MPPT flyback auxiliary source high-low voltage input power supply activation switching power supply circuit

Abstract

The invention discloses an MPPT (Maximum Power Point Tracking) flyback auxiliary source high-low voltage input power supply activation switching power supply circuit, which comprises a direct current input end used for receiving MPPT direct current power supply input; the input end of the primary auxiliary source input high-low voltage power supply activation switching power supply circuit is connected with the direct current input end, and the output end of the primary auxiliary source input high-low voltage power supply activation switching power supply circuit is connected with the flyback basic topology primary absorption circuit and used for automatically activating power supply in different input voltage ranges. Automatic switching, isolation and stable power supply are realized through the R7, the R8, the C1, the ZD1, the OP1, the Q1 and the D2, and 12V-150V input is compatible. The problem that R1-R6 continuously emits heat and is burnt out within the range of 60V-150V after 12V-60V stable activation power supply is avoided, and the static loss is reduced. After the work of the IC is activated and stabilized, the OP1 optocoupler controls the Q1 PMOS tube to cut off power supply, overheating of the R1-R6 is prevented, a common 1206 chip resistor can be used, a high-power cement resistor is not needed, materials and PCB space are saved, and automatic switching and isolation of high-voltage input and low-voltage input are achieved.

Description

Technical Field

[0001] The invention relates to a power supply circuit, in particular to an MPPT flyback auxiliary source high-low voltage input power supply activation switching power supply circuit. Background Art

[0002] In order to supply power to the high and low voltage input of the MPPT flyback auxiliary source, it can be compatible with the DC input voltage of 12V-150V and can start working normally. The starting resistor is not easy to match the corresponding resistance value in the wide range of 12V-150V voltage input, and it is incompatible with the control of the activation voltage and the large heat generation. It is necessary to use multiple starting resistors and match the circuit control to make the circuit complicated or use high-power cement resistors to implement it, resulting in problems such as occupying PCBA space and generating large heat, which leads to PCBA space size conflict design problems affecting the product module circuit.

[0003] However, these solutions are often costly and have limited reliability, making it difficult to meet the needs of certain applications. Therefore, there is an urgent need for an MPPT flyback auxiliary source high-low voltage input power supply activation switching power supply circuit with simple structure, low cost and high reliability to meet product needs. Summary of the invention

[0004] In order to solve the above problems, the present invention provides an MPPT flyback auxiliary source high and low voltage input power supply activation switching power supply circuit, which aims to solve the above problems. Through simple circuit design, automatic switching and isolation of high and low voltage input power supplies are realized to ensure stable operation of the equipment under various DC power supply conditions.

[0005] The present invention is implemented by the following technical scheme: an MPPT flyback auxiliary source high and low voltage input power supply activation switching power supply circuit, comprising: DC input terminal, used to receive MPPT DC power input; The primary auxiliary source input high and low voltage power supply activation switching power supply circuit has an input end connected to the DC input end, and an output end connected to the flyback basic topology primary absorption circuit, which is used to automatically activate the power supply within different input voltage ranges. The primary auxiliary source input high and low voltage power supply activation switching power supply circuit includes: The startup resistor is used for initial power supply and is connected in series between the DC input terminal and the source of Q1; A PMOS tube, whose source is connected to the DC input terminal, is current limited by a start-up resistor, and whose drain is connected to a primary absorption circuit of a flyback basic topology; Voltage stabilizing diodes ZD1 and ZD2 are used for voltage stabilization control, wherein ZD1 is connected between the gate of Q1 and the ground, and ZD2 is connected between the DC input terminal and the ground; An optocoupler, whose input end is connected to the secondary output circuit and whose output end is connected to the gate of Q1, is used to turn off Q1 and cut off the power supply of the primary startup resistor after the IC starts and stabilizes; The primary absorption circuit of the basic flyback topology has its input connected to the drain of the PMOS tube and its output connected to the main power voltage loop optocoupler control circuit, which is used to suppress the voltage spike during flyback conversion; The main power voltage loop optocoupler control circuit has an input end connected to the output end of the primary absorption circuit of the basic flyback topology, and an output end connected to the main power current loop detection control circuit and the IC_VCC winding working power supply circuit, for stabilizing the output voltage; The main power current loop detection control circuit has an input end connected to the output end of the main power voltage loop optocoupler control circuit, and an output end connected to the IC_VCC winding working power supply circuit and the secondary multi-channel output circuit, and is used to detect the output current and adjust the working state; IC_VCC winding working power supply circuit, whose input end is connected to the output end of the main power voltage loop optocoupler control circuit and the main power current loop detection control circuit, and whose output end is connected to IC, is used to provide a stable working power supply; The secondary multi-channel output circuit has its input end connected to the output end of the main power current loop detection control circuit, is used to provide multi-channel stable output voltage, and controls the power supply state of the PMOS tube through optical coupler feedback.

[0006] As a preferred technical solution, the DC input end is connected to an MPPT solar panel or a vehicle-mounted charging power supply to provide DC power supply, and an initial power supply is provided through current limiting resistors R1-R6.

[0007] As a preferred technical solution, the startup resistor is a 1206 chip resistor, one end of which is connected to the DC input terminal, and the other end is connected to the source of the PMOS tube.

[0008] As a preferred technical solution, the input end of the optical coupler is connected to the secondary multi-channel output circuit, the output end is connected to the gate of the PMOS tube, and the driving signal is stabilized by a voltage regulator diode to achieve automatic power supply switching.

[0009] As a preferred technical solution, automatic switching, isolation and stable power supply of high and low voltage input power supply are realized through R7, R8, C1, ZD1, OP1, Q1 and D2; When the input voltage is 12V-60V, R1-R6 provide stable power supply and the PMOS tube (Q1) is turned on; When the input voltage is 60V-150V, after the secondary multi-channel output circuit works, OP1 is turned on, Q1 is turned off, and R1-R6 is disconnected.

[0010] As a preferred technical solution, after the IC is activated and stabilized, the optical coupler receives a feedback signal from the secondary multi-channel output circuit, controls the Q1 PMOS tube to disconnect the power supply, and stops R1-R6 from continuously heating.

[0011] As a preferred technical solution, the flyback circuit topology includes: a transformer having a primary side connected to the drain of Q1 and a secondary side connected to a secondary multiple output circuit; Diode, for secondary rectification; Output capacitor, used to smooth the rectified output voltage.

[0012] As a preferred technical solution, the flyback basic topology primary absorption circuit absorbs high-frequency transient energy through an RCD clamping circuit to reduce the voltage stress of the primary winding of the transformer.

[0013] The beneficial effects of the present invention are as follows: the present invention provides an MPPT primary auxiliary source high and low voltage 12V-150V input power supply activation switching power supply circuit, and realizes automatic switching, isolation and stable power supply of the flyback auxiliary source working power supply through R7, R8, C1, ZD1, OP1, Q1, and D2. The circuit has the advantages of simple operation, low cost, and high reliability, and can realize high and low voltage 12V-150V input activation power supply, avoiding the problem of R1-R6 continuing to heat up and burn when activating power supply at 60V-150V while ensuring stable activation power supply at 12V-60V, and controlling the static loss problem of 60V-150V input power supply.

[0014] After the IC is activated and stabilized, the circuit of the present invention controls the Q1 PMOS tube to disconnect the power supply through the OP1 optical coupler, controls the continuous heating of the R1-R6 resistors, and reduces the input loss, so that R1-R6 can use ordinary SMD 1206 resistors, and does not need to use cement resistors or high-power plug-in resistors to deal with the heating problem of high-voltage input, saves material costs and device material space, and realizes automatic switching and isolation of high and low voltage input power supplies. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 It is a circuit schematic diagram of the present invention. DETAILED DESCRIPTION

[0017] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0018] Any feature disclosed in this specification (including any additional claims, abstract and drawings), unless otherwise stated, may be replaced by other equivalent or alternative features with similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0019] Figure 1 As shown, the present invention provides an MPPT flyback auxiliary source high and low voltage input power supply activation switching power supply circuit, which can automatically activate and switch power supply within a wide input voltage range of 12V-150V, improve the applicability and reliability of the power supply, and optimize the circuit structure, reduce power consumption and heating problems. Through a reasonably designed power supply switching circuit, this solution ensures stable startup of low voltage input (12V-60V) while avoiding continuous heating of the starting resistors R1-R6 under high voltage input (60V-150V), thereby reducing input loss and improving circuit reliability.

[0020] This circuit is suitable for MPPT solar charging systems, vehicle power systems, industrial DC power supply systems and other application scenarios to achieve efficient and stable DC power supply management.

[0021] In the specific implementation of the circuit, the circuit consists of the following main modules: DC input, primary auxiliary source input high and low voltage power supply activation switching power supply circuit, flyback basic topology primary absorption circuit, main power voltage loop optocoupler control circuit, main power current loop detection control circuit, IC_VCC winding working power supply circuit and secondary multi-channel output circuit. The modules work together to achieve automatic switching, isolation and stable power supply of high and low voltage input power supply, ensuring that the equipment can start normally and operate stably under different input voltage conditions.

[0022] During the operation of the system, the DC input terminal is used to receive the input voltage from the MPPT solar panel, car charger or other DC power supply equipment, and provide it to the entire circuit. In order to ensure that the system can adapt to a wide voltage input range, the input terminal of the primary auxiliary source input high and low voltage power supply activation switching power supply circuit is connected to the DC input terminal, and the output terminal is connected to the flyback basic topology primary absorption circuit. This circuit is mainly used to automatically activate the power supply in different input voltage ranges and ensure that the system maintains stable operation when the input voltage changes.

[0023] The primary auxiliary source input high and low voltage power supply activation switching power supply circuit is mainly composed of starting resistors R1-R6, PMOS tube Q1, voltage regulator diodes ZD1, ZD2, optocoupler OP1 and diode D2. The starting resistors R1-R6 are used to provide initial power supply and are connected in series between the DC input terminal and the source of Q1. At low voltage input (12V-60V), the resistor can stably provide initial startup power supply, allowing the system to start smoothly. However, at high voltage input (60V-150V), if you continue to rely on R1-R6 for power supply, the resistors will heat up or even be damaged due to excessive power consumption, so the optocoupler OP1 and Q1 need to be coordinated and controlled for automatic switching.

[0024] After the system starts normally, the secondary multi-channel output circuit provides a feedback signal to the optocoupler OP1, turning on the internal light-emitting diode of OP1, generating a low level at the output of the optocoupler, thereby reducing the gate voltage of Q1 to the cut-off state, and Q1 is turned off, cutting off the power supply path of the startup resistors R1-R6, effectively avoiding the problem of continuous heating of R1-R6 during high-voltage input, while reducing input power consumption, so that R1-R6 can use ordinary 1206 chip resistors instead of high-power cement resistors or plug-in resistors, thereby saving material costs and optimizing PCB space layout. In addition, the diode D2 is used to prevent reverse current when Q1 is turned off, protect the MOS tube, and improve the reliability of the circuit.

[0025] After Q1 is turned off, the input of the primary absorption circuit of the basic flyback topology is connected to the drain of Q1, and the output is connected to the main power voltage loop optocoupler control circuit. This circuit is mainly used to absorb high-frequency transient energy and suppress voltage spikes during flyback conversion to protect power components and ensure the stability of the power conversion process.

[0026] The input end of the main power voltage loop optocoupler control circuit is connected to the output end of the primary absorption circuit of the flyback basic topology, and the output end is connected to the main power current loop detection control circuit and the IC_VCC winding working power supply circuit. Its function is to stabilize the output voltage and adjust the input power supply state through optocoupler feedback to ensure that the system can maintain a constant output voltage under different load conditions.

[0027] The input end of the main power current loop detection control circuit is connected to the output end of the main power voltage loop optocoupler control circuit, and the output end is connected to the IC_VCC winding working power supply circuit and the secondary multi-channel output circuit. This module is used to detect the output current and dynamically adjust the working state of the system according to the load conditions to ensure the stability of the output voltage and current.

[0028] The input end of the IC_VCC winding working power supply circuit is connected to the output end of the main power voltage loop optocoupler control circuit and the main power current loop detection control circuit. Its function is to provide a stable working power supply for the IC to ensure the normal operation of the entire system. After the system is started, the circuit will provide a continuous and stable power supply for the IC, no longer relying on the startup resistors R1-R6, thereby further reducing power consumption and improving system reliability.

[0029] The input end of the secondary multi-channel output circuit is connected to the output end of the main power current loop detection control circuit, which is mainly used to provide multiple stable output voltages to the external load. In addition, the circuit provides a feedback signal through the optocoupler OP1 to control the power supply state of Q1, ensuring that the high and low voltage input power supply can be automatically switched and isolated. When the high voltage input is turned on, the optocoupler is turned off, and the power supply of R1-R6 is cut off to prevent overheating; when the low voltage input is turned on, the optocoupler is turned off, and Q1 is turned on, so that the startup resistors R1-R6 provide the initial power supply to achieve stable startup.

[0030] In the whole system, the flyback circuit topology also includes key components such as transformer T1, rectifier diodes D5, D6, output capacitors C5, C6, etc. The primary side of transformer T1 is connected to the drain of Q1, and the secondary side is connected to the secondary multi-way output circuit; When Q1 is turned on, the input power stores energy for the transformer, and then releases the energy to the secondary side during the flyback process, providing a stable DC output for the load. Rectifier diodes D5 and D6 are used to rectify the AC signal, and output capacitors C5 and C6 are used for filtering to make the output voltage more stable and ensure that the load can obtain a stable power supply.

[0031] In addition, the primary absorption circuit of the flyback basic topology absorbs high-frequency transient energy through the RCD clamp circuit, reduces the voltage stress of the primary winding of the transformer, improves the power conversion efficiency, and prevents high-frequency spike voltage from causing damage to power components. This design further improves the stability of the system, making it suitable for a wider range of application scenarios, including MPPT solar systems, vehicle charging systems, and other 12V-150V DC power supply equipment.

[0032] Through the above design, the present invention successfully solves the problems of high and low voltage input compatibility, heating of starting resistor, high voltage static loss, system power optimization, etc., and significantly improves the reliability and stability of power management. The circuit structure is simple and easy to implement, suitable for various application environments requiring efficient DC power supply, while reducing material costs and optimizing PCB space layout, achieving more efficient power management while ensuring safe operation of the system.

[0033] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that are not conceived through creative work should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope defined in the claims.

Claims

1. An MPPT flyback auxiliary source high and low voltage input power supply activation switching power supply circuit, characterized in that: include: DC input terminal, used to receive MPPT DC power input; The primary auxiliary source input high and low voltage power supply activation switching power supply circuit has an input end connected to the DC input end, and an output end connected to the flyback basic topology primary absorption circuit, which is used to automatically activate the power supply within different input voltage ranges. The primary auxiliary source input high and low voltage power supply activation switching power supply circuit includes: The startup resistor is used for initial power supply and is connected in series between the DC input terminal and the source of Q1; A PMOS tube, whose source is connected to the DC input terminal, is current limited by a start-up resistor, and whose drain is connected to a primary absorption circuit of a flyback basic topology; Voltage stabilizing diodes ZD1 and ZD2 are used for voltage stabilization control, wherein ZD1 is connected between the gate of Q1 and the ground, and ZD2 is connected between the DC input terminal and the ground; An optocoupler, whose input end is connected to the secondary output circuit and whose output end is connected to the gate of Q1, is used to turn off Q1 and cut off the power supply of the primary startup resistor after the IC starts and stabilizes; The primary absorption circuit of the basic flyback topology has its input connected to the drain of the PMOS tube and its output connected to the main power voltage loop optocoupler control circuit, which is used to suppress the voltage spike during flyback conversion; The main power voltage loop optocoupler control circuit has an input end connected to the output end of the primary absorption circuit of the flyback basic topology, and an output end connected to the main power current loop detection control circuit and the IC_VCC winding working power supply circuit, for stabilizing the output voltage; The main power current loop detection control circuit has an input end connected to the output end of the main power voltage loop optocoupler control circuit, and an output end connected to the IC_VCC winding working power supply circuit and the secondary multi-channel output circuit, and is used to detect the output current and adjust the working state; IC_VCC winding working power supply circuit, whose input end is connected to the output end of the main power voltage loop optocoupler control circuit and the main power current loop detection control circuit, and whose output end is connected to IC, is used to provide a stable working power supply; The secondary multi-channel output circuit has its input end connected to the output end of the main power current loop detection control circuit, is used to provide multi-channel stable output voltage, and controls the power supply state of the PMOS tube through optical coupler feedback.

2. The MPPT flyback auxiliary source high and low voltage input power supply activation switching power supply circuit according to claim 1 is characterized in that: The DC input end is connected to the MPPT solar panel or the vehicle-mounted charging power supply to provide DC power supply, and provides initial power supply through the current limiting resistors R1-R6.

3. The MPPT flyback auxiliary source high and low voltage input power supply activation switching power supply circuit according to claim 1 is characterized in that: The startup resistor is a 1206 chip resistor, one end of which is connected to the DC input terminal, and the other end is connected to the source of the PMOS tube.

4. The MPPT flyback auxiliary source high and low voltage input power supply activation switching power supply circuit according to claim 1 is characterized in that: The input end of the optical coupler is connected to the secondary multi-channel output circuit, the output end is connected to the gate of the PMOS tube, and the driving signal is stabilized by the voltage regulator diode to achieve automatic power supply switching.

5. The MPPT flyback auxiliary source high and low voltage input power supply activation switching power supply circuit according to claim 1, characterized in that: Automatic switching, isolation and stable power supply of high and low voltage input power supply are realized through R7, R8, C1, ZD1, OP1, Q1 and D2; When the input voltage is 12V-60V, R1-R6 provide stable power supply and the PMOS tube (Q1) is turned on; When the input voltage is 60V-150V, after the secondary multi-channel output circuit works, OP1 is turned on, Q1 is turned off, and R1-R6 is disconnected.

6. The MPPT flyback auxiliary source high and low voltage input power supply activation switching power supply circuit according to claim 1, characterized in that: After the IC is activated and stabilized, the optical coupler receives the feedback signal from the secondary multi-channel output circuit, controls the Q1 PMOS tube to disconnect the power supply, and stops R1-R6 from continuously heating.

7. The MPPT flyback auxiliary source high and low voltage input power supply activation switching power supply circuit according to claim 1, characterized in that: The flyback circuit topology includes: a transformer having a primary side connected to the drain of Q1 and a secondary side connected to a secondary multiple output circuit; Diode, for secondary rectification; Output capacitor, used to smooth the rectified output voltage.

8. The MPPT flyback auxiliary source high and low voltage input power supply activation switching power supply circuit according to claim 1, characterized in that: The flyback basic topology primary absorption circuit absorbs high-frequency transient energy through an RCD clamping circuit, thereby reducing the voltage stress of the primary winding of the transformer.

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