Switching power supply protection circuit and power supply system

Abstract

The switching power supply protection circuit and power supply system proposed in this application include: a control module; a charging circuit, the input terminal of which is connected to the switching power supply, the output terminal of which is connected to a capacitor, and the charging circuit is communicatively connected to the control module; and a parallel switch, the first terminal of which is connected to the output terminal of the charging circuit, the second terminal of which is connected to both the output terminal of the charging circuit and the load output terminal, the switching power supply being connected to the load output terminal, and the parallel switch being communicatively connected to the control module. When the switching power supply is powered on, the control module controls the parallel switch to be in the open state and starts the charging circuit to charge the capacitor. When the voltage of the capacitor is detected to reach a preset voltage threshold, the control module also controls the parallel switch to be closed, so that the switching power supply and the supercapacitor supply power to the load output terminal in parallel, significantly improving the safety, reliability, and stability of the entire power supply system.

Description

Technical Field

[0001] This application relates to the field of circuit technology, and in particular to switching power supply protection circuits and power supply systems. Background Technology

[0002] In technical fields such as magnetic drive conveyor systems, which have high peak power requirements, a power supply scheme using a parallel connection of a switching power supply and a supercapacitor is commonly employed. This allows the switching power supply to provide a stable base power, while the supercapacitor meets the instantaneous high power demands during load startup or dynamic changes. However, in this parallel power supply scheme, when the system is initially powered on, the fully discharged supercapacitor acts as a near-short-circuit load for the switching power supply. This causes the switching power supply to output a surge current far exceeding its rated value during charging, immediately triggering its built-in overcurrent protection function and stopping operation, preventing the entire system from starting normally. Especially in applications with multiple devices connected in parallel on a large scale, the enormous instantaneous total impact power can severely impact the factory's overall power supply network, posing a risk of tripping the main switch. This results in a relatively low safety profile for power supply circuits that commonly use a parallel connection of a switching power supply and a supercapacitor. Utility Model Content

[0003] This utility model provides a switching power supply protection circuit and power supply system, which can improve the safety of power supply circuits that use a switching power supply and a supercapacitor in parallel.

[0004] To achieve the above objectives, a first aspect of this application provides a switching power supply protection circuit, comprising: Control module; A charging circuit, wherein the input terminal of the charging circuit is connected to a switching power supply, the output terminal of the charging circuit is connected to a capacitor, and the charging circuit is communicatively connected to the control module; A parallel switch is provided, wherein the first end of the parallel switch is connected to the output terminal of the charging circuit, the second end of the parallel switch is connected to both the output terminal of the charging circuit and the load output terminal, the switching power supply is connected to the load output terminal, and the parallel switch is communicatively connected to the control module. When the switching power supply is powered on, the control module is used to control the parallel switch to be in the open state and start the charging circuit to charge the capacitor; When the voltage of the capacitor is detected to reach a preset voltage threshold, the control module is also used to control the parallel switch to close, so that the switching power supply and the capacitor supply power to the load output terminal in parallel.

[0005] In some embodiments, the charging circuit is a power conversion circuit including at least one power switching element, and the control module adjusts the output current of the charging circuit by adjusting the operating state of the power switching element.

[0006] In some embodiments, the charging circuit includes a first high-side MOSFET, a second high-side MOSFET, a first low-side MOSFET, a second low-side MOSFET, and an inductor; Wherein, the drain of the first high-side MOSFET is connected to the switching power supply, the source of the first high-side MOSFET is connected to the drain of the first low-side MOSFET and the first end of the inductor, and the source of the first low-side MOSFET is grounded. The second end of each inductor is connected to the source of the second high-side MOSFET and the drain of the second low-side MOSFET. The drain of the second high-side MOSFET is connected to the input terminal of the capacitor, and the source of the second low-side MOSFET is grounded.

[0007] In some embodiments, it also includes: A first current sampling unit is disposed at the output terminal of the switching power supply; The second current sampling unit is located at the output terminal of the charging circuit.

[0008] In some embodiments, the parallel switch is a magnetic latching relay.

[0009] In some embodiments, it also includes: A temperature sensor is disposed on one side of the capacitor to detect the capacitor temperature in real time, and the temperature sensor is communicatively connected to the control module.

[0010] In some embodiments, it also includes: A voltage sampling unit is disposed on one side of the capacitor and is used to detect the capacitor voltage in real time. The voltage sampling unit is communicatively connected to the control module.

[0011] In some embodiments, it also includes: A filter capacitor, the positive terminal of which is connected to the output terminal of the switching power supply, and the negative terminal of which is grounded.

[0012] In some embodiments, a communication interface is connected to the control module; The control module is also used to send at least one of the following information to the host computer via the communication interface: the voltage of the capacitor, the charging current, or the circuit operating status.

[0013] A second aspect of this application provides a power supply system, comprising: Switching power supply; Capacitors; and As described in the first aspect, the input terminal of the switching power supply protection circuit is connected to the output terminal of the switching power supply, and the output terminal of the protection circuit is connected to the capacitor.

[0014] The embodiments of this utility model include at least the following beneficial effects: The switching power supply protection circuit and power supply system proposed in this application embodiment include: a control module; a charging circuit, the input terminal of which is connected to the switching power supply, the output terminal of which is connected to a capacitor, and the charging circuit is communicatively connected to the control module; and a parallel switch, the first terminal of which is connected to the output terminal of the charging circuit, the second terminal of which is connected to both the output terminal of the charging circuit and the load output terminal, the switching power supply being connected to the load output terminal, and the parallel switch being communicatively connected to the control module. When the switching power supply is powered on, the control module controls the parallel switch to be in the open state and starts the charging circuit to charge the capacitor. When the voltage of the capacitor is detected to reach a preset voltage threshold, the control module also controls the parallel switch to be closed, so that the switching power supply and the supercapacitor supply power to the load output terminal in parallel. Based on this, in this application embodiment, by setting the control module, the charging circuit, and the parallel switch, the "charging process" in the initial stage of power-on and the "parallel power supply process" in the normal operation stage are effectively separated. Upon power-up, the control module first keeps the parallel switch open and starts a dedicated charging circuit to charge the supercapacitor in a controlled manner. This actively limits the charging current to a safe and controllable range, thereby completely avoiding the huge surge current generated by the switching power supply directly facing the supercapacitor which is equivalent to a short circuit. This ensures that the switching power supply itself will not trigger overcurrent protection and guarantees that a single power supply unit can reliably complete the startup. Furthermore, in large systems with multiple devices connected in parallel, since the startup current of each unit is effectively suppressed, the total impact power at the moment of power-up is greatly reduced, thereby eliminating the risk of tripping the factory's main switch and significantly improving the safety, reliability, and stability of the entire power supply system.

[0015] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of this invention may be realized and obtained by means of the structures particularly pointed out in the description, claims, and drawings. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the switching power supply protection circuit provided in the embodiment of this application.

[0017] Figure 2 This is a circuit diagram of a switching power supply protection circuit provided in another embodiment of this application.

[0018] Figure 3 This is a schematic diagram of the power supply system provided in another embodiment of this application. Detailed Implementation

[0019] In the description of this utility model, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this utility model.

[0020] It should be understood that in the description of the embodiments of this utility model, "a few" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If "first," "second," etc., are used in the description, they are only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the sequential relationship of the indicated technical features.

[0021] In the description of the embodiments of this utility model, unless otherwise explicitly limited, terms such as setting, installation, and electrical connection should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in the embodiments of this utility model in conjunction with the specific content of the technical solution.

[0022] In the description of this utility model, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0023] In technical fields such as magnetic drive conveyor systems, which have high peak power requirements, a power supply scheme using a parallel connection of a switching power supply and a supercapacitor is commonly employed. This allows the switching power supply to provide a stable base power, while the supercapacitor meets the instantaneous high power demands during load startup or dynamic changes. However, in this parallel power supply scheme, when the system is initially powered on, the fully discharged supercapacitor acts as a near-short-circuit load for the switching power supply. This causes the switching power supply to output a surge current far exceeding its rated value during charging, immediately triggering its built-in overcurrent protection function and stopping operation, preventing the entire system from starting normally. Especially in applications with multiple devices connected in parallel on a large scale, the enormous instantaneous total impact power can severely impact the factory's overall power supply network, posing a risk of tripping the main switch. This results in a relatively low safety profile for power supply circuits that commonly use a parallel connection of a switching power supply and a supercapacitor.

[0024] To improve the safety of power supply circuits using a switching power supply and a supercapacitor in parallel, this embodiment effectively separates the "charging process" during the initial power-on phase from the "parallel power supply process" during normal operation by setting up a control module, a charging circuit, and a parallel switch. Upon power-on, the control module first keeps the parallel switch open and activates a dedicated charging circuit to charge the supercapacitor in a controlled manner. This actively limits the charging current to a safe and controllable range, thereby completely avoiding the huge surge current generated by the switching power supply directly facing the supercapacitor, which is equivalent to a short circuit. This ensures that the switching power supply itself will not trigger overcurrent protection, guaranteeing that a single power supply unit can reliably complete the startup. Furthermore, in large systems with multiple devices connected in parallel, because the startup current of each unit is effectively suppressed, the total impact power at the moment of power-on is significantly reduced, thus eliminating the risk of tripping the factory's main switch and significantly improving the safety, reliability, and stability of the entire power supply system.

[0025] This application provides a switching power supply protection circuit and power supply system, which are specifically described through the following embodiments.

[0026] To better describe the switching power supply protection circuit and power supply system provided in the embodiments of this application, in this embodiment, reference is made to... Figure 1 The diagram shown is a structural schematic of the switching power supply protection circuit provided in an embodiment of this application. Figure 1The diagram illustrates a functional block diagram of a switching power supply protection circuit. By introducing an intelligently controlled intermediate link between the power module and the capacitor, the system startup process is divided into two independent stages: "controlled pre-charging" and "parallel power supply." Specifically, the power module's output is directly connected to the load output on one hand, and on the other hand, it is connected to the capacitor through a charging circuit managed by the control module. In the initial power-on stage, the control module keeps the parallel switch open and starts the charging circuit to pre-charge the capacitor with the power module's energy in a controlled manner. Once the capacitor voltage reaches a preset value, the control module closes the parallel switch, connecting the capacitor and the power module in parallel to jointly supply power to the load output. This phased design cleverly utilizes the charging circuit to isolate the direct impact of the capacitor on the power module at the moment of power-on, thus achieving a smooth and safe system startup.

[0027] based on Figure 1 The schematic diagram of the switching power supply protection circuit shown is illustrated below. The switching power supply protection circuit provided in the embodiments of this application will be further described below.

[0028] Reference Figure 2 This is a circuit diagram of the switching power supply protection circuit provided in an embodiment of this application. Figure 2 As shown, the switching power supply protection circuit includes a control module that serves as the core control unit. This control module, typically implemented by a microcontroller (MCU), digital signal processor (DSP), or other programmable logic devices, primarily functions to precisely coordinate and manage the circuit's operating timing and key components based on preset program logic and real-time status information collected from various parts of the circuit. It is the decision-making center for realizing the circuit's protection function and intelligent operation strategy.

[0029] like Figure 2 As shown, the switching power supply serves as the energy input stage of the circuit. Its input terminals are used to connect to an external AC power source (e.g., the live wire L, neutral wire N, and ground wire PE of the mains). Its function is to convert the unstable external AC power into a stable DC power supply voltage, which becomes the output voltage of the subsequent load of the circuit (e.g., ...). Figure 2 The “OUT” terminal shown provides basic operating power. This load output is used to provide power to external load devices.

[0030] like Figure 2As shown, the switching power supply protection circuit also includes a charging circuit, which serves as a controlled energy conversion channel. Its input is connected to the DC output of the switching power supply to acquire electrical energy, and its output is connected to the capacitor to be charged to supply energy to the capacitor. This charging circuit establishes a communication connection with the control module, enabling the control module to dynamically adjust the operating state of the charging circuit according to a preset algorithm (e.g., a constant current or constant voltage charging strategy), such as by adjusting the internal power switching devices (e.g.,...). Figure 2 The switching frequency or duty cycle of the MOSFETs Q4, Q5, Q6, and Q7 shown in the figure can be precisely controlled to control the amount of charging current flowing to the capacitor, thereby achieving "soft-start" charging of the capacitor.

[0031] The charging circuit is an active and controllable power conversion circuit, which contains at least one power switching element (such as a MOSFET or IGBT). The control module actively adjusts the operating state of these power switching elements (such as the switching frequency and duty cycle) to precisely control the output current of the charging circuit, thereby achieving safe and controllable pre-charging of the capacitor.

[0032] It is understood that the purpose of the charging circuit in this application is to achieve safe and controllable pre-charging of the capacitor, rather than being limited to a specific implementation method. Specifically, this charging circuit is fundamentally different from the scheme of directly connecting the power supply and the capacitor during system power-on, resulting in "full-power direct charging," and aims to actively avoid the generation of inrush current. At the same time, this circuit does not use the traditional passive energy dissipation method of series current limiting with high-power aluminum-cased resistors, but rather improves charging efficiency and controllability through active power conversion. Therefore, the power switching element that implements its function is not limited to MOSFETs; any other high-power device capable of achieving controlled switching functions, such as bipolar junction transistors (BJTs) and insulated-gate bipolar transistors (IGBTs), can be used.

[0033] To achieve efficient and precise control of the charging process, the charging circuit is specifically a synchronous buck chopper circuit including at least one MOSFET. This synchronous buck chopper circuit is a high-efficiency DC-DC converter that utilizes a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) as a high-speed electronic switch. Compared to traditional buck circuits that use diodes for freewheeling, the synchronous chopper circuit uses another MOSFET instead of a diode, significantly reducing conduction losses and thus improving energy conversion efficiency. In this circuit, the control module generates a pulse width modulation (PWM) signal to adjust the switching frequency or duty cycle of the MOSFET. The duty cycle refers to the ratio of the MOSFET's on-time to the total cycle within one switching cycle. By changing this ratio, the control module can precisely adjust the equivalent output voltage of the chopper circuit, thereby achieving closed-loop control of the charging current from the switching power supply input to the charging circuit, ensuring that the charging process always operates within the preset safety parameter range.

[0034] In some embodiments, to achieve more flexible and powerful current control capabilities, such as Figure 2 As shown, the synchronous buck chopper circuit further employs a specific topology comprising a first high-side MOSFET Q4, a second high-side MOSFET Q5, a first low-side MOSFET Q6, a second low-side MOSFET Q7, and an inductor. This structure is similar to a full-bridge circuit, where the four MOSFETs form two half-bridge arms, and the inductor serves as the core energy storage and current smoothing element. The specific circuit connection is as follows: the first high-side MOSFET (i.e., Figure 2 The drain of Q4 in the circuit serves as the input terminal, connected to the positive terminal of the switching power supply; its source is connected to the first low-side MOSFET (i.e., Figure 2 The drain of the first low-side MOSFET (Q6) and the first terminal of the inductor are connected together to form the first switching node, while the source of the first low-side MOSFET is connected to the circuit ground. Correspondingly, the second terminal of the inductor is connected to the second high-side MOSFET (Q6). Figure 2 The source of Q5 and the second low-side MOS transistor (i.e., Q5) Figure 2 The drains of the second high-side MOSFET (Q7) are connected together to form the second switching node; the drain of the second high-side MOSFET serves as the output terminal of the circuit and is connected to the positive terminal of the capacitor, while the source of the second low-side MOSFET is also connected to the circuit ground. This full-bridge structure provides the control module with a variety of switching combination strategies, enabling it to establish the required voltage across the inductor very precisely, thereby driving and controlling the charging current flowing to the capacitor, and adapting to a wider voltage and current regulation range.

[0035] In the embodiments of this application, such as Figure 2As shown, the control module uses the control interface H1 of the first high-side MOSFET Q4, the control interface H2 of the second high-side MOSFET Q5, the control interface L1 of the first low-side MOSFET Q6, and the control interface L1 of the second low-side MOSFET Q7 to adjust the switching frequency or duty cycle of the MOSFETs by generating pulse width modulation (PWM) signals.

[0036] This embodiment of the application specifies the charging circuit as a synchronous buck chopper circuit and adopts a specific four-MOSFET full-bridge topology. Utilizing the high efficiency of the synchronous buck scheme, energy loss during charging is significantly reduced, improving the overall energy efficiency of the system. Secondly, the control module precisely controls the current by adjusting the duty cycle of the MOSFETs, enabling the system to implement complex charging strategies such as constant current and constant voltage. This not only protects the switching power supply but also optimizes capacitor charging management, extending its lifespan. Finally, the robust, flexible, and powerful full-bridge topology provides a reliable hardware foundation for achieving high-current, high-precision charging control, ensuring that the entire protection circuit can still efficiently and stably perform its core protection functions even in demanding high-power application scenarios.

[0037] like Figure 2 As shown, the circuit includes a parallel switch. The first end of the parallel switch is connected to the node between the output of the charging circuit and the input of the capacitor, while the second end is connected to the load output of the system. Simultaneously, a path is directly led from the output of the switching power supply to this load output. This parallel switch also establishes a communication connection with and is controlled by the control module. This connection method allows the parallel switch to determine whether the capacitor is charged solely through the charging circuit or connected in parallel with the switching power supply to jointly power the load.

[0038] In some embodiments, to improve system energy efficiency and long-term operational reliability, magnetic latching relays are preferably used as parallel switches. It is understood that a magnetic latching relay is a bistable switching device that uses the magnetic force of an internal permanent magnet to maintain the closed or open state of its contacts, requiring only a pulse current to drive its coil during the state transition. Once the state transition is complete, the coil does not need to be continuously energized, and its power consumption is almost zero. Compared to ordinary relays that require continuous energization to maintain the engaged state, this significantly reduces the static power consumption and heat generation of the circuit under normal parallel power supply mode.

[0039] To achieve comprehensive monitoring of the circuit's operating status, this switching power supply protection circuit also includes a first current sampling unit (such as...). Figure 2(The "sampling resistor" shown on the left). This first current sampling unit, typically composed of a precision sampling resistor or a Hall effect sensor, is connected in series in the main circuit of the switching power supply's output. Its function is to monitor the total current flowing from the switching power supply in real time. This current value includes not only the charging current of the capacitors but also the current that may be directly supplied to the load. This unit feeds back the monitored total current information to the control module, providing the system with a top-level overcurrent protection basis to prevent excessive current surges to the switching power supply itself or the external power grid under any operating conditions.

[0040] In some embodiments, to achieve precise closed-loop control of the charging process, the circuit further includes a second current sampling unit (such as...). Figure 2 (The "sampling resistor" is shown on the right). This second current sampling unit is located at the output of the charging circuit, specifically on the path between the charging circuit and the capacitor. Its function is to specifically and accurately measure the actual charging current flowing to the capacitor. The control module compares the real-time current value fed back by this unit with the internally set target charging current value, and dynamically adjusts the operating parameters of the charging circuit (such as the PWM duty cycle) based on the difference, thereby forming a closed-loop feedback control system to ensure that the charging process of the capacitor (e.g., constant current charging) can be executed accurately and stably.

[0041] This application embodiment constructs a dual current monitoring system by setting up a first current sampling unit and a second current sampling unit: the second current sampling unit ensures precise internal control of the capacitor charging process, while the first current sampling unit provides global safety monitoring of the total system input current. The two work together to make the protection strategy more comprehensive and robust. Simultaneously, using a magnetic latching relay as a parallel switch, with its zero-power latching characteristic, significantly reduces the operating energy consumption of the protection circuit itself, improving the energy efficiency and long-term operational stability of the entire power supply system, making it particularly suitable for applications requiring continuous operation for extended periods.

[0042] To further enhance circuit safety, such as Figure 2 As shown, the switching power supply protection circuit also includes a temperature sensor. This temperature sensor, such as a thermistor or an integrated temperature sensing chip, is positioned close to one side of the capacitor to detect its temperature in real time. The temperature sensor is communicatively connected to the control module, continuously sending the collected temperature data to it. This allows the control module to monitor the thermal state of the capacitor during charging or high-current discharging. If the temperature exceeds a preset safety threshold, protective measures such as derating, suspending operation, or issuing an alarm can be taken, effectively preventing damage to the capacitor due to overheating or causing safety accidents.

[0043] In some embodiments, to provide the control module with crucial information for executing its core logic, the circuit also includes a voltage sampling unit. This voltage sampling unit, typically composed of a precision voltage divider resistor network and a signal conditioning circuit, is also positioned on one side of the capacitor (i.e., connected in parallel across the capacitor) to detect the capacitor voltage in real time. This voltage sampling unit is also communicatively connected to the control module. Based on the real-time voltage value fed back by this unit, the control module accurately determines whether the capacitor has charged to a preset voltage threshold, thereby deciding when to end the pre-charging phase and close the parallel switch, ensuring the accuracy and timeliness of state switching.

[0044] In some embodiments, to improve the power supply quality of the entire circuit, such as Figure 2 As shown, the circuit also includes a filter capacitor. The positive terminal of this filter capacitor is connected to the output of the switching power supply, while its negative terminal is grounded. The main function of this capacitor is to smooth the DC voltage output by the switching power supply, filtering out ripple and high-frequency noise. By providing a more stable and cleaner DC power supply, this filter capacitor not only ensures the reliable operation of sensitive electronic components such as the control module and charging circuit, but also provides higher-quality power to the downstream loads, contributing to improved system stability and performance.

[0045] In some embodiments, to achieve remote monitoring and intelligent management of this protection circuit, the circuit further includes a communication interface connected to the control module. This communication interface can be an industrial fieldbus interface such as CAN, RS485, or Ethernet. The control module is also used to send at least one of the following information—capacitor voltage, charging current, or circuit operating status—to a host computer (e.g., a personal computer PC, a programmable logic controller (PLC), or a central monitoring system) via the communication interface. This function enables the switching power supply protection circuit provided in this application to no longer be an isolated information system, but rather to be integrated into the entire automation system network, facilitating remote status monitoring, data recording, and fault diagnosis by operators.

[0046] This application expands the function of the switching power supply protection circuit from a simple startup protection to a comprehensive and intelligent system-level management unit. The temperature sensor and voltage sampling unit provide the control module with accurate and real-time status awareness, forming the foundation for refined safety control; the filter capacitor ensures stable circuit operation from the source of power quality; and the communication interface enables information exchange between the device and the host system, greatly improving the maintainability, manageability, and intelligence of the entire power supply system, enabling it to better adapt to the needs of modern, networked industrial applications.

[0047] In some embodiments, when the external power supply is turned on and the switching power supply starts working, the control module immediately executes a preset startup procedure. In the initial stage of this procedure, the control module first ensures that the parallel switch is in the open state, thereby electrically isolating the capacitor from the main output path of the switching power supply. Next, the control module activates the charging circuit, utilizing its current-limiting function to obtain energy from the switching power supply and charge the capacitor with a stable, controlled current. This operation effectively avoids the huge current surge to the switching power supply caused by a fully discharged capacitor at the moment of power-on.

[0048] In some embodiments, as the charging process proceeds, when the voltage sampling unit in the circuit detects that the voltage across the capacitor has risen and reached a preset voltage threshold (this threshold is typically set to be close to or slightly lower than the stable output voltage of the switching power supply), the control module determines that the pre-charging phase is complete. At this time, the control module issues a command to drive the parallel switch from the open state to the closed state. Once the parallel switch is closed, the output terminal of the capacitor is directly connected to the output terminal of the switching power supply, forming a parallel structure to jointly supply power to the load output terminal, thus seamlessly transitioning the system to the normal high-performance power supply operating mode.

[0049] In summary, the switching power supply protection circuit provided in this application coordinates the timing of the charging circuit and parallel switch through a control module, cleverly decomposing the system power-on process into two stages: "isolation pre-charging" and "closing parallel connection." The switching power supply protection circuit provided in this application uses a dedicated charging circuit to perform controllable current-limited charging of the capacitor, fundamentally solving the technical problem of triggering overcurrent protection or even causing grid tripping due to huge surge currents when the switching power supply directly charges large-capacity capacitors. After the capacitor voltage and power supply voltage are basically matched, the parallel connection is achieved by closing the parallel switch, avoiding secondary impacts at the moment of switching, thereby significantly improving the startup reliability, operational stability, and safety of the entire power supply system.

[0050] In addition, this application also provides a complete power supply system designed to provide stable and reliable power to loads with high peak power requirements, such as magnetic drive conveyor equipment.

[0051] Reference Figure 3 This is a schematic diagram of the power supply system provided in an embodiment of this application. Figure 3 As shown, the power supply system comprises three core components in its overall architecture: a switching power supply that serves as the basic energy source (…). Figure 3 The "power module" shown includes a capacitor as an energy storage unit and a switching power supply protection circuit as described above.

[0052] In some embodiments, the switching power supply in this power supply system is the primary energy source for the entire system. Its function is to convert external AC or unstable DC power into stable DC power required by the load devices. It provides continuous and stable base power to the system and is the cornerstone for ensuring long-term system operation. The capacitors in this power supply system, typically supercapacitors with extremely high capacitance and power density in such applications, primarily function as energy buffer units. They smoothly obtain and store energy from the switching power supply and can release large currents very quickly when the load requires instantaneous high power (e.g., device startup or acceleration) to compensate for the insufficient peak output capability of the switching power supply. The switching power supply protection circuit plays a crucial role as an intelligent interface and protection core in the system. Based on its connection relationship, the input of the switching power supply protection circuit is connected to the output of the switching power supply for obtaining electrical energy and monitoring the power status; the output of the protection circuit is connected to the capacitor for controlled charging management of the capacitor. This layout precisely places the protection circuit between the power supply and the energy storage unit, enabling it to effectively manage the energy flow between the two, especially in the initial stage of system power-on.

[0053] Once the capacitor is fully charged, the parallel switch closes, and the power module and the capacitor together provide a continuous and stable power supply to the load output terminal, so as to provide power to the load device through the load output terminal.

[0054] By organically combining the switching power supply, capacitor, and the switching power supply protection circuit proposed in this application into a complete power supply system, the technical problem of excessive startup inrush current, which prevents the system from starting normally, is fundamentally solved in the prior art when the two are directly connected in parallel. This power supply system utilizes the switching power supply protection circuit to achieve safe pre-charging of the capacitor, ensuring that the entire system can start smoothly and reliably. On this basis, it fully leverages the synergistic advantages of the switching power supply providing continuous power and the capacitor providing peak power, thus providing an ideal power supply solution for high-performance load equipment that is both safe and stable and has high dynamic response capability.

[0055] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0056] It should also be understood that the various implementation methods provided in this utility model embodiment can be combined arbitrarily to achieve different technical effects.

[0057] The above is a detailed description of the preferred embodiments of the present utility model. However, the present utility model is not limited to the above embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present utility model. All such equivalent modifications or substitutions are included within the scope defined by the claims of the present utility model.

Claims

1. A switching power supply protection circuit, characterized by comprising: include: Control module; A charging circuit, wherein the input terminal of the charging circuit is connected to a switching power supply, the output terminal of the charging circuit is connected to a capacitor, and the charging circuit is communicatively connected to the control module; A parallel switch is provided, wherein the first end of the parallel switch is connected to the output terminal of the charging circuit, the second end of the parallel switch is connected to both the output terminal of the charging circuit and the load output terminal, the switching power supply is connected to the load output terminal, and the parallel switch is communicatively connected to the control module. When the switching power supply is powered on, the control module is used to control the parallel switch to be in the open state and start the charging circuit to charge the capacitor; When the voltage of the capacitor is detected to reach a preset voltage threshold, the control module is also used to control the parallel switch to close, so that the switching power supply and the capacitor supply power to the load output terminal in parallel.

2. The switching power supply protection circuit according to claim 1, wherein The charging circuit is a power conversion circuit including at least one power switching element. The control module adjusts the output current of the charging circuit by adjusting the operating state of the power switching element.

3. The switching power supply protection circuit according to claim 2, wherein The power conversion circuit includes a first high-side MOSFET, a second high-side MOSFET, a first low-side MOSFET, a second low-side MOSFET, and an inductor; Wherein, the drain of the first high-side MOSFET is connected to the switching power supply, the source of the first high-side MOSFET is connected to the drain of the first low-side MOSFET and the first end of the inductor, and the source of the first low-side MOSFET is grounded. The second terminal of each inductor is connected to the source of the second high-side MOSFET and the drain of the second low-side MOSFET. The drain of the second high-side MOSFET is connected to the input terminal of the capacitor, and the source of the second low-side MOSFET is grounded.

4. The switching power supply protection circuit of claim 1, wherein Also includes: A first current sampling unit is disposed at the output terminal of the switching power supply; The second current sampling unit is located at the output terminal of the charging circuit.

5. The switching power supply protection circuit of claim 1, wherein The parallel switch is a magnetic latching relay.

6. The switching power supply protection circuit of claim 1, wherein Also includes: A temperature sensor is disposed on one side of the capacitor to detect the capacitor temperature in real time, and the temperature sensor is communicatively connected to the control module.

7. The switching power supply protection circuit according to claim 1, characterized in that, Also includes: A voltage sampling unit is disposed on one side of the capacitor and is used to detect the capacitor voltage in real time. The voltage sampling unit is communicatively connected to the control module.

8. The switching power supply protection circuit according to claim 1, characterized in that, Also includes: A filter capacitor, the positive terminal of which is connected to the output terminal of the switching power supply, and the negative terminal of which is grounded.

9. The switching power supply protection circuit according to claim 1, characterized in that, Also includes: A communication interface, connected to the control module; The control module is also used to send at least one of the following information to the host computer via the communication interface: the voltage of the capacitor, the charging current, or the circuit operating status.

10. A power supply system, characterized in that, include: Switching power supply; capacitance; as well as The switching power supply protection circuit according to any one of claims 1 to 9, wherein the input terminal of the switching power supply protection circuit is connected to the output terminal of the switching power supply, and the output terminal of the protection circuit is connected to the capacitor.

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