifying and filtering unit includes a second capacitor and a first electrolytic capacitor, a first end of the second capacitor is connected to the first output end of the voltage-current switching unit, a second end of the second capacitor is connected to the second output end of the voltage-current switching unit, and is grounded at the same time;

[0016] The positive terminal of the first electrolytic capacitor is connected to the first output terminal of the voltage-current switching unit, and the negative terminal of the first electrolytic capacitor is connected to the second output terminal of the voltage-current switching unit;

[0017] The first power output unit is connected to the positive terminal of the first electrolytic capacitor and outputs high-voltage direct current to the outside.

[0018] Furthermore, the second rectifying and filtering unit further includes a first I-shaped inductor, a fifth resistor, a third capacitor and a second electrolytic capacitor, wherein:

[0019] The fifth resistor is arranged in series between the positive terminal of the first electrolytic capacitor and the first power output unit;

[0020] The first end of the first I-shaped inductor is connected to the first end of the fifth resistor, and the second end of the first I-shaped inductor is connected to the second end of the fifth resistor;

[0021] The first end of the third capacitor is connected to the second end of the fifth resistor, and the second end of the third capacitor is connected to the negative terminal of the first electrolytic capacitor;

[0022] The positive terminal of the second electrolytic capacitor is connected to the first terminal of the third capacitor, and the negative terminal of the second electrolytic capacitor is connected to the second terminal of the third capacitor.

[0023] Further, the first rectification filter unit further comprises a second I-shaped inductor, a sixth resistor, a fourth capacitor and a third I-shaped inductor, wherein:

[0024] The second I-shaped inductor is arranged in series between the second output end of the second voltage conversion circuit and the second input end of the voltage-current switching unit.

[0025] The first end of the sixth resistor is connected to the first end of the second I-shaped inductor, and the second end of the sixth resistor is connected to the second end of the second I-shaped inductor.

[0026] The first end and the second end of the fourth capacitor are respectively connected to the first input end and the second input end of the voltage-current switching unit.

[0027] The third I-shaped inductor is arranged in series between the first output end of the first voltage conversion circuit and the first input end of the second voltage conversion circuit.

[0028] Further, the first rectification filter unit further comprises a thermistor arranged in series between the thermistor and the second input end of the first voltage conversion circuit.

[0029] Further, the high-power switching power supply further comprises a second power output unit connected to the first output end of the voltage-current switching unit and outputting high-voltage direct current.

[0030] Further, the inductance of the first I-shaped inductor is 20-50uH.

[0031] Further, the second I-shaped inductor has the same magnetic field direction as the second voltage conversion circuit.

[0032] The high-power switching power supply provided by the utility model has the advantages that the high-power switching power supply does not need a PFC module circuit structure, the rectification filter unit is provided with an I-shaped inductor to improve harmonic current, the application of the PFC module circuit is omitted, meanwhile, the winding directions of some inductive components are changed, the magnetic force directions of the inductive components generated during power supply energization are the same, the power supply voltage anti-interference capability is improved, the high-power switching power supply provided by the utility model has the power supply miniaturization structure and reduces the hardware cost. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is a circuit structure schematic view of the high-power switching power supply provided by the utility model;

[0034] Figure 2 is a circuit structure schematic view of another high-power switching power supply provided by the utility model;

[0035] Figure 3 This is a schematic diagram of the EMI conduction test results of the inductive components provided by the present invention. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0037] Please refer to Figure 1 , Figure 1 : This is a circuit diagram of a high-power switching power supply provided by the present invention. The high-power switching power supply 100 includes an electromagnetic filtering unit 101, a first rectifying and filtering unit 102, a voltage-current switching unit 103 (BD), a second rectifying and filtering unit 104, and a first power output unit 105, wherein:

[0038] The electromagnetic filter unit 101 is used to connect to an external AC power supply (CN INPUT), wherein a first end of the electromagnetic filter unit 101 is connected to a neutral line N, and a second end of the electromagnetic filter unit is connected to a live line L;

[0039] The first rectifying and filtering unit 102 includes a first voltage transformation circuit LF1, a second voltage transformation circuit LF2, a first capacitor C1, a first resistor R1, a second resistor R2, a third resistor R3 and a fourth resistor R4, wherein:

[0040] A first input end of the first transformer circuit LF1 is connected to a first end of the electromagnetic filter unit 101, a second input end of the first transformer circuit LF1 is connected to a sensitive resistor FUSE and then to a second end of the electromagnetic filter unit 101, a first output end of the first transformer circuit LF1 is connected to a first input end of the second transformer circuit LF2, and a second end of the first transformer circuit LF1 is connected to a second input end of the second transformer circuit LF2;

[0041] The first end and the second end of the first capacitor C1 are connected to the first output end and the second output end of the first voltage transformation circuit LF1 respectively;

[0042] A first end of the first resistor R1 is connected to a first output end of the first voltage transformation circuit LF1, a second end of the first resistor R1 is connected to a first end of the second resistor R2, and a second end of the second resistor R2 is connected to a second output end of the first voltage transformation circuit LF1;

[0043] A first end of the third resistor R3 is connected to the first input end of the second voltage conversion circuit LF2, a second end of the third resistor R3 is connected to the first end of the fourth resistor R4, and a second end of the fourth resistor R4 is connected to the second input end of the second voltage conversion circuit LF2;

[0044] The first input terminal of the voltage-current switching unit 103 is connected to the first output terminal of the second voltage transformation circuit LF2, and the second input terminal of the voltage-current switching unit 103 is connected to the second output terminal of the second voltage transformation circuit LF2. In the embodiment of the present invention, the voltage-current switching unit 103 is implemented using a 2A1000VDIP4 rectifier chip.

[0045] The second rectifying and filtering unit 104 includes a second capacitor C2 and a first electrolytic capacitor EC1, wherein a first end of the second capacitor C2 is connected to the first output end of the voltage-current switching unit 103, and a second end of the second capacitor C2 is connected to the second output end of the voltage-current switching unit 103 and is grounded.

[0046] The positive terminal of the first electrolytic capacitor EC1 is connected to the first output terminal of the voltage-current switching unit 103, and the negative terminal of the first electrolytic capacitor EC1 is connected to the second output terminal of the voltage-current switching unit 103;

[0047] The first power output unit 105 is connected to the positive terminal of the first electrolytic capacitor EC1 and outputs a high-voltage direct current (HV-DC OUTPUT1) to the outside.

[0048] For details, please refer to Figure 2 , Figure 2 This is a schematic diagram of the circuit structure of another high-power switching power supply provided by the present invention. In the embodiment of the present invention, Figure 1 The high-power switching power supply 100 shown is suitable for 40W power scenarios. In order to achieve high-power application scenarios, the present invention Figure 1 The circuit structure shown has been further improved. Specifically, for the 75-120W power scenario:

[0049] The second rectifying and filtering unit 104 further includes a first I-shaped inductor L1, a fifth resistor R5, a third capacitor C3, and a second electrolytic capacitor EC2, wherein:

[0050] The fifth resistor R5 is connected in series between the positive terminal of the first electrolytic capacitor EC1 and the first power output unit 105;

[0051] A first end of the first I-shaped inductor L1 is connected to a first end of the fifth resistor R5, and a second end of the first I-shaped inductor L1 is connected to a second end of the fifth resistor R5;

[0052] A first end of the third capacitor C3 is connected to the second end of the fifth resistor R5, and a second end of the third capacitor C3 is connected to the negative terminal of the first electrolytic capacitor EC1;

[0053] The positive terminal of the second electrolytic capacitor EC2 is connected to the first terminal of the third capacitor C3, and the negative terminal of the second electrolytic capacitor EC2 is connected to the second terminal of the third capacitor C3.

[0054] The inductance of the first I-shaped inductor L1 is 20-50uH (microhenries). In this embodiment of the utility model, the I-shaped inductor itself acts as a choke and differential mode inductor in the power supply circuit. In this way, the I-shaped inductor can prevent harmonic current components in the power supply from polluting the environment and also prevent harmonic current components in the power supply from affecting the power supply itself, thereby achieving a stable power output effect.

[0055] Specifically, for a power scenario of 120W-150W, the first rectifying and filtering unit 102 further includes a second I-shaped inductor L2, a sixth resistor R6, a fourth capacitor C4, and a third I-shaped inductor L3, wherein:

[0056] The second I-shaped inductor L2 is arranged in series between the second output terminal of the second voltage transformation circuit LF2 and the second input terminal of the voltage-current switching unit 103;

[0057] A first end of the sixth resistor R6 is connected to a first end of the second I-shaped inductor L2, and a second end of the sixth resistor R6 is connected to a second end of the second I-shaped inductor L2;

[0058] The first end and the second end of the fourth capacitor C4 are connected to the first input end and the second input end of the voltage-current switching unit 103 respectively;

[0059] The third I-shaped inductor L3 is arranged in series between the first output end of the first transformation circuit LF1 and the first input end of the second transformation circuit LF2.

[0060] The magnetic fields generated by the second I-shaped inductor L2 and the second transformer circuit LF2 have the same direction. The EMI (Electromagnetic Interference) conduction test results of the embodiment of the present invention on the magnetic fields generated by different winding methods of the second I-shaped inductor L2 and the second transformer circuit LF2 are as follows: Figure 3 As shown, Figure 3 The left side shows the EMI conduction result when the magnetic field directions of the second I-shaped inductor L2 and the second transformer circuit LF2 are opposite. Figure 3The right side shows the EMI conduction result when the magnetic field directions of the second I-shaped inductor L2 and the second transformer circuit LF2 are the same.

[0061] It can be seen that when low voltage is input, the current becomes larger, and the right-hand spiral is determined. When the magnetic forces generated by the second I-shaped inductor L2 and the common-mode inductor in the second transformer circuit LF2 are in opposite directions and the two inductors are very close, the inductance of the two inductors is large, so the magnetic field intensity is large, and the magnetic fields of the two inductors cancel each other out, thereby affecting the effect of the second I-shaped inductor L2 in filtering out differential-mode signals, and also affecting the effect of the second transformer circuit LF2 in filtering out common-mode signals, resulting in poor anti-interference ability of the power supply; therefore, in an embodiment of the present invention, the winding method of the second I-shaped inductor L2 and the inductor in the second transformer circuit LF2 is designed so that the magnetic fields generated by them are in the same direction, thereby improving the anti-interference ability of the power supply voltage, improving the EMI conduction test, and achieving the goal of miniaturization.

[0062] Preferably, the first rectifying and filtering unit 101 further includes a thermistor NTC, and the thermistor NTC is connected in series between the resistor FUSE and the second input end of the first voltage conversion circuit LF1.

[0063] The high-power switching power supply 100 further includes a second power output unit 106 , which is connected to the first output terminal of the voltage-current switching unit 103 and outputs a high-voltage direct current (HV-DC OUTPUT2 ) to the outside.

[0064] The beneficial effect achieved by the present invention is that a high-power switching power supply that does not require a PFC module circuit structure is proposed. The switching power supply improves harmonic current by adding an I-shaped inductor in the rectifier and filter unit, eliminating the use of the PFC module circuit. At the same time, by changing the winding direction of some inductive components, the magnetic forces generated by the inductive components when the power supply is energized are made in the same direction, thereby improving the power supply voltage anti-interference ability. The high-power switching power supply of the present invention achieves a miniaturized power supply structure while reducing hardware costs.

[0065] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0066] The embodiments of the present invention are described above in conjunction with the accompanying drawings. What is disclosed is only a preferred embodiment of the present invention. However, the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms and equivalent changes without departing from the scope of protection of the purpose of the present invention and the claims, which are all within the protection of the present invention.

Claims

1. A high-power switching power supply, characterized in that: It includes an electromagnetic filtering unit, a first rectifying and filtering unit, a voltage and current switching unit, a second rectifying and filtering unit and a first power output unit, wherein: The electromagnetic filter unit is used to connect to an external AC power supply, wherein a first end of the electromagnetic filter unit is connected to a neutral line, and a second end of the electromagnetic filter unit is connected to a live line; The first rectification and filtering unit includes a first voltage conversion circuit, a second voltage conversion circuit, a first capacitor, a first resistor, a second resistor, a third resistor, and a fourth resistor, wherein: The first input end of the first transformer circuit is connected to the first end of the electromagnetic filter unit, the second input end of the first transformer circuit is connected to the sensitive resistor and then to the second end of the electromagnetic filter unit, the first output end of the first transformer circuit is connected to the first input end of the second transformer circuit, and the second end of the first transformer circuit is connected to the second input end of the second transformer circuit; The first end and the second end of the first capacitor are connected to the first output end and the second output end of the first voltage conversion circuit respectively; A first end of the first resistor is connected to a first output end of the first voltage conversion circuit, a second end of the first resistor is connected to a first end of the second resistor, and a second end of the second resistor is connected to a second output end of the first voltage conversion circuit; A first end of the third resistor is connected to the first input end of the second voltage conversion circuit, a second end of the third resistor is connected to the first end of the fourth resistor, and a second end of the fourth resistor is connected to the second input end of the second voltage conversion circuit; The first input end of the voltage-current switching unit is connected to the first output end of the second voltage conversion circuit, and the second input end of the voltage-current switching unit is connected to the second output end of the second voltage conversion circuit; The second rectifying and filtering unit includes a second capacitor and a first electrolytic capacitor, a first end of the second capacitor is connected to the first output end of the voltage-current switching unit, a second end of the second capacitor is connected to the second output end of the voltage-current switching unit, and is grounded at the same time; The positive terminal of the first electrolytic capacitor is connected to the first output terminal of the voltage-current switching unit, and the negative terminal of the first electrolytic capacitor is connected to the second output terminal of the voltage-current switching unit; The first power output unit is connected to the positive terminal of the first electrolytic capacitor and outputs high-voltage direct current to the outside.

2. The high-power switching power supply according to claim 1, characterized in that: The second rectifying and filtering unit further includes a first I-shaped inductor, a fifth resistor, a third capacitor and a second electrolytic capacitor, wherein: The fifth resistor is arranged in series between the positive terminal of the first electrolytic capacitor and the first power output unit; The first end of the first I-shaped inductor is connected to the first end of the fifth resistor, and the second end of the first I-shaped inductor is connected to the second end of the fifth resistor; The first end of the third capacitor is connected to the second end of the fifth resistor, and the second end of the third capacitor is connected to the negative terminal of the first electrolytic capacitor; The positive terminal of the second electrolytic capacitor is connected to the first terminal of the third capacitor, and the negative terminal of the second electrolytic capacitor is connected to the second terminal of the third capacitor.

3. The high-power switching power supply according to claim 2, characterized in that: The first rectifying and filtering unit further includes a second I-shaped inductor, a sixth resistor, a fourth capacitor and a third I-shaped inductor, wherein: The second I-shaped inductor is arranged in series between the second output end of the second voltage conversion circuit and the second input end of the voltage-current switching unit; The first end of the sixth resistor is connected to the first end of the second I-shaped inductor, and the second end of the sixth resistor is connected to the second end of the second I-shaped inductor; The first end and the second end of the fourth capacitor are connected to the first input end and the second input end of the voltage-current switching unit respectively; The third I-shaped inductor is arranged in series between the first output end of the first transformer circuit and the first input end of the second transformer circuit.

4. The high-power switching power supply according to claim 1, characterized in that: The first rectifying and filtering unit further includes a thermistor, which is arranged in series between the inductor and the second input end of the first voltage conversion circuit.

5. The high-power switching power supply according to claim 3, characterized in that: The high-power switching power supply further includes a second power output unit, which is connected to the first output terminal of the voltage-current switching unit and outputs high-voltage direct current to the outside.

6. The high-power switching power supply according to claim 2, characterized in that: The inductance of the first I-shaped inductor is 20-50uH.

7. The high-power switching power supply according to claim 3, characterized in that: The magnetic fields generated by the second I-shaped inductor and the second transformer circuit have the same direction.

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