An energy-saving scheduling method for parallel water supply pump groups considering transitional energy efficiency

Abstract

The present invention relates to the field of energy and energy-saving technology, and specifically to an energy-saving scheduling method for a parallel water supply pump group considering transition energy efficiency, comprising the following steps: step one, accessing historical operation data of a water supply pump group; step two, establishing an energy efficiency performance model of a water supply pump group considering the transition energy efficiency of a water supply pump; step three, establishing an energy-saving scheduling model for a water supply pump group, completing the scheduling of pump group operation instructions and the calculation of required energy consumption; the present invention establishes energy efficiency performance models of water supply pumps considering the transition energy efficiency of water supply pumps for industrial frequency pumps and variable frequency pumps, respectively, and proposes a method for calculating the transition energy efficiency of water supply pumps with total transition time consumption, total transition energy consumption and total transition water supply as objects, and avoids complex theoretical calculations in the transition process by integrating time curves and establishing a regression model based on an artificial intelligence method, so as to realize the quantification of the required time, required energy consumption and water supply output of each water supply pump in the transition operation state.

Description

Technical Field

[0001] The invention relates to the field of energy and energy-saving technology, and in particular to an energy-saving scheduling method for a parallel water supply pump group taking transition energy efficiency into consideration. Background Art

[0002] As a power equipment widely used in the field of industrial production and manufacturing, water supply pumps have high electricity energy consumption costs. At present, most water supply pumps are still dispatched by on-site personnel based on experience, or they use PID (proportional-integral-differential)-based constant pressure control, ignoring the actual operating conditions of the water supply pump group, and it is difficult to effectively optimize the energy consumption of the pump group. Most of the existing water supply pump group dispatching methods guarantee the water supply volume and water supply head while reducing the conventional energy consumption of the pump group in a stable operating state to reduce production costs, but omits the transition energy efficiency of the water supply pump when it switches the operating state according to the dispatching instructions.

[0003] The existing application publication number is CN111325306A, and the invention patent is named "A method for dispatching water supply pump groups based on ABC-PSO hybrid algorithm". According to the performance and actual operating status of the individuals in the pump group, combined with the exploration ability of ABC and the solution ability of the PSO algorithm, reasonable water supply tasks are assigned to each water pump, the pressure in the official website is balanced, and the water supply flow is reduced while meeting the water comfort level, and leakage in the pipe network is reduced. The above invention patent focuses on improving the solution algorithm for the task allocation of water supply pump groups to ensure the solution efficiency and solution set accuracy, but the energy efficiency of each water pump when changing its operating state is not considered in the solution process.

[0004] The existing patent application publication number is CN110500291A, and the name is "A multi-pump parallel control method based on genetic algorithm". By establishing the pump head and power characteristic equation, the genetic algorithm is used to achieve the optimal solution of the pump system operating parameters, ensuring the flow and pressure required by the water supply system and reducing the overall operating energy consumption of the system. This invention patent proposes a variable frequency pump scheduling method for multi-pump parallel water supply systems, but ignores the fact that there are still a large number of water supply pump systems that are composed of industrial frequency pumps and variable frequency pumps in parallel, and does not include the transition energy efficiency of each pump in the calculation scope. Summary of the invention

[0005] The present invention provides an energy-saving scheduling method for a parallel water supply pump group taking transition energy efficiency into consideration. On the basis of establishing the flow-power and flow-head characteristic curves of each water supply pump in the parallel water supply pump group, a method for calculating the transition energy efficiency of the water supply pump is proposed, which takes the total transition time, total transition energy consumption and total transition water supply as the objects, and is closer to the actual energy-saving scheduling.

[0006] The technical contents of the present invention are as follows:

[0007] A method for energy-saving scheduling of parallel water supply pump groups considering transitional energy efficiency comprises the following steps:

[0008] Step 1: Access the historical operation data of the water supply pump group;

[0009] Step 2: Establishing the energy efficiency performance model of the water supply pump group considering the transition energy efficiency of the water supply pump;

[0010] Step 3: Establish an energy-saving scheduling model for the water supply pump group, complete the scheduling of pump group operation instructions and the calculation of required energy consumption;

[0011] The energy efficiency performance model of the water supply pump group considering the transition energy efficiency of the water supply pump in step 2 is composed of M industrial frequency pump energy efficiency models and N variable frequency pump energy efficiency models included in the water supply pump group, M≥0, N≥0, M+N>0.

[0012] Furthermore, the historical operation data of the water supply pump group in the step one can be accessed through an industrial production and manufacturing SCADA system, an information management system or an industrial Internet system; the historical operation data of the water supply pump group includes but is not limited to: the speed, flow, head, power of each industrial frequency water supply pump included in the pump group, the actual speed ratio, speed ratio instruction, minimum speed ratio instruction, speed, flow, head of each variable frequency water supply pump included in the pump group, one or more of the target head instruction and hourly water supply instruction of the water supply pump group.

[0013] Furthermore, the specific steps of establishing the power frequency pump energy efficiency model in step 2 are:

[0014] Step (1). For the mth power frequency pump included in the water supply pump group, when M=0, there is no power frequency pump in the parallel pump group, otherwise, m represents any one of the M power frequency pumps, m=1,2,…,M, and the parameters of the flow-power characteristic curve and the flow-head characteristic curve polynomial are calculated by fitting the historical operation data in step 1, and the polynomial expression is:

[0015] p m =a m +b m q m +c m q m 2

[0016] H m =H m,x -S m,x q m 2

[0017] In the above formula, p m Represents the power of the industrial frequency pump (in kilowatts), H m Represents lift, q mRepresents flow rate (in tons / hour), H m,x represents the virtual total head of the mth power frequency pump, S m,x represents the virtual resistance coefficient of the mth power frequency pump, a m ,b m ,c m are the fitting parameters of the polynomial of the mth power frequency pump; a, b, c have no specific names or meanings.

[0018] Step (2) for the mth power frequency pump included in the water supply pump group, using the power frequency pump power-time and flow-time information in step 1, the sampling time curve integral determines the transition energy efficiency of the power frequency pump, the transition energy efficiency includes the start-up energy efficiency and the shutdown energy efficiency;

[0019] The startup energy efficiency refers to the power frequency pump from the closed state s′ m = 0 transition to stable operation state s m = Total transition time t m,start , total transition energy consumption E m,start and transitional total water supply Q m,start ; Shutdown energy efficiency refers to the power frequency pump from the stable operation state s′ m =1 transition to closed state s m = Total transition time t m,stop , total transition energy consumption E m,stop and transitional total water supply Q m,stop ; The total transition time is measured in hours, the total transition energy consumption is measured in kilowatt-hours, and the total transition water supply is measured in tons.

[0020] Step (3). For the mth power frequency pump included in the water supply pump group, the transition efficiency of the same switch state before and after is 0, then the power frequency pump is switched from the switch state s′ m Transition to switch state s m The total transition time Δt m , total transition energy consumption ΔE m and transition total water supply ΔQ m You can use functions Express, Represents the total transition time Δt m About the switch state quantity s′ m and m The function expression of Represents the total transition energy consumption ΔE m About the switch state quantity s′ m and m The function expression of Indicates the total transition water supply ΔQ m About the switch state quantity s′ m and m The function expression is as follows:

[0021]

[0022]

[0023]

[0024] Furthermore, the specific steps of establishing the variable frequency pump energy efficiency model in step 2 are:

[0025] Step (1). For the nth variable frequency pump included in the water supply pump group, when N=0, there is no variable frequency pump in the parallel pump group. Otherwise, n represents any one of the N variable frequency pumps, n=1, 2, ..., N. The parameters of the polynomial of the flow-power characteristic curve and the flow-head characteristic curve are calculated by fitting using the historical operation data in step 1. The polynomial expression is:

[0026] p n =a n λ n 3 +b n λ n 2 q n +c n λ n q n 2

[0027] H n =H n,x λ n 2 -S n,x q n 2

[0028] In the above formula, p n Represents the power of the variable frequency pump (in kilowatts), H n Represents lift, q n Represents flow rate (in tons / hour), H n,x is the virtual total head of the variable frequency pump, S n,x is the virtual resistance coefficient of the variable frequency pump, λ n It is the ratio of the actual speed of the variable frequency pump to the rated speed, i.e. the actual speed ratio, λ min is the minimum speed ratio instruction of the variable frequency pump, speed ratio λ min ≤λ n ≤1, a n ,b n ,c n The nth variable frequency pump has a speed ratio of λ n The fitting parameters of the polynomial under ;

[0029] Step (2). For the nth variable frequency pump included in the water supply pump group, the actual speed ratio-time curve, speed ratio command-time curve, power-time curve and flow-time curve of the variable frequency pump in step 1 are used to determine the transition energy efficiency of the variable frequency pump by integrating the sampling time. The transition energy efficiency includes the startup energy efficiency, shutdown energy efficiency and speed regulation energy efficiency;

[0030] Among them, the startup energy efficiency refers to the variable frequency pump from the closed state λ′ n =0,H′ n =0 transition to the minimum speed ratio and the target stable operation head is H n The state of n =λ min ,H n >0, total transition time, total transition energy consumption and total transition water supply; shutdown energy efficiency refers to the variable frequency pump from the minimum speed ratio and stable operation head H n The state λ′ n =λ min ,H′ n >0 transition to the off stateλ n =0,H n =0, total transition time, total transition energy consumption and total transition water supply; speed regulation energy efficiency refers to the variable frequency pump from the previous speed ratio instruction to λ′ n And the stable operating head is H' n The state transitions to the next speed ratio instruction of λ n And the target stable operation head is H n The total transition time, total transition energy consumption and transition water supply of the state, λ′ n ,λ n ≥λ min ,H′ n ,H n >0; total transition time is measured in hours, total transition energy consumption is measured in kilowatt-hours, and total transition water supply is measured in tons;

[0031] Step (3). For the nth variable frequency pump included in the water supply pump group, the transition energy efficiency data in step (2) is used as the basis, and the previous speed ratio instruction λ′ is used as the basis. n , the next speed ratio command λ n , the previous stable operation head H′ S and target stable operation head H S As input, the total transition time Δt m , total transition energy consumption ΔE m and transition total water supply ΔQ m Output respectively, and establish the total transition time regression model Transition total energy consumption regression model and transition total water supply regression model The methods for constructing regression models include but are not limited to support vector machines, decision regression trees, and artificial neural networks;

[0032] Step (4). For the nth variable frequency pump included in the water supply pump group, the transition energy efficiency data in step (2) is divided into a training set and a test set in proportion, and the theoretical data of transition energy efficiency of 0 with the same speed ratio and the same working head are added to the training set to complete the total time consumption regression model of speed regulation Regression model of total power consumption of speed regulation and total water supply regression model for speed regulation Training and testing of three models. The ratio of training set to test set is usually 8:2 or 7:3.

[0033] Step (5). For the nth variable frequency pump included in the water supply pump group, the variable frequency pump has a speed ratio instruction of λ′ n And the working head H' n The state transitions to the speed ratio instruction λ n And the goal is to maintain stable operation and become H n The total transition time of the state is Δt m , total transition energy consumption ΔE m and transition total water supply ΔQ m The regression model Expressed as:

[0034]

[0035]

[0036]

[0037] Furthermore, the scheduling of the parallel water supply pump group in step 3 is specified to take effect at the hour of each hour, the scheduling instruction time interval is one hour, and the scheduling instruction content is the switch state s of each power frequency pump included in the water supply pump group in this hour. m , and the switching status of each variable frequency pump in this hour s n and speed ratio λ n When the power frequency pump or variable frequency pump is in the on state, s m or n is 1, the shutdown time is s m or n is 0, and the switching state and speed ratio of the variable frequency pump meet the speed ratio constraint:

[0038]

[0039] Furthermore, the scheduling target of the parallel water supply pump group in step 3 is to meet the target water supply of Q S(tons) and target stable working head H S Under the water supply requirements, reduce the total power consumption of the water supply pump group.

[0040] Furthermore, the specific steps of step three are:

[0041] Step (1). According to the target stable working head H of the water supply pump group this hour S , according to the parallel connection, the head constraint of the water supply pump group is established:

[0042]

[0043] Step (2). According to the switch status s′ of each power frequency pump in the water supply pump group in the previous hour m , then the power consumption of the power frequency pump under the dispatch instruction of this hour is E m (kWh) and water supply Q m (tons) can be expressed as:

[0044]

[0045]

[0046] In the above formula, p m Represents stable operation of industrial frequency pump m =1 and the head is H S The power at the time, q m Represents stable operation of industrial frequency pump m =1 and the head is H S The numerical relationship can be determined by the flow-power curve and flow-head curve polynomial expression of the power frequency pump in step 2;

[0047] Step (3). According to the switch status s′ of each variable frequency pump in the water supply pump group in the last hour n and speed ratio λ′ n , then the power consumption of the variable frequency pump under the dispatch instruction of this hour is E n (kWh) and water supply Q n (tons) can be expressed as:

[0048]

[0049]

[0050] In the above formula, p n , represents the variable frequency pump with a speed ratio of λ n , head is H S The power at the time, q n Represents the variable frequency pump at a speed ratio of λ n , head is H SThe numerical relationship can be determined by the polynomial expression of the flow-power curve and flow-head curve of the variable frequency pump in step 2;

[0051] Step (4). According to the target water supply volume Q of the water supply pump group this hour S , use the water supply expression of each water pump in step (2) and step (3) to establish the water supply constraint of the water supply pump group:

[0052]

[0053] Step (5). According to the energy saving target, the objective function of minimizing the energy consumption of the water supply pump group is established using the power consumption expressions of each water pump in steps (2) and (3):

[0054]

[0055] Step (6). Establish a heuristic algorithm solution model, substitute the objective function in step (5), the speed ratio constraint, the head constraint in step (1) and the water supply constraint in step (4) into the heuristic algorithm to calculate the switch state s of each power frequency pump in this hour. m And the switching status of each variable frequency pump in this hour n and speed ratio λ n Performing iterative solution; wherein the construction method of the heuristic algorithm includes but is not limited to genetic algorithm, annealing algorithm and particle swarm algorithm;

[0056] Step (7). Solve the switch state s of each power frequency pump in this hour that can meet the water supply head and water supply volume of the water supply pump group and has the minimum pump group energy consumption obtained in step (6). m,opt And the switching status of each variable frequency pump in this hour n,opt and speed ratio λ n,opt The operating combination parameters are used as dispatch instructions, and the minimum pump group energy consumption J is output opt , complete the water supply pump group operation instruction scheduling and required energy consumption calculation.

[0057] The beneficial effects of the present invention are as follows:

[0058] 1. The present invention establishes a water supply pump energy efficiency performance model that takes into account the transition energy efficiency of the water supply pump for industrial frequency pumps and variable frequency pumps respectively, and proposes a water supply pump transition energy efficiency calculation method based on the total transition time, total transition energy consumption and total transition water supply. By integrating the time curve and establishing a regression model based on an artificial intelligence method, the complex theoretical calculations in the transition process are avoided, and the required time, energy consumption and water supply output of each water supply pump in the transition operation state can be quantified.

[0059] 2. The present invention combines the conventional energy consumption of the water supply pump in a stable operating state with the transitional energy consumption in a changing operating state, and provides a more accurate method for calculating the energy consumption of the water supply pump. By using a heuristic algorithm, an operating parameter scheduling method is established based on the switching state of each industrial frequency pump included in the water supply pump group per hour, as well as the switching state and speed ratio of each variable frequency pump per hour. This method can ensure the water supply head and water supply volume of the water supply pump group, and achieve an energy-saving goal of the water supply pump group that is closer to actual application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 The figure is a flow chart of an energy-saving scheduling method for parallel water supply pump groups considering transitional energy efficiency. DETAILED DESCRIPTION

[0061] In order to better understand the above technical solution, further description will be given below through specific embodiments in conjunction with the accompanying drawings. It should be noted that the technical solution of the present invention includes but is not limited to the following embodiments.

[0062] Example 1

[0063] See also Figure 1 As shown, a method for energy-saving scheduling of parallel water supply pump groups considering transitional energy efficiency includes the following steps:

[0064] Step 1: Access the historical operation data of the water supply pump group;

[0065] Step 2: Establishing the energy efficiency performance model of the water supply pump group considering the transition energy efficiency of the water supply pump;

[0066] Step 3: Establish an energy-saving scheduling model for the water supply pump group, complete the scheduling of pump group operation instructions and the calculation of required energy consumption;

[0067] The energy efficiency performance model of the water supply pump group considering the transition energy efficiency of the water supply pump in step 2 is composed of M industrial frequency pump energy efficiency models and N variable frequency pump energy efficiency models included in the water supply pump group, M≥0, N≥0, M+N>0.

[0068] The present invention establishes water supply pump energy efficiency performance models that take into account the transition energy efficiency of the water supply pump for industrial frequency pumps and variable frequency pumps respectively, and proposes a water supply pump transition energy efficiency calculation method based on the total transition time, total transition energy consumption and total transition water supply. By integrating the time curve and establishing a regression model based on an artificial intelligence method, the complex theoretical calculations in the transition process are avoided, and the required time, required energy consumption and water supply output of each water supply pump in the transition operation state can be quantified.

[0069] Example 2

[0070] See also Figure 1 As shown, a method for energy-saving scheduling of parallel water supply pump groups considering transitional energy efficiency includes the following steps:

[0071] Step 1: Access the historical operation data of the water supply pump group;

[0072] The historical operation data of the water supply pump group in step 1 can be accessed through the industrial manufacturing SCADA system, information management system or industrial Internet system. The data types of the water supply pump group operation include but are not limited to: the speed, flow, head, power of each industrial frequency water supply pump included in the pump group, the actual speed ratio, speed ratio instruction, minimum speed ratio instruction, speed, flow, head of each variable frequency water supply pump included in the pump group, the target head instruction of the water supply pump group, and the hourly water supply instruction.

[0073] Step 2: Establish an energy efficiency performance model of the water supply pump group taking into account the transition energy efficiency of the water supply pump.

[0074] The energy efficiency performance model of the water supply pump group considering the transition energy efficiency of the water supply pump in step 2 is composed of M industrial frequency pump energy efficiency models and N variable frequency pump energy efficiency models included in the water supply pump group, M≥0, N≥0, M+N>0.

[0075] Furthermore, the specific steps of establishing the power frequency pump energy efficiency model in step 2 are:

[0076] Step (1). For the mth power frequency pump included in the water supply pump group, the parameters of the flow-power characteristic curve and the flow-head characteristic curve polynomial are calculated by fitting the historical operation data in step 1, and the polynomial expression is:

[0077] p m =a m +b m q m +c m q m 2

[0078] H m =H m,x -S m,x q m 2

[0079] In the above formula, p m ,H m ,q m Respectively represent the power (kW), head and flow rate (tons / hour) of the industrial frequency pump, H m,x ,S m,x are the virtual total head and virtual resistance coefficient of the mth power frequency pump, a m ,b m ,c m is the fitting parameter of the polynomial of the mth power frequency pump;

[0080] Step (2). For the mth power frequency pump included in the water supply pump group, use the power-time and flow-time information of the power frequency pump in step 1 to integrate the sampling time curve to determine the transition energy efficiency of the power frequency pump, including the start-up energy efficiency and the shutdown energy efficiency. The start-up energy efficiency refers to the transition energy efficiency of the power frequency pump from the off state s′ m = 0 transition to stable operation state s m = Total transition time t m,start , total transition energy consumption E m,start and transitional total water supply Q m,start ; Shutdown energy efficiency refers to the power frequency pump from the stable operation state s′ m =1 transition to closed state s m = Total transition time t m,stop , total transition energy consumption E m,stop and transitional total water supply Q m,stop The total transition time is measured in hours, the total transition energy consumption is measured in kilowatt-hours, and the total transition water supply is measured in tons;

[0081] Step (3). For the mth power frequency pump included in the water supply pump group, the transition efficiency of the same switch state before and after is 0, then the power frequency pump is switched from the switch state s′ m Transition to switch state s m The total transition time Δt m , total transition energy consumption ΔE m and transition total water supply ΔQ m You can use functions Expressed as:

[0082]

[0083]

[0084]

[0085] The specific steps for establishing the variable frequency pump energy efficiency model in step 2 are:

[0086] Step (1). For the nth variable frequency pump included in the water supply pump group, the parameters of the flow-power characteristic curve and the flow-head characteristic curve polynomial are calculated by fitting the historical operation data in step 1. The polynomial expression is:

[0087] p n =a n λ n 3 +b n λ n 2 q n +c n λ n q n 2

[0088] H n =H n,x λ n 2 -S n,x q n 2

[0089] In the above formula, p n ,H n ,q n Respectively represent the power (kW), head and flow rate (tons / hour) of the variable frequency pump, H n,x ,S n,x are respectively the virtual total head and virtual resistance coefficient of the variable frequency pump, λ n It is the ratio of the actual speed of the variable frequency pump to the rated speed, i.e. the actual speed ratio, λ min is the minimum speed ratio instruction of the variable frequency pump, speed ratio λ min ≤λ n ≤1, a n ,b n ,c n The nth variable frequency pump has a speed ratio of λ n The fitting parameters of the polynomial under ;

[0090] Step (2). For the nth variable frequency pump included in the water supply pump group, use the actual speed ratio-time curve, speed ratio command-time curve, power-time curve and flow-time curve of the variable frequency pump in step 1 to integrate the sampling time to determine the transition energy efficiency of the variable frequency pump, including the start-up energy efficiency, shutdown energy efficiency and speed regulation energy efficiency. Among them, the start-up energy efficiency refers to the energy efficiency of the variable frequency pump from the off state (λ′ n =0,H′ n =0) transition to the minimum speed ratio and the target stable operation head is H n The state (λ n =λ min ,H n >0), total transition time, total transition energy consumption and total transition water supply; shutdown energy efficiency refers to the frequency conversion pump from the minimum speed ratio and stable operation head H n The state (λ′ n =λ min ,H′ n >0) to the closed state (λ n =0,H n =0), total transition time, total transition energy consumption and total transition water supply; speed regulation energy efficiency refers to the speed ratio instruction of the variable frequency pump from the previous speed regulation ratio instruction to λ′ n And the stable operating head is H' n The state transitions to the next speed ratio instruction of λ n And the target stable operation head is H nThe total transition time, total transition energy consumption and transition water supply of the state, λ′ n ,λ n ≥λ min ,H′ n ,H n >0. The total transition time is measured in hours, the total transition energy consumption is measured in kilowatt-hours, and the total transition water supply is measured in tons;

[0091] Step (3). For the nth variable frequency pump included in the water supply pump group, the transition energy efficiency data in step (2) is used as the basis, and the previous speed ratio instruction λ′ is used as the basis. n , the next speed ratio command λ n , the previous stable operation head H′ S and target stable operation head H S As input, the total transition time Δt m , total transition energy consumption ΔE m and transition total water supply ΔQ m Output respectively, and establish the total transition time regression model Transition total energy consumption regression model and transition total water supply regression model The methods for constructing regression models include but are not limited to support vector machines, decision regression trees, and artificial neural networks;

[0092] Step (4). For the nth variable frequency pump included in the water supply pump group, the transition energy efficiency data in step (2) is divided into a training set and a test set in proportion, and the theoretical data of transition energy efficiency of 0 with the same speed ratio and the same working head are added to the training set to complete the total time consumption regression model of speed regulation Regression model of total power consumption of speed regulation and total water supply regression model for speed regulation Training and testing of three models. The ratio of training set to test set is usually 8:2 or 7:3.

[0093] Step (5). For the nth variable frequency pump included in the water supply pump group, the variable frequency pump has a speed ratio instruction of λ′ n And the working head H' n The state transitions to the speed ratio instruction λ n And the goal is to maintain stable operation and become H n The total transition time of the state is Δt m , total transition energy consumption ΔE m and transition total water supply ΔQ m The regression model Expressed as:

[0094]

[0095]

[0096]

[0097] Step 3: Establish an energy-saving scheduling model for the water supply pump group, complete the scheduling of the pump group operation instructions and the calculation of the required energy consumption; in step 3, the scheduling of the parallel water supply pump group is specified to take effect at the hour of each hour, the scheduling instruction time interval is one hour, and the scheduling instruction content is the switch status s of each power frequency pump included in the water supply pump group in this hour. m , and the switching status of each variable frequency pump in this hour s n and speed ratio λ n When the power frequency pump or variable frequency pump is in the on state, s m or n When the pump is stopped, it is 0, and the switching state and speed ratio of the variable frequency pump meet the speed ratio constraint:

[0098]

[0099] The scheduling goal of the parallel water supply pump group in step 3 is to meet the target water supply of Q S (tons) and target stable working head H S Under the water supply requirements, reduce the total power consumption of the water supply pump group.

[0100] The specific steps of step three are:

[0101] Step (1). According to the target stable working head H of the water supply pump group this hour S , according to the parallel connection, the head constraint of the water supply pump group is established:

[0102]

[0103] Step (2). According to the switch status s′ of each power frequency pump in the water supply pump group in the previous hour m , then the power consumption of the power frequency pump under the dispatch instruction of this hour is E m (kWh) and water supply Q m (tons) can be expressed as:

[0104]

[0105]

[0106] In the above formula, p m ,q m Represents the stable operation of the power frequency pump m =1 and the head is H S The power and flow rate at that time, the numerical relationship can be determined by the flow-power curve and flow-head curve polynomial expression of the power frequency pump in step 2;

[0107] Step (3). According to the switch status s′ of each variable frequency pump in the water supply pump group in the last hour n and speed ratio λ′ n , then the power consumption of the variable frequency pump under the dispatch instruction of this hour is E n (kWh) and water supply Q n (tons) can be expressed as:

[0108]

[0109]

[0110] In the above formula, p n ,q n Respectively represent the variable frequency pump when the speed ratio is λ n , head is H S The power and flow rate at that time, the numerical relationship can be determined by the polynomial expression of the flow-power curve and flow-head curve of the variable frequency pump in step 2;

[0111] Step (4). According to the target water supply volume Q of the water supply pump group this hour S , use the water supply expression of each water pump in step (2) and step (3) to establish the water supply constraint of the water supply pump group:

[0112]

[0113] Step (5). According to the energy saving target, the objective function of minimizing the energy consumption of the water supply pump group is established using the power consumption expressions of each water pump in steps (2) and (3):

[0114]

[0115] Step (6). Establish a heuristic algorithm solution model, substitute the objective function in step (5), the speed ratio constraint, the head constraint in step (1) and the water supply constraint in step (4) into the heuristic algorithm to calculate the switch state s of each power frequency pump in this hour. m And the switching status of each variable frequency pump in this hour n and speed ratio λ n Perform iterative solution. The construction method of the heuristic algorithm includes but is not limited to genetic algorithm, annealing algorithm and particle swarm algorithm;

[0116] Step (7). Solve the switch state s of each power frequency pump in this hour that can meet the water supply head and water supply volume of the water supply pump group and has the minimum pump group energy consumption obtained in step (6). m,opt And the switching status of each variable frequency pump in this hour n,opt and speed ratio λ n,opt The operating combination parameters are used as dispatch instructions, and the minimum pump group energy consumption J is outputopt , complete the water supply pump group operation instruction scheduling and required energy consumption calculation.

Claims

1. A method for energy-saving scheduling of parallel water supply pump groups considering transitional energy efficiency, characterized in that: The steps include: Step 1: Access the historical operation data of the water supply pump group; Step 2: Establishing the energy efficiency performance model of the water supply pump group considering the transition energy efficiency of the water supply pump; Step 3: Establish an energy-saving scheduling model for the water supply pump group, complete the scheduling of pump group operation instructions and the calculation of required energy consumption; The energy efficiency performance model of the water supply pump group considering the transition energy efficiency of the water supply pump in step 2 is composed of M power frequency pump energy efficiency models and N variable frequency pump energy efficiency models included in the water supply pump group, M≥0,≥0,+N>0; The specific steps of establishing the power frequency pump energy efficiency model in step 2 are: Step (1). For the mth power frequency pump included in the water supply pump group, representing any one of the M power frequency pumps, m = 1, 2, ..., M, the parameters of the flow-power characteristic curve and the flow-head characteristic curve polynomial are calculated by fitting the historical operation data in step 1, and the polynomial expression is: p m =a m +b m q m +c m q m 2 H m =H m,x -S m,x q m 2 In the above formula, p m Represents the power of the industrial frequency pump (in kilowatts), H m Represents lift, q m represents the flow rate (in tons / hour), m,x represents the virtual total head of the mth power frequency pump, S m,x represents the virtual resistance coefficient of the mth power frequency pump, a m ,b m ,c m is the fitting parameter of the polynomial of the mth power frequency pump; Step (2) for the mth power frequency pump included in the water supply pump group, using the power frequency pump power-time and flow-time information in step 1, the sampling time curve integral determines the transition energy efficiency of the power frequency pump, the transition energy efficiency includes the start-up energy efficiency and the shutdown energy efficiency; The startup energy efficiency refers to the power frequency pump from the closed state s′ m = 0 transition to stable operation state s m = Total transition time t m,start , total transition energy consumption E m,start and transition total water supply Q m,start ; Shutdown energy efficiency refers to the power frequency pump from the stable operation state s′ m =1 transition to closed state s m = Total transition time t m,stop , total transition energy consumption E m,tnop and transitional total water supply Q m,top ; Step (3). For the mth power frequency pump included in the water supply pump group, the over-efficiency of the same switch state before and after is 0, then the power frequency pump is switched from the switch state s′ s Transition to switch state s m The total transition time Δt m , total transition energy consumption ΔE m and transition total water supply ΔQ m You can use functions Express, Represents the total transition time Δt m About the switch state quantity s′ m and m The function expression of Represents the total transition energy consumption ΔE m About the switch state quantity s′ m and m The function expression of Indicates the total transition water supply ΔQ m About the switch state quantity s′ m and m The function expression is as follows: The specific steps of establishing the variable frequency pump energy efficiency model in step 2 are: Step (1). For the nth variable frequency pump included in the water supply pump group, which represents any one of the N variable frequency pumps, n = 1, 2, ..., N, the parameters of the flow-power characteristic curve and the flow-head characteristic curve polynomial are calculated by fitting the historical operation data in step 1. The polynomial expression is: p n =a n l n 3 +b n l n 2 q n +c n l n q n 2 H n =H n,x λ n 2 -S n,x q n 2 In the above formula, p n Represents the power of the variable frequency pump, H n Represents lift, q n represents the flow rate, n,x is the virtual total head of the variable frequency pump, S n,x is the virtual resistance coefficient of the variable frequency pump, λ n It is the ratio of the actual speed of the variable frequency pump to the rated speed, i.e. the actual speed ratio, λ min is the minimum speed ratio instruction of the variable frequency pump, speed ratio λ min ≤λ n ≤1, a n ,b n ,c n The nth variable frequency pump has a speed ratio of λ n The fitting parameters of the polynomial under ; Step (2). For the nth variable frequency pump included in the water supply pump group, the actual speed ratio-time curve, speed ratio command-time curve, power-time curve and flow-time curve of the variable frequency pump in step 1 are used to determine the transition energy efficiency of the variable frequency pump by integrating the sampling time. The transition energy efficiency includes the startup energy efficiency, shutdown energy efficiency and speed regulation energy efficiency; Among them, the startup energy efficiency refers to the variable frequency pump from the closed state λ′ n =0,H′ n =0 transition to the minimum speed ratio and the target stable operation head is H n The state of n =λ min ,H n >0, total transition time, total transition energy consumption and total transition water supply; shutdown energy efficiency refers to the frequency conversion pump from the minimum speed ratio and stable operation head H n The state λ′ n =λ min ,H′ n >0 transition to the closed state λ n =0,H n =0, the total transition time, total transition energy consumption and total transition water supply; the speed regulation energy efficiency refers to the variable frequency pump from the previous speed regulation ratio instruction to λ′ n And the stable operating head is H' n The state transitions to the next speed ratio instruction of λ n And the target stable operation head is H n The total transition time, total transition energy consumption and transition water supply of the state, λ′ n ,λ n ≥λ min ,H′ n ,H n >0; total transition time is measured in hours, total transition energy consumption is measured in kilowatt-hours, and total transition water supply is measured in tons; Step (3). For the nth variable frequency pump included in the water supply pump group, the transition energy efficiency data in step (2) is used as the basis, and the previous speed ratio instruction λ′ is used as the basis. n , the next speed ratio command λ n , the previous stable operation head H′ S and target stable operation head H S As input, the total transition time Δt m , total transition energy consumption ΔE m and transition total water supply ΔQ m Output respectively, and establish the total transition time regression model Transition total energy consumption regression model and transition total water supply regression model Step (4). For the nth variable frequency pump included in the water supply pump group, the transition energy efficiency data in step (2) is divided into a training set and a test set in proportion, and the theoretical data of transition energy efficiency of 0 with the same speed ratio and the same working head are added to the training set to complete the total time consumption regression model of speed regulation Regression model of total power consumption of speed regulation and total water supply regression model for speed regulation Training and testing of three models; Step (5). For the nth variable frequency pump included in the water supply pump group, the variable frequency pump has a speed ratio instruction of λ′ n And the working head H' n The state transitions to the speed ratio instruction of λ n And the goal is to maintain stable operation and become H n The total transition time of the state is Δt m , total transition energy consumption ΔE m and transition total water supply ΔQ m The regression model Expressed as: In step 3, the scheduling of the parallel water supply pump group is specified to take effect at the hour of each hour, the scheduling instruction interval is one hour, and the scheduling instruction content is the switch status s of each power frequency pump included in the water supply pump group in this hour. m , and the switching status of each variable frequency pump in this hour s n and speed ratio λ n When the power frequency pump or variable frequency pump is in the on state, s m or n is 1, the shutdown time is s m or n is 0, and the switching state and speed ratio of the variable frequency pump meet the speed ratio constraint: The specific steps of step three are: Step (1). According to the target stable working head H of the water supply pump group this hour S , according to the parallel connection, the head constraint of the water supply pump group is established: Step (2). According to the switch status s′ of each power frequency pump in the water supply pump group in the previous hour m , then the power consumption of the power frequency pump under the dispatch instruction of this hour is E m and water supply Q m It can be expressed as: In the above formula, p m Represents stable operation of the power frequency pump m =1 and the head is H S The power at m Represents stable operation of the power frequency pump m =1 and the head is H S The numerical relationship can be determined by the flow-power curve and flow-head curve polynomial expression of the power frequency pump in step 2; Step (3). According to the switch status s′ of each variable frequency pump in the water supply pump group in the last hour n and speed ratio λ′ n , then the power consumption of the variable frequency pump under the dispatch instruction of this hour is E n and water supply Q n It can be expressed as: In the above formula, p n , represents the variable frequency pump with a speed ratio of λ n , head is H S The power at the time, q n Represents the variable frequency pump at a speed ratio of λ n , head is H S The numerical relationship can be determined by the polynomial expression of the flow-power curve and flow-head curve of the variable frequency pump in step 2; Step (4). According to the target water supply volume Q of the water supply pump group this hour S , use the water supply expression of each water pump in step (2) and step (3) to establish the water supply constraint of the water supply pump group: Step (5). According to the energy saving target, the objective function of minimizing the energy consumption of the water supply pump group is established using the power consumption expressions of each water pump in steps (2) and (3): Step (6). Establish a heuristic algorithm solution model, substitute the objective function in step (5), the speed ratio constraint, the head constraint in step (1) and the water supply constraint in step (4) into the heuristic algorithm to calculate the switch state s of each power frequency pump in this hour. m And the switching status of each variable frequency pump in this hour n and speed ratio λ n Perform iterative solution; Step (7). Solve the switch state s of each power frequency pump in this hour that can meet the water supply head and water supply volume of the water supply pump group and has the minimum pump group energy consumption obtained in step (6). m,opt And the switching status of each variable frequency pump in this hour n,opt and speed ratio λ n,opt The operating combination parameters are used as dispatch instructions, and the minimum pump group energy consumption J is output opt , complete the water supply pump group operation instruction scheduling and required energy consumption calculation.

2. The energy-saving scheduling method for parallel water supply pump groups considering transitional energy efficiency according to claim 1 is characterized in that: The historical operation data of the water supply pump group in the step one is accessed through the industrial production and manufacturing SCADA system, information management system or industrial Internet system; the historical operation data types of the water supply pump group include: the speed, flow, head, power of each industrial frequency water supply pump included in the pump group, the actual speed ratio, speed ratio instruction, minimum speed ratio instruction, speed, flow, head of each variable frequency water supply pump included in the pump group, one or more of the target head instruction and hourly water supply instruction of the water supply pump group.

3. The energy-saving scheduling method for parallel water supply pump groups considering transitional energy efficiency according to claim 1 is characterized in that: The scheduling goal of the parallel water supply pump group in step 3 is to meet the target water supply of Q S And target stable working head H S Under the water supply requirements, reduce the total power consumption of the water supply pump group.

4. The energy-saving scheduling method for parallel water supply pump groups considering transitional energy efficiency according to claim 1 is characterized in that: The regression model is constructed by a method including a support vector machine, a decision regression tree or an artificial neural network.

5. The energy-saving scheduling method for parallel water supply pump groups considering transitional energy efficiency according to claim 1 is characterized in that: The ratio of the training set to the test set is 8:2 or 7:

3.

6. The energy-saving scheduling method for parallel water supply pump groups considering transitional energy efficiency according to claim 1 is characterized in that: The construction methods of heuristic algorithms include genetic algorithm, annealing algorithm and particle swarm algorithm.

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