A method, system and device for selecting an additional pump set for a pump station considering electrical constraints, and a storage medium

Abstract

The application discloses a pump station pump group selection method, system, device and storage medium considering electrical constraints, and belongs to the technical field of water conservancy engineering automation control. The method aims at the problems that the existing pump group starting strategy ignores frequency bus conflict, transformer overload and operation economy, and proposes an innovative framework of "priority sorting + iterative electrical analysis verification". Specifically, after receiving the machine increasing instruction, the priority is selected according to the combination of the pump group and the frequency converter, the algorithm based on graph theory depth / breadth priority search is used, and multiple electrical verifications such as frequency bus conflict analysis, transformer overload analysis and electricity cost analysis are carried out in turn. If the verification fails, the next priority combination is automatically selected, and the optimal solution is found until the safe and economic solution is found. The application realizes the automation and intelligentization of the selection of the pump group and the frequency converter in the increasing field, avoids the pump starting failure and equipment overload, significantly improves the safety and economy of the pump station, and solves the limitations of manual experience decision.

Description

Technical Field

[0001] This invention belongs to the field of water conservancy engineering and industrial automation control technology, specifically relating to a method, system, equipment and storage medium for selecting additional pump sets in a pumping station considering electrical constraints. Background Technology

[0002] Large pumping stations are key infrastructure in national water network projects, undertaking important tasks such as water resource allocation, flood control, and drainage. These pumping stations are typically equipped with multiple pump units (pump sets), and to save investment, they often share a common frequency converter for smooth pump start-up. Traditionally, pump unit startup relies on manually set fixed priorities.

[0003] However, this simple priority sorting method faces serious challenges in practical operation:

[0004] Variable frequency bus conflict: A shared frequency converter drives different pump sets by switching the variable frequency bus. If the variable frequency bus path required for starting a new pump set is already occupied by another pump set that is operating at variable frequency, a conflict will occur, causing the pump to fail to start.

[0005] Transformer overload: Pump units must be connected to a specific transformer to operate. Starting a new pump unit without considering the transformer's current load may cause transformer overload, damage equipment, and threaten the safety of the entire station.

[0006] Operating economics: Large pumping stations typically use a two-part tariff, where the electricity price includes a capacity charge related to maximum demand. If starting a new pump unit increases the maximum demand at the power supply bus inlet, it will significantly increase operating costs.

[0007] Signal reliability: Automation systems rely on sensor signals. If signal anomalies occur (such as a logical contradiction between the circuit breaker status and the pump group status), decisions based on incorrect information will lead to malfunctions.

[0008] A search revealed existing technologies such as patent CN111140515B, which discloses a method for prioritizing backup pumps in the event of a pump set failure, incorporating a health assessment based on operating time; and patent CN118687699B, which discloses an online overload monitoring method for transformers based on a temperature model and machine learning algorithms. However, none of these technologies address the core issue of how to integrate, parallelize, and rapidly simulate and iteratively optimize dynamic electrical topology, real-time load, and economic constraints at the moment the command to activate additional pump sets is triggered.

[0009] Therefore, existing technologies cannot automatically, safely, and economically select the optimal combination of pump sets and frequency converters in scenarios involving increased pump capacity, which restricts the improvement of the level of intelligent operation of pumping stations. Summary of the Invention

[0010] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method, system, equipment, and storage medium for selecting additional pump sets in pumping stations that considers electrical constraints. This addresses the technical problem of how to automatically and reliably select, within milliseconds, a combination of pump sets and frequency converters that meets flow requirements, avoids all electrical conflicts, prevents equipment overload, and optimizes operating costs in scenarios involving additional pump sets. This is achieved through parallel joint simulation and guided iterative optimization based on dynamic electrical main wiring topology.

[0011] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0012] A method for selecting additional pump sets for a pumping station considering electrical constraints includes the following steps:

[0013] S1: Receive an increase in capacity instruction, the increase in capacity instruction containing target traffic information;

[0014] S2: By monitoring the circuit breaker's open / closed status in real time, the electrical main wiring topology reflecting the connection relationship of the pump station's electrical equipment is dynamically constructed;

[0015] S3: Dynamically calculate the pump set start-up priority based on the deviation between the rated flow and the target flow of the pump set. Sort the pump sets according to the order of deviation from small to large, and select candidate pump sets. The formula for calculating the deviation ΔQ between the rated flow and the target flow is: ΔQ=|Q 额定 -Q 目标 |, where Q 额定 Q is the rated flow rate of the pump set. 目标 For target traffic;

[0016] S4: Based on the preset priority ranking of available frequency converters for the candidate pump group, select a candidate frequency converter. The priority ranking of available frequency converters is determined according to the frequency converter's operating frequency and reliability index.

[0017] S5: Perform equipment status logic verification on the combination of the candidate pump group and the candidate frequency converter. The equipment status logic verification includes:

[0018] S51. Verify whether the operating status of the pump set is consistent with the status of its associated power frequency circuit breaker and variable frequency circuit breaker.

[0019] S52. Verify whether the operating status of the transformer is consistent with the status of its associated incoming and outgoing circuit breakers.

[0020] S53. Verify whether the operating status of the frequency converter is consistent with the status of its associated incoming and outgoing circuit breakers.

[0021] If any of the checks in S51, S52, or S53 fails, the pump selection process will be terminated.

[0022] S6: If the equipment status logic verification passes, then perform electrical analysis verification on the combination of the candidate pump group and the candidate frequency converter. The electrical analysis verification includes performing frequency converter bus conflict analysis, transformer overload analysis and electricity cost analysis in sequence.

[0023] The steps for frequency converter bus conflict analysis are as follows:

[0024] S611. Based on the graph theory model and the electrical main wiring topology state constructed in step S2, electrical equipment is used as nodes and closed circuit breakers are used as edges to form a connected graph model.

[0025] S612. Obtain the first path set A_PSN between all pump groups currently in variable frequency operation and the frequency converters used;

[0026] S613. Obtain the second path PST between the candidate pump group and the candidate frequency converter;

[0027] S614. In the connected graph model, search whether the second path PST shares any node other than the source and sink nodes with any path in the first path set A_PSN.

[0028] S615. If a shared node exists, it is determined that there is a frequency converter bus conflict.

[0029] The transformer overload analysis includes:

[0030] S621. Based on the target operating status of the candidate pump group and the target occupancy status of the candidate frequency converter, determine the target opening and closing status of its associated circuit breaker and update it to the electrical main wiring topology status to form a simulated topology G_S.

[0031] S622. In the simulated topology G_S, based on connectivity analysis, determine all pump groups powered by each transformer in operation.

[0032] S623. Based on the search results of the connectivity path, calculate the total power of all operating pump groups connected to each transformer. The formula for calculating the total power is: P 总 =Σ(P i ×t i ), where P i Let t be the rated power of the i-th pump unit. i Let i be the operating time coefficient of the i-th pump group;

[0033] S624. Determine whether the total power exceeds the rated capacity of the corresponding transformer;

[0034] S625. If the value exceeds the limit, the transformer is deemed overloaded.

[0035] The electricity cost analysis includes:

[0036] S631. In the electrical main wiring topology, determine the power supply side incoming bus that supplies power to transformers in all operating states;

[0037] S632. Calculate the current total load of each power supply side incoming bus;

[0038] S633. Query the database to obtain the historical maximum load L of this bus during the current billing cycle, as recorded by the real-time monitoring system. max ;

[0039] If the current total load is greater than the historical maximum load L max If so, the electricity cost analysis is deemed unsuccessful;

[0040] S7: If the electrical analysis verification passes, the combination of the candidate pump group and the candidate frequency converter is determined as the target starting combination;

[0041] S8: If the electrical analysis verification fails, new candidate pump groups and / or candidate frequency converters are selected in order of priority, and the electrical analysis verification is performed until a target start combination that passes the verification is found or all possible combinations are traversed.

[0042] S9: Output the control command for the target start combination.

[0043] Furthermore, the dynamic calculation of pump group start-up priority in step S3 also includes:

[0044] A health coefficient H is introduced based on the pump set's operating history and maintenance status. The health coefficient H is calculated based on the equipment's physical operating parameters, using the formula: H = α × (1 - number of failures / total number of operations) + β × (1 - maintenance delay time / total operating time), where α and β are weighting coefficients, and α + β = 1. For critical pump sets (such as long-running main pumps), a higher β (maintenance delay weight) is set, such as 0.7; for standby pump sets, a higher α (failure frequency weight) is set, such as 0.6. These weightings are based on technical experience from equipment reliability engineering.

[0045] The health coefficient H is combined with the flow deviation ΔQ to form a comprehensive priority score: Score = w1 × (1 - ΔQ / ΔQ) max )+w2×H, where w1 and w2 are weighting coefficients, ΔQ max This represents the maximum permissible flow rate deviation.

[0046] Furthermore, the device status logic verification in step S5 also includes signal reliability verification:

[0047] When the status signal of a pump set, transformer, or frequency converter is logically inconsistent with the status signals of multiple associated circuit breakers, a redundancy signal verification mechanism is activated. This mechanism uses the most recent n status change records of the equipment and the status of associated equipment to perform logical reasoning in order to repair the inconsistent status signals, where n≥3.

[0048] If the redundancy check still cannot determine the correct status, the device will be marked as unavailable and an alarm message will be generated.

[0049] Furthermore, the path search in the variable frequency bus conflict analysis employs an improved depth-first search algorithm, including:

[0050] Establish a device connection matrix M, where M[i][j]=1 indicates that device i and device j are directly connected, and M[i][j]=0 indicates that they are not directly connected.

[0051] The search is recursively initiated from the source device, and the search path and access markers are recorded.

[0052] When a rendezvous device is found, save the complete path;

[0053] Set the maximum search depth D max When the search depth exceeds D max The path search is terminated when D is selected. max The total number of electrical equipment should be twice the size of the pump station.

[0054] Furthermore, the power statistics in the transformer overload analysis utilize real-time power monitoring data, including:

[0055] The output power P of each transformer is collected in real time by smart meters installed on the output side of the transformer. real ;

[0056] The power P collected in real time real The theoretical power P calculated based on the rated power of the pump set calc Compare, when |P real -P calc | / P calc When the value is greater than δ, the power calibration mechanism is activated, where δ is the allowable error threshold.

[0057] The calibrated power value is used for transformer overload detection.

[0058] Furthermore, the electricity cost analysis also includes maximum demand forecasting and cost optimization:

[0059] A bus load prediction model is established based on historical load data to predict the load change trend for the remainder of the current billing cycle.

[0060] When forecasts indicate that the current total load is close to but does not exceed the historical maximum load Lmax At that time, based on the load rate of the transformer and the starting characteristics of the pump group, the load increment caused by adding the pump group and the corresponding marginal electricity cost increment ΔC are calculated.

[0061] If the marginal electricity cost increment ΔC exceeds the set threshold, the electricity cost analysis is deemed unsuccessful.

[0062] A pump station additional pump set selection system considering electrical constraints includes:

[0063] Command receiving module: used to receive additional machine commands;

[0064] Status acquisition module: used to acquire the current status of all pump sets, all frequency converters and the current topology status of the main electrical wiring in the pumping station in real time;

[0065] Pump selection module: used to dynamically calculate the pump start-up priority based on the deviation between the rated flow and the target flow of the pump, and select candidate pumps;

[0066] Inverter selection module: used to select candidate inverters based on the preset priority of available inverters for candidate pump groups;

[0067] Status verification module: used to perform equipment status logic verification on the combination of candidate pump sets and candidate frequency converters;

[0068] Electrical verification module: used to perform electrical analysis and verification on candidate pump groups and candidate frequency converter combinations that have passed the status verification. The electrical analysis and verification includes frequency converter bus conflict analysis, transformer overload analysis and electricity cost analysis.

[0069] Decision output module: When the electrical analysis verification passes, it determines the combination of candidate pump group and candidate frequency converter as the target start combination; and when the electrical analysis verification fails, it triggers the pump group selection module and / or frequency converter selection module to iterate in priority order until the target start combination that passes the verification is found or all possible combinations are traversed.

[0070] Furthermore, the status acquisition module includes:

[0071] Signal acquisition unit: Acquires real-time status signals of pump station equipment through a distributed sensor network;

[0072] Topology building unit: Dynamically constructs the electrical main wiring topology based on the collected equipment status signals and circuit breaker open / closed status;

[0073] The data verification unit verifies the logical consistency and timeliness of the collected signals and eliminates abnormal signals.

[0074] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the method described above. The electronic device further includes:

[0075] Communication interface: Used to communicate with the pump station monitoring system, receive equipment status signals and send control commands;

[0076] Real-time clock: Used to record billing cycles and operation timestamps;

[0077] Data storage unit: Used to store historical operating data, device parameters, and verification rules.

[0078] A non-transitory computer-readable storage medium having a computer program stored thereon, the computer program implementing the above-described methods when executed by a processor, the storage medium further storing:

[0079] Equipment parameter database: includes pump set rated parameters, transformer capacity parameters, and frequency converter technical parameters;

[0080] Historical operation database: records equipment operation history, fault records, and maintenance information;

[0081] Verification rule base: storage device status logic verification rules and electrical analysis verification rules.

[0082] Compared with the prior art, the beneficial effects of the present invention are:

[0083] 1. Significantly improved decision-making speed and accuracy: This invention shortens the complex electrical safety and economic analysis from minutes to milliseconds through "dynamic topology modeling" and "parallel joint simulation", meeting the requirements of real-time scheduling, and fundamentally eliminating hidden electrical conflicts through accurate path simulation;

[0084] 2. Achieving true preventative safety: This invention deeply integrates the real-time health status of equipment into decision-making factors and uses real-time power instead of rated power in overload analysis, enabling decisions to proactively avoid potentially high-risk equipment and improve the inherent safety level of the system.

[0085] 3. Embedded intelligent economic optimization engine: This invention, by integrating an LSTM load forecasting model, transforms electricity cost control from a passive "not exceeding the historical maximum value" to an active "cost-optimal forecasting decision", realizing proactive and intelligent management of operational economy;

[0086] 4. High robustness and adaptability: The intelligent iterative decision controller of this invention can dynamically adjust the optimization path according to the specific reasons for verification failure, avoiding blind exhaustive search, greatly improving the efficiency of finding feasible solutions or quickly determining no solution under complex constraints, and the system has strong adaptability.

[0087] 5. Excellent scalability: The method and system architecture of this invention are clear, easy to integrate into existing pump station computer monitoring systems, and can adapt to different pump station scales and wiring methods, making it highly valuable for promotion and application. Attached Figure Description

[0088] Figure 1 This is the electrical main wiring topology diagram of the present invention;

[0089] Figure 2 This is a schematic diagram of the overall process of the present invention; Detailed Implementation

[0090] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0091] The current status of all pump sets, all frequency converters, and the current topology status of the main electrical wiring in the pumping station are obtained. The current topology status is constructed by real-time monitoring of the circuit breaker's open / closed status.

[0092] Transformers, frequency converters, and water pump motors are connected by wires and circuit breakers. The wires are connected and at the same potential, which can be abstracted as "points". Transformers, frequency converters, and water pump motors are the objects of electrical analysis and verification, which can also be abstracted as "points". The opening and closing of the circuit breaker determines the connection path of the transformer, frequency converter, and water pump motor, which can be abstracted as "lines". By configuring the opening and closing attributes of the circuit breaker on the "line", the operating status of the circuit breaker can be set.

[0093] The pump set selection is performed using a "priority sorting + electrical analysis and verification" algorithm;

[0094] Set the pump group start-up priority order PS=[P(i), P(j), P(k), ...], and set the frequency converter priority order available for each pump group FS=[F(l), F(m), F(n), ...], where i, j, k represent pump group numbers, and l, m, n represent frequency converter numbers.

[0095] Based on the rated flow and target flow of the pump set, the pumps are reordered in ascending order of deviation to form a new priority order PS=[P(k), P(i), P(j), ...].

[0096] Analyze whether the current electrical status of the entire station is normal and whether the statuses of different devices are consistent, including the following judgments:

[0097] The consistency of the pump set and its circuit breaker status, for example, when the pump set is in power frequency operation, its power frequency circuit breaker should be closed, and its variable frequency circuit breaker should be open;

[0098] The consistency of the transformer and its circuit breaker status; for example, when the transformer is in operation, both its incoming and outgoing circuit breakers should be closed.

[0099] The consistency of the status of the frequency converter and its circuit breakers, for example, when the frequency converter is occupied, both its incoming and outgoing circuit breakers should be closed.

[0100] If all the above electrical conditions are normal, proceed to the next step; otherwise, exit.

[0101] 1) Select the pump group represented by the first element PS[0] of the pump group start priority sorting PS, and determine whether the pump group PS[0] is available. The pump group start needs to determine the following conditions:

[0102] When the pump unit is put into operation, the information is manually set to determine whether the pump unit is in automatic operation mode.

[0103] The pump unit is fault-free, and the signal is taken from the monitoring and acquisition signal to determine the fault-free status of the pump unit.

[0104] The pump unit is in a stopped state, and the signal is taken from the monitoring and acquisition signal to determine that the pump unit is currently in a stopped state.

[0105] If all pump start-up conditions are met, the pump set is available and proceed to the next step; otherwise, delete the first element of the PS sequence and select again.

[0106] Select the first element FS[0] of the inverter startup priority sorting FS to represent the inverter. Determine whether inverter FS[0] is available. The availability of the inverter needs to be determined based on the following conditions:

[0107] Inverter available: The signal is taken from the monitoring and acquisition signal to determine the current availability status of the inverter;

[0108] Inverter activation: Information is manually set to determine the inverter's activation status;

[0109] If all the conditions for the frequency converter to be available are met, the frequency converter is available and proceed to the next step; otherwise, delete the first element of the FS sequence and select the next one according to priority.

[0110] The variable frequency bus conflict analysis specifically includes the following steps:

[0111] There are four effective transition relationships between the current operating state and the target operating state of the pump set, as shown in Table 1. During the transition from the current state to the target state, the pump set in the current state of "variable frequency operation" occupies the frequency converter and variable frequency bus, while the pump set in the target state of "power frequency operation" or "variable frequency operation" needs to use the frequency converter and variable frequency bus.

[0112] Table 1. Comparison of Inverter Usage between Current and Target Operating States of Pump Units

[0113]

[0114] Variable frequency bus conflict essentially involves analyzing whether the path PSN between the pump motor and the frequency converter in the current "variable frequency operation" state overlaps with the path PST between the pump motor and the starting frequency converter in the target state of "power frequency operation" or "variable frequency operation". If the points on the two paths overlap, it indicates that the bus or frequency converter is being used repeatedly, and the current state conflicts with the set target state, as detailed below:

[0115] 1. Path PSN Calculation

[0116] For the pump group P(i) currently operating under variable frequency drive (VFD) conditions, its VFD is F(l). Using P(i) as the source and F(l) as the sink, a path from the source to the sink is found in the topology analysis graph using either Depth-First Search (DFS) or Breadth-First Search (BFS). The "points" in this path are stored as vectors in PSN(i). DFS and BFS algorithms are well-established and will not be elaborated further. PSN(i) contains the path information between the motor and the VFD of the pump group P(i) currently in "variable frequency drive operation," and the "points" in this path include the pump group number, wire number, and VFD number.

[0117] There may be multiple pump sets currently operating at variable frequency. For all pump sets operating at variable frequency, a set is obtained that stores the current path PSN:

[0118] A_PSN=[PSN(i), PSN(j), PSN(k), ...], where i, j, and k are the pump group numbers currently in "variable frequency operation".

[0119] 2. Path PST Calculation

[0120] For the pump set P(n) to be started, the frequency converter F(m) is used for starting. With the source point P(n) as the source point and F(m) as the sink point, the path is calculated using the DFS or BFS algorithm, and the "points" in the path are stored in PST(n) in vector form.

[0121] 3. Overlap analysis of PST and PSN

[0122] For each path PSN in A_PSN, the pump group number, bus number, and inverter number are stored. Similarly, PST(n) stores the pump group number, bus number, and inverter number. Determine if each element of PST(n) is contained within a PSN. If so, it indicates a route conflict. The pseudocode for this process is as follows:

[0123] Conflict_flag=0

[0124] for PSN in A_PSN:

[0125] for node in PST(n):

[0126] if PSN has node:

[0127] conflict_flag=1

[0128] Transformer overload analysis includes the following steps:

[0129] Transformer load analysis essentially involves analyzing whether a connection exists between the motor of pump unit P(i) and transformer T(j) in the "operating" state, meaning whether the pump unit motor and transformer can be connected via a closed circuit breaker. If a connection exists between the pump unit motor and transformer, it indicates that pump unit P(i) is connected to T(j). Therefore, the transformer load analysis calculation process is as follows:

[0130] 1. The pump unit P(n) to be started uses a frequency converter F(m). After analysis, the frequency converter bus does not conflict. P(n) and F(m) are set to the running state.

[0131] 2. Reverse the settings of the incoming and outgoing circuit breakers of P(n) and F(m). If P(n) is in variable frequency operation, its variable frequency side circuit breaker is closed, and its power frequency side circuit breaker is open; if P(n) is in power frequency operation, its variable frequency side circuit breaker is open, and its power frequency side circuit breaker is closed. If the pump set driven by F(m) is in variable frequency operation, the frequency converter is always occupied, and its incoming and outgoing circuit breakers are closed; if the pump set driven by F(m) is in power frequency operation, the frequency converter has been released, and its incoming and outgoing circuit breakers are open.

[0132] 3. Delete the "line" of the circuit breaker with the attribute of "division" on the topology graph G to form a new topology graph G_S.

[0133] 4. All transformers in operation form a set A_T, and all pump sets in operation (including "power frequency operation" and "variable frequency operation") form a set A_P.

[0134] 5. In G_S, cross-pollinate each element in A_T and each element in A_P to see if there is a path. If the path exists, attach a pump set to T(j).

[0135] 6. Calculate the number of pump sets under each transformer. If the total power of the pump sets is less than the transformer capacity, then the transformer will not be overloaded.

[0136] Electricity cost analysis includes the following steps:

[0137] The lowest electricity cost essentially depends on whether the capacity load on the power source side incoming bus increases during the metering period. If the power source side incoming bus L(i) and transformer T(j) are connected, then the load in T(j) is connected to L(i). Therefore, the electricity cost analysis and calculation process is as follows:

[0138] 1. All incoming busbars on the power supply side form a set A_L, and all operating transformers form a set A_T.

[0139] 2. Based on the transformer load analysis, calculate the load of L(i) iteratively.

[0140] 3. Compare the load of L(i) with the maximum load Lmax(i) of the current billing cycle. If L(i) > Lmax(i), the test fails. Lmax(i) requires manual maintenance.

[0141] Finally, the target operating mode of the pump set is set, and control commands are issued:

[0142] If the selected pump set is a variable frequency pump, a variable frequency operation command is issued; if the selected pump set is a fixed frequency pump, a fixed frequency operation command is issued to ensure that the pump's operating mode matches its design and function.

[0143] Comparative Example: Traditional Manual Decision-Making

[0144] Engineer's analysis: The engineer checked the rated flow of each pump group and found that the flow requirement (total 850 m³ / h) could be met by starting the three units P6 (300 m³ / h), P7 (280 m³ / h), and P8 (270 m³ / h) at the same time. All three units were in standby mode, so P6, P7, and P8 were initially selected.

[0145] Electrical Check: The engineer manually checked the electrical wiring diagram and found that both P6 and P8 need to be connected to transformer T3. Based on experience, it was estimated that P6 (220kW) + P8 (200kW) + the existing load was close to the capacity limit of T3 (800kVA), but it was considered "should be fine". At the same time, an idle frequency converter F1 was allocated to P7.

[0146] Conflict overlooked: Due to the complexity of the current topology, the engineer failed to identify that starting P2 (variable frequency operation) had occupied part of the variable frequency bus associated with the starting paths of P6 and P8.

[0147] Decision result: The engineer issued an instruction to start P6, P7, and P8 simultaneously.

[0148] Actual running results:

[0149] Variable frequency bus conflict: The start command of P6 conflicts with the running P2 path, causing the closing to fail, issuing an alarm, and the start process to be aborted.

[0150] Transformer short-term overload: P8 started successfully, but when combined with the existing loads such as P2, the load on transformer T3 instantly reached 105% of its rated capacity, lasting for about 2 minutes, triggering an overload warning. The system was forced to disconnect some non-critical loads, which posed an extremely high risk.

[0151] Decision failure: Only P7 started successfully, with an actual increase in flow of 280 m³ / h, which did not meet the target. The entire decision-making and troubleshooting process took approximately 8 minutes.

[0152] Example 1

[0153] like Figure 1-2 As shown, a method for selecting additional pump sets for a pumping station considering electrical constraints includes the following steps:

[0154] S1: Receives a request to add more machines, which includes the target traffic volume Q. target =500 m³ / h;

[0155] S2: Obtain the current status of all pump sets, all frequency converters, and the current topology status of the main electrical wiring in the pumping station;

[0156] The current pumping station is equipped with 5 pump sets (P1-P5), 3 frequency converters (F1-F3), and 2 transformers (T1-T2);

[0157] The device status signals are collected in real time through a distributed sensor network, with a sampling frequency of 1Hz.

[0158] Based on the collected signals, an electrical main wiring topology diagram is constructed, such as... Figure 1 As shown.

[0159] S3: Dynamically calculate the pump set start-up priority based on the deviation between the rated flow and the target flow of the pump set, and select candidate pump sets;

[0160] Rated flow rates of each pump group: P1: 200 m³ / h, P2: 180 m³ / h, P3: 220 m³ / h, P4: 190 m³ / h, P5: 210 m³ / h;

[0161] Calculate the flow deviation ΔQ:

[0162] ΔQ1=|200-500|=300, ΔQ2=|180-500|=320, ΔQ3=|220-500|=280, ΔQ4=|190-500|=310, ΔQ5=|210-500|=290;

[0163] Preliminary sort: P3(280), P5(290), P1(300), P4(310), P2(320);

[0164] Introducing a health coefficient H, the health status of each pump group:

[0165] H1=0.92, H2=0.85, H3=0.96, H4=0.88, H5=0.94;

[0166] Calculate the overall priority score (assuming w1=0.6, w2=0.4):

[0167] Score1=0.6×(1-300 / 500)+0.4×0.92=0.608;

[0168] Score3=0.6×(1-280 / 500)+0.4×0.96=0.648;

[0169] Score5=0.6×(1-290 / 500)+0.4×0.94=0.628;

[0170] Final priority ranking: P3 (0.648), P5 (0.628), P1 (0.608), P4 (0.592), P2 (0.576);

[0171] Select candidate pump group P3.

[0172] S4: Select a candidate frequency converter based on the priority ranking of available frequency converters preset for candidate pump group P3;

[0173] Available inverter priority for P3: FS=[F2, F1, F3];

[0174] Select candidate frequency converter F2.

[0175] S5: Perform device status logic verification;

[0176] Verify whether the operating status of pump unit P3 is consistent with the status of its associated power frequency circuit breaker and variable frequency circuit breaker.

[0177] Verify whether the operating status of transformers T1 and T2 is consistent with the status of their associated incoming and outgoing circuit breakers;

[0178] Verify whether the operating status of frequency converter F2 is consistent with the status of its associated incoming and outgoing circuit breakers.

[0179] All state logics were found to be consistent; verification passed.

[0180] S6: Perform electrical analysis and verification on the combination of candidate pump group P3 and candidate frequency converter F2;

[0181] Variable frequency bus conflict analysis:

[0182] Construct an electrical main wiring topology diagram, abstracting equipment as vertices and circuit breakers as edges;

[0183] The pump set currently operating under variable frequency drive is P1 (using F1). Calculate its path PSN1.

[0184] Calculate the path PST of candidate combination P3-F2;

[0185] Using pump unit P3 as the source point and frequency converter F2 as the sink point, the DFS algorithm is used to search in the connected graph model. The maximum search depth Dmax=20 is set to prevent infinite recursion in complex topologies. This is a technical setting based on the scale of the pump station.

[0186] Comparing the vertex sets of PST and PSN1, we find that there is no overlap or conflict.

[0187] Transformer overload analysis:

[0188] The simulation sets P3 and F2 to the running state, updates the associated circuit breaker states, and forms the simulation topology G_S;

[0189] Traverse the connection path between the transformer and the pump group in G_S;

[0190] The following pump sets are connected to transformer T1: P1 (200kW), P3 (220kW), with a total power of 420kW.

[0191] Transformer T1 has a rated capacity of 500kW, and 420kW < 500kW, so it is not overloaded.

[0192] The real-time output power of T1, collected by the smart meter, is 418kW, with a deviation of less than 1% from the calculated value, indicating that the calibration has passed.

[0193] Electricity cost analysis:

[0194] The power supply side incoming bus L1 is determined to supply power to transformers T1 and T2;

[0195] Calculate the current total load of L1: 850kW;

[0196] Query the database to obtain the historical maximum load L1 for the current billing cycle. max =900kW;

[0197] 850kW < 900kW, electricity cost analysis passed;

[0198] Based on historical data, the load for the remaining time of this cycle is predicted to be no more than 900kW.

[0199] S7: All electrical analysis and verifications have passed; the P3-F2 combination has been determined as the target startup combination.

[0200] S8: Output the control command for starting the target combination.

[0201] Example 2

[0202] This embodiment aims to demonstrate the significant advantages of the present invention over traditional methods in large and complex pumping stations facing multiple electrical constraints.

[0203] Pump station scale: equipped with 10 water pump units (P1-P10), 5 frequency converters (F1-F5), and 3 transformers (T1, T2, T3), of which T1 has a rated capacity of 1000kVA, T2 has a rated capacity of 1250kVA, and T3 has a rated capacity of 800kVA.

[0204] Initial state: Simulating a typical operating condition, P1, P3, and P4 are in power frequency operation (connected to T1); P2 is in the process of starting up a frequency converter driven by frequency converter F2; P5-P10 are in a stopped state. Frequency converters F1, F3, F4, and F5 are idle.

[0205] Target instruction: Received instruction to increase capacity, target flow rate is +850m³ / h.

[0206] Dynamic Priority Ranking: After receiving the target flow rate of 850 m³ / h, the system first calculates the rated flow rate deviation of all stopped pump groups (P5-P10) and then calculates their overall priority score based on their health coefficient H (P6 has a lower H value of 0.76 due to recent minor fault records). Ultimately, P7, P9, and P10 are selected as the candidate pump group combination (flow rates of 280, 300, and 300 m³ / h respectively, totaling 880 m³ / h, with the highest score).

[0207] Equipment status logic verification: The system verifies the consistency of the status logic of P7, P9, P10 and their associated circuit breakers, and all passes.

[0208] Electrical analysis and verification:

[0209] Variable frequency bus conflict analysis: Based on the real-time topology, the system uses an improved DFS algorithm (with Dmax=40) to quickly calculate the paths P7-F1, P9-F3, and P10-F4. The results confirm that all paths do not share nodes with the currently running P2-F2 path and there are no conflicts.

[0210] Transformer overload analysis: The system simulates the start-up of P7, P9, and P10, and uses real-time power data from smart meters for calibration. Calculations show that the simulated loads of T1, T2, and T3 are 92%, 88%, and 79%, respectively, all within their rated capacity, indicating no risk of overload.

[0211] Electricity cost analysis: The system queries the database to find the historical maximum load L of the current incoming bus L1. max The load is 4500kW. The total load after simulated startup is 4300kW, and the maximum demand prediction model shows that the load will not exceed L for the remainder of this billing cycle. max The marginal electricity cost increment ΔC is almost zero, thus the economic analysis is successful.

[0212] Decision result: The system completed all analyses within 22 seconds, determined the target startup combination to be P7-F1, P9-F3, and P10-F4, and issued control commands. The pump sets started smoothly in sequence, with an actual increase in flow rate of 880 m³ / h, perfectly meeting the requirements, and no alarms were triggered throughout the entire process.

[0213] For statistical comparison, the two methods were tested with 100 consecutive random increment commands in a simulation environment of the same scale. The results are shown in Table 2 below:

[0214] Table 2. Comparison of overall performance of Example 2 and traditional method in 100 tests

[0215]

[0216] Table 2 shows the significant value of this invention in complex application scenarios:

[0217] The unity of efficiency and reliability: This invention reduces decision-making time from several minutes to less than half a minute through automated and intelligent multi-level verification, while improving the success rate of decision-making to a near-perfect level, thus solving the problems of low efficiency and poor reliability of manual decision-making.

[0218] Active safety defense: By analyzing the frequency converter bus conflict and transformer overload, this invention transforms the risk of electrical conflict and overload from "post-event alarm" to "pre-event prevention", thus achieving inherent safety.

[0219] Economic efficiency is embedded in decision-making: The electricity cost analysis module transforms business rules into technical constraints, avoiding unnecessary cost increases at the source of decision-making, a capability that traditional methods completely lack.

[0220] Synergistic Effect of Technical Features: This embodiment highlights that the health coefficient, improved DFS algorithm, real-time power calibration, and maximum demand prediction do not operate in isolation. For example, the health coefficient excludes P6, indirectly avoiding the cascading effects of potential equipment failures on transformer load and operating economy. This synergistic effect of "1+1>2" resulting from the deep interaction between technical features is the key manifestation of the inventiveness of this invention and cannot be replicated by traditional manual experience.

[0221] Explanation of relevant technical terms:

[0222] Additional pumps: To meet the increased flow demand, large pump stations need to operate additional pump units.

[0223] Variable frequency bus conflict: To achieve a smooth start-up of pump units, large pumping stations are equipped with variable frequency drives (VFDs) during construction. To save investment, the number of VFDs is generally less than the number of pump units. Since the pump units are driven by VFDs, if they operate in VFD mode after startup, they will continuously occupy the VFDs and VFD bus, thus affecting the startup of other pump units.

[0224] Transformer overload: The pumping station is equipped with multiple transformers. By adjusting the busbar switch, the pump unit can operate under one of the transformers. In automatic start-stop mode, it is necessary to consider whether the transformer will be overloaded after the pump unit is connected to the transformer, to prevent the transformer from exceeding its rated power during operation and causing damage to the transformer equipment.

[0225] Electrical analysis and verification: Describe the relationship between the current operating status of equipment such as water pump motors, frequency converters, transformers, and circuit breakers and the status after the pump set is started.

[0226] Health coefficient: A comprehensive indicator characterizing the operating status of pump set equipment, calculated based on factors such as equipment failure history, maintenance records, and operating time.

[0227] Maximum demand: In the two electricity pricing systems, it refers to the maximum value of the average active load of a user every 15 minutes within a billing cycle.

[0228] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for selecting additional pump sets for a pumping station considering electrical constraints, characterized in that, Includes the following steps: S1: Receive an increase in capacity instruction, the increase in capacity instruction containing target traffic information; S2: By monitoring the circuit breaker's open / closed status in real time, the electrical main wiring topology reflecting the connection relationship of the pump station's electrical equipment is dynamically constructed; S3: Dynamically calculate the pump set start-up priority based on the deviation between the rated flow and the target flow of the pump set. Sort the pump sets according to the order of deviation from small to large, and select candidate pump sets. The formula for calculating the deviation ΔQ between the rated flow and the target flow is: ΔQ=|Q 额定 -Q 目标 |, where Q 额定 Q is the rated flow rate of the pump set. 目标 For target traffic; S4: Based on the preset priority ranking of available frequency converters for the candidate pump group, select a candidate frequency converter. The priority ranking of available frequency converters is determined according to the frequency converter's operating frequency and reliability index. S5: Perform equipment status logic verification on the combination of the candidate pump group and the candidate frequency converter; S6: If the equipment status logic verification passes, then perform electrical analysis verification on the combination of the candidate pump group and the candidate frequency converter. The electrical analysis verification includes performing frequency converter bus conflict analysis, transformer overload analysis and electricity cost analysis in sequence. S7: If the electrical analysis verification passes, the combination of the candidate pump group and the candidate frequency converter is determined as the target starting combination; S8: If the electrical analysis verification fails, new candidate pump groups and / or candidate frequency converters are selected in order of priority, and electrical analysis verification is performed until a target start combination that passes the verification is found or all possible combinations are traversed. S9: Output the control command for the target start combination.

2. The method according to claim 1, characterized in that, The dynamic calculation of pump group start-up priority in step S3 also includes: A health coefficient H is introduced based on the pump set's operating history and maintenance status. The health coefficient H is calculated based on the equipment's physical operating parameters, and the calculation formula is: H = α × (1 - number of failures / total number of operations) + β × (1 - maintenance delay time / total operating time), where α and β are weighting coefficients, and α + β = 1. The health coefficient H is combined with the flow deviation ΔQ to form a comprehensive priority score: Score = w1 × (1 - ΔQ / ΔQ) max )+w2×H, where w1 and w2 are weighting coefficients, ΔQ max This represents the maximum permissible flow rate deviation.

3. The method according to claim 1, characterized in that, The device status logic verification in step S5 includes: S51. Verify whether the operating status of the pump set is consistent with the status of its associated power frequency circuit breaker and variable frequency circuit breaker. S52. Verify whether the operating status of the transformer is consistent with the status of its associated incoming and outgoing circuit breakers. S53. Verify whether the operating status of the frequency converter is consistent with the status of its associated incoming and outgoing circuit breakers. If any of the checks in S51, S52, or S53 fails, the pump selection process will be terminated. It also includes signal reliability verification: When the status signal of a pump set, transformer, or frequency converter is logically inconsistent with the status signals of multiple associated circuit breakers, a redundancy signal verification mechanism is activated. This mechanism uses the most recent n status change records of the equipment and the status of associated equipment to perform logical reasoning in order to repair the inconsistent status signals, where n≥3. If the redundancy check still cannot determine the correct status, the device will be marked as unavailable and an alarm message will be generated.

4. The method according to claim 1, characterized in that, The variable frequency bus conflict analysis steps in step S6 are as follows: S611. Based on the graph theory model and the electrical main wiring topology state constructed in step S2, electrical equipment is used as nodes and closed circuit breakers are used as edges to form a connected graph model. S612. Obtain the first path set A_PSN between all pump groups currently in variable frequency operation and the frequency converters used; S613. Obtain the second path PST between the candidate pump group and the candidate frequency converter; S614. In the connected graph model, search whether the second path PST shares any node other than the source and sink nodes with any path in the first path set A_PSN. S615. If a shared node exists, it is determined that there is a frequency converter bus conflict. The transformer overload analysis includes the following steps: S621. Based on the target operating status of the candidate pump group and the target occupancy status of the candidate frequency converter, determine the target opening and closing status of its associated circuit breaker and update it to the electrical main wiring topology status to form a simulated topology G_S. S622. In the simulated topology G_S, based on connectivity analysis, determine all pump groups powered by each transformer in operation. S623. Based on the search results of the connectivity path, calculate the total power of all operating pump groups connected to each transformer. The formula for calculating the total power is: P 总 =Σ(P i ×t i ), where P i Let t be the rated power of the i-th pump unit. i Let i be the operating time coefficient of the i-th pump group; S624. Determine whether the total power exceeds the rated capacity of the corresponding transformer; S625. If the value exceeds the limit, the transformer is deemed overloaded. The electricity cost analysis includes the following steps: S631. In the electrical main wiring topology, determine the power supply side incoming bus that supplies power to transformers in all operating states; S632. Calculate the current total load of each power supply side incoming bus; S633. Query the database to obtain the historical maximum load L of this bus during the current billing cycle, as recorded by the real-time monitoring system. max ; If the current total load is greater than the historical maximum load L max If so, the electricity cost analysis is deemed unsuccessful.

5. The method according to claim 4, characterized in that, The path search in the variable frequency bus conflict analysis employs an improved depth-first search algorithm, including: Establish a device connection matrix M, where M[i][j]=1 indicates that device i and device j are directly connected, and M[i][j]=0 indicates that they are not directly connected. The search is recursively initiated from the source device, and the search path and access markers are recorded. When a rendezvous device is found, save the complete path; Set the maximum search depth D max When the search depth exceeds D max The path search is terminated when D is selected. max The total number of electrical equipment should be twice the size of the pump station.

6. The method according to claim 4, characterized in that, The power statistics in the transformer overload analysis use real-time power monitoring data, including: The output power P of each transformer is collected in real time by smart meters installed on the output side of the transformer. real ; The power P collected in real time real The theoretical power P calculated based on the rated power of the pump set calc Compare, when |P real -P calc | / P calc When the value is greater than δ, the power calibration mechanism is activated, where δ is the allowable error threshold. The calibrated power value is used for transformer overload detection.

7. The method according to claim 4, characterized in that, The electricity cost analysis also includes maximum demand forecasting and cost optimization: A bus load prediction model is established based on historical load data to predict the load change trend for the remainder of the current billing cycle. When the forecast shows that the current total load is close to but does not exceed the historical maximum load Lmax, the load increment caused by adding pumps and the corresponding marginal electricity cost increment ΔC are calculated by combining the load rate of the transformer and the starting characteristics of the pump group. If the marginal electricity cost increment ΔC exceeds the set threshold, the electricity cost analysis is deemed unsuccessful.

8. A pump station additional pump set selection system considering electrical constraints for implementing the method as described in any one of claims 1 to 7, characterized in that, include: Command receiving module: used to receive additional machine commands; Status acquisition module: used to acquire the current status of all pump sets, all frequency converters and the current topology status of the main electrical wiring in the pumping station in real time; Pump selection module: used to dynamically calculate the pump start-up priority based on the deviation between the rated flow and the target flow of the pump, and select candidate pumps; Inverter selection module: used to select candidate inverters based on the preset priority of available inverters for candidate pump groups; Status verification module: used to perform equipment status logic verification on the combination of candidate pump sets and candidate frequency converters; Electrical verification module: used to perform electrical analysis and verification on candidate pump groups and candidate frequency converter combinations that have passed the status verification. The electrical analysis and verification includes frequency converter bus conflict analysis, transformer overload analysis and electricity cost analysis. Decision output module: When the electrical analysis verification passes, it determines the combination of candidate pump group and candidate frequency converter as the target start combination; and when the electrical analysis verification fails, it triggers the pump group selection module and / or frequency converter selection module to iterate in priority order until the target start combination that passes the verification is found or all possible combinations are traversed.

9. The system according to claim 8, characterized in that, The status acquisition module includes: Signal acquisition unit: Acquires real-time status signals of pump station equipment through a distributed sensor network; Topology building unit: Dynamically constructs the electrical main wiring topology based on the collected equipment status signals and circuit breaker open / closed status; The data verification unit verifies the logical consistency and timeliness of the collected signals and eliminates abnormal signals.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method as described in any one of claims 1 to 7, and the storage medium further stores: Equipment parameter database: includes pump set rated parameters, transformer capacity parameters, and frequency converter technical parameters; Historical operation database: records equipment operation history, fault records, and maintenance information; Verification rule base: storage device status logic verification rules and electrical analysis verification rules.

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