Multifunctional low-power-consumption power distribution terminal power supply system

Abstract

The invention provides a multifunctional low-power-consumption power distribution terminal power supply system which comprises a filtering and rectifying unit. The charging and discharging management unit is integrated with an intelligent charging and discharging control algorithm, performs charging and discharging management on the charging process of the capacitor and the battery, and switches to a battery discharging mode to provide a starting power supply when the voltage of the capacitor is insufficient; wherein the intelligent charging and discharging control algorithm is an algorithm based on the combination of a fuzzy logic control algorithm and a dynamic threshold adjustment strategy; the PWM control unit is used for outputting voltage by adopting a pulse width modulation technology and automatically reducing the power to the lowest level in a non-working state; and the CPU control unit is used for controlling the normal operation of the charging and discharging management unit and the PWM control unit, and monitoring the working states of the three-stage rectification topological structure, the grading protection circuit and the high-precision acquisition circuit in real time through a built-in intelligent monitoring algorithm. Stable, reliable, efficient and low-power-consumption power supply support can be provided for the power distribution terminal, and further development of an intelligent power grid is promoted.

Description

Technical Field

[0001] The present invention relates to the technical field of power distribution automation, and in particular to a multifunctional low-power distribution terminal power supply system. Background Art

[0002] As smart grid construction continues to advance, distribution terminals, as a crucial component of smart grids, are expanding in number and distribution. These terminals play a key role in monitoring, controlling, and protecting the power system, and a stable and reliable power supply system is essential for ensuring their normal operation.

[0003] Traditional power distribution terminal power systems are generally characterized by limited functionality and high power consumption. Since distribution terminals are often deployed outdoors, in remote areas, and in complex environments with limited energy supply, the high power consumption of traditional power systems not only accelerates the wear of energy storage components such as batteries, shortening equipment lifespan and increasing maintenance costs, but can also lead to an inability to continuously power distribution terminals when energy supply is insufficient, impacting the stable operation of the power system.

[0004] In existing distribution terminal power systems, the control algorithms used by the charge and discharge management units are often relatively simple, making it difficult to achieve precise control over the charging and discharging processes of capacitors and batteries. For example, some systems only use fixed charging current and voltage parameters for charging, failing to dynamically adjust based on the real-time status of the capacitors and batteries (such as voltage, charge level, and temperature). This can easily lead to slow and inefficient capacitor charging, or battery overcharge and over-discharge, seriously affecting the service life of the capacitors and batteries and reducing the reliability of the entire power system. For example, the traditional constant current-constant voltage charging method uses a fixed current at the beginning of charging, switching to constant voltage charging when the battery voltage reaches a certain value. However, this charging method does not fully account for individual battery differences (such as internal resistance and capacity differences between battery batches) and the performance variations of batteries in different operating environments (such as the impact of temperature on battery charge and discharge performance). In low-temperature environments, the internal resistance of batteries increases. If charging is still performed with a fixed current, uneven heating of the batteries can occur, even damaging the batteries. In high-temperature environments, excessively high charging currents can accelerate battery aging and shorten battery life.

[0005] Existing power systems lack flexibility in switching between charge and discharge modes when faced with emergencies such as insufficient capacitor voltage. Some systems fail to detect capacitor voltage changes promptly, or the switch to battery discharge mode takes a long time to respond. This can lead to brief power outages during the startup phase of the distribution terminal, impacting normal startup and operation. Furthermore, when battery power is low, some systems lack a sound power allocation strategy, failing to prioritize power supply to critical equipment, further reducing the operational stability of the distribution terminal under complex operating conditions.

[0006] Furthermore, existing hierarchical protection circuits have several flaws in their protection mechanisms. For example, overcurrent protection modules typically utilize a single-loop monitoring structure. If the monitoring circuit fails, overcurrent conditions cannot be detected promptly, potentially causing damage to the equipment. Furthermore, protection thresholds are often fixed and cannot be dynamically adjusted based on the system's actual operating conditions. This can lead to misoperation or failure to operate under conditions of large load fluctuations or harsh operating environments. In acquisition circuits, the accuracy and range of voltage acquisition often fail to meet practical requirements. This is particularly true when acquiring small voltage signals, where errors can be significant, hindering accurate assessment of the power system's status. Furthermore, the voltage acquisition range is limited, failing to cover the full range of low to high voltage measurements. When the input voltage exceeds the range, data can be distorted or even damage the acquisition circuit. Existing current acquisition circuits can suffer from noise interference and signal attenuation during signal conversion and processing, preventing them from accurately reflecting the actual current value, which in turn affects the power system's precise control of the charging and discharging processes. Summary of the Invention

[0007] In response to the above-mentioned problems existing in the existing distribution terminal power supply system, the present invention provides a multifunctional low-power distribution terminal power supply system, which, through the collaboration of architecture optimization and intelligent algorithms, can provide stable, reliable, efficient, and low-power power supply support for the distribution terminal, thereby improving the performance and reliability of the distribution terminal and promoting the further development of the smart grid.

[0008] The present invention achieves the above-mentioned purpose through the following technical solutions: A multifunctional low-power distribution terminal power supply system, comprising: The filter and rectifier unit is used to filter and rectify the input voltage and output DC voltage to ensure that the entire power module operates stably with low power consumption; The charge and discharge management unit integrates an intelligent charge and discharge control algorithm to manage the charging process of the capacitor and the battery. When the capacitor voltage is insufficient, it switches to battery discharge mode to provide starting power. The intelligent charge and discharge control algorithm is based on a combination of fuzzy logic control algorithm and dynamic threshold adjustment strategy. The PWM control unit uses pulse width modulation technology to output 380V and 5V voltages according to actual needs, and automatically reduces power to the lowest level when not in operation; The CPU control unit is used to control the normal operation of the charge and discharge management unit and the PWM control unit, and monitor the working status of the three-stage rectification topology, hierarchical protection circuit and high-precision acquisition circuit in real time through the built-in intelligent monitoring algorithm; it communicates with the main CPU of the power distribution terminal through the RS485 interface, and uploads at least the battery charge and discharge status, capacitor charge and discharge status, PWM working status, capacitor voltage, battery voltage and DC380V output voltage.

[0009] According to a multifunctional low-power distribution terminal power supply system provided by the present invention, the three-stage rectification topology structure includes an input buffer stage, an adaptive synchronous rectification stage and a multi-modal filter output stage; wherein, the input buffer stage adopts a low-impedance π-type LC filter network, and the inductor L1 and the capacitors C1 and C2 constitute a third-order passive filter; the adaptive synchronous rectification stage adopts a bridge rectification structure composed of dual N-channel MOSFETs Q1 and Q2 in parallel, and integrates a zero voltage detection ZVD circuit and an adaptive drive circuit; the multi-modal filter output stage adopts a CLC-type composite filter network.

[0010] According to a multifunctional low-power distribution terminal power supply system provided by the present invention, the low-impedance π-type LC filter network includes a third-order passive filter composed of an inductor L1 and capacitors C1 and C2, wherein L1 adopts a nanocrystalline magnetic core to reduce high-frequency loss, and capacitors C1 and C2 are selected from X7R multilayer ceramic capacitors, which are implemented by the following formula: The cutoff frequency is configured to 1 / 5 of the PWM fundamental frequency to achieve primary suppression of high-frequency harmonics in the PWM output signal. At the same time, the input impedance is matched to 50Ω to improve signal transmission efficiency.

[0011] According to a multifunctional low-power distribution terminal power supply system provided by the present invention, the zero voltage detection ZVD circuit monitors the zero crossing point of the AC input voltage in real time through a comparator. Vac ∣≤ Vth The adaptive drive circuit dynamically adjusts the gate drive voltage based on the input voltage amplitude, and the drive voltage V GS =5 V + Kp ×∣ V ac ∣, Kp is a gain factor of 0.1V / V, making the MOSFET on-resistance R DS(on) = R 0+ Kr ×( V GS -5 V ) 2It decreases nonlinearly with the driving voltage.

[0012] According to a multifunctional low-power distribution terminal power supply system provided by the present invention, the CLC type composite filter network includes an inductor L2, capacitors C3 and C4, the inductor L2 is an amorphous alloy core inductor, and the capacitors C3 and C4 are thin film capacitors, which are implemented by the following formula: Among them, (C eq =C3C4 / (C3+C4)) configures the resonant frequency to be 1 / 10 of the PWM carrier frequency, and combines it with the parallel RC absorption branch to suppress high-frequency spikes, making the output voltage ripple less than 0.5%.

[0013] According to a multifunctional low-power distribution terminal power supply system provided by the present invention, the hierarchical protection circuit includes an overcurrent protection module, an overvoltage protection module, a fault diagnosis module, a hardware comparator array and a multi-stage power switch. The overcurrent protection module adopts a dual-loop monitoring structure. The main loop collects the output current in real time through the Hall current sensor, and the secondary loop detects the conduction voltage drop of the rectifier MOSFET. V DS = I o × R DS(on) Perform redundancy check; when any loop detects I o ≥1.2 Irated When the overcurrent / overvoltage signal is detected, the hardware comparator outputs a protection signal within a predetermined time; the overvoltage protection module adopts a three-level threshold protection mechanism, and monitors the output voltage in real time through a high-precision resistor voltage divider network; the fault diagnosis module adopts a coded fault indication circuit, and encodes the overcurrent / overvoltage signal into a 4-bit binary code through a multiplexer, which is input into the CPU control unit after optical coupling isolation.

[0014] According to a multifunctional low-power distribution terminal power supply system provided by the present invention, the three-level threshold protection mechanism includes: Warning threshold: triggers the PWM frequency reduction instruction of the CPU control unit, causing the output voltage to softly decrease at a rate of 500V / ms; Current limiting threshold: The CPU control unit outputs a PWM blocking signal and simultaneously connects the discharge branch. The power resistor R = 100Ω and the parallel IGBT form an active discharge circuit. Hard shutdown threshold: Directly drives the power relay to cut off the main circuit. Manual reset is required after the fault is cleared to achieve accurate matching of fault level and protection action.

[0015] According to a multifunctional, low-power distribution terminal power supply system provided by the present invention, the high-precision acquisition circuit includes a voltage acquisition channel and a current acquisition channel. The voltage acquisition channel adopts a cascade structure of a three-stage programmable gain amplifier (PGA) and a Σ-Δ ADC. The PGA gain is dynamically configured through the SPI interface of the CPU control unit. Combined with the built-in digital filter of the ADC, the full range of input range from ±5V to ±31.25mV is achieved. The current acquisition channel adopts a high-precision isolation op amp AMC1301 and a differential sample-and-hold circuit to convert the millivolt output signal of the Hall current sensor into a differential voltage. After synchronous acquisition by the ADC, the actual current value is calculated. The actual current value is calculated using the following formula:

[0016] Among them, G iso =8.2 is the gain of the isolated operational amplifier, G adc is the ADC gain, S H =200mV / A is the sensor sensitivity.

[0017] According to the multifunctional low-power distribution terminal power supply system provided by the present invention, during the capacitor charging process, a fuzzy logic controller first receives capacitor voltage monitoring data from a CPU control unit, and then dynamically adjusts the output power of the PWM control unit based on a preset fuzzy rule base to achieve fast and safe charging of the capacitor. The input variables of the fuzzy logic controller are the deviation between the capacitor voltage and the preset voltage threshold and the deviation change rate, and the output variable is the duty cycle adjustment of the PWM control unit. The specific adjustment formula is: D adjust = f fuzzy ( V cap - V threshold , d Vcap / d t ) in, D adjust Indicates the adjustment amount of PWM duty cycle, V cap Indicates the real-time voltage of the capacitor. V threshold Indicates the preset voltage threshold, d Vcap / d t represents the rate of change of capacitor voltage, f fuzzyRepresents the mapping function of the fuzzy logic controller.

[0018] According to a multifunctional low-power distribution terminal power supply system provided by the present invention, a dynamic threshold adjustment strategy is adopted for battery charge and discharge management. The battery charge and discharge thresholds are dynamically adjusted according to the battery's real-time state of charge (SOC), battery temperature, and load demand. When the battery charge is lower than a preset low threshold, capacitors are preferentially used for power supply and the battery charging process is initiated. When the battery charge is higher than a preset high threshold, the algorithm limits battery charging to prevent overcharging. At the same time, during the battery discharge process, the discharge rate is dynamically adjusted according to the load demand. The implementation formula is: SOC threshold = g (SOC current , T battery , P load ) Among them, SOC threshold Indicates the dynamic battery charge and discharge threshold, SOC current Indicates the real-time battery level. T battery Indicates the battery temperature, P load represents the load demand, g A mapping function representing a dynamic threshold adjustment strategy.

[0019] It can be seen that compared with the prior art, the present invention has the following beneficial effects: 1. The charge and discharge management unit of the present invention integrates an intelligent charge and discharge control algorithm based on a fuzzy logic control algorithm combined with a dynamic threshold adjustment strategy, achieving precise management of the capacitor charging process and the battery charging and discharging process. When the capacitor voltage is insufficient, it can automatically switch to the battery discharge mode to provide startup power, ensuring that the system can operate stably under various operating conditions. At the same time, the intelligent algorithm dynamically adjusts the charge and discharge parameters, avoiding unnecessary energy loss, improving energy utilization efficiency, effectively extending the service life of the battery and capacitor, and reducing the maintenance and replacement costs of the system.

[0020] 2. The PWM control unit of this invention utilizes pulse-width modulation technology, enabling flexible output voltages of 380V and 5V based on actual needs. This multi-voltage output capability allows the power supply system to adapt to different types of power distribution terminal equipment without the need for additional voltage conversion devices. This simplifies the system architecture, improves system integration and compatibility, and provides strong support for the diverse applications of power distribution terminal equipment. The PWM control unit automatically reduces power to the minimum level when not in operation, further reducing energy consumption in standby or idle states, maximizing energy utilization, and helping to reduce the operating costs of the entire power distribution terminal system.

[0021] 3. The CPU control unit of this invention incorporates an intelligent monitoring algorithm that monitors the operating status of the three-stage rectification topology, hierarchical protection circuitry, and high-precision data acquisition circuitry in real time. This real-time monitoring of these key components enables timely identification of potential problems and potential faults, enabling proactive preventative measures to address them and prevent further escalation. This ensures the power supply system maintains stable and reliable operation, thereby improving the overall reliability and availability of the power distribution terminal system.

[0022] 4. The three-stage rectifier topology of the present invention includes an input buffer stage, an adaptive synchronous rectifier stage, and a multimodal filter output stage. The input buffer stage effectively buffers input voltage fluctuations, reducing the impact on subsequent circuits. The adaptive synchronous rectifier stage automatically adjusts rectification parameters based on input voltage and load conditions, improving rectification efficiency. The multimodal filter output stage performs multi-stage filtering on the output voltage, effectively reducing output voltage ripple and noise, providing high-quality DC power to distribution terminal equipment and improving operational stability and performance.

[0023] 5. The hierarchical protection circuit of the present invention includes an overcurrent protection module, an overvoltage protection module, a fault diagnosis module, a hardware comparator array and a multi-stage power switch. The overcurrent protection module adopts a dual-loop monitoring structure. The primary loop collects the output current in real time through a Hall current sensor, and the secondary loop performs redundancy verification by detecting the conduction voltage drop of the rectifier MOSFET. When any loop detects an overcurrent, the hardware comparator can quickly output a protection signal within a predetermined time to ensure that the system can cut off the circuit in time in the event of an overcurrent to avoid equipment damage.

[0024] 6. The voltage acquisition channel of the present invention can accurately obtain voltage information at each key node in the power supply system, providing reliable data support for the system's intelligent monitoring and fault diagnosis. The current acquisition channel features high precision, high isolation, and strong anti-interference capabilities, effectively preventing the impact of external interference on current acquisition results, ensuring the accuracy and reliability of the collected current data, and providing precise current information for the system's charge and discharge management and power control.

[0025] 7. During the capacitor charging process, the fuzzy logic-based control method can adaptively adjust the charging power according to the real-time charging state of the capacitor, avoiding the problems of overcharging or undercharging that may occur in traditional charging methods, and improving the efficiency and safety of capacitor charging. For battery charge and discharge management, a dynamic threshold adjustment strategy is adopted to dynamically adjust the battery charge and discharge thresholds according to the battery's real-time state of charge (SOC), battery temperature, and load demand, effectively avoiding the impact of deep discharge on battery life. At the same time, during the battery discharge process, the discharge rate is dynamically adjusted according to the load demand, ensuring that the battery can reasonably release energy while meeting the load demand, thereby improving the battery's energy utilization efficiency.

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of an embodiment of a multifunctional low-power distribution terminal power supply system of the present invention.

[0028] Figure 2 It is a schematic diagram of a three-stage rectifier topology structure in an embodiment of a multifunctional low-power distribution terminal power supply system of the present invention.

[0029] Figure 3 It is a schematic diagram of a hierarchical protection circuit in an embodiment of a multifunctional low-power distribution terminal power supply system of the present invention.

[0030] Figure 4 It is a schematic diagram of a high-precision data acquisition circuit in an embodiment of a multifunctional low-power distribution terminal power supply system of the present invention. DETAILED DESCRIPTION

[0031] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0032] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0033] See also Figure 1This embodiment provides a multifunctional low-power distribution terminal power supply system, including: The filter and rectifier unit is used to filter and rectify the input voltage and output DC voltage to ensure that the entire power module operates stably with low power consumption; The charge and discharge management unit integrates an intelligent charge and discharge control algorithm to manage the charging process of the capacitor and the battery. When the capacitor voltage is insufficient, it switches to battery discharge mode to provide starting power. The intelligent charge and discharge control algorithm is based on a combination of fuzzy logic control algorithm and dynamic threshold adjustment strategy. The PWM control unit uses pulse width modulation technology to output 380V and 5V voltages according to actual needs, and automatically reduces power to the lowest level when not in operation; The CPU control unit is used to control the normal operation of the charge and discharge management unit and the PWM control unit, and monitor the working status of the three-stage rectification topology, hierarchical protection circuit and high-precision acquisition circuit in real time through the built-in intelligent monitoring algorithm; it communicates with the main CPU of the power distribution terminal through the RS485 interface, and uploads at least the battery charge and discharge status, capacitor charge and discharge status, PWM working status, capacitor voltage, battery voltage and DC380V output voltage.

[0034] In this embodiment, if Figure 2 As shown in FIG, the three-stage rectifier topology includes an input buffer stage, an adaptive synchronous rectifier stage, and a multi-mode filter output stage; wherein, the input buffer stage adopts a low-impedance π-type LC filter network, and the inductor L1 and the capacitors C1 and C2 form a third-order passive filter; the adaptive synchronous rectifier stage adopts a bridge rectifier structure composed of dual N-channel MOSFETs Q1 and Q2 in parallel, and integrates a zero voltage detection ZVD circuit and an adaptive drive circuit; the multi-mode filter output stage adopts a CLC type composite filter network.

[0035] Specifically, the low-impedance π-type LC filter network includes a third-order passive filter composed of an inductor L1 and capacitors C1 and C2. L1 uses a nanocrystalline magnetic core to reduce high-frequency loss, and capacitors C1 and C2 use X7R multilayer ceramic capacitors. It is implemented by the following formula: The cutoff frequency is configured to 1 / 5 of the PWM fundamental frequency to achieve primary suppression of high-frequency harmonics in the PWM output signal. At the same time, the input impedance is matched to 50Ω to improve signal transmission efficiency.

[0036] Specifically, the zero voltage detection ZVD circuit monitors the AC input voltage zero point in real time through a comparator. Vac ∣≤ Vth ( VthThe MOSFET generates a synchronous trigger signal when the hysteresis threshold is 200mV, ensuring that the MOSFET is turned on before the body diode is turned on, eliminating reverse recovery loss; the adaptive drive circuit dynamically adjusts the gate drive voltage based on the input voltage amplitude. V GS =5 V + Kp ×∣ Vac ∣, Kp The gain factor is 0.1V / V, making the MOSFET on-resistance R DS(on) = R 0+ Kr ×( V GS -5 V ) 2 With the nonlinear decrease of driving voltage, R0=15mΩ, Kr=0.3mΩ / V 2 .

[0037] Specifically, the CLC composite filter network includes inductor L2 and capacitors C3 and C4. Inductor L2 is an amorphous alloy core inductor (inductance 100μH, equivalent series resistance <5mΩ), and capacitors C3 and C4 are thin film capacitors (capacitance 47μF, equivalent series resistance <2mΩ). It is implemented by the following formula: Among them, (C eq =C3C4 / (C3+C4)) configures the resonant frequency to be 1 / 10 of the PWM carrier frequency. Combined with a parallel RC absorption branch (R=10Ω, C=0.1μF), high-frequency spikes are suppressed, reducing the output voltage ripple to <0.5%. This improves the ripple suppression capability by 60% compared to traditional LC filtering solutions.

[0038] In this embodiment, if Figure 3 As shown in the figure, the hierarchical protection circuit adopts an intelligent hierarchical protection architecture based on transient energy monitoring, including an overcurrent protection module, an overvoltage protection module, a fault diagnosis module, a hardware comparator array, and a multi-level power switch, to achieve millisecond-level fault response and differentiated protection strategies. Among them, the overcurrent protection module adopts a dual-loop monitoring structure. The main loop collects the output current in real time through the Hall current sensor, and the secondary loop detects the conduction voltage drop of the rectifier MOSFET. V DS = I o × R DS(on) Perform redundancy check; when any loop detects Io ≥1.2 Irated hour, IratedFor rated current, the hardware comparator outputs a protection signal within a predetermined time (e.g., 80s), which is two orders of magnitude faster than the response speed of traditional software sampling solutions. The overvoltage protection module adopts a three-level threshold protection mechanism, and monitors the output voltage in real time through a high-precision resistor divider network. The fault diagnosis module adopts a coded fault indication circuit, which encodes the overcurrent / overvoltage signal into a 4-bit binary code (0000-1111 corresponds to 16 fault types) through a multiplexer. After optical coupling isolation, it is input into the CPU control unit, which improves the fault location efficiency by 80% compared with the traditional single-signal indication solution.

[0039] Specifically, the three-level threshold protection mechanism includes: Warning threshold (1.05Vout_rated): triggers the PWM frequency reduction instruction of the CPU control unit, causing the output voltage to softly decrease at a rate of 500V / ms; Current limit threshold (1.1Vout_rated): The CPU control unit outputs a PWM blocking signal and simultaneously turns on the discharge branch. The power resistor R = 100Ω and the parallel IGBT form an active discharge circuit. Hard shutdown threshold (1.2Vout_rated): Directly drives the power relay to cut off the main circuit. Manual reset is required after the fault is cleared to achieve accurate matching of fault level and protection action.

[0040] In this embodiment, if Figure 4 As shown in the figure, the high-precision acquisition circuit uses an 18-bit Σ-Δ ADC based on dynamic gain adjustment and a multi-sensor fusion architecture to achieve μV-level voltage accuracy and mA-level current resolution. It includes voltage and current acquisition channels. The voltage acquisition channel uses a three-stage programmable gain amplifier (PGA) and a Σ-Δ ADC cascade structure. The PGA gain (1 / 8 / 64 times) is dynamically configured through the SPI interface of the CPU control unit. Combined with the ADC's built-in digital filter (cutoff frequency 100Hz), it achieves full-scale coverage of the input range from ±5V to ±31.25mV, with an effective number of bits (ENOB) of 16.3 bits, a 36dB improvement in dynamic range compared to traditional fixed-gain solutions. The current acquisition channel uses the high-precision isolation op amp AMC1301 and a differential sample-and-hold circuit to convert the millivolt output signal of the Hall current sensor into a differential voltage. After synchronous acquisition by the ADC, the actual current value is calculated. The actual current value is calculated using the following formula:

[0041] Among them, G iso =8.2 is the gain of the isolated operational amplifier, G adc is the ADC gain, S H =200mV / A is the sensor sensitivity, and the measurement error is <0.02%FS at an ambient temperature of 25℃.

[0042] The hardware structure of this embodiment uses the collaborative innovation of three-stage rectification topology, transient energy monitoring protection, and dynamic gain acquisition technology to enable the power module to achieve the following under DC380V output conditions: Rectification efficiency ≥98.7% (@full load); Fault response time <120μs; Voltage / current measurement accuracy ±0.05%FS; The long-term operation MTBF is greater than 150,000 hours, achieving a generational breakthrough in efficiency, reliability and intelligence compared to existing technical solutions.

[0043] In actual application, the device is turned on, the filter and rectifier units start working, the CPU detects the low capacitor voltage through the charge and discharge management unit, the CPU cuts off the charging of the battery, connects the battery discharge circuit, controls the PWM to start working, and charges the capacitor with high power, taking the AC27V input and maintaining the input of 3W.

[0044] When the capacitor is fully charged, the CPU cuts off the battery's discharge circuit and connects the battery's charging circuit. The charge and discharge circuit charges the battery and controls PWM for minimum power operation, only requiring DC5V and DC380V with extremely low circuit leakage current for supplementation.

[0045] When the load needs to work, the main energy is provided by the capacitor, and after the output is completed, it enters the cycle work after the device is turned on.

[0046] In this embodiment, for the charging process of the capacitor, the capacitor voltage monitoring data from the CPU control unit is first received through the fuzzy logic controller, and then the output power of the PWM control unit is dynamically adjusted according to the preset fuzzy rule base to achieve fast and safe charging of the capacitor.

[0047] The input variables of the fuzzy logic controller are the deviation between the capacitor voltage and the preset voltage threshold and the deviation change rate, and the output variable is the duty cycle adjustment of the PWM control unit. The specific adjustment formula is: D adjust = f fuzzy ( V cap - V threshold , d Vcap / d t ) in, D adjust Indicates the adjustment amount of PWM duty cycle, Vcap Indicates the real-time voltage of the capacitor. V threshold Indicates the preset voltage threshold, d Vcap / d t represents the rate of change of capacitor voltage, f fuzzy Represents the mapping function of the fuzzy logic controller.

[0048] For battery charge and discharge management, a dynamic threshold adjustment strategy is adopted to dynamically adjust the battery charge and discharge thresholds based on the battery's real-time SOC, battery temperature, and load demand. When the battery charge is lower than the preset low threshold, the capacitor is used for power supply and the battery charging process is started. When the battery charge is higher than the preset high threshold, the algorithm limits the battery charging to prevent overcharging. At the same time, during the battery discharge process, the discharge rate is dynamically adjusted according to the load demand. The implementation formula is: SOC threshold = g (SOC current , T battery , P load ) Among them, SOC threshold Indicates the dynamic battery charge and discharge threshold, SOC current Indicates the real-time battery level. T battery Indicates the battery temperature, P load represents the load demand, g A mapping function representing a dynamic threshold adjustment strategy.

[0049] It can be seen that the intelligent charge and discharge management algorithm that combines the fuzzy logic control algorithm with the dynamic threshold adjustment strategy in this embodiment can dynamically adjust the charge and discharge strategy according to the real-time status of the capacitor and battery, realize the refined management of energy, and effectively improve the energy utilization efficiency and reliability of the power module.

[0050] In this embodiment, the CPU control unit adopts an intelligent monitoring algorithm based on multimodal data fusion and dynamic risk assessment, including: Multimodal data fusion engine, which builds a global state perception model of the rectification-protection-collection system through multi-source heterogeneous data fusion and spatiotemporal correlation analysis; A dynamic risk assessment model, based on a hybrid architecture of physical failure models and machine learning predictions, is used to provide accurate and graded early warning of failures. The fault-tolerant control decision maker implements a hierarchical fault-tolerant strategy based on risk assessment results and builds a system-level resilient operation architecture.

[0051] Specifically, the multimodal data fusion engine includes: Data preprocessing layer: Timing alignment: The voltage / current digital signals (sampling rate 10 kSPS) output by the acquisition circuit, the fault coding signal (event-triggered) of the protection circuit, and the MOSFET conduction state signal (frequency 100 kHz) of the rectifier circuit are time-stamped and synchronized. Cubic spline interpolation is used to perform super-resolution reconstruction of low-frequency signals to ensure a timing error of < 1 μs.

[0052] Feature extraction: Extracting conduction losses from rectifier circuits P cond = I o 2 × R DS(on) ( T j );in, T j The junction temperature is monitored by the thermistor and the equivalent series resistance (ESR) drift of the filter capacitor is:

[0053] Extracting joint time-amplitude features of overcurrent / overvoltage events from protection circuits F evt =[ t evt , I peak / V peak ,Δ t rise ]; extract the ADC quantization noise power from the acquisition circuit and express it as:

[0054] Where N is the sampling window length.

[0055] Feature fusion layer: Tensor modeling: constructing a four-dimensional state tensor T∈R 3×4×T×M , where 3 dimensions correspond to rectification / protection / collection circuits, 4 feature channels correspond to electrical quantities, temperature, noise, and time characteristics, T is the time window length (100ms), and M is the number of feature dimensions (8 dimensions).

[0056] Attention weighted fusion: The weight of each feature channel is calculated through the self-attention mechanism, which is expressed as:

[0057] Q / K is the query / key vector, dk is the feature dimension, and the fused feature vector is obtained. Compared with the traditional weighted average method, the feature utilization rate is improved by 37%, which is: Dynamic risk assessment model, including Physical failure prediction sub-model: Capacitor life prediction: Using the Arrhenius model combined with the rain flow counting method, the formula is:

[0058] Where L0 is the reference life, Ea=0.7eV is the activation energy, k is the Boltzmann constant, T0=25℃ is the reference temperature, Nf is the equivalent number of cycles, and n=9 is the Weibull index) to predict the remaining life of the electrolytic capacitor. Lcap <10% Ldesign A level one warning is triggered.

[0059] MOSFET junction temperature prediction: through real-time monitoring of conduction losses Pcond and thermal resistance Rthja , using the formula Tj = Ta + Pcond × Rthja ( Ta is the ambient temperature) to calculate the junction temperature, when Tj When the temperature is >125℃, PWM frequency reduction protection is activated.

[0060] Machine learning prediction sub-model: LSTM-Attention network: input is the fused feature vector F fused , the output is the failure probability in the next 50ms Pfail ( t +Δ t ), the network structure consists of 2 layers of LSTM (hidden layer dimension 64) and 1 layer of self-attention layer, through the formula h t =LSTM(F fused ( t ),h t -1), z t =Attention(h t ) realizes time series feature extraction and key frame focusing, which improves the prediction accuracy by 21% compared with the traditional LSTM model.

[0061] Dynamic threshold generation: Dynamically adjust the fault warning threshold according to the system operating conditions (load rate, ambient temperature). The threshold adjustment formula is: (θ0 is the reference threshold, β=0.3 is the load sensitivity coefficient), achieving differentiated early warning under light load / heavy load conditions.

[0062] Fault-tolerant control decision maker, including: Fault classification mechanism: Level 1 warning (risk value 0.7-0.9): The CPU control unit sends a PWM frequency reduction instruction to the rectifier circuit through the SPI interface (frequency reduction by 30%), and at the same time starts the warning threshold self-calibration process of the protection circuit to reduce the probability of false operation.

[0063] Level 2 alarm (risk value 0.9-1.0): Cut off the power supply circuit for non-critical loads, enable the backup acquisition channel (dual ADC redundant design), and send a fault location data packet (including fault time, circuit number, and feature vector) to the distribution terminal main control unit via the CAN bus.

[0064] Level 3 shutdown (risk value > 1.0): Drives the power relay to disconnect the main circuit within 200μs. Simultaneously, it stores the raw data (sampling rate 100kSPS) from 1s before the fault in ferroelectric memory (FRAM) to support fault recurrence analysis.

[0065] Self-healing control strategy: Rectifier circuit self-healing: When a single MOSFET fault is detected, the faulty transistor drive signal is bypassed through the GPIO pin and the gate drive voltage of the remaining MOSFETs is adjusted to V GS′ = V GS +0.5 V To compensate for the increase in on-resistance and maintain the output power above 85% of the rated value.

[0066] Acquisition circuit self-healing: When the main ADC fails, it automatically switches to the backup ADC and uses the formula: Where V ref is the reference voltage, D is the digital output, and online calibration is performed to restore the measurement error to within ±0.03%FS.

[0067] In summary, the charge-discharge management unit integrates an intelligent charge-discharge control algorithm based on a fuzzy logic control algorithm combined with a dynamic threshold adjustment strategy, achieving precise management of the capacitor charging process and the battery charging and discharging process. When the capacitor voltage is insufficient, it automatically switches to battery discharge mode to provide startup power, ensuring stable system operation under various operating conditions. Furthermore, the intelligent algorithm dynamically adjusts the charge and discharge parameters, avoiding unnecessary energy loss, improving energy efficiency, effectively extending the service life of the battery and capacitor, and reducing system maintenance and replacement costs.

[0068] Furthermore, the PWM control unit utilizes pulse-width modulation technology, enabling flexible output voltages of 380V and 5V based on actual needs. This multi-voltage output capability allows the power supply system to adapt to different types of distribution terminal equipment without the need for additional voltage conversion devices. This simplifies the system architecture, improves system integration and compatibility, and provides strong support for the diverse applications of distribution terminal equipment. The PWM control unit automatically reduces power to the minimum level when not in operation, further reducing energy consumption in standby or idle states, maximizing energy utilization and helping to lower the operating costs of the entire distribution terminal system.

[0069] Furthermore, the CPU control unit incorporates a built-in intelligent monitoring algorithm that provides real-time monitoring of the operating status of the three-stage rectification topology, hierarchical protection circuitry, and high-precision data acquisition circuitry. This real-time monitoring of these critical components enables timely identification of potential problems and potential faults, enabling proactive preventative measures to address them and prevent further escalation. This ensures the power system maintains stable and reliable operation, improving the overall reliability and availability of the distribution terminal system.

[0070] Furthermore, the three-stage rectification topology includes an input buffer stage, an adaptive synchronous rectification stage, and a multi-mode filter output stage. The input buffer stage effectively buffers input voltage fluctuations, reducing the impact on subsequent circuits. The adaptive synchronous rectification stage automatically adjusts rectification parameters based on input voltage and load conditions, improving rectification efficiency. The multi-mode filter output stage performs multi-stage filtering on the output voltage, effectively reducing output voltage ripple and noise, providing high-quality DC power to distribution terminal equipment and improving operational stability and performance.

[0071] Furthermore, the hierarchical protection circuit includes an overcurrent protection module, an overvoltage protection module, a fault diagnosis module, a hardware comparator array and a multi-stage power switch. The overcurrent protection module adopts a dual-loop monitoring structure. The main loop collects the output current in real time through a Hall current sensor, and the secondary loop performs redundant verification by detecting the conduction voltage drop of the rectifier MOSFET. When any loop detects an overcurrent, the hardware comparator can quickly output a protection signal within a predetermined time to ensure that the system can cut off the circuit in time in an overcurrent situation to avoid equipment damage.

[0072] Furthermore, the voltage acquisition channel accurately captures voltage information at key nodes in the power supply system, providing reliable data support for intelligent monitoring and fault diagnosis. The current acquisition channel features high precision, high isolation, and strong anti-interference capabilities, effectively preventing external interference from affecting current acquisition results. This ensures accurate and reliable current data, providing precise current information for the system's charge and discharge management and power control.

[0073] Furthermore, during the capacitor charging process, a fuzzy logic-based control method can adaptively adjust the charging power according to the capacitor's real-time charging state, avoiding the overcharging or undercharging problems that may occur in traditional charging methods, and improving the efficiency and safety of capacitor charging. For battery charge and discharge management, a dynamic threshold adjustment strategy is adopted to dynamically adjust the battery's charge and discharge thresholds based on the battery's real-time state of charge (SOC), battery temperature, and load demand, effectively avoiding the impact of deep discharge on battery life. At the same time, during the battery discharge process, the discharge rate is dynamically adjusted according to the load demand, ensuring that the battery can reasonably release energy while meeting the load demand, thereby improving the battery's energy utilization efficiency.

[0074] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0075] The above embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and replacements made by technicians in this field on the basis of the present invention fall within the scope of protection required by the present invention.

Claims

1. A multifunctional low-power distribution terminal power supply system, characterized in that: include: The filter and rectifier unit is used to filter and rectify the input voltage and output DC voltage to ensure that the entire power module operates stably with low power consumption; The charge and discharge management unit integrates an intelligent charge and discharge control algorithm to manage the charging process of the capacitor and the battery. When the capacitor voltage is insufficient, it switches to battery discharge mode to provide starting power. The intelligent charge and discharge control algorithm is based on a combination of fuzzy logic control algorithm and dynamic threshold adjustment strategy. The PWM control unit uses pulse width modulation technology to output 380V and 5V voltages according to actual needs, and automatically reduces power to the lowest level when not in operation; The CPU control unit is used to control the normal operation of the charge and discharge management unit and the PWM control unit, and monitor the working status of the three-stage rectification topology, hierarchical protection circuit and high-precision acquisition circuit in real time through the built-in intelligent monitoring algorithm; it communicates with the main CPU of the power distribution terminal through the RS485 interface, and uploads at least the battery charge and discharge status, capacitor charge and discharge status, PWM working status, capacitor voltage, battery voltage and DC380V output voltage.

2. The system according to claim 1, wherein: The three-stage rectification topology includes an input buffer stage, an adaptive synchronous rectification stage, and a multi-modal filtering output stage. The input buffer stage adopts a low-impedance π-type LC filtering network, and the inductor L1 and the capacitors C1 and C2 form a third-order passive filter. The adaptive synchronous rectification stage adopts a bridge rectification structure composed of dual N-channel MOSFETs Q1 and Q2 in parallel, and integrates a zero voltage detection ZVD circuit and an adaptive drive circuit. The multi-modal filtering output stage adopts a CLC composite filtering network.

3. The system according to claim 2, characterized in that: The low-impedance π-type LC filter network includes a third-order passive filter composed of an inductor L1 and capacitors C1 and C2. L1 uses a nanocrystalline magnetic core to reduce high-frequency loss, and capacitors C1 and C2 use X7R multilayer ceramic capacitors. The following formula is used to implement the filter: The cutoff frequency is configured to 1 / 5 of the PWM fundamental frequency to achieve primary suppression of high-frequency harmonics in the PWM output signal. At the same time, the input impedance is matched to 50Ω to improve signal transmission efficiency.

4. The system according to claim 2, wherein: The zero voltage detection ZVD circuit monitors the AC input voltage zero point in real time through a comparator. V ac ∣≤ V th The adaptive drive circuit dynamically adjusts the gate drive voltage based on the input voltage amplitude, and the drive voltage V GS =5 V + Kp ×∣ V ac ∣, Kp is a gain factor of 0.1V / V, making the MOSFET on-resistance R DS(on) = R 0+ Kr ×( V GS -5 V ) 2 It decreases nonlinearly with the driving voltage.

5. The system according to claim 2, wherein: The CLC type composite filter network includes an inductor L2, capacitors C3 and C4, where the inductor L2 is an amorphous alloy core inductor and the capacitors C3 and C4 are thin film capacitors, and is implemented by the following formula: Among them, (C eq =C3C4 / (C3+C4)) configures the resonant frequency to be 1 / 10 of the PWM carrier frequency, and combines it with the parallel RC absorption branch to suppress high-frequency spikes, making the output voltage ripple less than 0.5%.

6. The system according to claim 1, wherein: The hierarchical protection circuit includes an overcurrent protection module, an overvoltage protection module, a fault diagnosis module, a hardware comparator array and a multi-stage power switch. The overcurrent protection module adopts a dual-loop monitoring structure. The main loop collects the output current in real time through the Hall current sensor, and the secondary loop detects the conduction voltage drop of the rectifier MOSFET. V DS = I o × R DS(on) Perform redundancy check; when any loop detects I o ≥1.2 Irated When the overcurrent / overvoltage signal is detected, the hardware comparator outputs a protection signal within a predetermined time; the overvoltage protection module adopts a three-level threshold protection mechanism, and monitors the output voltage in real time through a high-precision resistor voltage divider network; the fault diagnosis module adopts a coded fault indication circuit, and encodes the overcurrent / overvoltage signal into a 4-bit binary code through a multiplexer, which is input into the CPU control unit after optical coupling isolation.

7. The system according to claim 6, characterized in that: The three-level threshold protection mechanism includes: Warning threshold: triggers the PWM frequency reduction instruction of the CPU control unit, causing the output voltage to softly decrease at a rate of 500V / ms; Current limiting threshold: The CPU control unit outputs a PWM blocking signal and simultaneously connects the discharge branch. The power resistor R = 100Ω and the parallel IGBT form an active discharge circuit. Hard shutdown threshold: Directly drives the power relay to cut off the main circuit. Manual reset is required after the fault is cleared to achieve accurate matching of fault level and protection action.

8. The system according to claim 1, wherein: The high-precision acquisition circuit includes a voltage acquisition channel and a current acquisition channel. The voltage acquisition channel uses a three-stage programmable gain amplifier (PGA) and a Σ-Δ ADC cascade structure. The PGA gain is dynamically configured through the SPI interface of the CPU control unit. Combined with the ADC's built-in digital filter, it achieves full-scale coverage of the input range from ±5V to ±31.25mV. The current acquisition channel uses a high-precision isolation op amp AMC1301 and a differential sample-and-hold circuit to convert the millivolt output signal of the Hall current sensor into a differential voltage. After synchronous acquisition by the ADC, the actual current value is calculated. The actual current value is calculated using the following formula: Among them, G iso =8.2 is the gain of the isolated operational amplifier, Gadc is the ADC gain, S H =200mV / A is the sensor sensitivity.

9. The system according to claim 1, wherein: For the capacitor charging process, the fuzzy logic controller first receives the capacitor voltage monitoring data from the CPU control unit, and then dynamically adjusts the output power of the PWM control unit according to the preset fuzzy rule base to achieve fast and safe charging of the capacitor; The input variables of the fuzzy logic controller are the deviation between the capacitor voltage and the preset voltage threshold and the deviation change rate, and the output variable is the duty cycle adjustment of the PWM control unit. The specific adjustment formula is: D adjust = f fuzzy ( V cap - V threshold ， d Vcap / d t ) in, D adjust Indicates the adjustment amount of PWM duty cycle, V cap Indicates the real-time voltage of the capacitor. V threshold Indicates the preset voltage threshold, d Vcap / d t represents the rate of change of capacitor voltage, f fuzzy Represents the mapping function of the fuzzy logic controller.

10. The system according to claim 9, characterized in that: For battery charge and discharge management, a dynamic threshold adjustment strategy is adopted to dynamically adjust the battery charge and discharge thresholds based on the battery's real-time SOC, battery temperature, and load demand. When the battery charge is lower than the preset low threshold, the capacitor is used for power supply and the battery charging process is started. When the battery charge is higher than the preset high threshold, the algorithm limits the battery charging to prevent overcharging. At the same time, during the battery discharge process, the discharge rate is dynamically adjusted according to the load demand. The implementation formula is: SOCIETY threshold = g (SOC current , T battery , P load ) Among them, SOC threshold Indicates the dynamic battery charge and discharge threshold, SOC current Indicates the real-time battery level. T battery Indicates the battery temperature, P load represents the load demand, g A mapping function representing a dynamic threshold adjustment strategy.

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