A power distribution circuit scheduling system for a high-load returning home scenario

Abstract

The present application relates to power supply or distribution circuit device or system, disclose a kind of distribution circuit scheduling system for return high load scene, comprising: follow-up power flow arbitration control module, phase sequence self-adaptive commutation module and zero-crossing capture module, follow-up power flow arbitration control module is used to collect voltage amplitude and determine difference trend parameter;When meeting load progressive overload and voltage amplitude reduction, issue fine adjustment instruction, utilize solid-state mutual switching module to change to highest margin adjacent phase at the moment of current zero-crossing with heavy load branch;When meeting strong impact and voltage is lower than lower limit, activate cross-loop topology closing reconstruction module, the present application utilizes existing network topology structure, dynamically suppresses distribution circuit load imbalance degree, inhibits voltage drop, guarantees local distribution network safe and stable operation.

Description

Technical Field

[0001] This invention belongs to the technical field of power supply or distribution circuit devices or systems, and particularly relates to a power distribution circuit scheduling system for high load scenarios during the return home period. Background Technology

[0002] Currently, low-voltage distribution networks often use transmission lines to form power transmission systems. Load balancing typically relies on outgoing line steady-state voltage monitoring or long-cycle load forecasting. During specific seasonal periods, local residential loads may surge several times over in a short period. The simultaneous connection of large-capacity appliances increases the leakage reactance voltage drop in the windings, resulting in a transient voltage drop on the low-voltage main bus. The differential rate of change of this drop is strongly coupled with the surge in impact load. However, conventional power flow control methods use a large-step sampling mechanism and rely on long-cycle adjustment loops, which cannot capture the transient voltage drop trend within a 10ms window. This causes the issuance of switch change commands to lag behind the heat accumulation process of winding heating, resulting in frequent drops in low-voltage single-phase voltage below the rated lower limit of 198V. This exposes the entire distribution circuit to the risk of insulation aging and winding burnout.

[0003] To address overload heat loss, replacing transformers with larger capacity ones or installing independent energy storage networks would incur high retrofit costs, hindering widespread adoption. If the interconnecting switch is closed between overloaded and idle circuits for capacity balance, a dynamic phase difference exists between the two circuits at the moment of switching, due to their independent network boundaries. At the moment the switch is turned on, this potential difference generates a large parasitic circulating current between the two circuits. This circulating current easily exceeds the current tolerance limit of solid-state switching transistors, leading to thermal breakdown. Furthermore, it can be conducted back to the main bus, inducing secondary voltage fluctuations and creating a limitation where the switch reconfiguration self-healing action and circulating current impact mutually exacerbate each other. While the primary-side hardware network has limitations, the secondary-side control method also suffers from logical deficiencies. For example, Chinese invention patent application CN109586323A discloses a zero-crossing commutation method. The existing technology calculates the zero-crossing times of the original phase sequence current and the new phase sequence voltage by the controller, and controls the operation of the thyristor switch and the relay by combining the preset action delay of the relay. However, this technology implicitly relies on a stable and predictable steady-state power grid environment and a known time delay response of a single fixed load. Under extreme load changes during the return of home, the local power supply circuit generates high-frequency transient nonlinear fluctuations due to the disorderly connection of a large number of high-capacity electrical appliances. The fixed time delay preset and the idealized zero-crossing time axis calculation completely fail when faced with communication delays, loss of main trend sensor data, or switch temperature drift, causing control decision deadlock and frequent jumps and oscillations in the boundary topology. It cannot cope with multi-level collaborative management across loops. The existing control method has a fundamental mismatch when facing the variable boundary conditions of actual non-ideal operating conditions, and it is difficult to ensure the continuous operation and physical safety of multi-loop topology reconfiguration under extreme load impacts.

[0004] Therefore, the technical problem to be solved by this invention is how to use the voltage differential characteristics of the low-voltage outgoing bus to achieve millisecond-level sensing of load impact, and provide zero-crossing phase-controlled locking and nonlinear magnetic saturation inductor damping to eliminate circulating current impact at the moment of cross-loop topology reconfiguration. Summary of the Invention

[0005] This invention aims to solve the problem of how to accurately sense transient load impacts and safely achieve cross-loop topology reconfiguration switching to suppress circulating oscillations.

[0006] In this technical solution, a power distribution circuit dispatching system for high-load scenarios during the return-to-hometown period includes: The power flow arbitration control module is connected to the phase sequence adaptive commutation module and the zero-crossing point capture module respectively. The power flow arbitration control module collects the voltage amplitude in the current sampling window, and subtracts the voltage amplitude at the previous sampling time from the voltage amplitude in the current sampling window and divides it by the fixed differential step size window to determine the current voltage differential trend parameter. If the current voltage differential trend parameter meets the load gradual overload range and the current voltage amplitude decreases to the warning value range, the power flow arbitration control module determines that the local distribution network has entered the load gradual overload stage and sends a phase sequence fine-tuning command to the phase sequence adaptive commutation module. The phase sequence adaptive commutation module includes a solid-state transfer switching module. According to the phase sequence fine-tuning command, at the instant of the current zero-crossing point locked by the zero-crossing point capture module, the phase sequence adaptive commutation module switches the heavy load branch to the adjacent phase with the highest phase voltage margin through the solid-state transfer switching module. If the current voltage differential trend parameter meets the strong impact range of the return load and the current voltage amplitude is lower than the rated voltage lower limit, the follow-up power flow arbitration control module determines that the local distribution network has entered the strong impact stage of the return load, stops the phase sequence balance adjustment and activates the cross-loop topology closing reconstruction module.

[0007] Preferably, when the cross-loop topology closing reconfiguration module is activated, the follow-up power flow arbitration control module extracts the transient fundamental phase difference between the high-load residential power supply circuit and the adjacent idle agricultural and industrial power supply circuit in the local distribution network in real time; when the transient fundamental phase difference is less than or equal to the fixed 2° phase difference threshold and the zero-crossing time of the current fundamental wave is locked by the zero-crossing point capture module, the follow-up power flow arbitration control module sends a closing and diversion command to the corresponding closing control module.

[0008] Preferably, the progressive overload range is -3V / ms to -1V / ms; the warning value range is 198V to 209V; when the current voltage differential trend parameter calculated by the follow-up power flow arbitration control module is in the range of -3V / ms to -1V / ms, and the current voltage amplitude collected is in the range of 198V to 209V, the phase sequence fine-tuning command is triggered.

[0009] Preferably, the strong impact range of the returning load is a value range of less than -3V / ms; the lower limit of the rated voltage is 198V; when the current voltage differential trend parameter calculated by the follow-up power flow arbitration control module is less than -3V / ms, and the current voltage amplitude collected is less than 198V, the phase sequence balance adjustment is stopped and the switch is switched to the cross-loop topology closing reconstruction module.

[0010] Preferably, the solid-state transfer switching module includes a three-phase fast thyristor switching control submodule; the three-phase fast thyristor switching control submodule is configured at the user branch access point on the low-voltage outgoing side of the transformer, and is used to control the opening or blocking of the corresponding user phase sequence circuit.

[0011] Preferably, the zero-crossing point capture module includes a voltage zero-crossing detection submodule and a current zero-crossing detection submodule; the voltage zero-crossing detection submodule is connected to the follow-up power flow arbitration control module for signal transmission and is used to identify the zero-point position of the voltage alternating fundamental wave; the current zero-crossing detection submodule is connected to the phase sequence adaptive commutation module for control signal and is used to lock the zero-crossing time of the current fundamental wave.

[0012] Preferably, the follow-up power flow arbitration control module also includes a delay compensation and correction module; the delay compensation and correction module calculates the inherent response delay based on the sum of the collected control bus transmission delay and the circuit breaker action delay, and adjusts the commutation trigger lead of the solid-state mutual transfer switching module according to the inherent response delay.

[0013] Preferably, the follow-up power flow arbitration control module also includes a dynamic threshold calibration module; the dynamic threshold calibration module reconstructs the upper limit of the bias of the warning value range based on the historical load peak and valley fluctuation data of the previous natural cycle.

[0014] Preferably, the power distribution circuit dispatching system further includes a centralized monitoring module; the centralized monitoring module is wirelessly connected to the follow-up power flow arbitration control module and is used to receive voltage amplitude and historical topology reconstruction action records uploaded by the follow-up power flow arbitration control module.

[0015] Compared with existing technologies, the power distribution circuit dispatching system of the present invention for high load scenarios during the return-to-hometown period has the following advantages: 1. In the dispatching of power distribution circuits in high-load scenarios, the effective value of the total bus voltage collected by the bus status monitoring unit is converted into the voltage differential change rate. When the change rate reaches the threshold, the follow-up power flow arbitration controller controls the three-phase solid-state transfer switch group at the end according to the drop slope. At the moment the current crosses zero, the connection position of the single-phase residential load on the main line is changed. This topology change path will adjust the load to sink to the end of the load branch, so that the phase load of the transformer winding is in a dynamic equilibrium state, reducing the transient imbalance caused by the synchronous start and stop of the single-phase load, reducing the transformer neutral current to attenuate it by more than 80%, limiting the heat accumulation of the winding caused by the sudden increase in load, and realizing the stable operation of the phase voltage on the low-voltage outgoing side.

[0016] 2. When the voltage differential fluctuation rate falls below the set threshold and the effective bus voltage is lower than the rated lower limit, the follow-up power flow arbitration controller controls the dynamic follow-up topology connection matrix connected between different circuits. The phase-controlled trigger locking branch captures the transient voltage fundamental phase difference between the two circuits. When the phase difference boundary is met and the AC current is at the zero-crossing point, the solid-state thyristor switch array is turned on. The magnetic saturation damping characteristics of the nonlinear saturated surge inductor connected in series in the connection bus are used to intercept the parasitic impact circulating current generated at the moment of circuit closing, so as to avoid the circulating current overload and breakdown of the switch components. While maintaining the bus voltage monotonicity judgment standard, the smooth change of the multi-circuit power supply boundary is completed.

[0017] 3. During the short pre-reconfiguration window of the switch, the follow-up power flow arbitration controller controls the transient impedance offset energy storage self-healing network connected in parallel at the node junction. The small-capacity high-frequency pulse supercapacitor bank, together with the bidirectional high-frequency DC to AC converter, injects an equivalent amount of reactive power in reverse according to the negative slope of the current voltage differential change rate, thus supporting the voltage at the end of the line in advance. This impedance pre-offset mechanism physically eliminates the transient flicker of the bus voltage caused by the reactive power release of the inductive load during circuit switching, and controls the voltage fluctuation amplitude of the switching transient to a small level of the rated voltage. This breaks the inherent constraint of the inevitable end voltage drop damage in conventional switches during capacity mutual assistance switching. Attached Figure Description

[0018] Figure 1 This is a structural diagram of a power distribution circuit dispatching system for high-load scenarios during the return-to-hometown period, according to the present invention. Figure 2 This invention provides a state diagram of a power distribution circuit scheduling system for high-load scenarios during the return-to-hometown period. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. The described embodiments are some, but not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0020] A power distribution circuit dispatching system for high-load scenarios during the return-to-hometown period includes: The power flow arbitration control module is connected to the phase sequence adaptive commutation module and the zero-crossing point capture module respectively. The power flow arbitration control module collects the voltage amplitude in the current sampling window, and subtracts the voltage amplitude at the previous sampling time from the voltage amplitude in the current sampling window and divides it by the fixed differential step size window to determine the current voltage differential trend parameter. If the current voltage differential trend parameter meets the load gradual overload range and the current voltage amplitude decreases to the warning value range, the power flow arbitration control module determines that the local distribution network has entered the load gradual overload stage and sends a phase sequence fine-tuning command to the phase sequence adaptive commutation module. The phase sequence adaptive commutation module includes a solid-state transfer switching module. According to the phase sequence fine-tuning command, at the instant of the current zero-crossing point locked by the zero-crossing point capture module, the phase sequence adaptive commutation module switches the heavy load branch to the adjacent phase with the highest phase voltage margin through the solid-state transfer switching module. If the current voltage differential trend parameter meets the strong impact range of the return load and the current voltage amplitude is lower than the rated voltage lower limit, the follow-up power flow arbitration control module determines that the local distribution network has entered the strong impact stage of the return load, stops the phase sequence balance adjustment and activates the cross-loop topology closing reconstruction module.

[0021] Preferably, when the cross-loop topology closing reconfiguration module is activated, the follow-up power flow arbitration control module extracts the transient fundamental phase difference between the high-load residential power supply circuit and the adjacent idle agricultural and industrial power supply circuit in the local distribution network in real time; when the transient fundamental phase difference is less than or equal to the fixed 2° phase difference threshold and the zero-crossing time of the current fundamental wave is locked by the zero-crossing point capture module, the follow-up power flow arbitration control module sends a closing and diversion command to the corresponding closing control module.

[0022] Preferably, the progressive overload range is -3V / ms to -1V / ms; the warning value range is 198V to 209V; when the current voltage differential trend parameter calculated by the follow-up power flow arbitration control module is in the range of -3V / ms to -1V / ms, and the current voltage amplitude collected is in the range of 198V to 209V, the phase sequence fine-tuning command is triggered.

[0023] Preferably, the strong impact range of the returning load is a value range of less than -3V / ms; the lower limit of the rated voltage is 198V; when the current voltage differential trend parameter calculated by the follow-up power flow arbitration control module is less than -3V / ms, and the current voltage amplitude collected is less than 198V, the phase sequence balance adjustment is stopped and the switch is switched to the cross-loop topology closing reconstruction module.

[0024] Preferably, the solid-state transfer switching module includes a three-phase fast thyristor switching control submodule; the three-phase fast thyristor switching control submodule is configured at the user branch access point on the low-voltage outgoing side of the transformer, and is used to control the opening or blocking of the corresponding user phase sequence circuit.

[0025] Preferably, the zero-crossing point capture module includes a voltage zero-crossing detection submodule and a current zero-crossing detection submodule; the voltage zero-crossing detection submodule is connected to the follow-up power flow arbitration control module for signal transmission and is used to identify the zero-point position of the voltage alternating fundamental wave; the current zero-crossing detection submodule is connected to the phase sequence adaptive commutation module for control signal and is used to lock the zero-crossing time of the current fundamental wave.

[0026] Preferably, the follow-up power flow arbitration control module also includes a delay compensation and correction module; the delay compensation and correction module calculates the inherent response delay based on the sum of the collected control bus transmission delay and the circuit breaker action delay, and adjusts the commutation trigger lead of the solid-state mutual transfer switching module according to the inherent response delay.

[0027] Preferably, the follow-up power flow arbitration control module also includes a dynamic threshold calibration module; the dynamic threshold calibration module reconstructs the upper limit of the bias of the warning value range based on the historical load peak and valley fluctuation data of the previous natural cycle.

[0028] Preferably, the power distribution circuit dispatching system further includes a centralized monitoring module; the centralized monitoring module is wirelessly connected to the follow-up power flow arbitration control module and is used to receive voltage amplitude and historical topology reconstruction action records uploaded by the follow-up power flow arbitration control module.

[0029] Example 1: This invention is applied to the low-voltage side of urban and rural power grids to cope with the high load impact caused by concentrated electricity consumption by returning users. The system includes a bus status monitoring unit, a follow-up power flow arbitration control module, and a commutation unit set at the branch access point. The bus status monitoring unit is installed on the main bus of the low-voltage outgoing line of the distribution transformer and collects the transient vector of three-phase voltage at a sampling frequency of 10kHz. The follow-up power flow arbitration control module has built-in discrete processing logic. With a step size of 10ms, it calculates and outputs the voltage differential trend parameter in real time by subtracting the voltage amplitude at the previous sampling moment from the current sampled voltage amplitude and dividing by the differential step size.

[0030] When the follow-up power flow arbitration control module determines that the voltage of phase A has dropped to 205V and the voltage difference trend parameter is -2.1V / ms, the system enters a progressive overload state. At this time, the follow-up power flow arbitration control module issues a phase sequence fine-tuning command, driving the solid-state transfer switch in the commutation unit to operate at the current zero-crossing point, switching the heavy load branch from phase A to phase B. This achieves phase-to-phase load balance of the distribution transformer windings through real-time remapping of the load circuit. During this process, the phase voltage margin is defined as the absolute electromotive force difference between the real-time monitored voltage amplitude of the adjacent phase and the lower limit of the rated voltage. Specifically, the central processing unit synchronously obtains the actual voltage amplitude of the currently non-overloaded adjacent phase B through the bus status monitoring unit. Compared with the actual voltage amplitude of phase C The internal registers perform subtraction operations by subtracting the 198V rated voltage lower limit to construct a deterministic evaluation benchmark. Then, the difference between the two calculation results is compared, and the phase with the largest difference, i.e. the highest absolute electromotive force remaining, is selected as the target adjacent phase. In this embodiment, since the actual voltage margin of phase B is higher than that of phase C, the central processing unit accurately locks phase B and drives the solid-state transfer switch to switch the heavy load branch to phase B, thereby ensuring that the new phase after connection will not drop below the safety boundary due to the sudden increase of heavy load.

[0031] When the follow-up power flow arbitration control module determines that the voltage of phase A drops to 195V and the voltage differential trend parameter deteriorates to -4.2V / ms, the system enters a strong impact state of returning load. The follow-up power flow arbitration control module stops phase sequence adjustment and triggers cross-loop topology closing to reconstruct the control flow. The follow-up power flow arbitration controller extracts the fundamental phase difference between the residential power supply circuit and the adjacent idle power supply circuit in real time. Specifically, the real-time extraction process relies on the dual voltage transformer signal conditioning circuit set in parallel at the junction of the residential power supply circuit and the adjacent idle agricultural and industrial power supply circuit. The signal conditioning circuit acquires the AC voltage waveform of the two circuits in real time through the high-speed voltage transformer and converts the acquired sine wave into a square wave signal of the same amplitude through the zero-crossing comparator. The two square wave signals are synchronously input into the input capture unit of the central processing unit. The central processing unit calculates the time difference between the positive zero-crossing times of the two square waves. And combined with the real-time grid fundamental frequency monitored by the current system phase-locked loop. According to the phase transformation formula The transient fundamental phase difference is calculated, thereby converting the complex AC power grid transient quantity into a high-precision digital scalar. When the phase difference detection value is less than or equal to 2 degrees and the current fundamental zero-point capture module outputs a high level, the system distributes pulses to the thyristor switch array in the dynamic follow-up topology connection matrix.

[0032] At the instant the thyristor turns on, the series-connected nonlinear saturated inductor utilizes its hysteresis loss characteristics to dampen and cut off the inrush circulating current, preventing current oscillations from breaking down the switch. For the microsecond-level reactive power release transient event generated by the inductive load during commutation, the nonlinear saturated inductor connected in series in the tie bus exhibits a high-impedance nonlinear inductance of no less than 0.15H in the unsaturated state during the initial closing phase. This high impedance physically acts as a transient energy buffer, forcibly lengthening and delaying the originally microsecond-level electromagnetic transient process to 10ms by impeding the current surge. The overall control cycle is at a level of 15ms. This timescale transformation mechanism from the surface to the whole provides sufficient response window for the peripheral power electronic control layer, enabling the central processing unit to accurately capture the voltage differential trend and control the bidirectional high-frequency DC-to-AC converter to inject an equivalent amount of reactive power in reverse within a millisecond-level control step window. This physically completes the cross-scale technical bridging. Idle power supply circuits inject active power into residential power supply circuits through interconnection nodes, and the voltage at the end of the residential circuit rises back to 220V within 20ms. During this physical transformation process, in order to provide deterministic topology support and eliminate jump oscillations at the reconfiguration boundary, a transient impedance-hedged energy storage self-healing network composed of a small-capacity high-frequency pulse supercapacitor bank and a bidirectional high-frequency DC-to-AC converter is connected in parallel across the thyristor switch array in the aforementioned dynamic follow-up topology interconnection matrix. The network, and the physical path where the supercapacitor bank is located constitutes a fast energy storage buffer branch; during the short time window before the reconfiguration, the central processing unit injects reactive power in reverse according to the negative slope of the current voltage differential change rate through the converter to achieve impedance pre-counterweighting; when the central processing unit identifies a serious phase-locked mismatch condition where the phase-locked mismatch degree of the two-end circuits exceeds the preset safety range through the dual voltage transformers, the system starts the non-ideal condition fallback locking logic, forcibly blocks the high-frequency conduction pulse of the thyristor switching component, and changes to the closure of the fast energy storage buffer branch, using the supercapacitor bank as an energy storage medium to provide transient power support and complete the dimensionality reduction reconfiguration in the form of transient disconnection and reclosure, thereby cutting off the cross-grid impact circulation path at the physical layer. After the topology reconfiguration is completed, the system enters a 30s lockout state, shields subsequent switching actions, and maintains the steady state of the power supply zone boundary.

[0033] Example 2: This experiment aims to verify the ability of the power flow arbitration controller to regulate the voltage quality of distribution network nodes and its logic steady-state performance in handling high-frequency load fluctuation scenarios. The test platform consists of a three-phase simulated power supply network, a high-load branch load array, and a real-time acquisition and control system. The system configuration is as follows: voltage sampling frequency 10kHz, control step size 10ms, rated inductance of nonlinear saturated inductor of 15mH, and thyristor switch array turn-on delay of 0.2ms.

[0034] The experimental design included a control group to differentiate the synergistic effects of the invention. The experimental group ran the complete control process proposed in this invention, which included voltage differential trend parameter determination and cross-loop topology reconfiguration. Control group A removed the cross-loop topology reconfiguration function, while control group B set the voltage threshold for triggering cross-loop topology reconfiguration to 185V. During the experiment, a high-load scenario of returning home was simulated using a branch load array, causing the load current of the residential power supply circuit to increase at a rate of 10A / s, resulting in a continuous decay of the bus voltage. Monitoring data showed that when the voltage of the experimental group dropped to 195.2V and the voltage differential trend parameter reached -4.2V / ms, the controller initiated the reconfiguration command. Since the thyristor switching array conducts at the current zero-crossing point and the nonlinear saturated inductor provides a reverse electromotive force damping of 0.15H for voltage mutation, the maximum inrush current peak at the moment of circuit reconfiguration was 12.1A.

[0035] The bus voltage in the test group rose from 195.2V to 220.1V within 20.5ms, and maintained a voltage fluctuation amplitude within ±3.1V during the subsequent 120s of load fluctuations. In contrast, control group A, lacking cross-loop power supply capability, saw its bus voltage eventually stabilize at 182.4V. Control group B, due to its excessively low voltage threshold, experienced excessive heat accumulation in the low-voltage winding of the transformer when reconfiguration was triggered, resulting in the inability to effectively maintain the peak voltage operation in subsequent continuous operation. Furthermore, the failure to precisely trigger at the current zero-crossing point caused… The system exhibited a low-frequency oscillation lasting approximately 82.3 ms. Data results indicate that when the voltage differential trend parameter is between -4.2 V / ms and -3.0 V / ms, and the voltage amplitude is between 195.1 V and 197.9 V, the system enters its optimal operating window, achieving smooth suppression of load surges. This collaborative mechanism ensures current continuity and voltage recovery stability during cross-loop topology reconfiguration. The nonlinear saturated surge inductor utilizes an iron-based nanocrystalline soft magnetic alloy core, with an initial permeability in the unsaturated state not less than [value missing]. The corresponding nonlinear inductance is 0.15 H, used to provide high impedance suppression damping for sudden active circulating current; as the cross-loop current increases, the transient current flowing through the inductor exceeds the preset saturation current threshold. At this point, the magnetic core enters magnetic saturation, and the rated inductance drops to 15. saturation current threshold Determined based on Ampere's circuital law and the saturation magnetic induction of the core material: Among them, the saturation current threshold Corresponding saturation magnetic induction intensity The value is 1.25 T, and the average magnetic circuit length is... The permeability of free space is 0.2 m to 0.3 m. for relative permeability The value ranges from 2000 to 5000, representing the number of turns in the coil winding. The value ranges from 40 to 80. By utilizing the adaptive switching of magnetic reluctance state, the peak value of the cross-loop inrush current is smoothed during the closing transient, and the inductive reactance is reduced during the subsequent steady-state operation, thereby reducing the voltage drop loss on the main bus side.

[0036] Example 3: When the urban and rural three-wire low-voltage distribution network faces a short-term, dense gathering of returning migrant workers, causing the load on the residential power circuit to approach the maximum rated output capacity of the transformer, the active power demand in the power supply circuit will experience a significant step change. This will cause a sharp drop in the current voltage amplitude of the main bus of the low-voltage side of the distribution transformer. When the current voltage amplitude drops to 198V, which is the critical switching point between overload warning and strong impact control, and its voltage change rate drops to the edge of the voltage difference trend parameter of 3.0V per millisecond, due to the high-frequency transient fluctuations of the nonlinear load in the local power supply circuit, the control judgment deadlock of the follow-up power flow arbitration controller and frequent jump oscillations of the boundary topology will occur. This state directly affects the physical safety of the solid-state switch array and makes it difficult for the system to maintain a balance between power supply reliability and voltage fluctuation suppression.

[0037] To eliminate this boundary deadlock, the central processing unit (CPU) inside the power flow arbitration controller receives user-side power consumption characteristic data uploaded by each local intelligent terminal. This power consumption characteristic data is pre-anonymized and masked using a secure hash algorithm on the local intelligent terminal to prevent the traceability of personal privacy data. After obtaining the masked current voltage amplitude, the CPU continuously reads the voltage amplitude from the previous sampling time cached in the dynamic random access memory (DRAM). It then subtracts the previous sampling voltage amplitude from the current voltage amplitude and divides the result by a fixed differential step size window of 10ms to calculate the real-time voltage differential trend parameter. To eliminate sampling noise... To mitigate the interference of scattered noise on boundary determination, the central processing unit maintains a sliding time window containing five consecutive sampling cycles in the cache. The statistical variance of the voltage differential trend parameter within this sliding time window is calculated, and its reciprocal is used as a dynamic filtering weight to smooth the voltage differential trend parameter. The 198V voltage threshold and the 3.0V differential trend threshold per millisecond for overload warning and strong impact control switching are based on a transformer thermal accumulation simulation model pre-stored in electrically erasable programmable read-only memory. This model establishes the load loss thermal... The physical monotonically progressive correspondence between current increment and phase voltage sag slope generates a judgment threshold. In multi-circuit collaborative management scenarios, when the distribution network contains a cluster of multiple distribution transformers, if multiple residential power supply circuits simultaneously trigger reconfiguration commands, the top-level power flow arbitration center constructs a hierarchical priority queue based on the product of the current remaining capacity of each distribution transformer and the circuit voltage sag slope. The active power regulation capacity of adjacent idle industrial power circuits is then allocated to each phase sequence adaptive commutation unit or dynamic follow-up topology connection matrix according to the order of the hierarchical priority queue. This is based on the aging of network components during long-term operation of the distribution network. To mitigate the impact of the current fluctuations, the system introduces a historical load baseline database with a sliding window length of 7 days. This database periodically discards outdated historical data and automatically corrects the transformer base loss constant to maintain the timeliness of the control benchmark. If the main trend sensor used to detect voltage dips experiences data loss due to communication delays, the system activates an alternative data path. It reads data from the current rate of change transformer located on the low-voltage side of the distribution transformer's outgoing branch. Based on the current fundamental rate of change, it calculates the alternative load acceleration index to maintain the continuous operation of the power supply topology reconfiguration decision. The secondary side measurement accuracy of the current rate of change transformer is no less than 0.5%, with a physical sampling frequency of 10 kHz. It is installed inside the low-voltage outgoing cabinet to provide an off-site current differential data stream. The central processing unit reads the induced electromotive force signal according to Faraday's law of electromagnetic induction. A high-pass filtering algorithm is used to filter out the alternating fundamental component and high-frequency stray noise to obtain the transient current rate of change, which is then used to calculate the alternative load acceleration index. : Among them, load acceleration index From conversion coefficient The rate of change of transient current difference within a five-cycle sliding time window Multiplication determines the conversion coefficients. Values ​​range from 100 to 500; when the index exceeds the preset safety fluctuation rate threshold of 5000 A / s 2 At this time, the central processing unit writes a strong switching interrupt control word to the trigger pulse register, skipping the conventional voltage amplitude change rate determination process, and sends a full-on drive signal with an amplitude of 5V and a pulse width of 1ms to the gate of the solid-state thyristor switching array. This drives the switching array to close and shunt within 20ms, ensuring scheduling continuity under packet loss conditions. It should be noted that, in order to achieve closed-loop self-consistency in terms of dimensionality and numerical boundaries, the conversion coefficients in the above calculation formula... It is not a dimensionless, purely numerical scalar; its physical meaning is defined as the inverter equivalent conductance adjustment constant caused by a sudden increase in load within a unit sampling period, and its inherent physical dimension is the reciprocal of time; therefore, the conversion coefficient... The first-order differential rate of change of transient current extracted within a five-cycle sliding time window After multiplication, the resulting load acceleration index Its final synthesized physical dimensions are completely equivalent to In actual operating condition verification, when the first-order rate of change of transient current captured by the current transformer on the secondary side inside the low-voltage outgoing switchgear reaches 10A / s... When the speed is 50A / s and accompanied by packet loss, after multiplying by the corresponding adjustment constant, it can be accurately and self-consistently nested within... Within the safety change rate threshold orbit and triggering an interruption, the logical contradiction of dimensional breakage is eliminated in terms of physical principles.

[0038] Driven by this control command flow, when the current voltage amplitude continues to deteriorate at the 198V boundary point due to a sharp increase in load and meets the strong impact judgment condition, the system cross-loop topology closing reconfiguration control flow is initiated. The follow-up power flow arbitration controller outputs thyristor conduction pulses, driving the high-voltage solid-state thyristor switch array to close at the current fundamental zero point. The active power of the idle industrial power circuit is injected into the residential power supply circuit under heavy load within 20ms, adjusting the phase voltage at the end of the circuit from the undervoltage state to the steady-state voltage level of 220V. At the same time, when the load impact subsides and the phase voltage rises back to the preset release threshold, the follow-up power flow arbitration controller controls the switch array to turn off and exit the cross-loop topology closing reconfiguration state. This adjusts the transient power flow impact under extreme boundary conditions, suppresses voltage flicker caused by drastic load changes, and protects the distribution transformer windings from physical structural damage caused by long-term overload and overheating without changing the physical conductor cross-sectional area of ​​the basic transmission and distribution lines.

[0039] Example 4: When the distribution network dispatching system in the distribution network faces the on-site deployment conditions of low-voltage distribution network areas with different operating load histories and ambient temperature variations, the contact impedance of branch circuits and the aging loss state of the distribution transformer windings exhibit non-uniform physical characteristics. Before the distribution network dispatching system is put into topology dispatching, a three-phase balanced 220V standard excitation reference source is introduced by the on-site commissioning test bench. Under the no-load state of the distribution transformer, the bus status monitoring unit continuously collects 100 cycles of transient voltage vector signals. The central processing unit inside the follow-up power flow arbitration controller calculates the amplitude variance of discrete sampling points and filters out stray noise through a moving average filter to obtain the reference offset. The calculated zero-point offset compensation operator is written into the non-volatile storage register of the follow-up power flow arbitration controller for calibrating the zero-point physical bias of the signal sensing channel.

[0040] After the zero-position physical bias calibration of the signal sensing channel, the on-site debugging test bench adjusts the simulated load current of the power supply circuit to increase in step rate of 5A / s with the high-load branch load array until the actual voltage amplitude of the low-voltage side bus of the distribution transformer drops to the critical point of the rated voltage lower limit of 198V. The follow-up power flow arbitration controller reads the secondary side induced current waveform collected by the current change rate transformer set on the outgoing branch and compares it with the rated winding temperature rise limit parameter of the built-in thermal accumulation simulation model. If the differential slip slope of the monitored low-voltage side bus phase voltage within the 10ms differential step window is consistent with the voltage of 3.0V / ms, the test will be conducted. The differential trend parameter threshold value has a deviation. The central processing unit fine-tunes the rate of change correction factor in the non-volatile memory register to match the trigger time of the topology reconstruction instruction output by the servo power flow arbitration controller with the actual physical voltage drop trajectory. This binds the inherent physical characteristics of the distribution transformer with the action threshold. The servo power flow arbitration control module also includes a time delay compensation correction module, which, relying on a central processing unit platform with a high-speed hardware timer, eliminates the action misalignment caused by control link network delay and switching mechanical inertia. The time delay compensation calculation is based on the rigid body kinematic motion delay compensation theory, by accumulating the control bus transmission delay. With circuit breaker operation delay Determine the inherent response delay of the entire system. : Among them, control bus transmission delay The value ranges from 0.02 ms to 0.08 ms, representing the circuit breaker's operating delay. The value ranges from 2.0 ms to 3.5 ms; the central processing unit (CPU) determines the response time based on its inherent latency. Fine-tune the commutation trigger timing of the solid-state inter-transfer module, when the zero-crossing capture module locks the absolute zero of the fundamental voltage alternation. At that time, earlier than The system continuously sends commutation pulse trigger control words to the three-phase fast thyristor switching control submodule, and uses the trigger lead amount to compensate for the physical hardware action time delay, so that the commutation thyristor action time is precisely matched with the zero-crossing point of the current waveform in the time domain.

[0041] Example 5: When the system faces continuous high temperature and high load impact conditions, the internal zero-crossing capture module of the sub-control power circuit and dynamic servo topology connection matrix will experience temperature drift due to the heat generated by the large current conduction. This will cause a 10μs physical potential bias in the zero-crossing signal capture timing. This state will cause the control triggering time of the high-voltage solid-state thyristor switching array to deviate from the fundamental zero point of the current and generate a transient impact circulating current with an amplitude of 45A. The servo power flow arbitration controller will then send an online self-test command to the zero-crossing capture module to retrieve the transient current waveform at the moment of closing of the high-voltage solid-state thyristor switching array in the previous reconfiguration action, extract the 5ms time-domain phase difference between the actual current starting point and the captured zero-crossing signal, and use it as a feedback input to the adaptive compensation regulator.

[0042] The adaptive compensation regulator compares the current time-domain phase difference with the preset 0ms target value, uses a first-order inertial filter to smooth high-frequency time-domain jitter, calculates the zero-crossing trigger delay compensation operator, and writes this zero-crossing trigger delay compensation operator in-situ into the timing correction control word of the dynamic trigger register. This allows for fine-tuning of the trigger control pulse transmission timing in subsequent power flow reconstruction, keeping the closing point phase error of the high-voltage solid-state thyristor switching array within 0.1°, reducing the closing transient impact circulating current from 45.3A to below 4.8A, and keeping the total harmonic distortion rate at the main bus of the distribution network within the 3% rated specification boundary. The opening of branch power supply circuits... With the temperature rise rate of the switching device within the safe carrying capacity threshold, the adaptive compensation regulator internally constructs a front-feedback-feedforward cascaded processing architecture when implementing dual-current fusion control. Specifically, the adaptive compensation regulator recursively iterates the current time-domain phase difference using a first-order inertial filtering algorithm, dynamically filtering out random high-frequency zero-crossing timing noise caused by communication spurious signals or high-frequency harmonics from the power grid, and outputs a dynamic time delay compensation operator as the feedback control reference. The adaptive compensation regulator also initiates the feedforward channel in parallel, using the first-order linear thermal drift temperature compensation model (described later) to locally calculate the static temperature drift time-domain correction caused by the heating effect of long-period continuous high-current conduction. Finally, the central processing unit combines the feedback control reference with the static feedforward time-domain correction. Linear algebraic superposition is performed on the time domain scale, and the resulting data is fused into a unique timing correction control word, which is then written in-situ into the dynamic trigger register. This achieves coordinated correction of dynamic random noise and monotonic thermal drift. The adaptive compensation regulator relies on a high-precision crystal oscillator timer with a clock frequency of no less than 48 MHz. Based on a first-order linear thermal drift temperature compensation model, it collects the transient temperature change within the zero-crossing capture module and calculates the time domain correction corresponding to a 10 μs physical potential bias. : Among them, the time-domain correction amount Temperature drift time compensation coefficient With the current internal ambient temperature Subtract the room temperature calibration reference temperature The difference is multiplied to determine the temperature drift time compensation coefficient. Values ​​range from 0.2 to 0.5 μs / ℃, representing the current internal ambient temperature. Values ​​range from -20℃ to 85℃, with room temperature as the calibration reference temperature. The value is set to 25℃; the central processing unit will adjust the time domain. The timing correction control word accumulated in the dynamic trigger register is used to fine-tune the transmission timing of the trigger control pulse in the subsequent power flow reconstruction, so that the phase error of the closed point of the high-voltage solid-state thyristor switch array is kept within 0.1°, eliminating the microsecond-level zero-crossing identification bias and ensuring the long-term stable operation of the system control loop.

[0043] The embodiments of this application have been described above with reference to the accompanying drawings. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. This application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit of this application and the scope of protection of this invention, and all of these forms are within the protection scope of this application.

Claims

1. A power distribution circuit dispatching system for high-load scenarios involving returning migrant workers, characterized in that, include: The power flow arbitration control module is connected to the phase sequence adaptive commutation module and the zero-crossing point capture module respectively. The power flow arbitration control module collects the voltage amplitude in the current sampling window, and subtracts the voltage amplitude at the previous sampling moment from the voltage amplitude in the current sampling window and divides it by the fixed differential step size window to determine the current voltage differential trend parameter. If the current voltage differential trend parameter meets the load gradual overload range and the current voltage amplitude decreases to the warning value range, the follow-up power flow arbitration control module determines that the local distribution network has entered the load gradual overload stage and sends a phase sequence fine-tuning command to the phase sequence adaptive commutation module. The phase sequence adaptive commutation module includes a solid-state transfer switching module. According to the phase sequence fine-tuning command, at the instant of the current zero-crossing point locked by the zero-crossing point capture module, the phase sequence adaptive commutation module switches the heavy load branch to the adjacent phase with the highest phase voltage margin through the solid-state transfer switching module. If the current voltage differential trend parameter meets the strong impact range of returning load and the current voltage amplitude is lower than the rated voltage lower limit, the follow-up power flow arbitration control module determines that the local distribution network has entered the strong impact stage of returning load, stops the phase sequence balance adjustment and activates the cross-loop topology closing reconstruction module.

2. The power distribution circuit dispatching system for high-load scenarios during the return-to-hometown period, as described in claim 1, is characterized in that... When the cross-loop topology closing reconfiguration module is activated, the follow-up power flow arbitration control module extracts the transient fundamental phase difference between the high-load residential power supply circuit and the adjacent idle agricultural and industrial power supply circuit in the local distribution network in real time. When the transient fundamental phase difference is less than or equal to the fixed 2° phase difference threshold and the zero-crossing moment of the current fundamental wave is locked by the zero-crossing point capture module, the follow-up power flow arbitration control module sends a closing and diversion command to the corresponding closing control module.

3. A power distribution circuit dispatching system for high-load scenarios during the return-to-hometown period, as described in claim 1, is characterized in that... The progressive overload range is -3V / ms to -1V / ms; the warning value range is 198V to 209V; when the current voltage differential trend parameter calculated by the follow-up power flow arbitration control module is in the range of -3V / ms to -1V / ms, and the current voltage amplitude collected is in the range of 198V to 209V, the phase sequence fine-tuning command is triggered.

4. A power distribution circuit dispatching system for high-load scenarios during the return-to-hometown period, as described in claim 1, is characterized in that... The strong impact range of returning load is a value range of less than -3V / ms; the lower limit of rated voltage is 198V; when the current voltage differential trend parameter calculated by the follow-up power flow arbitration control module is less than -3V / ms, and the current voltage amplitude collected is less than 198V, the phase sequence balance adjustment is stopped and the switch is switched to the cross-loop topology closing reconstruction module.

5. A power distribution circuit dispatching system for high-load scenarios during the return-to-hometown period, as described in claim 1, is characterized in that... The solid-state transfer switching module includes a three-phase fast thyristor switching control submodule; the three-phase fast thyristor switching control submodule is configured at the user branch access point on the low-voltage outgoing side of the transformer, and is used to control the opening or blocking of the corresponding user phase sequence circuit.

6. A power distribution circuit dispatching system for high-load scenarios during the return-to-hometown period, as described in claim 1, is characterized in that... The zero-crossing point capture module includes a voltage zero-crossing detection submodule and a current zero-crossing detection submodule; the voltage zero-crossing detection submodule is connected to the follow-up power flow arbitration control module for signal transmission and is used to identify the zero-point position of the voltage alternating fundamental wave; The current zero-crossing detection submodule is connected to the phase sequence adaptive commutation module control signal to lock the time when the fundamental current crosses zero.

7. A power distribution circuit dispatching system for high-load scenarios during the return-to-hometown period, as described in claim 1, is characterized in that... The follow-up power flow arbitration control module also includes a delay compensation and correction module; the delay compensation and correction module calculates the inherent response delay based on the sum of the collected control bus transmission delay and the circuit breaker action delay, and adjusts the commutation trigger lead of the solid-state mutual transfer switching module according to the inherent response delay.

8. A power distribution circuit dispatching system for high-load scenarios during the return-to-hometown period, as described in claim 1, is characterized in that... The follow-up power flow arbitration control module also includes a dynamic threshold calibration module; the dynamic threshold calibration module reconstructs the upper limit of the bias of the warning value range based on the historical load peak and valley fluctuation data of the previous natural cycle.

9. A power distribution circuit dispatching system for high-load scenarios during the return-to-hometown period, as described in claim 1, is characterized in that... The power distribution circuit dispatching system also includes a centralized monitoring module; the centralized monitoring module is wirelessly connected to the follow-up power flow arbitration control module and is used to receive voltage amplitude values ​​and historical topology reconstruction action records uploaded by the follow-up power flow arbitration control module.

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