Distributed dc power supply system based on industrial logistics robot

Abstract

The present application relates to the distributed direct current power supply system based on industrial logistics robot, and relates to the power supply system technical field, including the distributed arrangement direct current power supply unit;The present application solves the problem of large voltage drop of long distance power supply and insufficient power supply of multiple point power consumption through the power supply mode of the distributed direct current power supply unit nearby, the active support based on voltage change rate prediction and the fluctuation hedging of the reverse current superposition of adjacent units, effectively inhibit the bus voltage fluctuation caused by load impact current and high frequency ripple, the coupling of power supply capacity and motion planning makes the robot avoid the weak power supply area in the planning stage, the actual available capacity evaluation based on health state makes the power distribution dynamically adjust with the unit degradation degree, avoids the accelerated failure caused by the degradation to bear excess power, the feedforward compensation based on the expected power demand eliminates the voltage drop caused by the power supply response lag when the load arrives, and the automatic compensation of the automatic exit of the fault guarantees the continuous and reliable operation of the system under single point fault.

Description

Technical Field

[0001] This invention relates to the field of power supply system technology, and in particular to a distributed DC power supply system based on industrial logistics robots. Background Technology

[0002] Industrial logistics robots are computer-controlled robots with functions such as mobility, automatic navigation, multi-sensor control, and network interaction. Their primary application in actual production is material handling. Their unique advantages in automation, flexibility, and safety make them the optimal choice for intelligent and automated logistics. With the rapid development of warehouse automation and intelligent logistics, industrial logistics robots are evolving towards higher power, higher density, and cluster collaboration. The driving power of a single AGV / AMR has increased from the early 200W-750W to 1.5kW-3kW or even higher. Multiple robots need to work collaboratively in the same area, creating complex scenarios with multiple power consumption points. Currently, industrial AGVs are powered by onboard battery packs, replenished through charging piles or battery swapping stations; contact power supply methods use conductive contacts or sliding contact lines to draw power from the power supply track; and non-contact power supply methods use magnetic resonance or electromagnetic induction technology to achieve wireless energy transmission. The following shortcomings still exist in the practical application of industrial logistics robots: Industrial logistics robots have high load power and wide movement range. Low-voltage power supply with long power lines results in significant voltage drop, leading to large voltage fluctuations at the load end. Meanwhile, centralized power supply cannot meet the simultaneous power needs of multiple robots in different locations, as power supply capacity is limited by the power limit of a single power source. While existing solutions reduce power supply distance through distributed deployment, there is a lack of proactive coordination mechanisms between DC power supply units based on load power demand prediction. When the moving load at a certain point suddenly increases, the bus voltage can still experience a momentary drop. Existing solutions do not couple power supply capacity information with robot motion planning, potentially causing insufficient power supply if the robot enters an area with weak power supply. Furthermore, existing solutions lack an assessment mechanism for the health degradation of the DC power supply units themselves; degraded units may bear excessive power, affecting the overall reliability of the system.

[0003] To address the aforementioned technical shortcomings, a solution is proposed. Summary of the Invention

[0004] This invention adopts the following technical solution: a distributed DC power supply system based on industrial logistics robots, comprising: The distributed power supply module includes multiple DC power supply units distributed along the power supply line. Each DC power supply unit is connected to the DC bus and is used to convert the input power into DC output and supply power to the industrial logistics robot load via the DC bus. The power supply motion planning module is used to generate robot path planning schemes under power supply capacity constraints by using the remaining capacity information of each DC power supply unit as path planning constraints, so that each industrial logistics robot can avoid power-limited areas. The instantaneous power offset module is used to collect the voltage change rate of the local bus in real time, predict the change trend of load power demand based on the voltage change rate, actively adjust the output current before the bus voltage drops, and when any output current has high frequency fluctuations, the adjacent DC power supply unit superimposes the reverse current component into its own output. The health capacity reconfiguration module is used to assess the actual available capacity of the DC power supply unit based on its cumulative operating time, historical output power fluctuation amplitude and temperature rise rate, calculate the remaining capacity ratio based on the actual available capacity and allocate supplementary power. The power feedforward compensation module is used to adjust the output current of each DC power supply unit in advance according to the expected power demand of each industrial logistics robot in the future time window.

[0005] Furthermore, the remaining capacity information of each DC power supply unit is used as a path planning constraint to generate a robot path planning scheme under power supply capacity constraints. The specific process is as follows: The remaining capacity ratio and health status assessment value of each DC power supply unit are obtained and mapped to the location on the power supply line to the field map coordinate system to generate a power supply capacity distribution map. The current location, target task, and predetermined movement path of each industrial logistics robot are obtained. Multiple path points are sampled at preset distance intervals along the predetermined movement path of each robot. The remaining capacity ratio of each path point is queried according to the power supply capacity distribution map. The expected power demand of each robot along the predetermined movement path is calculated. Path points in each path where the remaining capacity is insufficient to meet the corresponding expected power demand are marked as power supply-limited points. For robots whose predetermined movement path passes through power-limited points, search for alternative paths to avoid power-limited points, and use the alternative paths as the planned paths when they exist. When there is no alternative path, calculate the estimated time when the robot will reach the power-limited point, query the predicted remaining capacity of the power-limited point at the estimated time, and when the predicted remaining capacity is sufficient to meet the expected power demand, adjust the robot's moving speed so that it can reach the power-limited point at the estimated time. When multiple robots pass through the same power supply service area within the same time window and the remaining capacity of the DC power supply unit is insufficient to meet the expected power demand of multiple robots simultaneously, calculate the estimated time when each robot will arrive at the service area, and adjust the moving speed and path of at least one robot so that multiple robots enter the service area of ​​the same DC power supply unit at staggered times.

[0006] Furthermore, based on the voltage change rate, the load power demand trend is predicted, and the output current is actively adjusted before a bus voltage drop occurs. The specific process is as follows: Each DC power supply unit continuously collects the voltage value of the local bus at a preset sampling period, calculates the voltage difference between the current sampling period and the previous sampling period, and uses the ratio of the voltage difference to the sampling period as the voltage change rate of the local bus. The voltage change rate is compared with a preset change rate threshold. When the voltage change rate is negative and the absolute value exceeds the preset change rate threshold, it is determined that the load power demand is about to increase. The DC power supply unit increases its own output current in advance before the bus voltage drops below the target value. When the voltage change rate is positive and exceeds the preset change rate threshold, it is determined that the load power demand is about to decrease, and this DC power supply unit reduces its own output current in advance. When multiple DC power supply units simultaneously detect the same rate of voltage change, each DC power supply unit exchanges voltage change rate information through the communication bus and coordinates to adjust the output current according to the preset power allocation ratio, so that the voltage of the DC bus remains stable during the change of load power demand.

[0007] Furthermore, when any output current experiences high-frequency fluctuations, a reverse current component is superimposed on its own output by the adjacent DC power supply unit. The specific process is as follows: When the output current of the first DC power supply unit exhibits high-frequency fluctuations exceeding a preset frequency threshold, it sends fluctuation information, including fluctuation frequency, fluctuation amplitude, and fluctuation phase, to the adjacent second DC power supply unit via the communication bus. After receiving the fluctuation information, the second DC power supply unit superimposes a compensation current component into its output current. The frequency of the compensation current component is the same as the fluctuation frequency, the amplitude matches the fluctuation amplitude, and the phase is opposite to the fluctuation phase. This causes the output current fluctuation of the first DC power supply unit and the compensation current component of the second DC power supply unit to cancel each other out after being superimposed on the DC bus, thereby reducing the high-frequency fluctuation amplitude of the bus current.

[0008] Furthermore, the actual usable capacity of the DC power supply unit is assessed based on its cumulative operating time, historical output power fluctuation range, and temperature rise rate, as follows; Each DC power supply unit records its cumulative running time through an internal timer, records the fluctuation range of output power during historical operation through a power detection circuit, and collects the temperature of power devices in real time through a temperature sensor and calculates the temperature rise rate per unit time. Each DC power supply unit assesses its own health status based on its cumulative operating time, historical output power fluctuation range, and temperature rise rate. Each DC power supply unit corrects its rated output current based on its own health status assessment value, and uses the corrected current value as its actual usable capacity. Each DC power supply unit uses the ratio of the difference between its actual available capacity and the current output current to its actual available capacity as its remaining capacity ratio, and sends the remaining capacity ratio and health status assessment value to other DC power supply units through the communication bus.

[0009] Furthermore, the remaining capacity proportion is calculated based on the actual available capacity, and supplementary power is allocated accordingly. The specific process is as follows: When a power shortage occurs on the DC bus and needs to be replenished, each DC power supply unit calculates its own power and assigns weights accordingly. Power deficit includes the total power demand of all industrial logistics robots exceeding the sum of the actual available capacity of all DC power supply units, the failure of any DC power supply unit to go out of operation, resulting in a reduction in the total supplied power, and a decrease in the health status assessment value of any DC power supply unit, resulting in a reduction in its actual available capacity and a reduction in the total available supplied power. Each DC power supply unit shares the supplementary power according to its power allocation weight. When the health status assessment value of any DC power supply unit is lower than the preset health threshold, the power allocation weight of the DC power supply unit is reduced and a maintenance reminder is generated.

[0010] Furthermore, the output current of each DC power supply unit is adjusted in advance according to the expected power demand of each industrial logistics robot within a future time window. The specific process is as follows: Obtain the current location, planned movement path, and expected power requirements of each industrial logistics robot. The expected power requirements include the predicted power requirements of each robot at each time point within a future time window. Based on the predetermined movement path of each robot, the service range of the DC power supply unit where each robot is located at each time point is determined. The expected power demand of each robot is assigned according to the service range of the DC power supply unit, and the expected load power of each DC power supply unit at each time point in the future time window is obtained. The expected load power of each DC power supply unit is sent to the corresponding DC power supply unit. Each DC power supply unit adjusts its output current in advance so that the current on the DC bus reaches a level that matches the expected load power before the robot arrives.

[0011] Furthermore, it also includes automatic exit of faulty units and anti-backflow modules, the specific process of which is as follows: A reverse current protection circuit is set at the output terminal of each DC power supply unit. The reverse current protection circuit includes a unidirectional conducting element connected in series between the positive output terminal of the DC power supply unit and the DC bus, and a reverse current detection element connected in parallel at the output terminal of the DC power supply unit. Each of the DC power supply units collects its own output voltage, output current and internal power device temperature in real time, and compares them with the corresponding preset range; When the output voltage, output current, or internal power device temperature of any DC power supply unit exceeds the corresponding preset range, and the reverse current detection element detects that the reverse current exceeds the preset reverse current threshold, the DC power supply unit is determined to have malfunctioned and a fault flag is generated. In response to the generation of a fault indicator, the DC power supply unit automatically disconnects from the DC bus and exits operation through a unidirectional conduction element, while the remaining DC power supply units on the DC bus automatically increase their output current to compensate for the power deficit. After a DC power supply unit is taken out of service, it sends a fault notification containing the fault event and the time of the fault to other DC power supply units and the operation and maintenance system via the communication bus, and waits for maintenance before being reconnected.

[0012] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: This distributed DC power supply system for industrial logistics robots solves the problems of large voltage drops during long-distance movement and insufficient power supply at multiple points by providing power to nearby distributed DC power supply units. It eliminates the battery life bottleneck and safety hazards. Based on the active support of voltage change rate prediction and the fluctuation offset of the superposition of reverse current of adjacent units, the power supply response is upgraded from post-compensation to pre-prediction. It effectively suppresses the bus voltage fluctuation caused by load inrush current and high frequency ripple. The coupling of power supply capacity and motion planning allows the robot to avoid weak power supply areas during the planning stage, avoiding the passive situation of discovering insufficient power supply only after arrival. Based on the actual available capacity assessment of the health status, the power distribution is dynamically adjusted according to the degree of unit degradation, avoiding accelerated failure due to degradation bearing excessive power, and extending the overall service life of the system. Feedforward compensation based on expected power demand eliminates the voltage drop caused by the lag in power supply response when the load arrives. Automatic exit and automatic compensation for faults ensure the continuous and reliable operation of the system under single-point failure. Attached Figure Description

[0013] Figure 1 A schematic diagram of the overall external structure of the present invention is shown; Figure 2 A schematic diagram of the power supply motion planning process of the present invention is shown; Figure 3 A schematic diagram of the dynamic capacity analysis process for health status according to the present invention is shown. Detailed Implementation

[0014] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below. Example

[0015] like Figure 1-3 As shown, the distributed DC power supply system based on industrial logistics robots includes: The distributed power supply module includes multiple DC power supply units distributed along the power supply line. Each DC power supply unit is connected to the DC bus and is used to convert the input power into DC output and supply power to the industrial logistics robot load via the DC bus. The power supply motion planning module is used to generate robot path planning schemes under power supply capacity constraints by using the remaining capacity information of each DC power supply unit as path planning constraints, so that each industrial logistics robot can avoid power-limited areas. The instantaneous power offset module is used to collect the voltage change rate of the local bus in real time, predict the change trend of load power demand based on the voltage change rate, actively adjust the output current before the bus voltage drops, and when any output current has high frequency fluctuations, the adjacent DC power supply unit superimposes the reverse current component into its own output. The health capacity reconfiguration module is used to assess the actual available capacity of the DC power supply unit based on its cumulative operating time, historical output power fluctuation amplitude and temperature rise rate, calculate the remaining capacity ratio based on the actual available capacity and allocate supplementary power. The power feedforward compensation module is used to adjust the output current of each DC power supply unit in advance according to the expected power demand of each industrial logistics robot in the future time window.

[0016] This is used to generate a robot path planning scheme under power supply capacity constraints, using the remaining capacity information of each DC power supply unit as the path planning constraint. The specific process is as follows: Specifically, it includes multiple DC power supply units, each of which is distributed along the power supply lines within the working area of ​​the industrial logistics robot. The number and location of each DC power supply unit are determined based on the movement range and power demand of the industrial logistics robot. In areas where the robot moves frequently and the power demand is concentrated, a larger number of DC power supply units 110 are arranged; in areas where the robot moves less and the power demand is dispersed, a smaller number of DC power supply units are arranged. Each DC power supply unit collects its current output current in real time, assesses its health status based on its cumulative running time, historical output power fluctuation range and temperature rise rate, corrects its rated output current with the health status assessment value to obtain the actual usable capacity, and uses the ratio of the difference between the actual usable capacity and the current output current to the actual usable capacity as the proportion of its remaining capacity. The remaining capacity ratio and health status assessment value of each DC power supply unit are obtained and mapped to the location on the power supply line to the field map coordinate system to generate a power supply capacity distribution map. The remaining capacity ratio of the DC power supply unit to which the location point belongs is marked in the power supply capacity distribution map. The current location, target task, and predetermined movement path of each industrial logistics robot are obtained. Multiple path points are sampled at preset distance intervals along the predetermined movement path of each robot. The remaining capacity ratio of each path point is queried according to the power supply capacity distribution map. The expected power demand of each robot along the predetermined movement path is calculated. Path points in each path where the remaining capacity is insufficient to meet the corresponding expected power demand are marked as power supply-limited points. For robots whose predetermined movement path passes through power-limited points, search for alternative paths to avoid power-limited points, and use the alternative paths as the planned paths when they exist. When there is no alternative path, calculate the estimated time when the robot will reach the power-limited point, query the predicted remaining capacity of the power-limited point at the estimated time, and when the predicted remaining capacity is sufficient to meet the expected power demand, adjust the robot's moving speed so that it can reach the power-limited point at the estimated time. When multiple robots pass through the same power supply service area within the same time window and the remaining capacity of the DC power supply unit is insufficient to meet the expected power demand of multiple robots simultaneously, calculate the estimated time when each robot will arrive at the service area, and adjust the moving speed and path of at least one robot so that multiple robots enter the service area of ​​the same DC power supply unit at staggered times.

[0017] Based on the voltage change rate, the load power demand trend is predicted, and the output current is actively adjusted before the bus voltage drop occurs. The specific process is as follows: Each DC power supply unit continuously collects the voltage value of the local bus at a preset sampling period, calculates the voltage difference between the current sampling period and the previous sampling period, and uses the ratio of the voltage difference to the sampling period as the voltage change rate of the local bus. The voltage change rate is compared with a preset change rate threshold. When the voltage change rate is negative and the absolute value exceeds the preset change rate threshold, it is determined that the load power demand is about to increase. The DC power supply unit increases its own output current in advance before the bus voltage drops below the target value. When the voltage change rate is positive and exceeds the preset change rate threshold, it is determined that the load power demand is about to decrease, and this DC power supply unit reduces its own output current in advance. When multiple DC power supply units simultaneously detect the same rate of voltage change, each DC power supply unit exchanges voltage change rate information through the communication bus and coordinates to adjust the output current according to the preset power allocation ratio, so that the voltage of the DC bus remains stable during the change of load power demand.

[0018] When a high-frequency fluctuation occurs in any output current, a reverse current component is superimposed on the output of the adjacent DC power supply unit. The specific process is as follows: When the output current of the first DC power supply unit exhibits high-frequency fluctuations exceeding a preset frequency threshold, it sends fluctuation information, including fluctuation frequency, fluctuation amplitude, and fluctuation phase, to the adjacent second DC power supply unit via the communication bus. After receiving the fluctuation information, the second DC power supply unit superimposes a compensation current component into its output current. The frequency of the compensation current component is the same as the fluctuation frequency, the amplitude matches the fluctuation amplitude, and the phase is opposite to the fluctuation phase. This causes the output current fluctuation of the first DC power supply unit and the compensation current component of the second DC power supply unit to cancel each other out after being superimposed on the DC bus, thereby reducing the high-frequency fluctuation amplitude of the bus current.

[0019] The process is as follows: The actual usable capacity of a DC power supply unit is assessed based on its cumulative operating time, historical output power fluctuation, and temperature rise rate. Each DC power supply unit records its cumulative running time through an internal timer, records the fluctuation range of output power during historical operation through a power detection circuit, and collects the temperature of power devices in real time through a temperature sensor and calculates the temperature rise rate per unit time. Each DC power supply unit assesses its own health status based on cumulative operating time, historical output power fluctuation amplitude, and temperature rise rate. The health status assessment value is inversely correlated with cumulative operating time, historical output power fluctuation amplitude, and temperature rise rate. Specifically, health status assessment values ​​are evaluated as follows:

[0020] Where H0 is the initial health status assessment value (taken as 1.0), Tmax is the preset maximum operating time, Pmax is the preset maximum power fluctuation amplitude, and ΔTmax is the preset maximum temperature rise rate. Each DC power supply unit corrects its rated output current Irated based on its own health status assessment value, and uses the corrected current value as its actual usable capacity Iactual=Irated×H; Each DC power supply unit uses the ratio of the difference between its actual available capacity and the current output current to its actual available capacity as its remaining capacity ratio, and sends the remaining capacity ratio and health status assessment value to other DC power supply units through the communication bus.

[0021] The remaining capacity proportion is calculated and supplementary power is allocated based on the actual available capacity. The specific process is as follows: When a power shortage occurs on the DC bus and needs to be replenished, each DC power supply unit calculates its own power and assigns weights accordingly.

[0022] Where Wi is the power allocation weight of the i-th DC power supply unit, Ri is the remaining capacity ratio of the i-th DC power supply unit, Hi is the health status assessment value of the i-th DC power supply unit, N is the total number of DC power supply units, each DC power supply unit 110 shares the supplementary power according to the power allocation weight, and i and j are the DC power supply unit indices.

[0023] Power deficit includes the total power demand of all industrial logistics robots exceeding the sum of the actual available capacity of all DC power supply units, the failure of any DC power supply unit to go out of operation, resulting in a reduction in the total supplied power, and a decrease in the health status assessment value of any DC power supply unit, resulting in a reduction in its actual available capacity and a reduction in the total available supplied power. Each DC power supply unit shares the supplementary power according to its power allocation weight, so that DC power supply units with good health and sufficient remaining capacity bear more supplementary power, while DC power supply units with deteriorating health or insufficient remaining capacity bear less supplementary power. When the health status assessment value of any DC power supply unit is lower than the preset health threshold, the power allocation weight of the DC power supply unit is reduced and a maintenance reminder is generated.

[0024] The process is as follows: This is used to adjust the output current of each DC power supply unit in advance based on the expected power demand of each industrial logistics robot within a future time window. Obtain the current location, planned movement path, and expected power requirements of each industrial logistics robot. The expected power requirements include the predicted power requirements of each robot at each time point within a future time window. Based on the predetermined movement path of each robot, the service range of the DC power supply unit where each robot is located at each time point is determined. The expected power demand of each robot is assigned according to the service range of the DC power supply unit, and the expected load power of each DC power supply unit at each time point in the future time window is obtained. The expected load power of each DC power supply unit is sent to the corresponding DC power supply unit. Each DC power supply unit adjusts its output current in advance so that the current on the DC bus reaches a level that matches the expected load power before the robot arrives.

[0025] This invention adjusts the output current of each DC power supply unit in advance according to the expected power demand of each industrial logistics robot in the future time window, so that the current on the DC bus reaches a level that matches the expected load power before the robot arrives, realizing feedforward compensation of the power supply current to the load demand and eliminating voltage drop caused by power supply response lag when the load arrives.

[0026] It also includes an automatic exit mechanism for faulty units and a backflow prevention module, the specific process of which is as follows: A reverse current protection circuit is set at the output terminal of each DC power supply unit. The reverse current protection circuit includes a unidirectional conducting element connected in series between the positive output terminal of the DC power supply unit and the DC bus, and a reverse current detection element connected in parallel at the output terminal of the DC power supply unit. Each of the DC power supply units collects its own output voltage, output current and internal power device temperature in real time, and compares them with the corresponding preset range; When the output voltage, output current, or internal power device temperature of any DC power supply unit exceeds the corresponding preset range, and the reverse current detection element detects that the reverse current exceeds the preset reverse current threshold, the DC power supply unit is determined to have malfunctioned and a fault flag is generated. In response to the generation of a fault indicator, the DC power supply unit automatically disconnects from the DC bus and exits operation through a unidirectional conduction element, while the remaining DC power supply units on the DC bus automatically increase their output current to compensate for the power deficit. After a DC power supply unit is taken out of service, it sends a fault notification containing the fault event and the time of the fault to other DC power supply units and the operation and maintenance system via the communication bus, and waits for maintenance before being reconnected.

[0027] This invention incorporates a reverse-current protection circuit at the output of each DC power supply unit to prevent current from flowing backward from the DC bus or other DC power supply units into the current DC power supply unit. When any DC power supply unit fails, it automatically disconnects from the DC bus and exits operation. The remaining DC power supply units automatically increase their output current to compensate for the power deficit, allowing the load to continue operating normally. Compared to existing technologies where a single power supply failure paralyzes the entire power supply system, this invention achieves highly reliable operation of the power supply system through the automatic disconnection of the faulty unit and the automatic compensation of the remaining units. The size of the interval and threshold is set to facilitate comparison. The size of the threshold depends on the amount of sample data and the number of bases set by those skilled in the art for each set of sample data; as long as it does not affect the ratio between the parameter and the quantized value.

[0028] The above formulas are all dimensionless calculations. The formulas are derived from software simulations based on a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation. In the embodiments provided in this application, it should be understood that the disclosed system can be implemented in other ways; for example, the system embodiments described above are merely illustrative, for example, the division of modules is merely a logical functional division, and there may be other division methods in actual implementation, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed; another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be indirect coupling or communication connection through some interfaces, devices or modules, and can be electrical, mechanical or other forms; The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A distributed DC power supply system based on industrial logistics robots, characterized in that, include: The distributed power supply module includes multiple DC power supply units distributed along the power supply line. Each DC power supply unit is connected to the DC bus and is used to convert the input power into DC output and supply power to the industrial logistics robot load via the DC bus. The power supply motion planning module is used to generate robot path planning schemes under power supply capacity constraints by using the remaining capacity information of each DC power supply unit as path planning constraints, so that each industrial logistics robot can avoid power-limited areas. The instantaneous power offset module is used to collect the voltage change rate of the local bus in real time, predict the change trend of load power demand based on the voltage change rate, actively adjust the output current before the bus voltage drops, and when any output current has high frequency fluctuations, the adjacent DC power supply unit superimposes the reverse current component into its own output. The health capacity reconfiguration module is used to assess the actual available capacity of the DC power supply unit based on its cumulative operating time, historical output power fluctuation amplitude and temperature rise rate, calculate the remaining capacity ratio based on the actual available capacity and allocate supplementary power. The power feedforward compensation module is used to adjust the output current of each DC power supply unit in advance according to the expected power demand of each industrial logistics robot in the future time window.

2. The distributed DC power supply system based on industrial logistics robots according to claim 1, characterized in that, This is used to generate a robot path planning scheme under power supply capacity constraints, using the remaining capacity information of each DC power supply unit as the path planning constraint. The specific process is as follows: Each DC power supply unit collects its current output current in real time, assesses its health status based on its cumulative running time, historical output power fluctuation range and temperature rise rate, corrects its rated output current with the health status assessment value to obtain the actual usable capacity, and uses the ratio of the difference between the actual usable capacity and the current output current to the actual usable capacity as the proportion of its remaining capacity. The remaining capacity ratio and health status assessment value of each DC power supply unit are obtained and mapped to the location on the power supply line to the field map coordinate system to generate a power supply capacity distribution map. The remaining capacity ratio of the DC power supply unit to which the location point belongs is marked in the power supply capacity distribution map. The current location, target task, and predetermined movement path of each industrial logistics robot are obtained. Multiple path points are sampled at preset distance intervals along the predetermined movement path of each robot. The remaining capacity ratio of each path point is queried according to the power supply capacity distribution map. The expected power demand of each robot along the predetermined movement path is calculated. Path points in each path where the remaining capacity is insufficient to meet the corresponding expected power demand are marked as power supply-limited points. For robots whose predetermined movement path passes through power-limited points, search for alternative paths to avoid power-limited points, and use the alternative paths as the planned paths when they exist. When there is no alternative path, calculate the estimated time when the robot will reach the power-limited point, query the predicted remaining capacity of the power-limited point at the estimated time, and when the predicted remaining capacity is sufficient to meet the expected power demand, adjust the robot's moving speed so that it can reach the power-limited point at the estimated time. When multiple robots pass through the same power supply service area within the same time window and the remaining capacity of the DC power supply unit is insufficient to meet the expected power demand of multiple robots simultaneously, calculate the estimated time when each robot will arrive at the service area, and adjust the moving speed and path of at least one robot so that multiple robots enter the service area of ​​the same DC power supply unit at staggered times.

3. The distributed DC power supply system based on industrial logistics robots according to claim 1, characterized in that, Based on the voltage change rate, the load power demand trend is predicted, and the output current is actively adjusted before the bus voltage drop occurs. The specific process is as follows: Each DC power supply unit continuously collects the voltage value of the local bus at a preset sampling period, calculates the voltage difference between the current sampling period and the previous sampling period, and uses the ratio of the voltage difference to the sampling period as the voltage change rate of the local bus. The voltage change rate is compared with a preset change rate threshold. When the voltage change rate is negative and the absolute value exceeds the preset change rate threshold, it is determined that the load power demand is about to increase. The DC power supply unit increases its own output current in advance before the bus voltage drops below the target value. When the voltage change rate is positive and exceeds the preset change rate threshold, it is determined that the load power demand is about to decrease, and this DC power supply unit reduces its own output current in advance. When multiple DC power supply units simultaneously detect the same rate of voltage change, each DC power supply unit exchanges voltage change rate information through the communication bus and coordinates to adjust the output current according to the preset power allocation ratio, so that the voltage of the DC bus remains stable during the change of load power demand.

4. The distributed DC power supply system based on industrial logistics robots according to claim 1, characterized in that, When a high-frequency fluctuation occurs in any output current, a reverse current component is superimposed on the output of the adjacent DC power supply unit. The specific process is as follows: When the output current of the first DC power supply unit exhibits high-frequency fluctuations exceeding a preset frequency threshold, it sends fluctuation information, including fluctuation frequency, fluctuation amplitude, and fluctuation phase, to the adjacent second DC power supply unit via the communication bus. After receiving the fluctuation information, the second DC power supply unit superimposes a compensation current component into its output current. The frequency of the compensation current component is the same as the fluctuation frequency, the amplitude matches the fluctuation amplitude, and the phase is opposite to the fluctuation phase. This causes the output current fluctuation of the first DC power supply unit and the compensation current component of the second DC power supply unit to cancel each other out after being superimposed on the DC bus, thereby reducing the high-frequency fluctuation amplitude of the bus current.

5. The distributed DC power supply system based on industrial logistics robots according to claim 1, characterized in that, The process is as follows: The actual usable capacity of a DC power supply unit is assessed based on its cumulative operating time, historical output power fluctuation, and temperature rise rate. Each DC power supply unit records its cumulative running time through an internal timer, records the fluctuation range of output power during historical operation through a power detection circuit, and collects the temperature of power devices in real time through a temperature sensor and calculates the temperature rise rate per unit time. Each DC power supply unit assesses its own health status based on cumulative operating time, historical output power fluctuation amplitude, and temperature rise rate. The health status assessment value is inversely correlated with cumulative operating time, historical output power fluctuation amplitude, and temperature rise rate. Each DC power supply unit corrects its rated output current based on its own health status assessment value, and uses the corrected current value as its actual usable capacity. Each DC power supply unit uses the ratio of the difference between its actual available capacity and the current output current to its actual available capacity as its remaining capacity ratio, and sends the remaining capacity ratio and health status assessment value to other DC power supply units through the communication bus.

6. The distributed DC power supply system based on industrial logistics robots according to claim 1, characterized in that, The remaining capacity proportion is calculated and supplementary power is allocated based on the actual available capacity. The specific process is as follows: When a power shortage occurs on the DC bus and needs to be replenished, each DC power supply unit calculates its own power and assigns weights accordingly. Power deficit includes the total power demand of all industrial logistics robots exceeding the sum of the actual available capacity of all DC power supply units, the failure of any DC power supply unit to go out of operation, resulting in a reduction in the total supplied power, and a decrease in the health status assessment value of any DC power supply unit, resulting in a reduction in its actual available capacity and a reduction in the total available supplied power. Each DC power supply unit shares the supplementary power according to its power allocation weight, so that DC power supply units with good health and sufficient remaining capacity bear more supplementary power, while DC power supply units with deteriorating health or insufficient remaining capacity bear less supplementary power. When the health status assessment value of any DC power supply unit is lower than the preset health threshold, the power allocation weight of the DC power supply unit is reduced and a maintenance reminder is generated.

7. The distributed DC power supply system based on industrial logistics robots according to claim 1, characterized in that, The process is as follows: This is used to adjust the output current of each DC power supply unit in advance based on the expected power demand of each industrial logistics robot within a future time window. Obtain the current location, planned movement path, and expected power requirements of each industrial logistics robot. The expected power requirements include the predicted power requirements of each robot at each time point within a future time window. Based on the predetermined movement path of each robot, the service range of the DC power supply unit where each robot is located at each time point is determined. The expected power demand of each robot is assigned according to the service range of the DC power supply unit, and the expected load power of each DC power supply unit at each time point in the future time window is obtained. The expected load power of each DC power supply unit is sent to the corresponding DC power supply unit. Each DC power supply unit adjusts its output current in advance so that the current on the DC bus reaches a level that matches the expected load power before the robot arrives.

8. The distributed DC power supply system based on industrial logistics robots according to claim 1, characterized in that, It also includes an automatic exit mechanism for faulty units and a backflow prevention module, the specific process of which is as follows: A reverse current protection circuit is set at the output terminal of each DC power supply unit. The reverse current protection circuit includes a unidirectional conducting element connected in series between the positive output terminal of the DC power supply unit and the DC bus, and a reverse current detection element connected in parallel at the output terminal of the DC power supply unit. Each of the DC power supply units collects its own output voltage, output current and internal power device temperature in real time, and compares them with the corresponding preset range; When the output voltage, output current, or internal power device temperature of any DC power supply unit exceeds the corresponding preset range, and the reverse current detection element detects that the reverse current exceeds the preset reverse current threshold, the DC power supply unit is determined to have malfunctioned and a fault flag is generated. In response to the generation of a fault indicator, the DC power supply unit automatically disconnects from the DC bus and exits operation through a unidirectional conduction element, while the remaining DC power supply units on the DC bus automatically increase their output current to compensate for the power deficit. After a DC power supply unit is taken out of service, it sends a fault notification containing the fault event and the time of the fault to other DC power supply units and the operation and maintenance system via the communication bus, and waits for maintenance before being reconnected.

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