Electric heater control method and device based on cascade PID and electronic equipment

Abstract

The application provides a cascade PID-based electric heater control method and device and electronic equipment, which are applied to a molten salt energy storage electric heating system, and the molten salt energy storage electric heating system comprises multiple electric heaters. The method comprises the following steps: acquiring a total power set value of the molten salt energy storage electric heating system; inputting the total power set value into a cascade PID outer ring to obtain an electric heater outlet molten salt temperature set value; collecting a molten salt pump frequency and an ambient temperature, and collecting an inlet molten salt temperature of each electric heater; determining a power set value of each electric heater according to the electric heater outlet molten salt temperature set value, the molten salt pump frequency, the ambient temperature, and the inlet molten salt temperature of each electric heater; and inputting the power set value of each electric heater into a cascade PID inner ring to control the power of each electric heater. The method controls each electric heater through the cascade PID mode, which can not only reduce the labor cost, but also realize real-time control.

Description

Technical Field

[0001] This application relates to the field of molten salt energy storage technology, and in particular to a method, apparatus and electronic equipment for controlling an electric heater based on cascade PID. Background Technology

[0002] Molten salt energy storage, combined with thermal power units, can store the unit's output energy during off-peak hours and release the stored energy during peak hours, effectively improving the unit's peak-shaving capacity. The main types of molten salt energy storage include solar thermal energy storage, high-temperature and high-pressure steam energy storage, and electric heating energy storage. Among these, electric heating energy storage utilizes a high-power electric heater to convert electrical energy into heat energy stored in molten salt. Its advantages include a simple and reliable system, fast heat storage rate, and a wide adjustment range, enabling it to assist thermal power generating units in peak-shaving and frequency regulation.

[0003] As energy storage systems become increasingly larger while the power of individual electric heaters is limited, molten salt energy storage electric heating systems typically employ multiple electric heaters operating in parallel. However, currently, controlling multiple electric heaters requires significant manpower and is difficult to achieve in real-time control. Summary of the Invention

[0004] To address the aforementioned issues, this application provides a method, apparatus, and electronic device for controlling an electric heater based on cascaded PID control.

[0005] According to a first aspect of this application, a cascade PID-based electric heater control method is provided, applied to a molten salt energy storage electric heating system, wherein the molten salt energy storage electric heating system includes multiple electric heaters, and the method includes:

[0006] Obtain the total power setpoint of the molten salt energy storage electric heating system;

[0007] The total power setpoint is input to the outer loop of the cascade PID controller to obtain the setpoint for the molten salt temperature at the outlet of the electric heater; wherein, the outer loop of the cascade PID controller is used to control the setpoint for the molten salt temperature at the outlet of the electric heater based on the total power setpoint and the real-time total power value.

[0008] Collect the molten salt pump frequency and ambient temperature, and collect the inlet molten salt temperature of each electric heater;

[0009] The power setting value of each electric heater is determined based on the set value of the molten salt outlet temperature of the electric heater, the frequency of the molten salt pump, the ambient temperature, and the inlet molten salt temperature of each electric heater.

[0010] The power setpoint of each electric heater is input into the inner loop of the cascade PID controller to control the power of each electric heater; the inner loop of the cascade PID controller is used to adjust the power of each electric heater.

[0011] In some embodiments of this application, the method further includes:

[0012] The real-time power of each electric heater after adjustment is summed to determine the total real-time power value, and the total real-time power value is fed back to the outer loop of the cascade PID controller.

[0013] As one possible implementation, the power setting value for each electric heater is determined based on the electric heater outlet molten salt temperature setpoint, the molten salt pump frequency, the ambient temperature, and the inlet molten salt temperature of each electric heater, including:

[0014] For each electric heater, the setpoint of the molten salt temperature at the outlet of the electric heater, the frequency of the molten salt pump, the ambient temperature, and the inlet temperature of the electric heater are input into the power prediction model corresponding to the electric heater to obtain the power setpoint of the electric heater. The power prediction model is a neural network model that has learned the mapping relationship between the setpoint of the molten salt temperature at the outlet of the electric heater, the frequency of the molten salt pump, the ambient temperature, the inlet temperature of the electric heater, and the power setpoint of the electric heater.

[0015] According to a second aspect of this application, a cascaded PID-based electric heater control device is provided, applied to a molten salt energy storage electric heating system, wherein the molten salt energy storage electric heating system includes multiple electric heaters, and the device includes:

[0016] The acquisition module is used to acquire the total power setpoint of the molten salt energy storage system;

[0017] The first input module is used to input the total power setpoint to the cascade PID outer loop to obtain the electric heater outlet molten salt temperature setpoint; wherein, the cascade PID outer loop is used to control the electric heater outlet molten salt temperature setpoint according to the total power setpoint and the real-time total power value.

[0018] The data acquisition module is used to acquire the frequency of the molten salt pump and the ambient temperature, as well as the inlet molten salt temperature of each electric heater;

[0019] The determination module is used to determine the power setting value of each electric heater based on the set value of the molten salt temperature at the outlet of the electric heater, the frequency of the molten salt pump, the ambient temperature, and the inlet molten salt temperature of each electric heater.

[0020] The second input module is used to input the power setpoint of each electric heater into the inner loop of the cascade PID controller to control the power of each electric heater; wherein, the inner loop of the cascade PID controller is used to adjust the power of each electric heater.

[0021] In some embodiments of this application, the device further includes:

[0022] The feedback module is used to sum the real-time power of each electric heater after adjustment, determine the total real-time power value, and feed the total real-time power value back to the outer loop of the cascade PID controller.

[0023] As one possible implementation, the determining module is specifically used for:

[0024] For each electric heater, the setpoint of the molten salt temperature at the outlet of the electric heater, the frequency of the molten salt pump, the ambient temperature, and the inlet temperature of the electric heater are input into the power prediction model corresponding to the electric heater to obtain the power setpoint of the electric heater. The power prediction model corresponding to the electric heater is a neural network model that has learned the mapping relationship between the setpoint of the molten salt temperature at the outlet of the electric heater, the frequency of the molten salt pump, the ambient temperature, the inlet temperature of the electric heater, and the power setpoint of the electric heater.

[0025] According to a third aspect of the embodiments of this application, an electronic device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, it implements the method described in the first aspect above.

[0026] According to a fourth aspect of this application, a computer-readable storage medium is provided having a computer program stored thereon that, when executed by a processor, implements the method described in the first aspect above.

[0027] According to the technical solution of this application, the total power setpoint of the molten salt energy storage electric heating system is input into the outer loop of the cascade PID controller to obtain the molten salt temperature setpoint at the outlet of the electric heater. The molten salt pump frequency, ambient temperature, and the inlet molten salt temperature of each electric heater are also collected. Based on the molten salt temperature setpoints at the outlets of the electric heaters, the pump frequency, ambient temperature, and the inlet molten salt temperatures, the power setpoint for each electric heater is determined. Then, the temperature setpoints of each electric heater are input into the outer loop of the cascade PID controller to control the power of each heater. This solution uses a cascade PID controller to control the power of each electric heater, which not only reduces labor costs but also enables real-time control of each heater. Furthermore, this control method ensures a uniform molten salt temperature distribution at the outlet of each electric heater, improving both the system's energy storage capacity and its safety.

[0028] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0029] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0030] Figure 1 A flowchart illustrating an electric heater control method based on cascaded PID control provided in an embodiment of this application;

[0031] Figure 2 This is a structural example diagram of a molten salt energy storage electric heating system according to an embodiment of this application;

[0032] Figure 3 This is an example diagram of the network structure of a power prediction model in an embodiment of this application;

[0033] Figure 4 This is a schematic diagram of the cascaded PID control in the embodiments of this application;

[0034] Figure 5 A structural block diagram of an electric heater control device based on cascaded PID provided in an embodiment of this application;

[0035] Figure 6 This is a structural block diagram of an electronic device provided in an embodiment of this application. Detailed Implementation

[0036] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0037] It should be noted that molten salt energy storage technology is an emerging energy storage technology that can store energy during periods of low grid demand and release it during periods of high demand to balance the grid's supply and demand. The application of this technology can not only improve the stability and reliability of the grid but also reduce energy consumption and carbon emissions, thus contributing to sustainable development. Although this technology is still in its early stages of development, its potential has already attracted widespread attention and research. In the future, with continuous technological improvements and cost reductions, molten salt energy storage technology will play an increasingly important role in the energy sector. Furthermore, the development of this technology will promote the popularization of electric vehicles and the utilization of renewable energy, providing broader development space for building a low-carbon and environmentally friendly society. In conclusion, molten salt energy storage technology is a highly anticipated technology that will make significant contributions to our energy transition and sustainable development.

[0038] Molten salt energy storage, combined with thermal power units, can store the unit's output energy during off-peak hours and release the stored energy during peak hours, effectively improving the unit's peak-shaving capacity. Under existing peak-shaving policies, considerable peak-shaving benefits can be obtained. The main types of molten salt energy storage include solar thermal energy storage, high-temperature and high-pressure steam energy storage, and electric heating energy storage. Among them, electric heating energy storage utilizes a high-power electric heater to convert electrical energy into heat energy stored in molten salt. Its advantages include a simple and reliable system, fast heat storage rate, and wide adjustment range, enabling it to assist thermal power generating units in peak-shaving and frequency regulation.

[0039] As energy storage systems become increasingly larger while the power of individual electric heaters is limited, molten salt energy storage electric heating systems typically employ multiple electric heaters operating in parallel. However, currently, controlling multiple electric heaters requires significant manpower and is difficult to achieve in real-time control.

[0040] To address the aforementioned issues, this application provides a method, apparatus, and electronic device for controlling an electric heater based on cascaded PID control.

[0041] Figure 1 This is a flowchart illustrating a cascade PID-based electric heater control method provided in an embodiment of this application. It should be noted that the cascade PID-based electric heater control method in this embodiment can be used in molten salt energy storage electric heating systems, and these systems include multiple electric heaters. Figure 2 This is a schematic diagram of the molten salt energy storage electric heating system in an embodiment of this application, as shown below. Figure 2 As shown, molten salt enters the molten salt pump through molten salt pipelines, and then the molten salt pump delivers the molten salt to n electric heaters, thereby converting electrical energy into heat energy stored in the molten salt. Figure 1 As shown, the method includes the following steps:

[0042] Step 101: Obtain the total power setting value of the molten salt energy storage electric heating system.

[0043] The total power setpoint of the molten salt energy storage electric heating system is given by the upper-level control system (unit DCS) to the molten salt energy storage electric heating system, which is the sum of the power of each electric heater in the molten salt energy storage electric heating system at the current moment. As an example, the unit DCS sends the total power setpoint to the molten salt energy storage electric heating system in real time, so the total power setpoint of the molten salt energy storage electric heating system can be obtained by receiving the total power setpoint sent by the unit DCS in real time.

[0044] Step 102: Input the total power setpoint to the cascade PID outer loop to obtain the electric heater outlet molten salt temperature setpoint; wherein, the cascade PID outer loop is used to control the electric heater outlet molten salt temperature setpoint according to the total power setpoint and the real-time total power value.

[0045] In some embodiments of this application, the input of the cascade PID outer loop is the total power setpoint, and the output of the cascade PID outer loop is the setpoint for the molten salt temperature at the outlet of the electric heater. The real-time total power value refers to the sum of the real-time power of multiple electric heaters in the molten salt energy storage electric heating system at the previous moment. As an example, based on the cascade PID outer loop, the deviation between the total power setpoint and the real-time total power value can be determined, and the setpoint for the molten salt temperature at the outlet of the electric heater can be determined based on this deviation. The cascade PID outer loop has a pre-defined correspondence between the total power deviation and the change in the molten salt temperature at the outlet of the electric heater. Based on the total power deviation, the change in the molten salt temperature at the outlet of the electric heater can be determined, thus allowing the current setpoint for the molten salt temperature at the outlet of the electric heater to be determined based on the previous setpoint and the change in the molten salt temperature at the outlet of the electric heater.

[0046] To enhance the system's energy storage capacity, the outlet molten salt temperature of each electric heater in this embodiment is set to a predetermined value. This means that although the inlet molten salt temperature and flow rate of each electric heater differ, the goal of heater control is to ensure that the outlet molten salt temperature of each heater is the same. In other words, by controlling the electric heaters to make the outlet molten salt temperature of each heater as similar as possible, the system's energy storage capacity can be improved, and the system's safety can also be guaranteed.

[0047] Step 103: Collect the molten salt pump frequency and ambient temperature, and collect the inlet molten salt temperature of each electric heater.

[0048] It should be noted that the molten salt pump frequency, ambient temperature, and inlet molten salt temperature of each electric heater are all parameters collected in real time at the current moment.

[0049] Step 104: Determine the power setting value of each electric heater based on the set value of the molten salt outlet temperature of the electric heater, the frequency of the molten salt pump, the ambient temperature, and the inlet molten salt temperature of each electric heater.

[0050] It is understandable that the upper-level system only provides the total power setting for the molten salt energy storage electric heating system, without specifying the power for each electric heater. Therefore, power allocation for each electric heater is necessary. Since the outlet molten salt temperature of the electric heater is related to the heater power, the inlet molten salt temperature, the molten salt flow rate, and the ambient temperature, and the molten salt flow rate is directly related to the molten salt pump frequency, the power setting for each electric heater can be determined based on the outlet molten salt temperature setting, the molten salt pump frequency, the ambient temperature, and the inlet molten salt temperature of each electric heater.

[0051] In some embodiments of this application, statistical induction can be performed based on a large amount of data to derive a formula for calculating the power setting value of each electric heater based on the temperature difference between the inlet and outlet of the electric heater, the frequency of the molten salt pump, and the ambient temperature. Thus, based on the above formula, the power setting value of each electric heater can be determined according to the molten salt temperature setting value at the outlet of the electric heater, the frequency of the molten salt pump, the ambient temperature, and the inlet molten salt temperature of each electric heater.

[0052] In other embodiments of this application, the power setpoint for each electric heater can be determined by constructing a neural network model. For each electric heater, a power prediction model is constructed. This model is a neural network model that has learned the mapping relationship between the electric heater outlet molten salt temperature, molten salt pump frequency, ambient temperature, and electric heater inlet molten salt temperature and the electric heater's power setpoint. Therefore, for each electric heater, the electric heater outlet molten salt temperature, molten salt pump frequency, ambient temperature, and electric heater inlet molten salt temperature can be input into the power prediction model corresponding to that electric heater to obtain the electric heater's power setpoint.

[0053] As one possible implementation, the power prediction model for each electric heater can be an RBF neural network model. This RBF neural network model is trained based on historical data from the commissioning and trial operation phases of the molten salt energy storage electric heating system, resulting in a trained power prediction model. For each electric heater's power prediction model, the training samples include parameter samples of the heater at various times. Each set of parameter samples includes the outlet molten salt temperature, molten salt pump frequency, ambient temperature, and inlet molten salt temperature at the corresponding time. The label for each training sample is the power setpoint of the electric heater at the corresponding time. The initial power prediction model is trained by inputting the training samples, resulting in a trained power prediction model.

[0054] As an example, such as Figure 3 As shown, the power prediction model for each electric heater can be an RBF neural network model, which includes an input layer, a hidden layer, and an output layer. The input layer receives the input data, the hidden layer performs the nonlinear mapping, and the output layer outputs the prediction results. The input layer has 4 nodes, while the number of nodes in the hidden layer is unlimited. Figure 3 The diagram illustrates the concept with 5 nodes in the hidden layer. Taking the power prediction model of the j-th electric heater as an example, the hidden layer can be activated by a Gaussian function, and the output of the i-th node in the hidden layer can be calculated using formula (1):

[0055]

[0056] in, It is the output of the i-th node in the hidden layer; It is the input sample vector. x1, x2, x3, and x4 are the inlet molten salt temperatures T of the j-th electric heater, respectively. j.in The outlet molten salt temperature T of the j-th electric heater j.out Molten salt pump frequency f, ambient temperature T tem ; The center vector of the Gaussian function; σ i It is a standardized constant.

[0057] The output layer of the power prediction model for the j-th electric heater can perform a weighted calculation of the output results of the hidden layer to output the predicted power of the j-th electric heater. For example, the output of the power prediction model for the j-th electric heater can be calculated using formula (2):

[0058]

[0059] Where y is the output of the neural network, that is, the output quantity is the power P of the j-th electric heater. j ;w i These are the weighting coefficients from the hidden layer to the output layer; u i This is the output of the i-th node in the hidden layer.

[0060] Step 105: Input the power setpoint of each electric heater into the inner loop of the cascade PID controller to control the power of each electric heater; wherein, the inner loop of the cascade PID controller is used to adjust the power of each electric heater.

[0061] In other words, the power setpoint of each electric heater is input into the inner loop of the cascade PID controller, so that the power of each electric heater is adjusted to the power setpoint of the corresponding electric heater based on the inner loop of the cascade PID controller, thereby realizing the power distribution of each electric heater in the molten salt energy storage electric heating system.

[0062] In some embodiments of this application, the control quantity of the inner loop of the cascaded PID is the conduction angle of the thyristor. When the conduction angle of the thyristor changes, the voltage and current applied to the electric heater are changed. The real-time power of the electric heater can be obtained through the voltage transformer, the current transformer and the power meter.

[0063] Furthermore, to achieve cascaded PID outer loop control, the method may include:

[0064] Step 106: Sum the real-time power of each electric heater after adjustment to determine the total real-time power value, and feed the total real-time power value back to the outer loop of the cascade PID controller.

[0065] The adjusted real-time power is the real-time power adjusted in step 105.

[0066] Figure 4 This is a schematic diagram of the cascaded PID control in an embodiment of this application. Figure 4 As shown, based on the outer loop of the cascaded PID controller, the total power setpoint P of the molten salt energy storage electric heating system is calculated. set Obtain the setpoint T for the molten salt temperature at the outlet of the electric heater. set Electric heater outlet molten salt temperature setpoint T set The power prediction model NN is input to each electric heater. i In this process, the conduction angle of the thyristor of each electric heater is obtained. Based on the inner loop of the cascaded PID controller, the conduction angle of the thyristor of each electric heater is controlled to obtain the real-time power P of each electric heater. i And the real-time power P of each electric heater i The total power P of the electric heater is obtained by summing the values, and the total power P is fed back to the outer loop of the cascaded PID controller.

[0067] According to the cascade PID-based electric heater control method of this application embodiment, the total power setpoint of the molten salt energy storage electric heating system is input into the outer loop of the cascade PID to obtain the molten salt temperature setpoint at the outlet of the electric heater. The molten salt pump frequency, ambient temperature, and the inlet molten salt temperature of each electric heater are also collected. Based on the molten salt temperature setpoint at the outlet of the electric heater, the molten salt pump frequency, the ambient temperature, and the inlet molten salt temperature of each electric heater, the power setpoint of each electric heater is determined. Then, the temperature setpoint of each electric heater is input into the outer loop of the cascade PID to control the power of each electric heater. This solution controls the power of each electric heater through cascade PID, which not only reduces labor costs but also enables real-time control of each electric heater. Furthermore, this control method ensures a uniform molten salt temperature distribution at the outlet of each electric heater, which not only improves the energy storage capacity of the system but also enhances the system's safety.

[0068] To achieve the above embodiments, this application provides an electric heater control device based on cascaded PID.

[0069] Figure 5 This is a structural block diagram of an electric heater control device based on cascade PID control, provided in an embodiment of this application. It should be noted that the electric heater control device based on cascade PID control in this embodiment is applied to a molten salt energy storage electric heating system, and this molten salt energy storage electric heating system includes multiple electric heaters. The device includes:

[0070] The acquisition module 501 is used to acquire the total power setpoint of the molten salt energy storage system;

[0071] The first input module 502 is used to input the total power setpoint to the cascade PID outer loop to obtain the electric heater outlet molten salt temperature setpoint; wherein, the cascade PID outer loop is used to control the electric heater outlet molten salt temperature setpoint according to the total power setpoint and the real-time total power value.

[0072] The data acquisition module 503 is used to acquire the frequency of the molten salt pump and the ambient temperature, and to acquire the inlet molten salt temperature of each electric heater;

[0073] The determination module 504 is used to determine the power setting value of each electric heater based on the set value of the molten salt temperature at the outlet of the electric heater, the frequency of the molten salt pump, the ambient temperature, and the inlet molten salt temperature of each electric heater.

[0074] The second input module 505 is used to input the power setpoint of each electric heater into the cascade PID inner loop to control the power of each electric heater; wherein, the cascade PID inner loop is used to adjust the power of each electric heater.

[0075] In some embodiments of this application, the device further includes:

[0076] Feedback module 506 is used to sum the real-time power of each electric heater after adjustment, determine the real-time value of the total power, and feed the real-time value of the total power back to the outer loop of the cascade PID.

[0077] As one possible implementation, the determining module 504 is specifically used for:

[0078] For each electric heater, the setpoint of the molten salt temperature at the outlet of the electric heater, the frequency of the molten salt pump, the ambient temperature, and the inlet temperature of the electric heater are input into the power prediction model corresponding to the electric heater to obtain the power setpoint of the electric heater. The power prediction model corresponding to the electric heater is a neural network model that has learned the mapping relationship between the setpoint of the molten salt temperature at the outlet of the electric heater, the frequency of the molten salt pump, the ambient temperature, the inlet temperature of the electric heater, and the power setpoint of the electric heater.

[0079] The electric heater control device based on cascade PID according to an embodiment of this application obtains the molten salt outlet temperature setpoint of the electric heater by inputting the total power setpoint of the molten salt energy storage electric heating system into the outer loop of the cascade PID controller. It also collects the molten salt pump frequency, ambient temperature, and the inlet molten salt temperature of each electric heater. Based on the molten salt outlet temperature setpoint, molten salt pump frequency, ambient temperature, and inlet molten salt temperature of each electric heater, the power setpoint of each electric heater is determined. Then, the temperature setpoint of each electric heater is input into the outer loop of the cascade PID controller to control the power of each electric heater. This solution controls the power of each electric heater using cascade PID, which not only reduces labor costs but also enables real-time control of each electric heater. Furthermore, this control method ensures a uniform molten salt outlet temperature distribution for each electric heater, improving both the system's energy storage capacity and its safety.

[0080] To implement the above embodiments, this application provides an electronic device and a computer-readable storage medium.

[0081] Figure 6 This is a block diagram of an electronic device for implementing a cascaded PID-based electric heater control method according to embodiments of this application. The term "computer device" is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The term "electronic device" can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the present application described and / or claimed herein.

[0082] like Figure 6 As shown, the electronic device includes a memory 610, a processor 620, and a computer program 630 stored in the memory and executable on the processor. The various components are interconnected via different buses and can be mounted on a common motherboard or otherwise as required. The processor can process instructions executed within the electronic device, including instructions stored in or on the memory to display graphical information of a GUI on an external input / output device (such as a display device coupled to an interface). In other embodiments, multiple processors and / or multiple buses can be used with multiple memories and multiple memory modules, if desired. Similarly, multiple electronic devices can be connected, each providing some of the necessary operations (e.g., as a server array, a group of blade servers, or a multiprocessor system).

[0083] The memory 610 is the non-transitory computer-readable storage medium provided in this application. The memory stores instructions executable by at least one processor to cause the at least one processor to perform the methods of the above embodiments. The non-transitory computer-readable storage medium of this application stores computer instructions for causing a computer to perform the methods described in the above embodiments.

[0084] The memory 610, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the program instructions / modules corresponding to the methods in the above embodiments. The processor 620 executes various functional applications and data processing of the server by running the non-transitory software programs, instructions, and modules stored in the memory 610, thereby implementing the methods in the above embodiments.

[0085] The memory 610 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the electronic device for implementing the methods in the above embodiments. Furthermore, the memory 610 may include high-speed random access memory and may also include non-transient memory, such as at least one disk storage device, flash memory device, or other non-transient solid-state storage device. In some embodiments, the memory 610 may optionally include memory remotely located relative to the processor 620, and these remote memories can be connected via a network to the electronic device for implementing the methods in the above embodiments. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0086] The electronic device used in the methods described in the above embodiments may further include an input device 640 and an output device 650. The processor 620, memory 610, input device 640, and output device 650 may be connected via a bus or other means. Figure 6 Taking the example of a connection between China and Israel via a bus.

[0087] Input device 640 can receive input numerical or character information, and generate key signal inputs related to user settings and function control of the electronic device, such as a touch screen, keypad, mouse, trackpad, touchpad, joystick, one or more mouse buttons, trackball, joystick, etc. Output device 650 may include a display device, auxiliary lighting device (e.g., LED), and haptic feedback device (e.g., vibration motor). The display device may include, but is not limited to, a liquid crystal display (LCD), a light-emitting diode (LED) display, and a plasma display. In some embodiments, the display device may be a touch screen.

[0088] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0089] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0090] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0091] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0092] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0093] Those skilled in the art will understand that all or part of the steps of the methods described in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it includes one or a combination of the steps of the method embodiments. The storage medium mentioned above can be a read-only memory, a magnetic disk, or an optical disk, etc.

[0094] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0095] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A cascade PID-based electric heater control method, characterized by, The method, applied to a molten salt energy storage electric heating system, wherein the molten salt energy storage electric heating system includes multiple electric heaters, comprises: Obtain the total power setpoint of the molten salt energy storage electric heating system; The total power setpoint is input to the outer loop of the cascade PID controller to obtain the setpoint for the molten salt temperature at the outlet of the electric heater; wherein, the outer loop of the cascade PID controller is used to control the setpoint for the molten salt temperature at the outlet of the electric heater based on the total power setpoint and the real-time value of the total power. The frequency of the molten salt pump and the ambient temperature were collected, as well as the inlet molten salt temperature of each of the electric heaters. The power setting value of each electric heater is determined based on the set value of the molten salt outlet temperature of the electric heater, the frequency of the molten salt pump, the ambient temperature, and the inlet molten salt temperature of each electric heater. The power setpoint of each electric heater is input to the inner loop of the cascade PID controller to control the power of each electric heater; wherein, the inner loop of the cascade PID controller is used to adjust the power of each electric heater. Also includes: The real-time power of each electric heater after adjustment is summed to determine the total real-time power value, and the total real-time power value is fed back to the outer loop of the cascade PID controller. The step of determining the power setting value of each electric heater based on the set value of the molten salt outlet temperature of the electric heater, the frequency of the molten salt pump, the ambient temperature, and the inlet molten salt temperature of each electric heater includes: For each electric heater, the setpoint of the molten salt outlet temperature of the electric heater, the frequency of the molten salt pump, the ambient temperature, and the molten salt inlet temperature of the electric heater are input into the power prediction model corresponding to the electric heater to obtain the power setpoint of the electric heater; wherein, the power prediction model is a neural network model that has learned the mapping relationship between the molten salt outlet temperature of the electric heater, the frequency of the molten salt pump, the ambient temperature, the molten salt inlet temperature of the electric heater, and the power setpoint of the electric heater.

2. A control device for an electric heater based on cascade PID control, characterized in that, An electric heating device for molten salt energy storage systems, wherein the molten salt energy storage system includes multiple electric heaters, the device comprising: The acquisition module is used to acquire the total power setpoint of the molten salt energy storage system; The first input module is used to input the total power setpoint to the cascade PID outer loop to obtain the electric heater outlet molten salt temperature setpoint; wherein, the cascade PID outer loop is used to control the electric heater outlet molten salt temperature setpoint according to the total power setpoint and the real-time total power value; The data acquisition module is used to acquire the molten salt pump frequency and ambient temperature, and to acquire the inlet molten salt temperature of each of the electric heaters; The determining module is used to determine the power setting value of each electric heater based on the set value of the molten salt outlet temperature of the electric heater, the frequency of the molten salt pump, the ambient temperature, and the inlet molten salt temperature of each electric heater. The second input module is used to input the power setpoint of each electric heater to the inner loop of the cascade PID controller to control the power of each electric heater; wherein the inner loop of the cascade PID controller is used to adjust the power of each electric heater. Also includes: The feedback module is used to sum the real-time power of each electric heater after adjustment, determine the total real-time power value, and feed the total real-time power value back to the outer loop of the cascaded PID controller. The determining module is specifically used for: For each electric heater, the setpoint of the molten salt outlet temperature, the frequency of the molten salt pump, the ambient temperature, and the molten salt inlet temperature of the electric heater are input into the power prediction model corresponding to the electric heater to obtain the power setpoint of the electric heater; wherein, the power prediction model corresponding to the electric heater is a neural network model that has learned the mapping relationship between the setpoint of the molten salt outlet temperature, the frequency of the molten salt pump, the ambient temperature, the molten salt inlet temperature of the electric heater, and the power setpoint of the electric heater.

3. An electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the method as described in claim 1.

4. A computer-readable storage medium for storing a computer program thereon, characterized in that, When the computer program is executed by a processor, it implements the method as described in claim 1.

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