Multi-section isolation type AC-DC direct current output circuit

Abstract

The utility model relates to the technical field of power supply control circuits, and provides a multi-segment isolation type AC-DC direct current output circuit comprising a filter circuit used for suppressing electromagnetic interference and ensuring the quality of an input alternating current power supply; the rectifying circuit is used for converting the alternating current into preliminarily stable direct current; the power supply circuit is used for providing starting and working voltage for the controller; the control circuit at least internally comprises a control chip U1 and is used for adjusting the final output voltage through an external signal; through the design of a multi-section isolation circuit, DC output of a plurality of electrical isolations is realized, loads are ensured not to interfere with each other, and the stability and safety of the system are improved. Meanwhile, the flexible multi-section voltage regulation circuit is combined with MCU control, the output voltage can be regulated in real time according to actual requirements, the requirements of diversified application scenes are met, and the application range and the flexibility of the power supply are remarkably enhanced.

Description

Technical Field

[0001] This utility model relates to the field of power supply control circuit technology, specifically a multi-segment isolated AC-DC output circuit. Background Technology

[0002] In modern power electronic devices, AC-DC converters are widely used in various applications, from consumer electronics to industrial control systems. With the diversification of application requirements and technological advancements, the market demand for power supply solutions that can provide multiple independent DC outputs with electrical isolation between them is increasing. This type of power supply not only needs to be highly efficient and stable, but also capable of flexibly adjusting the output voltage under different load conditions. Especially in applications such as cooling fans, industrial exhaust fans, and DC water pumps, the power supply must be able to adapt to different operating modes and speed controls to ensure the stability and efficiency of equipment operation.

[0003] However, current isolated AC-DC output circuits, due to their traditional design and single output, often cannot output at multiple speeds, resulting in unstable loads and causing faults such as motor speed control vibration and abnormal noise, discontinuous water pump flow, and fan resonance, thus limiting their application environment. Utility Model Content

[0004] The present invention aims to overcome the shortcomings of the prior art by providing a multi-segment isolated AC-DC output circuit with multi-terminal output control function to improve and broaden the application scenarios.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a multi-segment isolated AC-DC output circuit, comprising: a filter circuit for suppressing electromagnetic interference and ensuring the quality of the input AC power supply; a rectifier circuit for converting AC power into initially stable DC power; a power supply circuit for providing startup and operating voltage to the controller; a control circuit, which internally includes at least a control chip U1 for adjusting the final output voltage via an external signal; and an output circuit for realizing multiple electrically isolated DC outputs.

[0006] Furthermore, the rectifier circuit consists of a rectifier bridge DB1 and an electrolytic capacitor EC1. The positive output terminal of the rectifier bridge DB1 is connected to the positive terminal of the electrolytic capacitor EC1, and the negative output terminal is grounded. The negative terminal of the electrolytic capacitor EC1 is also grounded, thereby converting the AC voltage into a preliminarily stable DC voltage, ready to be sent to subsequent circuits for processing.

[0007] Furthermore, the filter circuit consists of common-mode inductors LF1 and LF2 and a safety capacitor CX1. One end of the common-mode inductor LF1 is connected to the AC input line L, and the other end is connected to one of the AC input terminals of the rectifier bridge DB1. One end of the common-mode inductor LF2 is connected to the AC input line N, and the other end is connected to the other AC input terminal of the rectifier bridge DB1. The safety capacitor CX1 is connected between LF1 and LF2 to form an EMC network to filter out high-frequency noise in the input AC power supply.

[0008] Furthermore, the power supply circuit includes the primary winding of a high-frequency transformer T1, a diode D2, a resistor R2, and an electrolytic capacitor EC3. One end of the primary winding of the high-frequency transformer T1 is connected to the positive output terminal of the rectifier bridge DB1, and the other end is connected to the power supply circuit through a series connection of diode D2 and resistor R2. The electrolytic capacitor EC3 is connected in parallel to the power supply circuit to stabilize the operating voltage of the U1 controller and ensure its normal operation.

[0009] Furthermore, the control circuit consists of an optocoupler OP1 and a feedback network FB-2.5. The input terminal of the optocoupler OP1 is connected to the feedback network FB-2.5, and the output terminal of the optocoupler OP1 is connected to the feedback pin of the voltage regulator chip U2 through a resistor R13 to adjust the operating state of U2. The feedback network FB-2.5 is composed of resistors R18, R19, R20, and R21. One end of each resistor is connected to different I / O pins Mode1-Mode4 of the microprocessor MCU, and the other end is connected to the input terminal of the optocoupler OP1. The capacitors C4 and C5 are connected in parallel between the feedback network FB-2.5 and ground to filter and smooth voltage fluctuations.

[0010] Furthermore, the output circuit includes the secondary winding of the high-frequency transformer T1, which is designed as a multi-winding circuit, with each winding corresponding to an independent DC output channel. The channels are electrically isolated to meet the needs of different loads.

[0011] Furthermore, the power supply circuit also includes a resistor R1, one end of which is connected to the high voltage input HV and the other end is connected to the power supply circuit to limit the current and protect the circuit. The power supply circuit has a diode D2 and a resistor R2 connected in series to provide the start-up voltage for the U1 controller.

[0012] Furthermore, the control circuit is not limited to using four control ports Mode1-Mode4; the number of control ports can be expanded by adding additional resistors and corresponding MCU I / O pins.

[0013] The advantages of this invention lie in its multi-segment isolation circuit design, which enables multiple electrically isolated DC outputs, ensuring that there is no interference between loads and improving system stability and safety. Simultaneously, the flexible multi-segment voltage regulation circuit, combined with MCU control, can adjust the output voltage in real time according to actual needs, meeting the requirements of diverse application scenarios and significantly enhancing the power supply's applicability and flexibility. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall circuit of this utility model.

[0015] Figure 1 In the diagram: 1-Rectifier circuit; 2-Filter circuit; 3-Power supply circuit; 4-Control circuit; 5-Output circuit. Detailed Implementation

[0016] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0017] The following disclosure provides many different embodiments or examples for implementing different structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, various specific examples of processes and materials are provided in this application, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0018] This application provides a multi-segment isolated AC-DC output circuit. This circuit achieves multiple electrically isolated DC outputs through multi-segment isolation design, ensuring no interference between loads and improving system stability and safety. Simultaneously, the flexible multi-segment voltage regulation circuit, combined with MCU control, can adjust the output voltage in real time according to actual needs, meeting the requirements of diverse application scenarios and significantly enhancing the power supply's applicability and flexibility. The following provides a detailed description of this multi-segment isolated AC-DC output circuit. It should be noted that the order of description of the following embodiments is not intended to limit the preferred order of the embodiments.

[0019] The present application will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0020] Please see Figure 1 This embodiment provides a multi-segment isolated AC-DC output circuit 5, comprising: a filter circuit 2 for suppressing electromagnetic interference and ensuring the quality of the input AC power supply; a rectifier circuit 1 for converting AC power into initially stable DC power; a power supply circuit 3 for providing startup and operating voltage to the controller; a control circuit 4, which internally includes at least a control chip U1 for adjusting the final output voltage via an external signal; and an output circuit 5 for realizing multiple electrically isolated DC outputs.

[0021] Furthermore, the rectifier circuit 1 consists of a rectifier bridge DB1 and an electrolytic capacitor EC1. The positive output terminal of the rectifier bridge DB1 is connected to the positive terminal of the electrolytic capacitor EC1, and the negative output terminal is grounded. The negative terminal of the electrolytic capacitor EC1 is also grounded, thereby converting the AC voltage into a preliminarily stable DC voltage, ready to be sent to subsequent circuits for processing. This design simplifies the power conversion process, and the electrolytic capacitor EC1 smooths the DC voltage and reduces voltage fluctuations, thus providing more stable operating conditions for subsequent circuits.

[0022] Furthermore, the filter circuit 2 consists of common-mode inductors LF1 and LF2 and a safety capacitor CX1, wherein: one end of the common-mode inductor LF1 is connected to the AC input L line and the other end is connected to one of the AC input terminals of the rectifier bridge DB1; one end of the common-mode inductor LF2 is connected to the AC input N line and the other end is connected to the other AC input terminal of the rectifier bridge DB1; and the safety capacitor CX1 is connected across LF1 and LF2 to form an EMC network to filter out high-frequency noise in the input AC power supply.

[0023] During operation, the EMC network composed of common-mode inductors LF1 and LF2 and safety capacitor CX1 can effectively reduce electromagnetic interference on AC power lines, protect subsequent circuits from external noise, and prevent internally generated noise from being conducted into the power grid.

[0024] Furthermore, the power supply circuit 3 includes the primary winding of a high-frequency transformer T1, a diode D2, a resistor R2, and an electrolytic capacitor EC3. One end of the primary winding of the high-frequency transformer T1 is connected to the positive output terminal of the rectifier bridge DB1, and the other end is connected to the power supply circuit 3 through a series connection of diode D2 and resistor R2. The electrolytic capacitor EC3 is connected in parallel to the power supply circuit 3 to stabilize the operating voltage of the U1 controller and ensure its normal operation. Through the above process, a stable power supply voltage can be provided to ensure that the control chip U1 can obtain an appropriate operating voltage under various operating conditions, thereby enhancing the reliability and efficiency of the system.

[0025] Furthermore, the control circuit 4 consists of an optocoupler OP1 and a feedback network FB-2.5. The input of the optocoupler OP1 is connected to the feedback network FB-2.5, and the output of the optocoupler OP1 is connected to the feedback pin of the voltage regulator chip U2 via resistor R13 to adjust the operating state of U2. The feedback network FB-2.5 is composed of resistors R18, R19, R20, and R21. One end of each resistor is connected to different I / O pins Mode1-Mode4 of the microprocessor MCU, and the other end is connected to the input of the optocoupler OP1. Capacitors C4 and C5 are connected in parallel between the feedback network FB-2.5 and ground to filter and smooth voltage fluctuations. In use, the combination of the optocoupler OP1 and the feedback network FB-2.5 achieves... Electrical isolation ensures no direct electrical connection between the control system and the main power stage, improving safety and reducing mutual interference. Simultaneously, by adjusting the states of different I / O pins (Mode1-Mode4) of the MCU, the final output voltage can be flexibly changed to adapt to different application scenarios. Capacitors C4 and C5 further filter out high-frequency components in the feedback signal, ensuring its purity and contributing to improved output voltage accuracy and stability. Control ports Mode1-Mode4 are connected to network FB-2.5 via resistors R18-R21. Changing the current through R16 alters the equivalent on-state resistance of optocoupler OP1, feeding back to the high-voltage side FB. Control chip U1 detects and adjusts the PWM output duty cycle to achieve effective voltage regulation.

[0026] Furthermore, the output circuit 5 includes the secondary winding of the high-frequency transformer T1, which is designed as a multi-winding circuit. Each winding corresponds to an independent DC output channel, and the channels are electrically isolated to meet the needs of different loads. During operation, the design of the secondary winding of the high-frequency transformer T1 as a multi-winding circuit, with each winding corresponding to an independent DC output channel and the channels electrically isolated, can meet the needs of multiple loads for different voltage levels, while also avoiding mutual interference between the outputs.

[0027] Furthermore, the power supply circuit 3 also includes a resistor R1. One end of the resistor R1 is connected to the high-voltage input HV, and the other end is connected to the power supply circuit 3. It is used to limit the current and protect the circuit. The power supply circuit 3 has a diode D2 and a resistor R2 connected in series to provide a startup voltage for the U1 controller to limit the current and protect the circuit. By connecting one end of the resistor R1 to the high-voltage input HV and the other end to the power supply circuit 3, the main function of this resistor is to limit the current flowing into the power supply circuit 3. During power-on or transient voltage spikes, R1 can effectively prevent excessive current from directly impacting subsequent circuit components, thereby playing a protective role.

[0028] Furthermore, the control circuit 4 is not limited to using four control ports (Mode1-Mode4). The number of control ports can be expanded by adding additional resistors and corresponding MCU I / O pins. This design, which is not limited to four control ports, allows the system to add more control options according to actual needs, and expand the number of control ports by adding additional resistors and corresponding MCU I / O pins. This flexibility makes the circuit solution suitable for a wider variety of applications.

[0029] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0030] The above provides a detailed description of a multi-segment isolated AC-DC output circuit provided in the embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the technical solutions and core ideas of this application. Those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A multi-section isolated AC-DC DC output circuit, characterized by, Comprise: Filter circuit (2) for suppressing electromagnetic interference, ensuring the quality of the input AC power supply; Rectifier circuit (1) for converting AC to preliminary stable DC; Power supply circuit (3) for providing start-up and working voltage for the controller; Control circuit (4) containing at least control chip U1 inside, for adjusting the final output voltage through external signals; And Output circuit (5) for realizing multiple electrically isolated DC outputs.

2. The multi-section isolated AC-DC DC output circuit of claim 1, wherein, The rectifier circuit (1) is composed of rectifier bridge DB1 and electrolytic capacitor EC1, wherein the positive output end of the rectifier bridge DB1 is connected to the positive electrode of the electrolytic capacitor EC1, the negative output end is grounded, and the negative electrode of the electrolytic capacitor EC1 is also grounded, thereby converting AC voltage into preliminary stable DC voltage, ready for subsequent circuit processing.

3. The multi-section isolated AC-DC DC output circuit of claim 2, wherein, The filter circuit (2) is composed of common mode inductors LF1, LF2 and safety capacitor CX1, wherein one end of the common mode inductor LF1 is connected to the AC input L line, the other end is connected to one of the AC input ends of the rectifier bridge DB1, one end of the common mode inductor LF2 is connected to the AC input N line, the other end is connected to the other AC input end of the rectifier bridge DB1, and the safety capacitor CX1 is connected across LF1 and LF2 to form an EMC network to filter out high-frequency noise in the input AC power supply.

4. The multi-section isolated AC-DC DC output circuit of claim 2, wherein, The power supply circuit (3) contains the primary winding of high-frequency transformer T1, diode D2, resistor R2 and electrolytic capacitor EC3, wherein one end of the primary winding of high-frequency transformer T1 is connected to the positive output end of rectifier bridge DB1, the other end is connected to the power supply circuit (3) through the series connection of diode D2 and resistor R2, and the electrolytic capacitor EC3 is connected in parallel to the power supply circuit (3) to stabilize the working voltage of U1 controller and ensure its normal operation.

5. The multi-section isolated AC-DC DC output circuit of claim 4, wherein, The control circuit (4) is composed of optocoupler OP1 and feedback network FB-2.5, wherein the input end of the optocoupler OP1 is connected to the feedback network FB-2.5, the output end of the optocoupler OP1 is connected to the feedback pin of voltage stabilizing chip U2 through resistor R13, for adjusting the working state of U2, the feedback network FB-2.5 is composed of resistors R18, R19, R20 and R21, one end of each resistor is respectively connected to different I / O pins Mode1-Mode4 of microprocessor MCU, the other end is commonly connected to the input end of optocoupler OP1, and capacitors C4 and C5 are connected in parallel between feedback network FB-2.5 and ground for filtering and smoothing voltage fluctuations.

6. The multi-section isolated AC-DC DC output circuit of claim 4, wherein, The output circuit (5) includes the secondary winding of high-frequency transformer T1, which is designed in a multi-winding form, each winding corresponds to an independent DC output channel, and the channels are electrically isolated to meet the needs of different loads.

7. The multi-section isolated AC-DC DC output circuit of claim 4, wherein, The power supply circuit (3) further comprises a resistor R1, one end of which is connected to a high-voltage input HV, and the other end of which is connected to the power supply circuit (3), for limiting current and protecting the circuit, and the power supply circuit (3) is connected in series with a diode D2 and a resistor R2, for providing a starting voltage for the U1 controller.

8. The multi-section isolated AC-DC DC output circuit of claim 4, wherein, The control circuit (4) is not limited to four control ports Mode1-Mode4, and the number of control ports can be expanded by additionally adding resistors and corresponding MCU I / O pins.

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