Small waste heat power generation control method and system

Abstract

The invention relates to the technical field of waste heat power generation, in particular to a small waste heat power generation control method and system, and the method comprises the steps: obtaining the historical waste heat temperature data of waste heat generation equipment in a waste heat power generation system; the predicted waste heat temperature of the waste heat generation equipment at any time node in a future preset time period is obtained, and an opening degree iteration variable corresponding to the time node is defined; aiming at any opening degree iteration variable at any time node, acquiring a temperature influence coefficient of the predicted waste heat temperature of the waste heat generation equipment aiming at the current temperature of the first-stage heat storage tank, and acquiring a water reserve influence coefficient of the second-stage heat storage tank; constructing a target cost function based on the temperature influence coefficient and the water reserve influence coefficient, and solving to obtain an optimal opening degree iteration variable sequence; and on the basis of the optimal opening iteration variable sequence, a control instruction is generated to control the opening of the valve in the future preset time period. The system has the effect of improving the power generation efficiency and stability of the waste heat power generation system.

Description

Technical Field

[0001] The present application relates to the technical field of waste heat power generation, and in particular to a small-scale waste heat power generation control method and system. Background Art

[0002] In the context of the current growing demand for energy, waste heat power generation technology has received widespread attention as an effective way of energy recovery. Waste heat power generation technology is a technology that uses waste heat or residual heat generated in the industrial production process to generate electricity. This technology can not only improve energy utilization efficiency and reduce energy waste, but also reduce the production costs of enterprises, which is of great significance to environmental protection and sustainable development.

[0003] Conventional waste heat power generation systems have the following technical bottlenecks when dealing with fluctuating waste heat: 1. A single-stage heat storage tank is directly connected to the generator set. When the temperature of the waste heat generated by the waste heat generating equipment drops suddenly, the temperature of the heat storage tank decays rapidly, resulting in a sharp drop in steam production and unstable power generation.

[0004] 2. Independent water level PID control and temperature threshold management are used, but the relationship between the two cannot be optimized in a coordinated manner. For example, excessive water replenishment during low-temperature periods reduces the temperature of the thermal storage tank, forming a vicious cycle of reduced thermal storage tank temperature - reduced power generation efficiency - increased water replenishment - further reduced thermal storage tank temperature; blindly storing heat during high-temperature periods may lead to insufficient water levels and forced interruption of power generation.

[0005] Therefore, conventional waste heat power generation systems have the defects of low power generation efficiency and low power generation stability of the generator set due to unstable waste heat temperature. Summary of the invention

[0006] In order to improve the power generation efficiency and stability of a waste heat power generation system, the present application provides a small-scale waste heat power generation control method and system.

[0007] In the first aspect, the present application provides a small-scale waste heat power generation control method, which adopts the following technical solution: A small-scale waste heat power generation control method, comprising: Acquiring historical waste heat temperature data of a waste heat generating device in a waste heat power generation system, wherein the waste heat power generation system further comprises a primary heat storage tank, at least one secondary heat storage tank and a generator set connected in sequence, and the waste heat generating device is connected to the primary heat storage tank via a control valve; Based on the time series data prediction algorithm and the historical waste heat temperature data, the predicted waste heat temperature of the waste heat generating device at any time node within a future preset time period is obtained, and the opening iteration variable of the control valve corresponding to the time node is defined; In response to the completion of the initialization of the waste heat power generation system, for any opening iteration variable at any time node within a preset time period in the future, the temperature influence coefficient of the predicted waste heat temperature of the waste heat generating device for the current temperature of the primary heat storage tank is obtained, and the predicted water volume of the secondary heat storage tank at the time node is obtained, and the water reserve influence coefficient of the secondary heat storage tank is calculated based on the predicted water volume and the preset standard water volume of the secondary heat storage tank; Based on the temperature influence coefficient and the water reserve influence coefficient, a target cost function is constructed, and a minimum value is solved for the target cost function to obtain an optimal opening iterative variable sequence; Based on the optimal opening iteration variable sequence, a control instruction is generated to adjust the opening of the control valve at any time node within a future preset time period based on the control instruction.

[0008] Optionally, obtaining the temperature influence coefficient of the predicted waste heat temperature of the waste heat generating device with respect to the current temperature of the primary heat storage tank includes: Obtaining a temperature loss coefficient between the waste heat generating device and the primary heat storage tank; Based on the predicted waste heat temperature of the waste heat generating device, the current temperature of the primary heat storage tank and the temperature loss coefficient, a temperature influence coefficient of the predicted waste heat temperature of the waste heat generating device relative to the current temperature of the primary heat storage tank is calculated.

[0009] Optionally, the expression of the temperature influence coefficient is: ; In the formula, for Time node The opening iteration variables, A temperature influence coefficient of the predicted waste heat temperature of the waste heat generating device relative to the current temperature of the primary heat storage tank; is the current temperature of the primary heat storage tank; is the temperature loss coefficient; is the activation function, when When greater than or equal to 0, ,when When it is less than 0, .

[0010] Optionally, obtaining the predicted water volume of the secondary thermal storage tank includes: Obtaining a water volume change value of the first-level heat storage tank between time nodes corresponding to two adjacent opening iteration variables; Based on the water volume change value, the predicted residual water volume of the first-level thermal storage tank at any time point is calculated; It is determined whether the current water volume of the primary heat storage tank is greater than the predicted residual water volume, and the predicted water volume of the secondary heat storage tank is calculated based on the determination result.

[0011] Optionally, the calculating the predicted water volume of the secondary heat storage tank based on the judgment result includes: If the current water volume of the primary heat storage tank is greater than or equal to the predicted residual water volume, determining the predicted water volume of the secondary heat storage tank as the standard water volume of the secondary heat storage tank; If the current water volume of the primary heat storage tank is less than the predicted residual water volume, the predicted water consumption of the secondary heat storage tank itself is predicted, and the predicted water volume of the secondary heat storage tank is calculated based on the standard water volume of the secondary heat storage tank and the predicted water consumption itself.

[0012] Optionally, the predicting of the water consumption of the secondary thermal storage tank itself includes: Obtain the average water flow rate of the regulating valve between the primary heat storage tank and any secondary heat storage tank; Based on the average water flow, the overall predicted water consumption of the secondary thermal storage tank at any time node is calculated; Obtaining a target time node at which the current water volume of the first-level heat storage tank is less than the predicted residual water volume, and calculating the consumption time of the second-level heat storage tank consuming its own water volume based on the target time node and the time node; Based on the consumption time and the overall predicted water consumption, the predicted water consumption of the secondary thermal storage tank itself is calculated.

[0013] Optionally, the expression for predicting the residual water volume of the primary heat storage tank at any time node is: ; In the formula, For The predicted residual water volume in the primary thermal storage tank at the time node; for The time node corresponding to The number of iteration steps before the opening iteration variable; The water volume change value of the first-level thermal storage tank for each iteration step; For the The opening iteration variable corresponds to The superposition value of all water inflows before the time node, the water inflow is calculated by the opening of the control valve and the valve information of the control valve.

[0014] Optionally, the expression of the water reserve influence coefficient of the secondary thermal storage tank is: ; ; In the formula, for The time node corresponds to Water reserve influence coefficient of each secondary thermal storage tank; For The time node corresponds to The predicted water volume of each secondary thermal storage tank; For the Standard water volume of each secondary thermal storage tank; for The minimum value of the water reserve influence coefficient of all secondary thermal storage tanks corresponding to the time node is selected As in The water reserve influence coefficient of all the secondary thermal storage tanks at the time node.

[0015] Optionally, the expression of the target cost function is: ; In the formula, is the total number of opening iteration variables; for Temperature influence coefficient at time node; is the water volume warning line parameter; for Water reserve impact coefficient corresponding to the time node; is the activation function, when When greater than 0, = ,when When it is less than or equal to 0, =0.

[0016] In the second aspect, the present application provides a small waste heat power generation control system, which adopts the following technical solution: A small waste heat power generation control system comprises: a processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, the small waste heat power generation control method described above is implemented.

[0017] The beneficial effect is that the above-mentioned small-scale waste heat power generation control method is generated into a computer program and stored in a memory so as to be loaded and executed by a processor, thereby making a system based on the memory and the processor for easy use.

[0018] Technical effects of this application: 1. Set up two-stage heat storage tanks, and use the first-stage heat storage tank to buffer the preheating temperature output by the waste heat generating equipment, reduce the risk of sudden temperature drop in the second-stage heat storage tank, and improve the power generation stability of the waste heat power generation system.

[0019] 2. By obtaining the historical waste heat temperature data of the waste heat generating equipment, predicting the predicted waste heat temperature in the future preset time period, predicting the waste heat output fluctuation of the waste heat generating equipment, improving the waste heat utilization rate and reducing energy waste.

[0020] 3. Calculate the temperature influence coefficient and the water reserve influence coefficient, construct the target cost function through the temperature influence coefficient and the water reserve influence coefficient, and solve the optimal opening iterative variable sequence, so as to adjust the opening of the control valve in real time according to the optimal opening iterative variable sequence, which helps to reduce power generation fluctuations, improve the operating efficiency, stability and automation level of the waste heat power generation system, and at the same time reduce energy consumption and maintenance costs, and achieve energy conservation and emission reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] By reading the detailed description below with reference to the accompanying drawings, the above and other purposes, features and advantages of the exemplary embodiments of the present application will become easily understood. In the accompanying drawings, several embodiments of the present application are shown in an exemplary and non-restrictive manner, and the same or corresponding numbers represent the same or corresponding parts.

[0022] Figure 1 Schematic diagram of the small waste heat power generation system of this embodiment.

[0023] Figure 2 It is a schematic diagram of the overall process of a small-scale waste heat power generation control method in this embodiment.

[0024] Figure 3 It is a flow chart of steps S201 - S202 in a small-scale waste heat power generation control method of this embodiment.

[0025] Figure 4 It is a flowchart of steps S301-S303 in a small-scale waste heat power generation control method of this embodiment.

[0026] Figure 5 It is a flowchart diagram of steps S401-S404 in a small-scale waste heat power generation control method of this embodiment. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0028] It should be understood that when the terms "first", "second", etc. are used in the claims, specification and drawings of the present application, they are only used to distinguish different objects, rather than to describe a specific order. The terms "include" and "comprise" used in the specification and claims of the present application indicate the presence of the described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their collections.

[0029] The present embodiment discloses a small-scale waste heat power generation control method, which is applied to a small-scale waste heat power generation system. In a conventional waste heat power generation system, a single-stage heat storage tank is usually directly connected to a generator set. However, due to the working state of the waste heat generating device, the waste heat temperature output by the waste heat generating device is not stable, resulting in the temperature of the heat storage tank fluctuating with the waste heat temperature of the waste heat generating device, further resulting in unstable power generation of the generator set.

[0030] Reference Figure 1 , is a schematic diagram of a small waste heat power generation system in this embodiment. The small waste heat power generation system in this embodiment includes a waste heat generating device, a primary heat storage tank, at least one secondary heat storage tank and a generator set corresponding to the secondary heat storage tank, which are connected in sequence. Among them, the waste heat generating device is connected to the primary heat storage tank through a control valve, the primary heat storage tank is connected to the secondary heat storage tank through an adjusting valve, and the secondary heat storage tank is connected to the generator set to provide stable steam for the generator set. In this embodiment, a two-stage heat storage tank is provided, in which the primary heat storage tank serves as a heat buffer tank and the secondary heat storage tank serves as a steam output tank, which can effectively cope with the waste heat temperature fluctuation of the waste heat generating device and improve the temperature stability of the heat storage tank.

[0031] In a small waste heat power generation system, there is a relationship between the secondary heat storage tank and the generator set: the higher the temperature, the greater the power generation. This is because when the volume of the heat storage tank is constant, the higher the temperature, the greater the amount of steam, and the corresponding power generation of the generator set. In order to improve power generation efficiency, it is necessary to ensure that the temperature of the secondary heat storage tank is as high as possible. At the same time, the higher temperature of the secondary heat storage tank leads to a large water consumption. Therefore, the opening of the regulating valve between the primary heat storage tank and the secondary heat storage tank should be controlled to keep the water level of the secondary heat storage tank stable, which requires the primary heat storage tank to have sufficient water storage capacity. Since the primary heat storage tank and the secondary heat storage tank are connected, if the temperature of the secondary heat storage tank needs to be as high as possible, the temperature of the primary heat storage tank should also be as high as possible.

[0032] Based on this, affected by the working state of the waste heat generating device, the waste heat temperature output by the waste heat generating device is unstable. In this embodiment, the waste heat temperature of the waste heat generating device is predicted so that when the waste heat temperature is high, the control valve has a larger valve opening to ensure that the temperature of the primary heat storage tank is as high as possible; when the waste heat temperature is low, the control valve has a smaller valve opening to reduce the possibility of a sudden drop in temperature in the primary heat storage tank. At the same time, when the waste heat temperature is low, it is necessary to ensure that the water storage capacity in the primary heat storage tank is sufficient for the water consumption of the secondary heat storage tank.

[0033] Therefore, in the small waste heat power generation system of this embodiment, the core valve is the control valve between the waste heat generating device and the primary heat storage tank, and the control valve determines the temperature and water storage capacity of the subsequent secondary heat storage tank. That is, the main scheme of this embodiment is to dynamically adjust the opening of the control valve to cope with the waste heat temperature fluctuations of the waste heat generating device and provide sufficient water in the secondary heat storage tank.

[0034] The following describes a waste heat power generation control method of a waste heat power generation system.

[0035] For the waste heat power generation system in this embodiment, refer to Figure 2 , is a schematic diagram of the overall flow of the waste heat power generation control method in this embodiment, and the control method includes: S101, obtaining historical waste heat temperature data of a waste heat generating device in a waste heat power generation system, wherein the waste heat power generation system further comprises a primary heat storage tank, at least one secondary heat storage tank and a generator set connected in sequence, and the waste heat generating device is connected to the primary heat storage tank via a control valve; S102, based on the time series data prediction algorithm and the historical waste heat temperature data, obtain the predicted waste heat temperature of the waste heat generating equipment at any time node in the future preset time period, and define the opening iteration variable corresponding to the control valve and the time node; S103, in response to the completion of the initialization of the waste heat power generation system, for any opening iteration variable at any time node in a future preset time period, obtaining a temperature influence coefficient of the predicted waste heat temperature of the waste heat generating device for the current temperature of the primary heat storage tank; S104, obtaining the predicted water volume of the secondary heat storage tank at the time node, and calculating the water reserve influence coefficient of the secondary heat storage tank based on the predicted water volume and the preset standard water volume of the secondary heat storage tank; S105, constructing a target cost function based on the temperature influence coefficient and the water reserve influence coefficient, solving the target cost function for the minimum value, and obtaining an optimal opening iteration variable sequence; S106: Generate a control instruction based on the optimal opening iteration variable sequence, so as to adjust the opening of the control valve at any time node within a future preset time period based on the control instruction.

[0036] In step S101, the waste heat temperature of the waste heat generating equipment is predicted, and the historical waste heat temperature data of the waste heat generating equipment needs to be obtained. A temperature sensor can be installed in the waste heat generating equipment, and the collection time can be set. For example, the waste heat temperature is collected every 5 minutes, and the waste heat temperature for 3 days is obtained as the historical waste heat temperature data. In other embodiments, other specific times can be selected.

[0037] In step S102, this embodiment uses a time series data prediction algorithm to predict the waste heat temperature of the waste heat generating equipment, for example, by obtaining 3 days of historical waste heat temperature data to predict the predicted waste heat temperature within the next hour.

[0038] Specifically, the time series data prediction algorithm can adopt any one of the methods such as ARIMA (autoregressive integrated moving average model), LSTM (Long Short-Term Memory, long short-term memory neural network), least squares fitting, STL (time series decomposition), etc., which will not be repeated in this embodiment. Through the time series data prediction algorithm and the historical waste heat temperature data, the predicted waste heat temperature within the future preset time period is predicted and obtained, and the predicted waste heat temperature is the same as the collection frequency of the temperature sensor.

[0039] Furthermore, the predicted residual heat temperature is interpolated by the least square method to obtain the predicted residual heat temperature at any time node in the future preset time period. For example, the preset time period is 1 hour, and the adjacent time nodes are separated by 1 second, so the predicted residual heat temperature corresponding to every 1 second in the next 1 hour can be obtained. In other embodiments, other specific times can be selected.

[0040] For any time node in a preset time period in the future, this embodiment defines the opening iteration variable of the control valve at that time point, which represents the opening value of the control valve corresponding to any time node. There is an iteration step between each two adjacent opening iteration variables. For example, at the 52nd second of the next hour, the opening value of the control valve is 0.21, i.e., 21%. The purpose of this embodiment is to solve the optimal opening iteration variable sequence composed of the optimal opening iteration variables corresponding to each time node, so as to control the opening of the control valve in seconds in the future time period based on the optimal opening iteration variable sequence, so as to achieve long-term and stable operation of the waste heat power generation system.

[0041] In step S103, the waste heat power generation system needs to be initialized first. In this embodiment, after the waste heat power generation system is initialized, the water storage capacity of the first-level heat storage tank and the second-level heat storage tank reaches the standard water volume, and the temperature is kept as high as possible.

[0042] Specifically, the control valve between the waste heat generating device and the first-level heat storage tank is controlled to ensure that the first-level heat storage tank obtains water with a sufficient temperature. When the waste heat power generation system is initialized, if it is detected that the waste heat temperature of the waste heat generating device is lower than the preset temperature value, the control valve is closed to reduce the possibility of temperature reduction in the first-level heat storage tank and the second-level heat storage tank; if it is detected that the waste heat temperature of the waste heat generating device is greater than or equal to the preset temperature value, the control valve and the regulating valve are opened until the standard water level of the first-level heat storage tank and the second-level heat storage tank, at which time the temperature in the first-level heat storage tank and the second-level heat storage tank is higher than the preset temperature value, and the initialization of the small waste heat power generation system is completed. For example, the preset temperature value is 70°C, and other temperatures can also be selected in other embodiments.

[0043] After completing the initialization of the small waste heat power generation system, the waste heat power generation process can be started. Since the water storage capacity of the secondary heat storage tank is affected by the water storage capacity of the primary heat storage tank, the main function of the primary heat storage tank compared to the secondary heat storage tank is to ensure the stability of the water storage capacity of the secondary heat storage tank. In this embodiment, a conventional control method is selected to control the regulating valve between the primary heat storage tank and the secondary heat storage tank so that the water storage capacity of the secondary heat storage tank is as consistent as possible with the standard water volume. Conventional control methods can adopt methods such as PID control or fuzzy control. Such control methods are existing technologies and will not be repeated in this embodiment.

[0044] This embodiment realizes dynamic regulation of the temperature and water storage capacity of the heat storage tank by adjusting the opening of the control valve, thereby improving power generation efficiency and stability. The temperature of the heat storage tank is mainly affected by the waste heat temperature of the waste heat generating device, and the water storage capacity mainly refers to the water storage capacity of the secondary heat storage tank. Therefore, this embodiment introduces the temperature influence coefficient of the predicted waste heat temperature of the waste heat generating device for the current temperature of the primary heat storage tank and the water reserve influence coefficient of the secondary heat storage tank. These two parameters are used to construct the target cost function.

[0045] Among them, the predicted waste heat temperature of the waste heat generating equipment is the temperature influence coefficient of the current temperature of the first-level heat storage tank. The predicted waste heat temperature is continuous data within a preset time period in the future. Therefore, the predicted waste heat temperature may include high and low temperatures. From the above analysis, it can be seen that when the waste heat temperature of the waste heat generating equipment is high, the control valve should be at a larger opening. At this time, the temperature influence coefficient is defined as 0. When the waste heat temperature is low, it means that it will have a greater impact on the temperature of the first-level heat storage tank, which may cause the temperature to drop. The lower the waste heat temperature, the more obvious the impact, resulting in a drop in the temperature of the second-level heat storage tank, and ultimately reducing the power generation. Therefore, the lower the waste heat temperature is defined, the greater the temperature influence coefficient. The high and low waste heat temperature here is determined by the preset temperature value.

[0046] It is worth mentioning that in the present embodiment, when the waste heat temperature is greater than or equal to the preset temperature value, the control valve and the regulating valve both maintain their own water storage capacity at the standard water volume through conventional control methods, such as PID control or fuzzy control, and when the waste heat temperature is lower than the preset temperature value, the opening optimization method for the control valve is used to adjust and control the opening of the control valve.

[0047] Specifically, refer to Figure 3 , obtain the temperature influence coefficient of the predicted waste heat temperature of the waste heat generating device for the current temperature of the primary heat storage tank, including: S201, obtaining a temperature loss coefficient between the waste heat generating device and the primary heat storage tank; S202. Based on the predicted waste heat temperature of the waste heat generating device, the current temperature of the primary heat storage tank and the temperature loss coefficient, calculate the temperature influence coefficient of the predicted waste heat temperature of the waste heat generating device relative to the current temperature of the primary heat storage tank.

[0048] After the waste heat temperature of the waste heat generating device is heat exchanged with water, the heated water is input into the primary heat storage tank, and the hot water received by the primary heat storage tank is stored as a heat storage medium or input into the secondary heat storage tank. When the waste heat temperature is heat exchanged and the hot water is transmitted, temperature loss will occur. Therefore, this embodiment introduces the temperature loss coefficient between the waste heat generating device and the primary heat storage tank, and comprehensively calculates the temperature influence coefficient in combination with the predicted waste heat temperature and the current temperature of the primary heat storage tank.

[0049] The expression of the temperature influence coefficient in this embodiment is: ; In the formula, for the time node No. The opening iteration variables, The temperature influence coefficient of the predicted waste heat temperature of the waste heat generating device relative to the current temperature of the primary heat storage tank; is the current temperature of the first-stage thermal storage tank; is the temperature loss coefficient; is the activation function, when When greater than or equal to 0, ,when When it is less than 0, .when When it is less than 0, it means that the temperature influence coefficient should be retained, and The smaller the value, the The bigger.

[0050] in, is the temperature loss coefficient between the waste heat temperature and the first-stage heat storage tank. A temperature loss function curve can be used, or a constant can be selected according to the actual situation. For example, =-2.

[0051] In step S104, when the waste heat temperature of the waste heat generating equipment is lower than the preset temperature value, the control valve should be maintained at a relatively small opening. In order to maintain the standard water volume of the secondary heat storage tank, the water in the primary heat storage tank needs to be consumed. Therefore, the predicted remaining water volume of the secondary heat storage tank is calculated by the change in the water volume of the primary heat storage tank, and the water reserve influence coefficient is further calculated.

[0052] Reference Figure 4 , according to the water volume change value of the first-level thermal storage tank, the predicted water volume of the second-level thermal storage tank is obtained, including: S301, obtaining a water volume change value of a primary heat storage tank between time nodes corresponding to two adjacent opening iteration variables; S302, based on the water volume change value, calculate the predicted residual water volume of the primary thermal storage tank at any time point; S303: Determine whether the current water volume of the primary heat storage tank is greater than the predicted residual water volume, and calculate the predicted water volume of the secondary heat storage tank based on the determination result.

[0053] Specifically, a water level sensor disposed in the primary heat storage tank is used to measure the water level change value of the primary heat storage tank between time nodes corresponding to two adjacent opening iteration variables (i.e., one iteration step), and the water volume change value of the primary heat storage tank is calculated through the water level change value.

[0054] After the system is started, the predicted residual water volume in the primary heat storage tank at any startup time node is calculated based on the water volume change value, that is, the predicted residual water volume can be obtained by subtracting the water volume change value from the standard water volume of the primary heat storage tank.

[0055] The expression for the predicted residual water volume of the primary thermal storage tank at any time point is: ; In the formula, For The predicted residual water volume in the primary thermal storage tank at the time node; for The time node corresponding to The number of iteration steps before the opening iteration variable; The change in water volume in the first-level thermal storage tank for each iteration step; For the The opening iteration variable corresponds to The superposition value of all water inflows before the time node. The water inflow is calculated by controlling the valve opening and the valve information of the control valve. For example, if the total iteration step is =10, in calculating the =5 steps, =4, indicating that the actions in the first 4 iterations have been completed.

[0056] Further, it is determined whether the current water volume of the primary heat storage tank is greater than the predicted residual water volume, and the predicted water volume of the secondary heat storage tank is calculated according to the determination result.

[0057] Specifically, if the current water volume of the primary heat storage tank is greater than or equal to the predicted residual water volume, the predicted water volume of the secondary heat storage tank is determined to be the standard water volume of the secondary heat storage tank, that is, if the current water volume is greater than or equal to the predicted residual water volume, it means that the water storage volume of the primary heat storage tank is sufficient and the secondary heat storage tank does not need to consume its own water storage.

[0058] If the current water volume of the primary heat storage tank is less than the predicted residual water volume, the predicted water consumption of the secondary heat storage tank is predicted. The predicted water volume of the secondary heat storage tank is calculated based on the standard water volume and the predicted water consumption of the secondary heat storage tank. That is, if the current water volume of the primary heat storage tank is less than the predicted residual water volume, it means that the water storage volume of the primary heat storage tank is insufficient, and the secondary water storage tank starts to use its own water storage.

[0059] Reference Figure 5 , predict the water consumption of the secondary thermal storage tank, including: S401, obtaining an average water flow rate of a regulating valve between a primary heat storage tank and any secondary heat storage tank; S402, based on the average water flow, calculate the overall predicted water consumption of the secondary thermal storage tank at any time point; S403, obtaining a target time node at which the current water volume of the first-level thermal storage tank is less than the predicted residual water volume, and calculating the consumption time of the second-level thermal storage tank consuming its own water volume based on the target time node; S404: Based on the consumption time and the overall predicted water consumption, the predicted water consumption of the secondary heat storage tank itself is calculated.

[0060] Specifically, the average water flow rate of the regulating valve between the primary thermal storage tank and any secondary thermal storage tank is obtained, and the ratio of the average water flow rate of one secondary thermal storage tank to the average water flow rate of the regulating valves of the remaining secondary thermal storage tanks is calculated based on the average water flow rate, and the ratio is multiplied by the water volume change value of the primary thermal storage tank to obtain the overall predicted water consumption of the secondary thermal storage tank at the startup time node. The water flow rate can be calculated by adjusting the opening of the valve and the valve information, which will not be described in detail in this embodiment.

[0061] When the current water volume of the first-level thermal storage tank is less than the predicted residual water volume, the time node is obtained as the target time node, and the consumption time of the second-level thermal storage tank consuming its own water volume is calculated based on the target time node and the start time node. For example, the current start time node is the 10th second, and the target time node when the current water volume of the first-level thermal storage tank is less than the predicted residual water volume is the 8th second, then the consumption time of the second-level thermal storage tank consuming its own water volume is determined to be 10-8=2 seconds. At this time, the predicted water consumption of the second-level thermal storage tank can be obtained by multiplying the water volume change value / target time node by the consumption time. For example, if the water volume change value of the first-level thermal storage tank is 24m³, then the predicted water consumption of the second-level thermal storage tank is (24 / 8)×2=6m³.

[0062] After obtaining the predicted water consumption of the secondary heat storage tank itself, the predicted water volume of the secondary heat storage tank can be calculated by subtracting the predicted water consumption of the secondary heat storage tank itself from the standard water volume of the secondary heat storage tank.

[0063] In this embodiment, the expression of the water reserve influence coefficient of the secondary thermal storage tank is: ; ; In the formula, for The time node corresponds to Water reserve influence coefficient of each secondary thermal storage tank; For The time node corresponds to The predicted water volume of each secondary thermal storage tank; For the Standard water volume of each secondary thermal storage tank; for The minimum value of the water reserve influence coefficient of all secondary thermal storage tanks corresponding to the time node is selected As in The water reserve influence coefficient of all the secondary thermal storage tanks at the time node.

[0064] In step S105, after constructing the expressions of the temperature influence coefficient and the water reserve influence coefficient, a target cost function is constructed according to the expressions of the temperature influence coefficient and the water reserve influence coefficient, and the target cost function is solved for the minimum value to obtain the optimal opening iterative variable sequence.

[0065] Specifically, the expression of the target cost function constructed in this embodiment is: ; In the formula, is the total number of opening iteration variables; for Temperature influence coefficient at time node; is the water volume warning line parameter; for Water reserve impact coefficient corresponding to the time node; is the activation function, when When greater than 0, = ,when When it is less than or equal to 0, =0.

[0066] Target cost function The core requirement is to minimize the impact of waste heat temperature fluctuations on the primary thermal storage tank during long-term operation, while reducing the possibility of water shortage in the secondary thermal storage tank. The larger the temperature impact coefficient, the more severe the temperature impact of low-temperature waste heat on the primary thermal storage tank, and the smaller the water reserve impact coefficient, the more water shortage in the secondary thermal storage tank.

[0067] The target cost function Logical explanation: When the residual heat temperature is greater than or equal to the preset temperature value, =0, no matter how, = 0. At this time, the opening optimization algorithm of the control valve is closed, and control methods such as PID control or fuzzy control are directly used to maximize the water inflow of the first-stage heat storage tank, giving priority to increasing the temperature of the heat storage tank.

[0068] When the residual heat temperature is lower than the preset temperature value, >0, At this time, if the water storage capacity of the secondary heat storage tank is sufficient, Only by Weak drive, the valve opening is close to 0 (to reduce the mixing of cold water); if the water storage capacity of the secondary heat storage tank is insufficient, and The smaller the punishment, the heavier the penalty. The temperature increases significantly, and the optimization algorithm is forced to increase the opening of the control valve to replenish water. That is, when the temperature is high, the fluctuation of the water storage capacity is ignored and the heat is stored with all efforts. When the temperature is low, the water storage capacity is the first priority to avoid power generation interruption.

[0069] in, The preferred setting is in the range of 0.85 to 0.95. For example, =0.9, which means that a 10% water level buffer is reserved for the secondary heat storage tank to prevent transient fluctuations from triggering false alarms.

[0070] Based on the target cost function, the dynamic programming or gradient descent algorithm is used to solve the minimum value of the target cost function to obtain the optimal opening iteration variable for each time node in the future time period, and all the optimal opening iteration variables are sequentially constructed into an optimal opening iteration variable sequence, for example, the first moment is 0.20, the second moment is 0.25, the third moment is 0.30, the fourth moment is 0.35, the fifth moment is 0.31, the sixth moment is 0.25...

[0071] Step S106, generating a control instruction for the control valve based on the optimal opening iteration variable sequence. If, in the previous steps, the waste heat temperature is not interpolated or does not reach the second level after interpolation, in this step, the optimal opening iteration variable sequence can also be interpolated by an interpolation algorithm to generate a second-level control instruction, such as a cubic spline interpolation algorithm, so as to dynamically adjust the opening of the control valve at any time node in a preset time period in the future through the control instruction.

[0072] An example of the control effect of a small-scale waste heat power generation control method of this embodiment is shown in Table 1 (the water storage capacity in the table is the water storage capacity of the secondary heat storage tank): Table 1 Example of control effect of a small waste heat power generation control method

[0073] The embodiment of the present application sets up a two-stage heat storage tank, and uses the first-stage heat storage tank to buffer the preheating temperature output by the waste heat generating device, thereby reducing the risk of sudden temperature drop in the second-stage heat storage tank and improving the power generation stability of the waste heat power generation system. By obtaining the historical waste heat temperature data of the waste heat generating device, the predicted waste heat temperature in the future preset time period is predicted, and the waste heat output fluctuation of the waste heat generating device is predicted, thereby improving the waste heat utilization rate and reducing energy waste. The target cost function is constructed through the temperature influence coefficient and the water reserve influence coefficient, and the optimal opening iterative variable sequence is solved, so as to adjust the opening of the control valve in real time according to the optimal opening iterative variable sequence, which helps to reduce power generation fluctuations, improve the operating efficiency, stability and automation of the waste heat power generation system, and at the same time reduce energy consumption and maintenance costs, so as to achieve energy conservation and emission reduction.

[0074] An embodiment of the present application also discloses a small waste heat power generation control system, including a processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, a small waste heat power generation control method according to the present application is implemented.

[0075] The above system also includes other components well known to those skilled in the art, such as a communication bus and a communication interface, and their configuration and functions are known in the art, so they will not be described in detail here.

[0076] In the present application, the aforementioned memory may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, apparatus, or device. For example, a computer-readable storage medium may be any appropriate magnetic storage medium or magneto-optical storage medium, such as a resistive random access memory RRAM (Resistive Random Access Memory), a dynamic random access memory DRAM (Dynamic Random Access Memory), a static random access memory SRAM (Static Random Access Memory), an enhanced dynamic random access memory EDRAM (Enhanced Dynamic Random Access Memory), a high bandwidth memory HBM (High Bandwidth Memory), a hybrid memory cube HMC (Hybrid Memory Cube), etc., or any other medium that can be used to store the required information and can be accessed by an application, a module, or both. Any such computer storage medium may be part of a device or accessible or connectable to a device.

[0077] Although this specification has shown and described a plurality of embodiments of the present application, it is obvious to those skilled in the art that such embodiments are provided by way of example only. Those skilled in the art will think of many changes, modifications and alternatives without departing from the thought and spirit of the present application. It should be understood that in the process of practicing the present application, various alternatives to the embodiments of the present application described herein may be adopted.

[0078] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A small-scale waste heat power generation control method, characterized in that: include: Acquiring historical waste heat temperature data of a waste heat generating device in a waste heat power generation system, wherein the waste heat power generation system further comprises a primary heat storage tank, at least one secondary heat storage tank and a generator set connected in sequence, and the waste heat generating device is connected to the primary heat storage tank via a control valve; Based on the time series data prediction algorithm and the historical waste heat temperature data, the predicted waste heat temperature of the waste heat generating device at any time node within a future preset time period is obtained, and the opening iteration variable of the control valve corresponding to the time node is defined; In response to the completion of the initialization of the waste heat power generation system, for any opening iteration variable at any time node within a preset time period in the future, the temperature influence coefficient of the predicted waste heat temperature of the waste heat generating device for the current temperature of the primary heat storage tank is obtained, and the predicted water volume of the secondary heat storage tank at the time node is obtained, and the water reserve influence coefficient of the secondary heat storage tank is calculated based on the predicted water volume and the preset standard water volume of the secondary heat storage tank; Based on the temperature influence coefficient and the water reserve influence coefficient, a target cost function is constructed, and a minimum value is solved for the target cost function to obtain an optimal opening iterative variable sequence; Based on the optimal opening iteration variable sequence, a control instruction is generated to adjust the opening of the control valve at any time node within a future preset time period based on the control instruction.

2. A small-scale waste heat power generation control method according to claim 1, characterized in that: The step of obtaining the temperature influence coefficient of the predicted waste heat temperature of the waste heat generating device relative to the current temperature of the primary heat storage tank includes: Obtaining a temperature loss coefficient between the waste heat generating device and the primary heat storage tank; Based on the predicted waste heat temperature of the waste heat generating device, the current temperature of the primary heat storage tank and the temperature loss coefficient, a temperature influence coefficient of the predicted waste heat temperature of the waste heat generating device relative to the current temperature of the primary heat storage tank is calculated.

3. A small-scale waste heat power generation control method according to claim 2, characterized in that: The expression of the temperature influence coefficient is: ； In the formula, for Time node The opening iteration variables, A temperature influence coefficient of the predicted waste heat temperature of the waste heat generating device relative to the current temperature of the primary heat storage tank; is the current temperature of the primary heat storage tank; is the temperature loss coefficient; is the activation function, when When greater than or equal to 0, ,when When it is less than 0, .

4. A small-scale waste heat power generation control method according to claim 1, characterized in that: The obtaining of the predicted water volume of the secondary heat storage tank includes: Obtaining a water volume change value of the first-level heat storage tank between time nodes corresponding to two adjacent opening iteration variables; Based on the water volume change value, the predicted residual water volume of the first-level thermal storage tank at any time point is calculated; It is determined whether the current water volume of the primary heat storage tank is greater than the predicted residual water volume, and the predicted water volume of the secondary heat storage tank is calculated based on the determination result.

5. A small-scale waste heat power generation control method according to claim 4, characterized in that: The calculating the predicted water volume of the secondary heat storage tank based on the judgment result includes: If the current water volume of the primary heat storage tank is greater than or equal to the predicted residual water volume, determining the predicted water volume of the secondary heat storage tank as the standard water volume of the secondary heat storage tank; If the current water volume of the primary heat storage tank is less than the predicted residual water volume, the predicted water consumption of the secondary heat storage tank itself is predicted, and the predicted water volume of the secondary heat storage tank is calculated based on the standard water volume of the secondary heat storage tank and the predicted water consumption itself.

6. A small-scale waste heat power generation control method according to claim 5, characterized in that: The predicting of the water consumption of the secondary heat storage tank itself includes: Obtain the average water flow rate of the regulating valve between the primary heat storage tank and any secondary heat storage tank; Based on the average water flow, the overall predicted water consumption of the secondary thermal storage tank at any time node is calculated; Obtaining a target time node when the current water volume of the first-level heat storage tank is less than the predicted residual water volume, and calculating the consumption time of the second-level heat storage tank consuming its own water volume based on the target time node; Based on the consumption time and the overall predicted water consumption, the predicted water consumption of the secondary thermal storage tank itself is calculated.

7. A small-scale waste heat power generation control method according to any one of claims 4 to 6, characterized in that: The expression for the predicted residual water volume of the first-level thermal storage tank at any time point is: ； In the formula, For The predicted residual water volume in the primary thermal storage tank at the time node; for The time node corresponding to The number of iteration steps before the opening iteration variable; The water volume change value of the first-level thermal storage tank for each iteration step; For the The opening iteration variable corresponds to The superposition value of all water inflows before the time node, the water inflow is calculated by the opening of the control valve and the valve information of the control valve.

8. A small-scale waste heat power generation control method according to claim 7, characterized in that: The expression of the water reserve influence coefficient of the secondary thermal storage tank is: ； ； In the formula, for The time node corresponds to Water reserve influence coefficient of each secondary thermal storage tank; For The time node corresponds to The predicted water volume of each secondary thermal storage tank; For the Standard water volume of each secondary thermal storage tank; for The minimum value of the water reserve influence coefficient of all secondary thermal storage tanks corresponding to the time node is selected As in The water reserve influence coefficient of all the secondary thermal storage tanks at the time node.

9. A small-scale waste heat power generation control method according to claim 1, characterized in that: The expression of the target cost function is: In the formula, is the total number of opening iteration variables; for Temperature influence coefficient at time node; is the water volume warning line parameter; for Water reserve impact coefficient corresponding to the time node; is the activation function, when When greater than 0, = ,when When it is less than or equal to 0, =0.

10. A small waste heat power generation control system, characterized in that: include: A processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, a small-scale waste heat power generation control method according to any one of claims 1 to 9 is implemented.

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