A circulating water pump control method and system based on real-time power optimization

Abstract

The present invention relates to the technical field of liquid pumps, and discloses a circulating water pump control method and system based on real-time power optimization, including collecting the real-time power of the boiler; determining the control flow of each water supply circulating water pump according to the set power and the real-time power; controlling the operation of each water supply circulating water pump according to the control flow; after the real-time power changes, establishing an objective function with the goal of minimizing the sum of flow changes of the water supply circulating water pump; solving the objective function to obtain the regulated flow; and controlling the operation of the water supply circulating water pump according to the regulated flow. This method determines the flow of each circulating water pump according to the power ratio at the initial stage of control, and after the power changes, determines the optimal flow with the goal of minimizing the sum of flow changes of all circulating water pumps, so that the circulating water pump can quickly adapt to the change in power, thereby making each boiler always work in the best state and maximizing the use of energy.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid pumps, and in particular to a circulating water pump control method and system based on real-time power optimization. Background Art

[0002] Central heating is a common heating method in winter. Heating companies input high-temperature media, such as water or steam, into the primary network. After heat exchange at the heat exchange station, the heat is transferred to the secondary network and finally transmitted to the user's room. There are two main heat sources used by heating companies, one is the waste heat from the power plant, and the other is boiler heating. The latter is currently the main heat source. The boiler can heat the water in the primary network to about 130 degrees Celsius. After heat exchange in the heat exchanger, the return water of the primary network is about 70 degrees Celsius. These return waters are transported to the boiler again through the circulating water pump and heated again, realizing the recycling of water.

[0003] Although coal-fired boilers still account for a large proportion of all boilers, cleaner and more economical energy sources are gradually being applied to heating. These emerging energy sources have the advantages of being renewable, low-pollution and cheap, and the application of these energy sources is expected to reduce the costs of heating companies. However, after the addition of new energy sources, it is necessary to adjust the existing coal-fired boiler usage strategy, especially the state control of the circulating water pump. If the control strategy of the circulating water pump is selected incorrectly, the maximum value of the emerging energy may not be brought into play, resulting in energy waste. Summary of the invention

[0004] In view of the above existing problems, the present invention is proposed.

[0005] Therefore, the present invention provides a circulating water pump control method based on real-time power optimization, which can solve the problem in the prior art that incorrect selection of circulating water pump control strategy will lead to energy waste.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions, a circulating water pump control method based on real-time power optimization, comprising: collecting the real-time power of the first electric boiler and the second electric boiler; determining the control flow according to the set power and the collected real-time power, and controlling the corresponding water supply circulating water pump to perform layered work; when the real-time power changes, establishing an objective function with the minimum sum of the flow changes of the water supply circulating water pump as the goal, and setting constraints at the same time; using a genetic algorithm to solve the objective function to obtain the regulated flow corresponding to the water supply circulating water pump; and synchronously adjusting the operation of the water supply circulating water pump according to the obtained regulated flow.

[0007] As a preferred solution of the circulating water pump control method based on real-time power optimization described in the present invention, wherein: the real-time power of the first electric boiler and the second electric boiler is collected, including: connecting a current transformer in series in the power supply line of the electric boiler to measure the current in a non-invasive manner, connecting a voltage sensor in parallel to the power supply line of the electric boiler to measure the voltage, setting a data collector, and transmitting data wirelessly; the data collector reads the current and voltage values ​​at a sampling frequency of once every 30 seconds;

[0008] Calculate the real-time power: real-time power = real-time voltage × real-time current × power factor, where the coal-fired boiler and the first electric boiler and the second electric boiler supply heat at the same time, and the hot water output by the coal-fired boiler, the first electric boiler and the second electric boiler are all supplied to the heat exchanger, and the coal-fired boiler always operates at the set power.

[0009] As a preferred solution of the circulating water pump control method based on real-time power optimization described in the present invention, wherein: the control flow rate is determined including: according to the set power , first real-time power and the second real-time power Determine the control flow rates of the first water supply circulating water pump, the second water supply circulating water pump and the third water supply circulating water pump to obtain a first control flow rate, a second control flow rate and a third control flow rate respectively;

[0010] According to the real-time power of the first electric boiler and the second electric boiler and the set power of the coal-fired boiler, the power proportion of each boiler is calculated:

[0011]

[0012]

[0013]

[0014] in, Respectively represent the power proportions of coal-fired boilers, the first electric boiler, and the second electric boiler;

[0015] Establish the relationship between power and flow. The power of each boiler is proportional to the flow. Use the power ratio as the flow ratio:

[0016]

[0017]

[0018]

[0019] The final control flow is:

[0020]

[0021]

[0022]

[0023] in, Indicates the proportional coefficient of the hot water flow rate of each boiler, They represent the control flow of the coal-fired boiler, the first electric boiler and the second electric boiler respectively. Indicates the total flow.

[0024] As a preferred solution of the circulating water pump control method based on real-time power optimization described in the present invention, the layered work includes initializing the rotation speeds of the first water supply circulating water pump, the second water supply circulating water pump and the third water supply circulating water pump so that the output flow rate is equal to the calculated control flow rate;

[0025] Monitor the power of the first electric boiler, the second electric boiler and the coal-fired boiler, as well as the actual flow of the first water supply circulating pump, the second water supply circulating pump and the third water supply circulating pump in real time, compare the actual flow with the calculated control flow, calculate the deviation, and adjust the speed of the water pump according to the deviation;

[0026] When the power fluctuation of the first electric boiler or the second electric boiler exceeds the set threshold, the power proportion is adjusted according to the fluctuation direction, and the control flow of the water supply circulation pump is adjusted at the same time;

[0027] When the power fluctuation of the coal-fired boiler exceeds the set threshold, the power proportion is adjusted, and the control flow of the water supply circulation pump is adjusted at the same time;

[0028] When the system operates in energy-saving mode, the power ratio of the first electric boiler and the second electric boiler is adjusted according to the energy-saving strategy, and the control flow of the water supply circulation pump is adjusted at the same time.

[0029] As a preferred embodiment of the circulating water pump control method based on real-time power optimization described in the present invention, the establishment of the objective function includes, after the first real-time power and the second real-time power change, establishing the objective function with the minimum sum of the flow rate changes of the first water supply circulating water pump, the second water supply circulating water pump and the third water supply circulating water pump as the goal,

[0030]

[0031] Where i is the number of the coal-fired boiler, the first electric boiler and the second electric boiler, i=1, 2, 3 represent the coal-fired boiler, the first electric boiler and the second electric boiler respectively, Indicates the control flow of the water supply circulation pump connected to the corresponding boiler. Indicates the regulated flow rate of the water supply circulation pump connected to the corresponding boiler;

[0032] The constraints are:

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

[0039] Among them, Q 总 Indicates the total flow, It indicates the maximum flow rate of the water supply circulation pump connected to the corresponding boiler, c indicates the specific heat capacity of water, Indicates the mass flow rate of the water supply circulating pump connected to the corresponding boiler before adjustment. Indicates the mass flow rate after adjustment of the water supply circulating pump connected to the corresponding boiler. Indicates the temperature difference between the boiler input water and output water. and They represent the power of the boiler before and after the change respectively, and ρ is the density of water.

[0040] As a preferred solution of the circulating water pump control method based on real-time power optimization described in the present invention, wherein: the use of a genetic algorithm to solve the objective function includes randomly generating N individuals, each individual containing n=9 genes, representing a combination of regulating flow rates of the water supply circulating water pumps of three boilers;

[0041] For each individual, calculate the multi-objective fitness:

[0042]

[0043] in, represents the multi-objective fitness, represents the energy consumption function;

[0044] Use non-dominated sorting to evaluate the Pareto rank of individuals, select based on the Pareto rank and crowding distance of individuals, and maintain the diversity of the population:

[0045]

[0046] in, represents the current population, represents the Pareto dominance relationship, Indicates other individuals Adaptability;

[0047] The crossover rate is adjusted by the average fitness and optimal fitness of the current population, and the selected individuals are crossovered to generate new individuals:

[0048]

[0049] in, represents the crossover rate of the current iteration, represents the initial crossover rate, represents the initial crossover rate, Indicates the best fitness in the current population;

[0050] Adjust the mutation step length according to the number of iterations and the maximum number of iterations, and perform mutation operations on the new individuals after crossover:

[0051]

[0052] in, Indicates The variable asynchronous length of the iteration, represents the initial step length, represents the maximum number of iterations, Represents the parameter that controls the step size decrease rate;

[0053] Adjust the mutation rate according to the average fitness and the best fitness of the population:

[0054]

[0055] in, Indicates the current iteration mutation rate, represents the initial mutation rate;

[0056] The newly generated individuals are merged with the original population, and the merged population is selected using non-dominated sorting and crowding distance to form a new generation of population. In each generation, a certain number of elite individuals, that is, individuals with the smallest objective function value in the previous population, are retained and directly enter the next generation to update the optimal population. When the objective function value of an individual in the new population is less than the objective function value of the worst individual in the current optimal population, the worst individual in the optimal population is replaced by the new individual. When the objective function value of the best individual in the new population is less than the objective function value of the best individual in the current optimal population, the optimal population is updated.

[0057] Assume J is the size of the elite population, P is the current population, and P' is the new population, then:

[0058]

[0059] in, represents the elite population, Indicates sorting the collection. [: J ] Indicates taking the first J individuals after sorting;

[0060] Calculate the objective function value of the new population. When the objective function value of the best individual in the new population is less than that of the best population, The objective function value of the best individual in , then update the optimal population:

[0061]

[0062] in, represents the best individual in the new population, Represents the individual with the largest objective function value;

[0063] When the individual in the new population is better than the worst individual in the optimal population, it is replaced; the algorithm stops when one of the following conditions is met:

[0064] When the preset maximum number of iterations is reached, the objective function value reaches the preset threshold, and the optimal objective function value of consecutive generations has not been significantly improved; after the algorithm stops, the optimal population is output .

[0065] As a preferred solution of the circulating water pump control method based on real-time power optimization described in the present invention, wherein: the synchronous regulation of the water supply circulating water pump operation includes defining It is the sum of the ratios of the flow rate changes of each pump monitored in real time to the total flow rate change:

[0066]

[0067] in, represents the dynamic flow balance index, Respectively represent the flow rate changes of three different water pumps, It represents the sum of the flow changes of all pumps. When , the traffic redistribution mechanism is triggered;

[0068] EEWC is defined as the sum of the ratios of the power change before and after each pump is adjusted to the total power change:

[0069]

[0070] in, represents the energy efficiency fluctuation coefficient, Respectively represent the power changes of three different water pumps before and after adjustment, It represents the sum of the power changes of all pumps;

[0071] when The following adjustment strategies are implemented:

[0072] Calculate the power change rate of each pump , Indicates the initial power of pump i, and the one with the largest pumps; calculate the energy efficiency change rate of each pump , adjust the corresponding water pump in the order of energy efficiency change rate from large to small, and dynamically adjust according to historical operation data and current working conditions ;

[0073] Calculate the rate of change of temperature difference:

[0074]

[0075] in, represents the average input and output water temperature difference in the initial state, represents the input and output water temperature difference of the i-th boiler. When , start the temperature difference compensation adjustment strategy;

[0076] when and When , only the pump flow rate is adjusted, and other system parameters remain unchanged; when and When the water pump with the best energy efficiency is adjusted first, the adjustment of other water pumps shall be considered; when When the temperature difference compensation adjustment strategy is activated, the working status of all water pumps is adjusted to ensure the stable operation of the system. When multiple adjustment requirements conflict, the priority order is .

[0077] Another object of the present invention is to provide a circulating water pump control system based on real-time power optimization, which can efficiently and accurately control the heat distribution generated by different energy sources and the working state of the circulating water pump to achieve optimal utilization of thermal energy and minimize energy consumption.

[0078] As a preferred solution of the circulating water pump control system based on real-time power optimization described in the present invention, it includes: a data acquisition module, a real-time power calculation module, a control flow determination module, a hierarchical work control module, and an objective function solution module;

[0079] The data acquisition module collects the current and voltage data in the power supply line of the electric boiler in real time to provide basic data for subsequent power calculation;

[0080] The real-time power calculation module calculates the real-time power of the electric boiler based on the collected current and voltage data;

[0081] The control flow determination module determines the control flow of each water supply circulation pump according to the real-time power and the set power to ensure that the heating ratio of each boiler matches the power ratio;

[0082] The stratified operation control module realizes stratified operation control of the water supply circulation pump by adjusting the rotation speed of the water pump to ensure the stable operation of the system;

[0083] The objective function solving module solves the objective function through a genetic algorithm to find the optimal flow rate adjustment combination and realize accurate control of the water supply circulation pump.

[0084] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and is characterized in that when the processor executes the computer program, the processor implements the steps of a circulating water pump control method based on real-time power optimization.

[0085] A computer-readable storage medium stores a computer program, wherein when the computer program is executed by a processor, the computer program implements the steps of a circulating water pump control method based on real-time power optimization.

[0086] Beneficial effects of the present invention: This method determines the flow rate of each circulating water pump according to the power ratio in the initial control stage, and after the power changes, the optimal flow rate is determined with the goal of minimizing the sum of the flow rate changes of all circulating water pumps, so that the circulating water pump can quickly adapt to the change in power, thereby making each boiler always work in the best state, maximizing the use of energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0087] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0088] Figure 1 A schematic flow chart of a circulating water pump control method based on real-time power optimization provided by an embodiment of the present invention.

[0089] Figure 2 A schematic diagram of working modules of a circulating water pump control system based on real-time power optimization provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0090] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0091] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0092] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments.

[0093] The present invention is described in detail with reference to schematic diagrams. When describing the embodiments of the present invention, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0094] At the same time, in the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper, lower, inner and outer" are based on the directions or positional relationships shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0095] In the present invention, unless otherwise clearly specified and limited, the terms "install, connect, connect" should be understood in a broad sense, for example: it can be a fixed connection, a detachable connection or an integral connection; it can also be a mechanical connection, an electrical connection or a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0096] Example 1, reference Figure 1 , which is the first embodiment of the present invention, and provides a circulating water pump control method based on real-time power optimization, comprising:

[0097] S1: Collect the real-time power of the first electric boiler and the second electric boiler.

[0098] Furthermore, the real-time power collection of the first electric boiler and the second electric boiler includes: connecting a current transformer in series in the power supply line of the electric boiler to measure the current in a non-invasive manner, connecting a voltage sensor in parallel to the power supply line of the electric boiler to measure the voltage, setting a data collector, and transmitting data wirelessly; the data collector reads the current and voltage values ​​at a sampling frequency of once every 30 seconds;

[0099] Calculate the real-time power: real-time power = real-time voltage × real-time current × power factor, where the coal-fired boiler and the first electric boiler and the second electric boiler supply heat at the same time, and the hot water output by the coal-fired boiler, the first electric boiler and the second electric boiler are all supplied to the heat exchanger, and the coal-fired boiler always operates at the set power.

[0100] S2: Determine the control flow rate according to the set power and the collected real-time power, and control the corresponding water supply circulation pump to work in layers.

[0101] Furthermore, the control flow rate is determined by setting the power , first real-time power and the second real-time power Determine the control flow rates of the first water supply circulating water pump, the second water supply circulating water pump and the third water supply circulating water pump to obtain a first control flow rate, a second control flow rate and a third control flow rate respectively;

[0102] According to the real-time power of the first electric boiler and the second electric boiler and the set power of the coal-fired boiler, the power proportion of each boiler is calculated:

[0103]

[0104]

[0105]

[0106] in, Respectively represent the power proportions of coal-fired boilers, the first electric boiler, and the second electric boiler;

[0107] Establish the relationship between power and flow. The power of each boiler is proportional to the flow. Use the power ratio as the flow ratio:

[0108]

[0109]

[0110]

[0111] The final control flow is:

[0112]

[0113]

[0114]

[0115] in, Indicates the proportional coefficient of the hot water flow rate of each boiler, They represent the control flow of the coal-fired boiler, the first electric boiler and the second electric boiler respectively. Indicates the total flow.

[0116] It should be noted that the stratification work includes initializing the rotation speeds of the first water supply circulation pump, the second water supply circulation pump and the third water supply circulation pump so that the output flow rate is equal to the calculated control flow rate;

[0117] Monitor the power of the first electric boiler, the second electric boiler and the coal-fired boiler, as well as the actual flow of the first water supply circulating pump, the second water supply circulating pump and the third water supply circulating pump in real time, compare the actual flow with the calculated control flow, calculate the deviation, and adjust the speed of the water pump according to the deviation;

[0118] When the power fluctuation of the first electric boiler or the second electric boiler exceeds the set threshold, the power proportion is adjusted according to the fluctuation direction, and the control flow of the water supply circulation pump is adjusted at the same time;

[0119] When the power fluctuation of the coal-fired boiler exceeds the set threshold, the power proportion is adjusted, and the control flow of the water supply circulation pump is adjusted at the same time;

[0120] When the system operates in energy-saving mode, the power ratio of the first electric boiler and the second electric boiler is adjusted according to the energy-saving strategy, and the control flow of the water supply circulation pump is adjusted at the same time.

[0121] S3: When the real-time power changes, the objective function is established with the goal of minimizing the sum of the flow changes of the water supply circulation pump, and constraints are set at the same time.

[0122] Furthermore, the establishing of the objective function includes establishing the objective function with the goal of minimizing the sum of flow rate changes of the first water supply circulating water pump, the second water supply circulating water pump and the third water supply circulating water pump after the first real-time power and the second real-time power change.

[0123]

[0124] Where i is the number of the coal-fired boiler, the first electric boiler and the second electric boiler, i=1, 2, 3 represent the coal-fired boiler, the first electric boiler and the second electric boiler respectively, Indicates the control flow of the water supply circulation pump connected to the corresponding boiler. Indicates the regulated flow rate of the water supply circulation pump connected to the corresponding boiler;

[0125] The constraints are:

[0126]

[0127]

[0128]

[0129]

[0130]

[0131]

[0132] Among them, Q 总 Indicates the total flow, It indicates the maximum flow rate of the water supply circulation pump connected to the corresponding boiler, c indicates the specific heat capacity of water, Indicates the mass flow rate of the water supply circulating pump connected to the corresponding boiler before adjustment. Indicates the mass flow rate after adjustment of the water supply circulating pump connected to the corresponding boiler. Indicates the temperature difference between the boiler input water and output water. and They represent the power of the boiler before and after the change respectively, and ρ is the density of water.

[0133] S4: Use genetic algorithm to solve the objective function and obtain the regulated flow corresponding to the water supply circulation pump.

[0134] Furthermore, the use of a genetic algorithm to solve the objective function includes randomly generating N individuals, each of which contains n=9 genes, representing a combination of regulating flow rates of water supply circulating pumps of three boilers;

[0135] For each individual, calculate the multi-objective fitness:

[0136]

[0137] in, represents the multi-objective fitness, represents the energy consumption function;

[0138] Use non-dominated sorting to evaluate the Pareto rank of individuals, select based on the Pareto rank and crowding distance of individuals, and maintain the diversity of the population:

[0139]

[0140] in, represents the current population, represents the Pareto dominance relationship, Indicates other individuals Adaptability;

[0141] The crossover rate is adjusted by the average fitness and optimal fitness of the current population, and the selected individuals are crossovered to generate new individuals:

[0142]

[0143] in, represents the crossover rate of the current iteration, represents the initial crossover rate, represents the initial crossover rate, Indicates the best fitness in the current population;

[0144] Adjust the mutation step length according to the number of iterations and the maximum number of iterations, and perform mutation operations on the new individuals after crossover:

[0145]

[0146] in, Indicates The variable asynchronous length of the iteration, represents the initial step length, represents the maximum number of iterations, Represents the parameter that controls the step size decrease rate;

[0147] Adjust the mutation rate according to the average fitness and the best fitness of the population:

[0148]

[0149] in, Indicates the current iteration mutation rate, represents the initial mutation rate;

[0150] The newly generated individuals are merged with the original population, and the merged population is selected using non-dominated sorting and crowding distance to form a new generation of population. In each generation, a certain number of elite individuals, that is, individuals with the smallest objective function value in the previous population, are retained and directly enter the next generation to update the optimal population. When the objective function value of an individual in the new population is less than the objective function value of the worst individual in the current optimal population, the worst individual in the optimal population is replaced by the new individual. When the objective function value of the best individual in the new population is less than the objective function value of the best individual in the current optimal population, the optimal population is updated.

[0151] Assume J is the size of the elite population, P is the current population, and P' is the new population, then:

[0152]

[0153] in, represents the elite population, Indicates sorting the collection. [: J ] Indicates taking the first J individuals after sorting;

[0154] Calculate the objective function value of the new population. When the objective function value of the best individual in the new population is less than that of the best population, The objective function value of the best individual in , then update the optimal population:

[0155]

[0156] in, represents the best individual in the new population, Represents the individual with the largest objective function value;

[0157] When the individual in the new population is better than the worst individual in the optimal population, it is replaced; the algorithm stops when one of the following conditions is met:

[0158] When the preset maximum number of iterations is reached, the objective function value reaches the preset threshold, and the optimal objective function value of consecutive generations has not been significantly improved; after the algorithm stops, the optimal population is output .

[0159] S5: According to the obtained regulated flow rate, the water supply circulation pump is synchronously regulated to operate.

[0160] Furthermore, the synchronous regulation of the water supply circulation pump includes defining DFBI as the sum of the ratios of the flow rate changes of each pump monitored in real time to the total flow rate change:

[0161]

[0162] in, represents the dynamic flow balance index, Respectively represent the flow rate changes of three different water pumps, It represents the sum of the flow changes of all pumps. When , the traffic redistribution mechanism is triggered;

[0163] EEWC is defined as the sum of the ratios of the power change before and after each pump is adjusted to the total power change:

[0164]

[0165] in, represents the energy efficiency fluctuation coefficient, Respectively represent the power changes of three different water pumps before and after adjustment, It represents the sum of the power changes of all pumps;

[0166] when The following adjustment strategies are implemented:

[0167] Calculate the power change rate of each pump , Indicates the initial power of pump i, and the one with the largest pumps; calculate the energy efficiency change rate of each pump , adjust the corresponding water pump in the order of energy efficiency change rate from large to small, and dynamically adjust according to historical operation data and current working conditions ;

[0168] Calculate the rate of change of temperature difference:

[0169]

[0170] in, represents the average input and output water temperature difference in the initial state, represents the input and output water temperature difference of the i-th boiler. When , start the temperature difference compensation adjustment strategy;

[0171] when and When , only the pump flow rate is adjusted, and other system parameters remain unchanged; when and When the water pump with the best energy efficiency is adjusted first, the adjustment of other water pumps shall be considered; when When the temperature difference compensation adjustment strategy is activated, the working status of all water pumps is adjusted to ensure the stable operation of the system. When multiple adjustment requirements conflict, the priority order is .

[0172] Example 2 is an embodiment of the present invention, which provides a circulating water pump control method based on real-time power optimization. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through experiments.

[0173] S100, collecting the real-time power of the first electric boiler and the second electric boiler, and obtaining the first real-time power and the second real-time power respectively; wherein the coal-fired boiler and the first electric boiler and the second electric boiler supply heat at the same time, and the hot water output by the coal-fired boiler, the first electric boiler and the second electric boiler are all supplied to the heat exchanger, and the coal-fired boiler always operates at the set power.

[0174] The heat exchanger is installed in the heat exchange station. The hot water with a temperature of about 130 degrees Celsius output by each boiler is input into the heat exchanger through the water supply circulation pump, and the heat is transferred to the secondary network. The temperature is reduced to about 70 degrees Celsius, forming return water and returning to the input end of the boiler, realizing the recycling of water.

[0175] During the power supply process, the voltage detection unit and the current detection unit will detect the voltage and current of the boiler respectively, determine the real-time power based on the voltage and current, and compare the real-time power with the rated power. If the real-time power exceeds the rated power, the current will be limited to reduce the real-time power to the rated power or below. While ensuring that the real-time power of the electric boiler does not exceed the rated power, the product of the current and voltage of the electric boiler is used as the corresponding real-time power. The coal-fired boiler itself has a certain heating power, and in subsequent work, the coal-fired boiler will continue to work at the set power. The purpose of this application is to achieve the regulation of the flow of each water supply circulation pump without actively changing the power of each boiler.

[0176] S110, determining the control flow rates of the first water supply circulating water pump 100, the second water supply circulating water pump 200 and the third water supply circulating water pump 300 according to the set power, the first real-time power and the second real-time power, and obtaining the first control flow rate, the second control flow rate and the third control flow rate respectively; wherein the first water supply circulating water pump 100, the second water supply circulating water pump 200 and the third water supply circulating water pump 300 are respectively connected to the output ends of the coal-fired boiler, the first electric boiler and the second electric boiler.

[0177] Exemplarily, when the present application determines the first control flow, the second control flow and the third control flow, the ratio of the set power, the first real-time power and the second real-time power is first determined, and then the total flow is divided into the first control flow, the second control flow and the third control flow according to the ratio; wherein the total flow is the sum of the flows of the first water supply circulating water pump 100, the second water supply circulating water pump 200 and the third water supply circulating water pump 300.

[0178] The above-mentioned total flow rate can remain unchanged under any circumstances. At this time, in order to ensure that the heat output through the heat exchanger remains unchanged, the return water temperature of each boiler will also remain unchanged, so the temperature difference between the supply and return water is maintained at about 60 degrees Celsius. Of course, the total flow rate can also change to a certain extent, but it is necessary to ensure that the heat output through the heat exchanger remains unchanged. At this time, it is necessary to appropriately reduce the temperature difference between the supply and return water when the total flow rate increases, and reducing the temperature difference can be achieved by increasing the control flow rate of each water supply circulating water pump. When the flow rate of the water supply circulating water pump increases, the total flow rate will increase, but when the power of the boiler remains unchanged, the temperature difference between the boiler output water and the input water will decrease, that is, when the return water temperature remains unchanged or slightly reduced, the supply water temperature will be greatly reduced, achieving the purpose of reducing the supply and return water temperature difference.

[0179] Regardless of whether the total flow rate changes, the total flow rate will be the sum of the flow rates of each water supply circulating pump.

[0180] Furthermore, the input ends of the coal-fired boiler, the first electric boiler and the second electric boiler are respectively connected to the first return water circulation pump 110, the second return water circulation pump 210 and the third return water circulation pump 310, and the flow rates of the first return water circulation pump 110, the second return water circulation pump 210 and the third return water circulation pump 310 are respectively the same as the first supply water circulation pump 100, the second supply water circulation pump 200 and the third supply water circulation pump 300. When the flow rates of the supply water circulation pump and the return water circulation pump of the corresponding boilers are kept consistent, it can be ensured that the water level in each boiler remains unchanged.

[0181] S120, controlling the first water supply circulating water pump 100, the second water supply circulating water pump 200 and the third water supply circulating water pump 300 to operate according to the first control flow rate, the second control flow rate and the third control flow rate respectively.

[0182] Exemplarily, the first water supply circulating water pump 100, the first return water circulating water pump 110, the second water supply circulating water pump 200, the second return water circulating water pump 210, the third water supply circulating water pump 300, and the third return water circulating water pump 310 can all adopt variable frequency pumps, and each circulating water pump controls the water pump speed through its own variable frequency controller, thereby adjusting the flow rate.

[0183] S130, after the first real-time power and the second real-time power change, establish an objective function with the goal of minimizing the sum of flow rate changes of the first water supply circulating water pump 100, the second water supply circulating water pump 200 and the third water supply circulating water pump 300.

[0184] The heat added per unit time by the boiler output water relative to the input water is equal to the heating power of the boiler. When the supply and return water temperatures remain unchanged, the temperature difference Δt i The temperature is 60 degrees Celsius, and the specific heat capacity and density of water are known (the specific heat capacity of water is 4.18 × 10^3 J / (kg·°C), and the density of water is 1×10^3kg / m 3 ) These constraints can be expressed as:

[0185]

[0186] S140, solving the objective function to obtain the first regulated flow rate, the second regulated flow rate and the third regulated flow rate of the first water supply circulating water pump 100, the second water supply circulating water pump 200 and the third water supply circulating water pump 300 respectively.

[0187] For example, a genetic algorithm can be used to solve the objective function. When using a genetic algorithm to solve the problem, multiple populations are first generated according to a set step size, each population is a combination of the regulated flow rates of all water supply circulation pumps, and then the populations are sequentially selected, crossed, and mutated, and the population that satisfies the objective function after processing is taken as the optimal population.

[0188] Specifically, the regulated flow in each population will meet all constraints, and the difference between any two regulated flows of the same circulating water pump is a positive integer multiple of the step size. When using the selection process in the genetic algorithm, first calculate the fitness value of each population, which is calculated based on the objective function, and then select a few populations with the largest fitness values ​​to enter the next step of crossover processing. In the crossover process, individuals in two populations will be randomly exchanged to form a new population. In the mutation process, individuals in the population will be modified to a certain extent. After completing a selection, crossover and mutation process in sequence, an iteration is completed. When the number of iterations reaches the set value, the population with the highest fitness value is output as the optimal population.

[0189] After adopting the heritage algorithm, the diversity of the population can be improved as much as possible, the sample space for selecting the optimal population is increased, and the accuracy of the optimal sample is improved.

[0190] S150, controlling the first water supply circulating water pump 100, the second water supply circulating water pump 200 and the third water supply circulating water pump 300 to operate according to the first regulated flow rate, the second regulated flow rate and the third regulated flow rate respectively.

[0191] For example, similar to controlling the flow rate, the purpose of regulating the flow rate of the water supply circulating water pump can be achieved by adjusting the frequency conversion controller of each water supply circulating water pump.

[0192] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

[0193] Embodiment 3, the third embodiment of the present invention, is different from the first two embodiments in that:

[0194] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program codes.

[0195] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0196] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0197] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0198] Example 4, reference Figure 2 , which is an embodiment of the present invention, provides a circulating water pump control system based on real-time power optimization, characterized in that it includes: a data acquisition module, a real-time power calculation module, a control flow determination module, a hierarchical work control module, and an objective function solving module.

[0199] The data acquisition module collects the current and voltage data in the power supply line of the electric boiler in real time, providing basic data for subsequent power calculation.

[0200] The real-time power calculation module calculates the real-time power of the electric boiler based on the collected current and voltage data.

[0201] The control flow determination module determines the control flow of each water supply circulation pump according to the real-time power and the set power to ensure that the heating ratio of each boiler matches the power ratio.

[0202] The stratified operation control module realizes stratified operation control of the water supply circulation pump by adjusting the rotation speed of the water pump to ensure the stable operation of the system.

[0203] The objective function solving module solves the objective function through genetic algorithm, finds the optimal flow adjustment combination, and realizes precise control of the water supply circulation pump.

[0204] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A circulating water pump control method based on real-time power optimization, characterized in that: include, Collecting the real-time power of the first electric boiler and the second electric boiler; Determine the control flow rate according to the set power and the collected real-time power, and control the corresponding water supply circulation pump to work in layers; When the real-time power changes, the objective function is established with the goal of minimizing the sum of the flow changes of the water supply circulation pump, and constraints are set at the same time; Genetic algorithm is used to solve the objective function and obtain the corresponding regulation flow of the water supply circulation pump; According to the obtained regulated flow, the operation of the water supply circulation pump is synchronously regulated; The collecting of the real-time power of the first electric boiler and the second electric boiler includes: connecting a current transformer in series in the power supply line of the electric boiler to measure the current in a non-invasive manner, connecting a voltage sensor in parallel to the power supply line of the electric boiler to measure the voltage, setting a data collector, and transmitting data wirelessly; the data collector reads the current and voltage values ​​at a sampling frequency of once every 30 seconds; Calculate real-time power: real-time power = real-time voltage × real-time current × power factor, where the coal-fired boiler and the first electric boiler and the second electric boiler supply heat at the same time, and the hot water output by the coal-fired boiler, the first electric boiler and the second electric boiler are all supplied to the heat exchanger, and the coal-fired boiler always operates at the set power; The control flow rate is determined by: set , the first real-time power P r1 and the second real-time power P r2 Determine the control flow rates of the first water supply circulating water pump, the second water supply circulating water pump and the third water supply circulating water pump to obtain a first control flow rate, a second control flow rate and a third control flow rate respectively; According to the real-time power of the first electric boiler and the second electric boiler and the set power of the coal-fired boiler, the power proportion of each boiler is calculated: Among them, P1, P2, and P3 represent the power proportions of the coal-fired boiler, the first electric boiler, and the second electric boiler, respectively; Establish the relationship between power and flow. The power of each boiler is proportional to the flow. Use the power ratio as the flow ratio: F1=P1 F2=P2 F3=P3 The final control flow is: Among them, F1, F2, and F3 represent the proportional coefficients of the hot water flow of each boiler, Q 11 , Q 22 , Q 33 They represent the control flow of the coal-fired boiler, the first electric boiler and the second electric boiler, respectively, and Q 总 Indicates the total flow.

2. A circulating water pump control method based on real-time power optimization as claimed in claim 1, characterized in that: The stratified work includes initializing the rotation speeds of the first water supply circulating water pump, the second water supply circulating water pump and the third water supply circulating water pump so that the output flow rate is equal to the calculated control flow rate; Monitor the power of the first electric boiler, the second electric boiler and the coal-fired boiler, as well as the actual flow of the first water supply circulating pump, the second water supply circulating pump and the third water supply circulating pump in real time, compare the actual flow with the calculated control flow, calculate the deviation, and adjust the speed of the water pump according to the deviation; When the power fluctuation of the first electric boiler or the second electric boiler exceeds the set threshold, the power proportion is adjusted according to the fluctuation direction, and the control flow of the water supply circulation pump is adjusted at the same time; When the power fluctuation of the coal-fired boiler exceeds the set threshold, the power proportion is adjusted, and the control flow of the water supply circulation pump is adjusted at the same time; When the system operates in energy-saving mode, the power ratio of the first electric boiler and the second electric boiler is adjusted according to the energy-saving strategy, and the control flow of the water supply circulation pump is adjusted at the same time.

3. A circulating water pump control method based on real-time power optimization as claimed in claim 2, characterized in that: The establishing of the objective function includes establishing the objective function with the goal of minimizing the sum of flow rate changes of the first water supply circulating water pump, the second water supply circulating water pump and the third water supply circulating water pump after the first real-time power and the second real-time power change. Where i is the number of the coal-fired boiler, the first electric boiler and the second electric boiler, i=1, 2, 3 represent the coal-fired boiler, the first electric boiler and the second electric boiler respectively, Q i1 Indicates the control flow of the water supply circulation pump connected to the corresponding boiler, Q i2 Indicates the regulated flow rate of the water supply circulation pump connected to the corresponding boiler; The constraints are: Q i1 ≤Q imax Q i2 ≤Q imax cW i1 ·Δt i =P i1 ,W i1 =ρQ i1 cW i2 ·Δt i =P i2 ,W i2 =ρQ i2 Among them, W 总 Indicates the total flow, Q imax represents the maximum flow rate of the water supply circulation pump connected to the corresponding boiler, c represents the specific heat capacity of water, W i1 Indicates the mass flow rate of the water supply circulating pump connected to the corresponding boiler before adjustment, W i2 Indicates the mass flow rate after adjustment of the water supply circulating pump connected to the corresponding boiler, Δt i Indicates the temperature difference between the boiler input water and output water, P i1 and P i2 They represent the power of the boiler before and after the change respectively, and ρ is the density of water.

4. A circulating water pump control method based on real-time power optimization as claimed in claim 3, characterized in that: The use of a genetic algorithm to solve the objective function includes randomly generating N individuals, each of which contains n=9 genes, representing a combination of regulating flow rates of water supply circulating pumps of three boilers; For each individual, calculate the multi-objective fitness: Among them, F(Q) represents the multi-objective fitness, E(Q) represents the energy consumption function; Use non-dominated sorting to evaluate the Pareto rank of individuals, select based on the Pareto rank and crowding distance of individuals, and maintain the diversity of the population: Among them, P represents the current population, represents the Pareto dominance relationship, and F(Q′) represents the fitness of other individuals Q′; The crossover rate is adjusted by the average fitness and optimal fitness of the current population, and the selected individuals are crossovered to generate new individuals: Among them, r c represents the crossover rate of the current iteration, r c0 represents the initial crossover rate, F avg Represents the average fitness of the current population, F best Indicates the best fitness in the current population; Adjust the mutation step length according to the number of iterations and the maximum number of iterations, and perform mutation operations on the new individuals after crossover: Among them, ΔQ g represents the variable step length of the g-th iteration, ΔQ0 represents the initial step length, G represents the maximum number of iterations, and k represents the parameter that controls the rate at which the step length decreases; Adjust the mutation rate according to the average fitness and the best fitness of the population: Among them, r m Represents the current iteration mutation rate, r m0 represents the initial mutation rate; The newly generated individuals are merged with the original population, and the merged population is selected using non-dominated sorting and crowding distance to form a new generation of population. In each generation, a certain number of elite individuals, that is, individuals with the smallest objective function value in the previous population, are retained and directly enter the next generation to update the optimal population. When the objective function value of an individual in the new population is less than the objective function value of the worst individual in the current optimal population, the worst individual in the optimal population is replaced by the new individual. When the objective function value of the best individual in the new population is less than the objective function value of the best individual in the current optimal population, the optimal population is updated. Assume J is the size of the elite population, P is the current population, and P' is the new population, then: P elite =Black(P∪P′)[:J] Among them, P elite represents the elite population, Sort represents sorting the set, and [:J] represents taking the first J individuals after sorting; Calculate the objective function value of the new population. When the objective function value of the best individual in the new population is less than the optimal population P best The objective function value of the best individual in , then update the optimal population: P best =P best ∪{Q' best }-{Q worst } Among them, Q′ best represents the best individual in the new population, Q worst Represents the individual with the largest objective function value; When the individual in the new population is better than the worst individual in the optimal population, it is replaced; the algorithm stops when one of the following conditions is met: When the preset maximum number of iterations is reached and the objective function value reaches the preset threshold, the algorithm stops and the optimal population P is output. best .

5. A circulating water pump control method based on real-time power optimization as claimed in claim 4, characterized in that: The synchronous regulation of the water supply circulation pump includes defining DFBI as the sum of the ratios of the flow rate changes of each pump monitored in real time to the total flow rate change: Among them, DFBI represents the dynamic flow balance index, ΔQ1, ΔQ2, and ΔQ3 represent the flow changes of three different pumps, and ΔQ 总 It represents the sum of the flow changes of all pumps. When PEBI<0.05, the flow redistribution mechanism is triggered; EEWC is defined as the sum of the ratios of the power change before and after each pump is adjusted to the total power change: Among them, EEWC represents the energy efficiency fluctuation coefficient, ΔP1, ΔP2, and ΔP3 represent the power changes of three different water pumps before and after adjustment, and ΔP 总 It represents the sum of the power changes of all pumps; When EEWC>0.1, the following adjustment strategy is implemented: Calculate the power change rate of each pump P i0 Represents the initial power of pump i, and the one with the largest ΔP′ is adjusted first i pumps; calculate the energy efficiency change rate of each pump Adjust the corresponding water pumps in descending order of energy efficiency change rate, and adjust dynamically according to historical operation data and current working conditions; Calculate the rate of change of temperature difference: Among them, Δt 初期 represents the average input and output water temperature difference under the initial state, Δt i It represents the input and output water temperature difference of the i-th boiler. When TDCR>1.2, the temperature difference compensation adjustment strategy is started; When DFBI<0.05 and EEWC≤0.1, only the water pump flow is adjusted, and other system parameters remain unchanged; when EEWC>0.1 and TDCR≤1.2, the water pump with the best energy efficiency is adjusted first, and the adjustment of other water pumps is considered; when TDCR>1.2, the temperature difference compensation adjustment strategy is started to adjust the working status of all water pumps to ensure stable operation of the system. When multiple adjustment requirements conflict, the priority order is EEWC>DFBI>TDCR.

6. A system using a circulating water pump control method based on real-time power optimization as claimed in any one of claims 1 to 5, characterized in that: It includes data acquisition module, real-time power calculation module, control flow determination module, hierarchical work control module and objective function solution module; The data acquisition module collects the current and voltage data in the power supply line of the electric boiler in real time to provide basic data for subsequent power calculation; The real-time power calculation module calculates the real-time power of the electric boiler based on the collected current and voltage data; The control flow determination module determines the control flow of each water supply circulation pump according to the real-time power and the set power to ensure that the heating ratio of each boiler matches the power ratio; The stratified operation control module realizes stratified operation control of the water supply circulation pump by adjusting the rotation speed of the water pump to ensure the stable operation of the system; The objective function solving module solves the objective function through a genetic algorithm to find the optimal flow rate adjustment combination and realize accurate control of the water supply circulation pump.

7. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 5 are implemented.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

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