Dynamic pressure difference compensation system and adjusting method for heat supply pipe network

Abstract

The invention relates to the technical field of water source heat pump adjustment, and discloses a dynamic pressure difference compensation system and method for a heat supply network, and the method comprises the following steps: obtaining a topological structure and a flow-pressure difference curve of each main pipeline in the heat supply network; establishing a thermal inertia model for each main pipeline; generating a fuzzy rule base of the main pipeline based on the topological structure, the flow-pressure difference curve and a thermal inertia model; determining control parameters of a main pipeline based on the fuzzy rule base; the actual pressure difference and the target pressure difference of the main pipeline are obtained; based on the actual pressure difference, the target pressure difference and the control parameters, the flow adjusting amount of the main pipeline is calculated; adjusting a water pump and a valve of a heat supply pipe network based on the flow adjusting quantity; according to the method, the problem of the heat supply network in the aspect of dynamic pressure difference compensation is solved, and quick response and energy consumption control of pressure difference compensation are both considered.

Description

Technical Field

[0001] This application relates to the technical field of water source heat pump regulation, and specifically to a dynamic differential pressure compensation system and regulation method for a heating pipe network. Background Art

[0002] In a heating pipe network, due to the dynamic changes in heat load (such as the opening and closing of valves at the user end, the start and stop of pumps, etc.), local differential pressure fluctuations in the pipe network will occur. If the differential pressure is unstable, problems such as pipe vibration, equipment wear, and even uneven heating may be caused. Most existing technologies use traditional PID controllers for differential pressure compensation in heating pipe networks, and have poor adaptability to the strong non-linearity and time-variability of heating pipe networks (such as the change of pipe friction with temperature). Traditional heating systems mostly adopt an operation mode of "large flow rate, small temperature difference" to compensate for thermal imbalance, resulting in large pump energy consumption. Moreover, the traditional extensive control strategy of fully opening / closing valves in heating systems further exacerbates energy waste. Existing pipe network differential pressure control systems lack the ability to monitor the operation state of the pipe network in real time and make adaptive adjustments. Although some systems introduce PLC or DCS control, their algorithm flexibility is limited, and it is difficult to achieve multi-objective collaborative optimization, such as the balance between precise differential pressure compensation and minimum energy consumption.

[0003] For example, the patent application with the publication number CN107559942A discloses a method for regulating the heat load of a heating system with double differential pressures, including the following steps: calculating the return water temperature value required for heating according to the outdoor temperature value; collecting the actual supply and return water temperatures of the heat network; comparing the error between the calculated return water temperature and the actual return water temperature, inputting the error signal into a temperature regulator, and the temperature regulator outputs a calculated differential pressure signal for the heat network; using a pressure transmitter to collect the actual supply and return water differential pressure of the heat network, inputting the error signal after comparing the actual differential pressure with the calculated differential pressure signal into a differential pressure regulator, and the differential pressure regulator outputs the frequency signal required by the frequency converter to control the change of the circulating pump speed to achieve double differential pressure operation of the heat network. This application solves the problem of heat load regulation when the flow rate cannot be reduced under the condition of hydraulic imbalance, but still has the problems raised in the background art of this application: poor adaptability to the strong non-linearity and time-variability of the heating pipe network.

[0004] The information disclosed in this background art section is only intended to enhance the overall understanding of this application and should not be regarded as an admission or any form of suggestion that this information constitutes prior art already known to those of ordinary skill in the art. Summary of the Invention

[0005] The technical problem to be solved by this application is to overcome the defects of the prior art, provide a dynamic differential pressure compensation system and regulation method for a heating pipe network, solve the problem of dynamic differential pressure compensation in a heating pipe network, and balance the rapid response of differential pressure compensation and energy consumption control.

[0006] To solve the above technical problems, the present application provides the following technical solutions:

[0007] On the one hand, the present application provides a method for dynamically adjusting the differential pressure of a heat supply pipeline, including the following steps: obtaining the topological structure and flow-differential pressure curve of each main pipeline in the heat supply pipeline; establishing a thermal inertia model for each of the main pipelines;

[0008] Generating a fuzzy rule base for the main pipelines based on the topological structure, flow-differential pressure curve, and thermal inertia model;

[0009] Determining the control parameters of the main pipelines based on the fuzzy rule base;

[0010] Obtaining the actual differential pressure and target differential pressure of the main pipelines; calculating the flow adjustment amount of the main pipelines based on the actual differential pressure, target differential pressure, and control parameters;

[0011] Adjusting the water pumps and valves of the heat supply pipeline based on the flow adjustment amount.

[0012] As a preferred solution of the method for dynamically adjusting the differential pressure of the heat supply pipeline according to the present application, wherein: the method for establishing a thermal inertia model for the main pipelines is as follows:

[0013] Running the heat supply pipeline to a thermal equilibrium state, recording the water temperature in the main pipeline, denoted as T0;

[0014] Setting a monitoring period; continuously monitoring and recording water temperature data within one monitoring period; the water temperature data includes the water temperature at each moment in the main pipeline; denoting the water temperature at the last moment within the monitoring period as T f ;

[0015] Establishing a thermal inertia model and performing fitting of the thermal inertia model based on the water temperature data; the input of the thermal inertia model is any moment, the output is the water temperature in the main pipeline at the corresponding moment, and the model parameters at least include T0, T f and the thermal inertia time constant.

[0016] As a preferred solution of the method for dynamically adjusting the differential pressure of the heat supply pipeline according to the present application, wherein: the method for obtaining the flow-differential pressure curve of the main pipelines is as follows:

[0017] Changing the flow of the main pipeline and collecting differential pressure data of the main pipeline; the differential pressure data includes the differential pressure corresponding to different flows of the main pipeline;

[0018] Constructing a flow-differential pressure equation for the main pipeline; the independent variable of the flow-differential pressure equation is the flow of the main pipeline, and the dependent variable is the differential pressure of the main pipeline;

[0019] Fitting the flow-differential pressure equation based on the differential pressure data to obtain the flow-differential pressure curve.

[0020] As a preferred solution of the dynamic pressure difference regulation method for the heat supply pipe network described in this application, the method for generating the fuzzy rule base of the main pipeline is as follows:

[0021] Based on the topological structure, obtain the number of branches of the main pipeline; based on the thermal inertia model, extract the thermal inertia time constant of the main pipeline; based on the flow-pressure difference curve, obtain the pressure difference slope of the main pipeline;

[0022] Generate a fuzzy rule base for the main pipeline based on the number of branches, thermal inertia time constant, and pressure difference slope of the main pipeline; specifically including:

[0023] Set m fuzzy sets for the number of branches, thermal inertia time constant, and pressure difference slope respectively; set an increment interval for each type of PID coefficient; where, the PID coefficients include the proportional coefficient K p , integral coefficient K i , derivative coefficient K d ;

[0024] Generate fuzzy rules for the main pipeline and form a fuzzy rule base; the input variables of any one of the fuzzy rules include the membership relationship between the number of branches, thermal inertia time constant, pressure difference slope and the fuzzy sets; the output variable of any one of the fuzzy rules includes the increment of each type of PID coefficient; the value range of the increment of any one type of PID coefficient is the increment interval corresponding to the PID coefficient.

[0025] As a preferred solution of the dynamic pressure difference regulation method for the heat supply pipe network described in this application, where: the control parameters include the updated value of each type of PID coefficient; the updated value of any one type of PID coefficient is the sum of the initial value and the increment of the corresponding PID coefficient; the method for determining the control parameters of the main pipeline is as follows:

[0026] Select a membership function; determine the membership relationship between the number of branches, thermal inertia time constant, pressure difference slope and the fuzzy sets through the membership function;

[0027] Based on the membership relationship between the number of branches, thermal inertia time constant, pressure difference slope and the fuzzy sets, query the corresponding fuzzy rule in the fuzzy rule base;

[0028] Based on the corresponding fuzzy rule, determine the increment of each type of PID coefficient;

[0029] Obtain the initial value of each type of PID coefficient; calculate the updated value of each type of PID coefficient based on the initial value and increment of each type of PID coefficient.

[0030] As a preferred solution of the dynamic pressure difference regulation method for the heat supply pipe network described in this application, where: the method for calculating the flow regulation amount of the main pipeline is as follows:

[0031] Continuously collect and record the actual pressure difference of the main pipeline at each moment; denote the actual pressure difference at time t as P(t).

[0032] Obtain the target pressure difference of the main pipeline, and calculate the pressure difference error of the main pipeline at each moment; denote the pressure difference error at time t as e(t); where e(t) is the difference between the actual pressure difference P(t) at time t and the target pressure difference.

[0033] Input the pressure difference error into the PID controller; the PID controller calculates and outputs the flow rate adjustment amount of the main pipeline based on the control parameters.

[0034] As a preferred solution of the dynamic pressure difference adjustment method for the heating pipe network described in this application, wherein: based on the flow rate adjustment amount, the method for adjusting the water pumps and valves of the heating pipe network is as follows:

[0035] Obtain the energy consumption curves of each valve and each water pump for adjusting the flow rate of the main pipeline; obtain the flow contribution curves of each valve and each water pump for adjusting the flow rate of the main pipeline.

[0036] Set constraint conditions based on the flow contribution curves; the constraint conditions include that the sum of the change amounts of the flow contribution values of all water pumps and valves is equal to the flow rate adjustment amount; the change amount of the flow contribution value is the flow contribution value after adjustment of the corresponding water pump or valve minus the flow contribution value before adjustment.

[0037] Set an optimization objective based on the energy consumption curves; the optimization objective is to minimize the total energy consumption of adjusting the water pumps and valves of the heating pipe network.

[0038] Adopt an optimization algorithm to solve the optimization objective under the condition of satisfying the constraint conditions, and obtain the adjustment amounts of each valve and each water pump.

[0039] Adjust the water pumps and valves of the heating pipe network based on the valve opening adjustment amount of each valve and the rotational speed adjustment amount of each water pump.

[0040] As a preferred solution of the dynamic pressure difference adjustment method for the heating pipe network described in this application, wherein: the abscissa of the flow contribution curve of any valve is the valve opening, and the ordinate is the flow contribution value of the corresponding valve; the abscissa of the flow contribution curve of any water pump is the water pump rotational speed, and the ordinate is the flow contribution value of the corresponding water pump; the flow contribution value is the flow value provided by the corresponding valve or water pump for the main pipeline.

[0041] The abscissa of the energy consumption curve of any valve is the adjustment amount of the valve opening, and the ordinate is the energy consumption value of adjusting the valve opening; the abscissa of the energy consumption curve of any water pump is the adjustment amount of the water pump rotational speed, and the ordinate is the energy consumption value of adjusting the water pump rotational speed.

[0042] As a preferred solution of the dynamic differential pressure regulation method for the heat supply pipe network described in this application, the method for setting constraint conditions based on the flow contribution curve is as follows: Obtain the current valve opening of each valve; obtain the current rotational speed of each water pump; set the regulation amount of the valve opening of each valve, and calculate the change amount of the flow contribution value of each valve at the corresponding valve opening regulation amount based on the flow contribution curve of the valve and the current valve opening; set the regulation amount of the rotational speed of each water pump, and calculate the change amount of the flow contribution value of each water pump at the corresponding water pump rotational speed regulation amount based on the flow contribution curve of the water pump and the current rotational speed of the water pump; make the sum of the change amounts of the flow contribution values of all water pumps and valves equal to the flow regulation amount to obtain the constraint condition.

[0043] In a second aspect, this application provides a dynamic differential pressure compensation system for a heat supply pipe network, including a data acquisition module, a modeling module, a regulation strategy module, an optimization module, and a control module; where:

[0044] The data acquisition module is used to collect the differential pressure, flow rate, and water temperature of the main pipeline, as well as the valve opening of each valve and the rotational speed of each water pump; the data acquisition module is also used to obtain the flow contribution curve and energy consumption curve of each water pump and valve;

[0045] The modeling module establishes a thermal inertia model based on the water temperature of the main pipeline, and determines the value of the thermal inertia time constant through data fitting; the modeling module also establishes a flow-differential pressure curve based on the differential pressure and flow rate of the main pipeline, and determines the differential pressure slope;

[0046] The regulation strategy module generates a fuzzy rule base based on the topological structure, flow-differential pressure curve, and thermal inertia model of the main pipeline, and determines the control parameters of the main pipeline based on the fuzzy rule base; the regulation strategy module is also configured with a PID controller, and the PID controller calculates the flow regulation amount of the main pipeline based on the differential pressure error of the main pipeline;

[0047] The optimization module calculates the regulation amounts of the valve opening and the rotational speed of the water pump based on the flow regulation amount;

[0048] The control module generates control instructions for each valve and water pump based on the regulation amount of the valve opening of each valve and the regulation amount of the rotational speed of each water pump, and sends the control instructions to the corresponding valve or water pump.

[0049] Compared with the prior art, the beneficial effects achieved by this application are as follows:

[0050] Through the modeling of the thermal inertia of the heating pipeline, this application eliminates the problem of overshoot or undershoot of the pressure difference caused by thermal hysteresis in traditional PID control. By using the fuzzy rule base to adaptively adjust parameters such as the number of branches and the pressure drop slope, it effectively suppresses the negative impact of network disturbances on the control accuracy and achieves fast and stable pressure difference compensation. Through the multi-device collaborative optimization module, it coordinates the adjustment of the valve opening and the adjustment of the pump speed, dynamically adjusts the matching relationship between the flow rate and the pressure difference, and reduces the energy consumption of the network adjustment. Through dynamic pressure difference compensation, it reduces the risk of pipeline vibration or leakage caused by sudden local pressure changes and improves the safety of the heating network. Description of the Drawings

[0051] In order to more clearly illustrate the technical solutions of the embodiments of this application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings. Among them:

[0052] Figure 1 It is a flowchart of the dynamic pressure difference adjustment method for the heating network provided by this application;

[0053] Figure 2 It is a schematic structural diagram of the dynamic pressure difference compensation system for the heating network provided by this application. Detailed Embodiments

[0054] The following will describe the technical solutions of this application in detail through the drawings and specific embodiments. It should be understood that the embodiments of this application and the specific features in the embodiments are detailed descriptions of the technical solutions of this application, rather than limitations on the technical solutions of this application. Without conflict, the technical features in the embodiments of this application and the embodiments can be combined with each other.

[0055] Embodiment 1

[0056] This embodiment introduces a dynamic pressure difference adjustment method for a heating network. Referring to Figure 1 , the method includes the following steps:

[0057] Obtain the topological structure and flow rate-pressure difference curve of each main pipeline in the heating network; establish a thermal inertia model for each main pipeline;

[0058] The method for establishing a thermal inertia model for the main pipeline is as follows:

[0059] Run the heating network to the thermal equilibrium state, record the water temperature in the main pipeline, denoted as T0; this application preferably uses ±0.5K (the temperature unit is Kelvin) as the fluctuation threshold; when the water temperature in the main pipeline fluctuates within ±0.5K, the heating network reaches the thermal equilibrium state;

[0060] Set a monitoring period; continuously monitor and record the water temperature data within one monitoring period; the water temperature data includes the water temperature at each moment in the main pipeline; denote the water temperature at the last moment in the monitoring period as T f ;

[0061] Establish a thermal inertia model and perform fitting of the thermal inertia model based on the water temperature data; the input of the thermal inertia model is any moment, and the output is the water temperature in the main pipeline at the corresponding moment. The model parameters at least include T0, T f and the thermal inertia time constant. In the embodiments of the present application, a first-order lag model is preferably used as the thermal inertia model, and the equation is as follows:

[0062]

[0063] where j represents any moment; T(j) represents the water temperature in the main pipeline at moment j; T w represents the thermal inertia time constant. The least squares method is used to perform equation fitting through the water temperature data to determine the value of the thermal inertia time constant T w so as to obtain the thermal inertia model.

[0064] The method for obtaining the flow-differential pressure curve of the main pipeline is as follows:

[0065] Change the flow rate of the main pipeline and collect the differential pressure data of the main pipeline; the differential pressure data includes the differential pressure corresponding to different flow rates in the main pipeline; the differential pressure of the main pipeline is the water pressure difference between both ends of the pipeline.

[0066] Construct a flow-differential pressure equation for the main pipeline; the independent variable of the flow-differential pressure equation is the flow rate of the main pipeline, and the dependent variable is the differential pressure of the main pipeline;

[0067] Based on the differential pressure data, fit the flow-differential pressure equation to obtain the flow-differential pressure curve. In this embodiment, a polynomial regression equation is preferably used as the flow-differential pressure equation, and the least squares method is used for equation fitting.

[0068] Generate a fuzzy rule base for the main pipeline based on the topological structure, flow-differential pressure curve, and thermal inertia model; specifically including:

[0069] Based on the topological structure, obtain the number of branches of the main pipeline; based on the thermal inertia model, extract the thermal inertia time constant of the main pipeline; based on the flow-differential pressure curve, obtain the differential pressure slope of the main pipeline; the number of branches is the number of branch pipelines of the main pipeline; the thermal inertia time constant is used to represent the speed of the water temperature change in the main pipeline over time; the differential pressure slope is the slope of the flow-differential pressure curve at the current flow rate;

[0070] Generate a fuzzy rule base for the main pipeline based on the number of branches, thermal inertia time constant, and differential pressure slope of the main pipeline; the method is as follows:

[0071] Set m fuzzy sets for the number of branches, thermal inertia time constant, and differential pressure slope respectively; set an increment interval for each type of PID coefficient; where the PID coefficients include the proportional coefficient K p , integral coefficient K i , and derivative coefficient K d ; In this embodiment, it is preferable to use three fuzzy sets of low, medium, and high as the fuzzy sets for the number of branches, thermal inertia time constant, and differential pressure slope. For example, the fuzzy set of the number of branches includes low, medium, and high. Based on the specific value of the number of branches, the membership relationship between the number of branches and the fuzzy set can be determined; for example, if the number of branches is 5, the number of branches belongs to the fuzzy set "low"; if the number of branches is 20, the number of branches belongs to the fuzzy set "high"; This embodiment also preferably uses [-2, 2] as the increment interval for each type of PID coefficient;

[0072] Generate fuzzy rules for the main pipeline and form a fuzzy rule base; the input variables of any one of the fuzzy rules include the membership relationship between the number of branches, thermal inertia time constant, differential pressure slope and the fuzzy set; the output variables of any one of the fuzzy rules include the increment of each type of PID coefficient, specifically including the increment of the proportional coefficient ΔK p , increment of integral coefficient ΔK i , and increment of derivative coefficient ΔK d ; The value range of the increment of any one type of PID coefficient is the increment interval of the corresponding PID coefficient.

[0073] Based on the fuzzy sets and increment intervals preferred in the embodiments of the present application, the preferred fuzzy rule examples in this embodiment are as follows: If the number of branches belongs to the fuzzy set "low", and the integral coefficient belongs to the fuzzy set "low", and the thermal inertia time constant belongs to the fuzzy set "low", then the increment of the proportional coefficient ΔK p is 1.5, the increment of the integral coefficient ΔK i is 0.5, and the increment of the derivative coefficient ΔK d is -1; If the number of branches belongs to the fuzzy set "high", and the integral coefficient belongs to the fuzzy set "high", and the thermal inertia time constant belongs to the fuzzy set "high", then the increment of the proportional coefficient ΔK p is -1, the increment of the integral coefficient ΔK i is 1.5, and the increment of the derivative coefficient ΔK dis 1. Based on the preferred fuzzy rules of this embodiment, the larger the number of branches, the more inclined to decrease the proportional coefficient, increase the integral coefficient, and increase the differential coefficient to suppress the pressure difference oscillation and quickly eliminate the steady-state error of the pressure difference, thereby solving the problem that the more branches there are in the main pipeline, the more uneven the pressure difference distribution is, and enhancing the anti-interference ability of the heat supply network. Based on the preferred fuzzy rules of this embodiment, the larger the pressure difference slope, the more inclined to decrease the proportional coefficient, decrease the integral coefficient, and increase the differential coefficient to prevent the overshoot of the pressure difference and avoid the accumulation of steady-state errors, thereby adapting to the situation where the pressure difference is more sensitive to the flow rate change and avoiding over-regulation. Based on the preferred fuzzy rules of this embodiment, the larger the thermal inertia time constant, the more inclined to increase the integral coefficient and decrease the differential coefficient to compensate for the heat transfer delay of the heat supply network and suppress the high-frequency oscillation of the pressure difference, thereby adapting to the delay effect of the temperature change in the heat supply network.

[0074] Determine the control parameters of the main pipeline based on the fuzzy rule base; the control parameters include the updated values of each PID coefficient; the updated value of any PID coefficient is the sum of the initial value and the increment of the corresponding PID coefficient;

[0075] The method for determining the control parameters of the main pipeline is as follows:

[0076] Select the membership function; determine the membership relationship between the number of branches, the thermal inertia time constant, the pressure difference slope and the fuzzy set through the membership function; in this embodiment, a triangular membership function is preferably used to calculate the membership degrees of the number of branches, the thermal inertia time constant, and the pressure difference slope to each fuzzy set respectively, so as to determine the membership relationship between the number of branches, the thermal inertia time constant, the pressure difference slope and the fuzzy set.

[0077] Based on the membership relationship between the number of branches, the thermal inertia time constant, the pressure difference slope and the fuzzy set, query the corresponding fuzzy rules in the fuzzy rule base; based on the corresponding fuzzy rules, determine the increment of each PID coefficient;

[0078] Obtain the initial value of each PID coefficient; calculate the updated value of each PID coefficient based on the initial value and the increment of each PID coefficient.

[0079] Obtain the actual pressure difference and the target pressure difference of the main pipeline; calculate the flow regulation amount of the main pipeline based on the actual pressure difference, the target pressure difference, and the control parameters; the method is as follows:

[0080] Continuously collect and record the actual pressure difference of the main pipeline at each moment; record the actual pressure difference at time t as P(t);

[0081] Obtain the target pressure difference of the main pipeline and calculate the pressure difference error at each moment of the main pipeline; record the pressure difference error at time t as e(t); where e(t) is the difference between the actual pressure difference P(t) at time t and the target pressure difference;

[0082] Input the differential pressure error into the PID controller; the PID controller calculates and outputs the flow rate adjustment amount of the main pipeline based on the control parameters. The equation of the PID controller is as follows:

[0083]

[0084] where ΔQ(t) represents the flow rate adjustment amount at time t; K' p represents the updated value of the proportionality coefficient; K i ' represents the updated value of the integral coefficient; K' d represents the updated value of the differential coefficient; e(τ) represents the differential pressure error at time τ; represents the integration of the differential pressure error over time; represents the first-order derivative of the differential pressure error at time t with respect to time.

[0085] Adjust the pumps and valves of the heating pipe network based on the flow rate adjustment amount. The method is as follows:

[0086] Obtain the energy consumption curves of each valve and each pump for adjusting the flow rate of the main pipeline; obtain the flow contribution curves of each valve and each pump for adjusting the flow rate of the main pipeline;

[0087] The abscissa of the flow contribution curve of any valve is the valve opening, and the ordinate is the flow contribution value of the corresponding valve; the abscissa of the flow contribution curve of any pump is the pump speed, and the ordinate is the flow contribution value of the corresponding pump; the flow contribution value is the flow value provided by the corresponding valve or pump for the main pipeline;

[0088] The abscissa of the energy consumption curve of any valve is the adjustment amount of the valve opening, and the ordinate is the energy consumption value for adjusting the valve opening; the abscissa of the energy consumption curve of any pump is the adjustment amount of the pump speed, and the ordinate is the energy consumption value for adjusting the pump speed;

[0089] Through experimental measurement and data fitting, the energy consumption curves of each valve and pump are obtained, and the quantitative relationships between the valve opening adjustment amount, the pump speed adjustment amount and the energy consumption are established, which intuitively reflects the energy consumed under different adjustment amounts of the valve or pump, providing data support for the subsequent optimization goal based on energy consumption. Taking the minimum total energy consumption as the optimization goal enables full consideration of energy consumption factors while adjusting the flow rate, avoiding unnecessary energy consumption. The optimal adjustment scheme found through the optimization algorithm can make the pump and valve operate in a relatively energy-saving state under different working conditions, reducing the operating cost of the heating system and achieving efficient utilization of energy. The flow contribution curve determines the corresponding relationship between the valve opening, the pump speed and the flow rate value they provide for the main pipeline, providing a quantitative means for calculating the flow rate under the constraint conditions. By setting the flow contribution curve and the constraint conditions, each valve and pump can be accurately adjusted according to the required flow rate adjustment amount to ensure that the flow rate of the heating pipe network meets the actual demand, improving the stability and reliability of the heating system and ensuring that heat can be accurately delivered to each user end.

[0090] Set constraint conditions based on the flow contribution curve; the constraint conditions include that the sum of the change amounts of the flow contribution values of all pumps and valves is equal to the flow rate adjustment amount; the change amount of the flow contribution value is the flow contribution value after adjustment of the corresponding pump or valve minus the flow contribution value before adjustment;

[0091] The method for setting constraint conditions based on the flow contribution curve is as follows:

[0092] Obtain the current valve opening of each valve; obtain the current speed of each pump; set the adjustment amount of the valve opening of each valve, and calculate the change amount of the flow contribution value of each valve at the adjustment amount of the corresponding valve opening based on the flow contribution curve of the valve and the current valve opening; set the adjustment amount of the speed of each pump, and calculate the change amount of the flow contribution value of each pump at the adjustment amount of the corresponding pump speed based on the flow contribution curve of the pump and the current speed of the pump; make the sum of the change amounts of the flow contribution values of all pumps and valves equal to the flow rate adjustment amount to obtain the constraint conditions.

[0093] Set an optimization goal based on the energy consumption curve; the optimization goal is to minimize the total energy consumption of the pumps and valves in the heating pipe network; the method for setting the optimization goal based on the energy consumption curve is as follows:

[0094] Calculate the energy consumption value of adjusting each valve at the adjustment amount of the corresponding valve opening based on the energy consumption curve of the valve; calculate the energy consumption value of adjusting each pump at the adjustment amount of the corresponding pump speed based on the energy consumption curve of the pump. Calculate the total energy consumption of adjusting the pumps and valves in the heating pipe network, and take minimizing the total energy consumption as the optimization goal.

[0095] An optimization algorithm is adopted to solve the optimization objective under the condition of satisfying the constraint conditions, and the adjustment amounts of each valve and each water pump are obtained; the optimization algorithm is a linear programming algorithm or a greedy algorithm.

[0096] Based on the valve opening adjustment amount of each valve and the rotational speed adjustment amount of each water pump, the water pumps and valves of the heat supply network are adjusted.

[0097] By the above method, the flow adjustment amount is converted into the adjustment amounts of specific water pumps and valves, and through the constraint conditions, all flow adjustment devices work together, which can ensure that the flow adjustment amount is strictly met and avoid insufficient or excessive network flow. Taking energy consumption as the optimization objective, it is possible to preferentially adjust the devices with lower energy consumption per unit flow (such as high-efficiency pumps or low-resistance valves) and reduce redundant energy consumption. The method described in this embodiment can be extended to heat supply networks of different scales, is compatible with various types of flow adjustment devices, and can adapt to the real-time working conditions of heat supply.

[0098] Embodiment 2

[0099] This embodiment is the second embodiment of the present application; based on the same inventive concept as Embodiment 1, referring to Figure 2 , this embodiment introduces a dynamic differential pressure compensation system for a heat supply network, including a data acquisition module, a modeling module, an adjustment strategy module, an optimization module, and a control module; wherein:

[0100] The data acquisition module is used to collect the differential pressure, flow rate, and water temperature of the main pipeline, as well as the valve opening of each valve and the rotational speed of each water pump; the data acquisition module is also used to obtain the flow contribution curve and energy consumption curve of each water pump and valve;

[0101] The modeling module establishes a thermal inertia model based on the water temperature of the main pipeline and determines the value of the thermal inertia time constant through data fitting; the modeling module also establishes a flow-differential pressure curve based on the differential pressure and flow rate of the main pipeline and determines the differential pressure slope;

[0102] The adjustment strategy module generates a fuzzy rule base based on the topological structure, flow-differential pressure curve, and thermal inertia model of the main pipeline, and determines the control parameters of the main pipeline based on the fuzzy rule base, including determining the updated value of each PID coefficient; the adjustment strategy module is also configured with a PID controller, and the PID controller calculates the flow adjustment amount of the main pipeline based on the differential pressure error of the main pipeline; the adjustment strategy module dynamically matches the network characteristics such as the number of branches, thermal inertia time constant, and differential pressure slope through fuzzy rules, so as to realize the adaptive adjustment of the PID coefficients, overcome the defect that the traditional PID controller is sensitive to parameters, and realize the fast response and anti-interference ability of flow adjustment and differential pressure compensation.

[0103] The optimization module calculates the adjustment amount of the valve opening and the pump speed based on the flow rate adjustment amount; based on the flow contribution curve and the energy consumption curve, the module establishes the constraint conditions for multi-device coordination, and uses an optimization algorithm to find the adjustment scheme of the valve and the pump with the minimum total energy consumption.

[0104] The control module generates control instructions for each valve and pump based on the adjustment amount of the valve opening of each valve and the adjustment amount of the speed of each pump, and sends the control instructions to the corresponding valve or pump; thus, the flow rate adjustment of the main pipeline is completed, and the dynamic compensation of the pressure difference of the heat supply network is realized.

[0105] For the specific function implementation of the above modules, refer to the relevant content in the heat supply network dynamic pressure difference adjustment method described in Embodiment 1, which will not be elaborated here.

[0106] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can be in the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can be in the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0107] The embodiments of the present application have been described above in conjunction with the accompanying drawings. However, the present application is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present application, those of ordinary skill in the art can also make many forms without departing from the purpose and scope of the present application. These all fall within the protection scope of the present application.

Claims

1. A method for dynamically adjusting the differential pressure of a heat supply pipe network, characterized in that: It includes the following steps: Obtain the topological structure and flow-pressure difference curve of each main pipeline in the heat supply pipeline network; establish a thermal inertia model for each of the main pipelines; Generate a fuzzy rule base for the main pipelines based on the topological structure, flow-pressure difference curve, and thermal inertia model; Determine the control parameters of the main pipelines based on the fuzzy rule base; Obtain the actual pressure difference and target pressure difference of the main pipelines; Calculate the flow regulation amount of the main pipelines based on the actual pressure difference, target pressure difference, and control parameters; Adjust the pumps and valves of the heat supply pipeline network based on the flow regulation amount.

2. The dynamic pressure difference adjustment method for a heat supply pipe network according to claim 1, characterized in that: The method for establishing a thermal inertia model for the main pipelines is as follows: Run the heat supply pipeline network to a thermal equilibrium state, record the water temperature in the main pipeline, denoted as T0; Set a monitoring period; continuously monitor and record the water temperature data within a monitoring period; the water temperature data includes the water temperature at each moment in the main pipeline; record the water temperature at the last moment within the monitoring period as T f ; Build a thermal inertia model and fit the thermal inertia model based on the water temperature data; the input of the thermal inertia model is any moment, the output is the water temperature in the main pipeline at the corresponding moment, and the model parameters at least include T0, T f and the thermal inertia time constant.

3. The dynamic pressure difference adjustment method for a heat supply pipe network according to claim 1, characterized in that: The method for obtaining the flow-pressure difference curve of the main pipeline is as follows: Change the flow of the main pipeline and collect the pressure difference data of the main pipeline; the pressure difference data includes the pressure differences corresponding to different flows of the main pipeline; Construct a flow-pressure difference equation for the main pipeline; the independent variable of the flow-pressure difference equation is the flow of the main pipeline, and the dependent variable is the pressure difference of the main pipeline; Fit the flow-pressure difference equation based on the pressure difference data to obtain the flow-pressure difference curve.

4. The dynamic differential pressure regulation method for a heat supply pipe network according to claim 1, wherein: The method for generating a fuzzy rule base for the main pipelines is as follows: Based on the topological structure, obtain the number of branches of the main pipeline; based on the thermal inertia model, extract the thermal inertia time constant of the main pipeline; based on the flow-pressure difference curve, obtain the pressure difference slope of the main pipeline; Generate a fuzzy rule base for the main pipeline based on the number of branches, thermal inertia time constant, and pressure difference slope of the main pipeline; specifically including: Set m fuzzy sets for the number of branches, the thermal inertia time constant, and the pressure difference slope respectively; set an increment interval for each type of PID coefficient; where the PID coefficients include the proportional coefficient K p , the integral coefficient K i , and the derivative coefficient K d ; Generate fuzzy rules for the main pipeline and form a fuzzy rule base; the input variables of any one of the fuzzy rules include the membership relationship between the number of branches, thermal inertia time constant, pressure difference slope, and fuzzy sets; the output variable of any one of the fuzzy rules includes the increment of each PID coefficient; the value range of the increment of any one of the PID coefficients is the increment interval corresponding to the PID coefficient.

5. The dynamic differential pressure regulation method for a heat supply pipe network according to claim 4, characterized in that: The control parameters include the updated values of each PID coefficient; the updated value of any one of the PID coefficients is the sum of the initial value and increment of the corresponding PID coefficient; the method for determining the control parameters of the main pipeline is as follows: Select a membership function; determine the membership relationship between the number of branches, thermal inertia time constant, pressure difference slope, and fuzzy sets through the membership function; Query the corresponding fuzzy rule in the fuzzy rule base based on the membership relationship between the number of branches, thermal inertia time constant, pressure difference slope, and fuzzy sets; Determine the increment of each PID coefficient based on the corresponding fuzzy rule; Obtain the initial value of each PID coefficient; Calculate the updated value of each PID coefficient based on the initial value and increment of each PID coefficient.

6. The dynamic differential pressure regulation method for a heat supply pipe network according to claim 5, characterized in that: The method for calculating the flow regulation amount of the main pipeline is as follows: Continuously collect and record the actual pressure difference of the main pipeline at each moment; denote the actual pressure difference at time t as P(t); Obtain the target pressure difference of the main pipeline and calculate the pressure difference error of the main pipeline at each moment; denote the pressure difference error at time t as e(t); where, e(t) is the difference between the actual pressure difference P(t) at time t and the target pressure difference. Input the differential pressure error into the PID controller; the PID controller calculates and outputs the flow rate adjustment amount of the main pipeline based on the control parameters.

7. The dynamic pressure difference adjustment method for a heat supply pipe network according to claim 6, characterized in that: Based on the flow rate adjustment amount, the method for adjusting the water pumps and valves of the heating pipe network is as follows: Obtain the energy consumption curves of each valve and each water pump for adjusting the flow rate of the main pipeline; obtain the flow contribution curves of each valve and each water pump for adjusting the flow rate of the main pipeline; Set the constraint conditions based on the flow contribution curves; the constraint conditions include that the sum of the change amounts of the flow contribution values of all water pumps and valves is equal to the flow rate adjustment amount; the change amount of the flow contribution value is the flow contribution value after adjustment of the corresponding water pump or valve minus the flow contribution value before adjustment; Set the optimization objective based on the energy consumption curves; the optimization objective is to minimize the total energy consumption of the water pumps and valves for adjusting the heating pipe network; Adopt an optimization algorithm to solve the optimization objective under the condition of satisfying the constraint conditions to obtain the adjustment amounts of each valve and each water pump; Adjust the water pumps and valves of the heating pipe network based on the valve opening adjustment amount of each valve and the rotational speed adjustment amount of each water pump.

8. The dynamic differential pressure regulation method for a heat supply pipe network according to claim 7, characterized in that: The abscissa of the flow contribution curve of any valve is the valve opening, and the ordinate is the flow contribution value of the corresponding valve; the abscissa of the flow contribution curve of any water pump is the rotational speed of the water pump, and the ordinate is the flow contribution value of the corresponding water pump; the flow contribution value is the flow value provided by the corresponding valve or water pump for the main pipeline; The abscissa of the energy consumption curve of any valve is the adjustment amount of the valve opening, and the ordinate is the energy consumption value for adjusting the valve opening; the abscissa of the energy consumption curve of any water pump is the adjustment amount of the rotational speed of the water pump, and the ordinate is the energy consumption value for adjusting the rotational speed of the water pump.

9. The dynamic differential pressure regulation method for a heat supply pipe network according to claim 8, characterized in that: The method for setting the constraint conditions based on the flow contribution curves is as follows: obtain the current valve opening of each valve; obtain the current rotational speed of each water pump; set the adjustment amount of the valve opening of each valve, and calculate the change amount of the flow contribution value of each valve at the adjustment amount of the corresponding valve opening based on the flow contribution curve of the valve and the current valve opening; set the adjustment amount of the rotational speed of each water pump, and calculate the change amount of the flow contribution value of each water pump at the adjustment amount of the corresponding rotational speed of the water pump based on the flow contribution curve of the water pump and the current rotational speed of the water pump; make the sum of the change amounts of the flow contribution values of all water pumps and valves equal to the flow rate adjustment amount to obtain the constraint conditions.

10. A dynamic pressure difference compensation system for a heat supply pipeline network, which is used to implement the dynamic pressure difference adjustment method for a heat supply pipeline network as described in any one of claims 1-9, and is characterized in that: It includes a data acquisition module, a modeling module, an adjustment strategy module, an optimization module, and a control module; where: The data acquisition module is used to collect the differential pressure, flow rate, water temperature of the main pipeline, as well as the valve opening of each valve and the rotational speed of each water pump; the data acquisition module is also used to obtain the flow contribution curves and energy consumption curves of each water pump and valve; The modeling module establishes a thermal inertia model based on the water temperature of the main pipeline, and determines the value of the thermal inertia time constant through data fitting; the modeling module also establishes a flow-differential pressure curve based on the differential pressure and flow rate of the main pipeline, and determines the differential pressure slope; The adjustment strategy module generates a fuzzy rule base based on the topological structure of the main pipeline, the flow-pressure difference curve, and the thermal inertia model, and determines the control parameters of the main pipeline based on the fuzzy rule base; the adjustment strategy module is also configured with a PID controller, and the PID controller calculates the flow adjustment amount of the main pipeline based on the pressure difference error of the main pipeline; The optimization module calculates the adjustment amounts of the valve opening and the pump speed based on the flow adjustment amount; The control module generates control instructions for each valve and pump based on the valve opening adjustment amount of each valve and the speed adjustment amount of each pump, and sends the control instructions to the corresponding valve or pump.

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