A waste heat power generation system without grid connection

Abstract

The present application belongs to the technical field of power generation, and particularly relates to a waste heat power generation system without grid connection, which is provided with a waste heat power generation unit and a switch cabinet group, wherein the waste heat power generation unit is a device for converting waste heat into electric energy, the switch cabinet group is a device for transmitting the electric energy generated by the waste heat to local loads for power supply, and the switch cabinet group is connected with a municipal power grid; on one hand, the waste heat power generation unit and the municipal power grid are connected, and on the other hand, the electric energy generated by the waste heat power generation unit is isolated from the municipal power grid, so that the purpose of not being connected with the grid is achieved; and in the process of power transmission and power consumption, the control system is used for optimization. The present application can solve the problem of poor utilization of steam waste heat in the prior art.

Description

Technical Field

[0001] The present invention belongs to the technical field of power generation, and in particular relates to a waste heat power generation system that is connected to the grid but not connected to the grid. Background Art

[0002] In modern industrial production, sulfuric acid processing is undoubtedly a key cornerstone of the chemical industry. The steam generated by the boilers in the sulfuric acid production process contains considerable heat, and theoretically, this waste heat has great potential for reuse. However, traditional sulfuric acid processing areas have long employed relatively crude and rudimentary methods to treat this waste heat, resulting in low utilization efficiency.

[0003] In practice, some companies only use waste steam heat for basic, limited-heat preheating steps, such as simple initial heating of raw materials or some process water. This method extracts only a tiny fraction of the energy from the waste steam, leaving a significant amount of heat energy trapped in the steam and subsequently released into the atmosphere. Therefore, improving the efficiency of waste steam heat from boilers in sulfuric acid production areas, converting it into electricity and effectively utilizing it for local loads, can reduce companies' electricity costs and dependence on the external power grid, offering significant economic and environmental benefits. However, currently, specialized and efficient grid-connected and off-grid power generation technologies for waste steam from boilers in sulfuric acid production areas still have numerous shortcomings, necessitating an urgent need for innovative solutions. Summary of the Invention

[0004] The technical problem solved by the present invention is to provide a waste heat power generation system that is connected to the grid but not connected to the grid, so as to solve the problem of poor utilization of steam waste heat in the prior art.

[0005] The present invention provides a basic solution: a waste heat power generation system that is connected to the grid but not connected to the grid, comprising a waste heat generator set, a switch cabinet set, and a control system. The waste heat generator set is connected to the switch cabinet set, the waste heat generator set is used to convert waste heat into electrical energy and transmit it to the switch cabinet set, the switch cabinet set is used to receive the electrical energy transmitted by the waste heat generator set and transmit it to the local load power grid through distribution processing, and the control system is connected to the waste heat generator set and the switch cabinet set;

[0006] The control system includes a monitoring module, a data acquisition module, a data preprocessing module, a digital twin management module, and a transmission strategy optimization module, wherein:

[0007] The monitoring module is installed at the equipment components in the waste heat generator set and the switchgear group to monitor the operating data and environmental data of each equipment component;

[0008] The data acquisition module communicates wirelessly with the monitoring module, and the data acquisition module is used to receive the operating data of each device component in the waste heat generator set and the switch cabinet group monitored by the monitoring module, as well as parameter information and structural data of the waste heat generator set and the switch cabinet group;

[0009] The data preprocessing module is used to preprocess the acquired operating data, parameter information and structural data before modeling;

[0010] The digital twin management module is used to build a digital image of the waste heat power generation equipment based on pre-processed parameter information and structural data, and to drive the simulation of changes in the digital image of the waste heat power generation equipment based on pre-processed operating data;

[0011] The digital twin management module has preset element models for the waste heat power generation scenario. The data acquisition module is also used to obtain scene elements of the scene in which the waste heat power generation system is located. Based on the scene elements, the preset element models are called to build a digital mirror of the waste heat power generation scenario. The simulation of changes in the digital mirror of the waste heat power generation scenario is driven by environmental data.

[0012] The transmission strategy optimization module is used to use the simulation results of the changes in the digital image of the waste heat power generation equipment and the simulation results of the changes in the digital image of the waste heat power generation scenario as the dynamic model of the waste heat power generation system, and to build a power demand forecast model based on the local load power consumption data; the transmission strategy optimization module is also used to call the target optimization algorithm and the power demand forecast model to dynamically adjust the dynamic model of the waste heat power generation system, and after verifying the dynamic adjustment results, generate a waste heat power generation system adjustment command and transmit it to the digital twin management module;

[0013] The digital twin management module is also used to control the digital image of the waste heat power generation equipment to perform simulation evolution according to the waste heat power generation system adjustment command, and to control the operation of the waste heat generator set and the switch cabinet group according to the simulation evolution results.

[0014] The principle and advantage of the present invention are as follows: in this solution, for the effective utilization of waste steam heat, a waste heat generator set and a switchgear set are provided, wherein the waste heat generator set is a device that converts waste heat into electrical energy, and the switchgear set is a device that transmits the electrical energy generated by the waste heat to local loads for power supply. The switchgear set is connected to the city power grid, which, on the one hand, implements the grid connection of the waste heat generator set and the city power grid, and on the other hand, isolates the electrical energy generated by the waste heat generator set from being transmitted to the city power grid, thereby achieving the purpose of not being connected to the grid.

[0015] In the above-mentioned waste heat power generation system that is connected to the grid but not connected to the grid, its transmission and power consumption optimization is achieved through the control system. Specifically, the operating data and environmental data of the waste heat generator set and the switchgear group are first collected, and the parameter information and structural data of the waste heat generator set and the switchgear group are obtained at the same time. A digital image of the waste heat power generation equipment is constructed based on the parameter information and structural data, and a digital image of the waste heat power generation scene is constructed based on the environmental data. At the same time, the digital image of the waste heat power generation equipment and the digital image of the waste heat power generation scene are driven to perform change simulation based on the operating data. From the change simulation results, the parameter data of the actual waste heat power generation system used for power consumption optimization can be extracted. In this way, the optimal transmission strategy is obtained by combining the transmission strategy optimization module with the target optimization algorithm and the power demand prediction model to maximize the utilization of steam waste heat.

[0016] Furthermore, the power transmission strategy optimization module includes a power consumption prediction model construction unit and a power transmission optimization unit;

[0017] The power consumption prediction model building unit is used to collect historical power consumption data of local loads and build a power demand prediction model based on the characteristics of the historical power consumption data. The expression is:

[0018]

[0019] Among them, B is the backshift operator, BP L (k) = P l (k-1), θ(B)=1+θ1B+…+θ q B q ; represents the d-order difference operator, ∈(k) represents the white noise sequence, represents the autoregressive coefficient, θ q represents the moving average coefficient;

[0020] A time window and a power optimization objective function are preset in the power transmission optimization unit. The power transmission optimization unit calls the preset time window to obtain the power demand forecast data output by the power demand forecast model, and after the preset time window is filled, calculates the current power optimization control data of the local load according to the power demand forecast data in the preset time window and the preset power optimization objective function.

[0021] Beneficial effects: By building an electricity demand forecasting model, the local load electricity demand can be predicted. The predicted value is used to calculate the electricity optimization control data based on the electricity optimization objective function. This data is used as the control quantity for subsequent electricity regulation, such as turbine steam inlet regulation, to achieve early control of the regulation control quantity.

[0022] Furthermore, the calculation of the current power consumption optimization control data of the local load according to the power demand forecast data in the preset time window and the preset power consumption optimization objective function is specifically:

[0023] The preset power consumption optimization objective function in the transmission optimization unit is constructed as follows:

[0024]

[0025] Where i = 1, 2, ..., N, N is the prediction time domain, P(k+i|k) is the predicted value of the power generation at the future k+i time based on the current time k, P L (k+i|k) is the predicted value of the local load power consumption at the future k+i time based on the current time k, Δu(k+i) is the control increment at the future k+i time, λ i is the weight coefficient;

[0026] Set constraints, including steam flow constraints, power generation constraints, and control increment constraints. At each sampling time k, based on the current waste heat power generation system dynamic model state and power demand forecast data, call the preset power optimization objective function to calculate the current power optimization control data and generate a control sequence. The control sequence is: Δu(k), Δu(k+1)…Δu(k+N-1);

[0027] The control sequence is sequentially and rollingly applied to the digital image of the waste heat power generation equipment in the dynamic model of the waste heat power generation system in a time sequence to obtain the optimized control result of the digital image of the waste heat power generation equipment.

[0028] Beneficial effect: Through the above processing steps, the regulation and optimization of the waste heat power generation system is achieved, ensuring the effective utilization of steam waste heat.

[0029] Furthermore, the waste heat power generation unit includes a steam turbine, a generator, a medium-pressure steam pipe, a low-pressure steam pipe, a condenser, and a recovery pipe. The medium-pressure steam pipe is connected to the main air inlet of the steam turbine, the low-pressure steam pipe is connected to the auxiliary air inlet of the steam turbine, the steam turbine is connected to the generator through a coupling, and the generator is connected to the switch cabinet group;

[0030] The steam turbine exhaust port is communicated with the condenser inlet, the condenser outlet is communicated with one end of a recovery pipe, and the other end of the recovery pipe is communicated with an external water supply system.

[0031] Beneficial effects: In this scheme, the main function of the waste heat generator set is to effectively utilize the boiler steam in the sulfuric acid operation to generate power. For this, the generated boiler steam is divided into medium pressure steam and low pressure steam according to its pressure. The medium pressure steam is transported to the steam turbine through the medium pressure steam pipeline, and the high pressure and high temperature characteristics drive the impeller of the steam turbine to rotate at high speed, realizing the preliminary conversion of heat energy to mechanical energy. At the same time, the low pressure steam is used as a steam supplement and enters the steam turbine through the low pressure steam pipeline to optimize the work process of the steam turbine and improve the overall energy conversion efficiency of the waste heat generator set.

[0032] At the same time, the exhaust steam in the steam turbine after energy conversion is output to the condenser, where it is condensed into water through heat exchange with cooling water and is recycled to the feedwater system, further improving the energy utilization rate of the entire waste heat generator set.

[0033] Further, the switch cabinet group includes a switch cabinet and a cable, the switch cabinet is provided with device elements for performing electrical isolation, control and protection, the generator in the waste heat generator set is connected to the incoming line end of the switch cabinet through the cable, and the switch cabinet is also connected to the power grid through a power interface and performs grid connection without grid access.

[0034] Beneficial effects: In the switch cabinet assembly, the switch cabinet includes electrical device elements that can effectively distribute, control and monitor the electrical energy generated by the generator in the waste heat generator set, ensuring safe and stable transmission of electrical energy to the local load grid. At the same time, when the power generation of the waste heat generator set is less than the local load demand, the local load is supplemented by the power grid through the switch cabinet, ensuring stable power supply to the local load.

[0035] Further, the digital twin management end includes a device model construction unit, a scene model construction unit, a scene optimization unit and a rendering unit. The device model construction unit is used to construct a digital mirror image of the waste heat power generation equipment according to the parameter information and structure data of each device element in the waste heat generator set and the switch cabinet group. The scene model construction unit is used to construct a digital mirror image of the waste heat power generation scene according to the environmental data at the waste heat generator set and the switch cabinet group, and to call the corresponding preset element model. The scene optimization unit is used to associate the digital mirror image of the waste heat power generation equipment and the digital mirror image of the waste heat power generation scene and generate a digital mirror image of the waste heat power generation system. The scene optimization unit is also used to obtain user operation instructions to perform corresponding operations on the digital mirror image of the waste heat power generation system. The rendering unit is used to render the digital mirror image of the waste heat power generation system and the change simulation of the digital mirror image of the waste heat power generation system after the user instruction operation.

[0036] Beneficial effects: By building a digital mirror of the waste heat power generation system, the operating status of the waste heat power generation system can be visualized and presented to users in real time, making it easier for users to understand the operating conditions of the waste heat power generation system. At the same time, the digital twin technology used can also simulate the aforementioned power optimization plan through the digital mirror, predict the results of the plan in advance, and facilitate timely detection of errors and implementation of corresponding measures. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a functional block diagram of an embodiment of the present invention;

[0038] Figure 2 Schematic diagram of the structure of the waste heat power generation system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0039] The following is further described in detail through specific implementation methods:

[0040] The embodiment is basically as shown in the attached Figure 1 and Figure 2 As shown: A waste heat power generation system that is connected to the grid but not connected to the grid, including a waste heat generator set, a switch cabinet group and a control system. The waste heat generator set is connected to the switch cabinet group. The waste heat generator set is used to convert waste heat into electrical energy and transmit it to the switch cabinet group. The switch cabinet group is used to receive the electrical energy transmitted by the waste heat generator set and transmit it to the local load power grid through distribution processing. The control system is connected to the waste heat generator set and the switch cabinet group. Specifically:

[0041] The waste heat generator set consists of a steam turbine, a generator, an intermediate-pressure steam pipeline, a low-pressure steam pipeline, a condenser, and a recovery pipeline. The steam turbine is connected to the generator via a coupling. Rotation of the turbine blades drives the coupling, which in turn drives the generator, generating electricity that is then transmitted to the switchgear. The intermediate-pressure steam pipeline connects to the main inlet of the steam turbine, and the low-pressure steam pipeline connects to the secondary inlet of the steam turbine. In this embodiment, the intermediate-pressure steam pipeline is constructed from high-temperature, high-pressure, and well-insulating pipes, such as alloy steel pipes. Pipe welding meets process requirements, and a slope of 0.002-0.005 is applied during pipeline installation to facilitate smooth flow of intermediate-pressure steam within the pipeline and prevent condensate accumulation and water hammer. Temperature and pressure monitoring instruments are installed at key locations within the pipeline, such as elbows, tees, or valves, to monitor steam parameter changes in real time. The low-pressure steam pipeline is similar to the above-described configuration, except that lower-cost, qualified pipes can be used.

[0042] The condenser inlet is connected to the turbine exhaust port, and the installation position of the condenser is lower than the turbine exhaust port so that the exhaust steam in the turbine can flow smoothly into the condenser. The condenser outlet is connected to the recovery pipe, and the condensate at the condenser outlet flows through the recovery pipe to the external water supply system for recycling.

[0043] Therefore, in the various equipment structures of the above-mentioned waste heat power generation unit, the boiler in the sulfuric acid operation area generates medium-pressure steam and low-pressure steam during operation. The standard of medium-pressure steam in this application is 2.5 MPa and the temperature is 350°C. The medium-pressure steam enters the main air inlet of the steam turbine through the medium-pressure steam pipe according to the design flow rate of the steam turbine. The medium-pressure steam expands and performs work in the steam turbine, driving the impeller to rotate at high speed, converting the thermal energy of the medium-pressure steam into mechanical energy. At the same time, the speed of the steam turbine itself is precisely controlled by the speed control system, so that the power frequency and output of the generator connected to it are stable at a fixed value;

[0044] During the work of the medium-pressure steam, the steam turbine needs to adjust the amount of low-pressure steam supplemented in a timely manner. That is, when the steam inlet volume of the steam turbine is insufficient or the steam energy decreases, the low-pressure steam is transported to the steam turbine through the low-pressure steam pipeline. In this application, the low-pressure steam used for supplementary steam is maintained at 0.5 MPa and the temperature is 200°C. Therefore, the work of the steam turbine in this solution is achieved through the coordinated cooperation of medium-pressure steam and low-pressure steam, which can improve the energy utilization rate of the steam and keep the output power of the steam turbine stable.

[0045] In this embodiment, the switch cabinet group includes a switch cabinet and corresponding cables. In this embodiment, the switch cabinet adopts the KYN28A-12 type switch cabinet. The switch cabinet is equipped with a series of electrical components such as circuit breakers, contactors, relays, inverters, etc., and is connected to the generator of the waste heat generator set through cables, which can realize the reasonable distribution and control of electric energy. At the same time, according to the demand of the local load, the switch cabinet can accurately transmit electric energy to each electrical equipment or power consumption area. In addition, the switch cabinet also has an interface for connection to the municipal power grid. In this solution, under normal operating conditions, only the grid-connected but not connected to the municipal power grid function is realized, that is, when the local load power demand is less than the power generation of the waste heat generator set, the excess power of the waste heat generator set will not be transmitted to the municipal power grid. When the local load power demand is greater than the power generation of the waste heat generator set, the shortfall is supplemented by the municipal power grid to the local load through the switch cabinet to ensure stable power supply to the local load.

[0046] The control system is connected to the waste heat generator set and the switch cabinet group. The control system includes a monitoring module, a data acquisition module, a data preprocessing module, a digital twin management module and a transmission strategy optimization module. The monitoring module is arranged at the equipment components in the waste heat generator set and the switch cabinet group to monitor the operating data and environmental data of each equipment component; for example, the monitoring module includes various sensors and monitoring cameras. Various sensors are arranged at the equipment components of the waste heat generator set and the switch cabinet group to collect the operating data of each equipment component; at the same time, the monitoring camera collects the environmental data of the waste heat generator set and the switch cabinet group in real time, including real-time video data of the surrounding environment, foreign object detection image data, etc.

[0047] The data acquisition module communicates wirelessly with the monitoring module, wherein the monitoring module transmits the monitored operating data and environmental data to the data acquisition module. In addition to obtaining the operating data and environmental data of the waste heat generator set and the switch cabinet group, the data acquisition module also obtains parameter information and structural data of the waste heat generator set and the switch cabinet group. The waste heat generator set includes a steam turbine, a generator, a medium-pressure steam pipe, a low-pressure steam pipe, a condenser and a recovery pipe, and the switch cabinet group includes a switch cabinet and a cable. By obtaining the parameter information and structural data of the above-mentioned various types of equipment, for example, the parameter information of the steam turbine includes model, specification, rated speed, steam inlet parameters, exhaust parameters, etc., and the structural data includes rotor structure, cylinder structure, bearing type and parameters, steam seal structure, etc., the parameter information and structural data of the above-mentioned various types of equipment are obtained.

[0048] After the operating data, parameter information, and structural data of the waste heat generator set and switchgear group are obtained through the data acquisition module, they are preprocessed and analyzed through the data preprocessing module, such as data cleaning, data association, and data conversion, so that the preprocessed data can meet the input of the digital twin management module.

[0049] The digital twin management module constructs a digital image of the waste heat power generation equipment based on the pre-processed parameter information and structural data of the waste heat power generation unit and switchgear family. In this solution, the generation of the digital image of the waste heat power generation equipment is based on digital twin technology and uses modeling to restore the real waste heat power generation system; further, the digital twin management module drives the digital image of the waste heat power generation equipment to perform change simulation based on the operating data, so that the operating status of each device in the real waste heat power generation system can be obtained through the digital image of the waste heat power generation equipment, and by adjusting the parameters of the digital image of the waste heat power generation equipment, on the one hand, the simulated operating status of the waste heat power generation equipment after parameter adjustment can be seen, and operations can be performed on the real waste heat power generation equipment until the parameters are correct. On the other hand, the digital image of the waste heat power generation equipment can provide real-time feedback to users on the operating status of each device in the real waste heat power generation system.

[0050] After digitally mirroring and simulating changes in the waste heat power generation equipment, the digital twin management module also constructs a digital mirror of the waste heat power generation scene based on the environmental data. Specifically, in the digital twin management module, element models of the waste heat power generation scene are preset. For example, for static objects, they include building models, plant models, etc., and for dynamic objects, they include people and animals, where people include men, women, children, etc., and animals include snakes, rats, and floating or moving foreign objects, such as plastic bags, kites, etc.; in this way, when constructing the digital mirror of the waste heat power generation scene, the monitoring module monitors the characteristics of the objects in the environment where the waste heat generator set and the switch cabinet group are located, and the corresponding scene model is quickly retrieved based on the characteristics, so that the digital mirror of the waste heat power generation scene is quickly constructed, saving computing power resources and high model change efficiency, and requiring low configuration; similarly, according to the operating data of the waste heat power generation equipment scene, or the user input instruction requirements, the scene model in the digital mirror of the waste heat power generation scene is increased or decreased in real time to achieve the purpose of rapid transformation, and the transformation process is implemented by the rendering unit in the digital twin management module.

[0051] In the digital image generated by the above-mentioned digital twin management module, the operation status of the waste heat power generation system can be reflected in real time according to the results of the change simulation. In this regard, in order to improve the high utilization rate of steam waste heat in the waste heat power generation system, it is necessary to improve and optimize the transmission strategy of the waste heat power generation system. Therefore, in this scheme, the dynamic model of the waste heat power generation system is used according to the simulation results of the change of the digital image of the waste heat power generation equipment and the simulation results of the change of the digital image of the waste heat power generation scene. This dynamic model can reflect in real time the relationship between the medium-pressure steam flow, the low-pressure steam flow and the power generation power of the waste heat generator set in the waste heat power generation system, and can also reflect the relationship between the power generation power and the power consumption power between the waste heat generator set and the local load of the switch cabinet combination. Therefore, the operating data obtained from the simulation results of the digital image change can be represented as the operating data of the real waste heat power generation system.

[0052] The power transmission strategy optimization module includes a power consumption forecasting model construction unit and a power transmission optimization unit. The power consumption forecasting model construction unit constructs a power demand forecasting model based on the local load power consumption data. In this solution, the power demand forecasting model construction process is as follows: it is necessary to collect historical data of the local load, including the power demand change curve over time and the load fluctuation pattern in different time periods. To this end, this solution uses an autoregressive moving average model to construct a power demand forecasting model to predict the future power demand of the local load. The expression is:

[0053]

[0054] Among them, B is the backshift operator, BP L (k) = P L (k-1), θ(B)=1+θ1B+…+θ q B q ; represents the d-order difference operator, ∈(k) represents the white noise sequence, represents the autoregressive coefficient, θ q Indicates the moving average coefficient; in the specific implementation, taking the autoregressive moving average model ARIMA (d=1, p=1, q=1) as an example, for the sequence after the first-order difference The expression of the electricity demand forecast model is:

[0055]

[0056] in, is the autoregressive coefficient, θ1 is the moving average coefficient, ∈(k) is the white noise sequence;

[0057] Then the least squares method was used to estimate and the value of θ1;

[0058] Finally, the load demand P at time k+1 is predicted L (k+1), based on the actual k value, the load demand at time k+1 can be obtained.

[0059] After the electricity demand forecasting model building unit builds the electricity demand forecasting model, it outputs electricity demand forecasting data and inputs it into the power transmission optimization unit, wherein the power transmission optimization unit presets a time window and a power optimization objective function. The power transmission optimization unit calls the forecast time window to obtain the electricity demand forecasting data output by the power demand forecasting model. For example, if the preset time window is 3 days, all electricity demand forecasting data of the power demand forecasting model in the next 3 days are input into the preset time window as initial data. Subsequently, after the preset time window is filled, the power transmission optimization unit calculates the current power optimization control data of the local load according to the electricity demand forecasting data in the preset time window and the preset power optimization objective function. Specifically, the calculation process is as follows:

[0060] Step 1: Construct the preset power consumption optimization objective function in the power transmission optimization unit:

[0061]

[0062] Where i = 1, 2, ..., N, N is the prediction time domain, P(k+i|k) is the predicted value of the power generation at the future k+i time based on the current time k, P L (k+i|k) is the predicted value of the local load power consumption at the future k+i time based on the current time k, Δu(k+i) is the control increment at the future k+i time, λ i is the weight coefficient;

[0063] Step 2: Set constraints, including steam flow constraints, power generation constraints, and control increment constraints. At each sampling time k, based on the current waste heat power generation system dynamic model state and power demand forecast data, call the preset power optimization objective function to calculate the current power optimization control data and generate a control sequence. The control sequence is: Δu(k), Δu(k+1)…Δu(k+N-1);

[0064] Step 3: Apply the control sequence to the digital image of the waste heat power generation equipment in the dynamic model of the waste heat power generation system in a rolling manner according to the time sequence to obtain the optimized control result of the digital image of the waste heat power generation equipment.

[0065] Therefore, in this solution, based on the simulation of changes in the digital image of the waste heat power generation equipment in the generated waste heat power generation system and the simulation of changes in the digital image of the waste heat power generation scenario, the control strategy of the entire system is optimized, greatly improving the utilization rate of steam waste heat in the waste heat power generation system in this solution.

[0066] The above are only embodiments of the present invention. Common knowledge such as the known specific structures and characteristics in the scheme are not described in detail here. Ordinary technicians in the field are aware of all common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all existing technologies in the field, and have the ability to apply conventional experimental means before that date. Ordinary technicians in the field can improve and implement this scheme in combination with their own abilities under the inspiration given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention. These will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A waste heat power generation system that is connected to the grid but not connected to the grid, characterized by: It includes a waste heat generator set, a switch cabinet group and a control system. The waste heat generator set is connected to the switch cabinet group. The waste heat generator set is used to convert waste heat into electrical energy and transmit it to the switch cabinet group. The switch cabinet group is used to receive the electrical energy transmitted by the waste heat generator set and transmit it to the local load power grid through distribution processing. The control system is connected to the waste heat generator set and the switch cabinet group. The control system includes a monitoring module, a data acquisition module, a data preprocessing module, a digital twin management module, and a transmission strategy optimization module, wherein: The monitoring module is installed at the equipment components in the waste heat generator set and the switchgear group to monitor the operating data and environmental data of each equipment component; The data acquisition module communicates wirelessly with the monitoring module, and the data acquisition module is used to receive the operating data of each device component in the waste heat generator set and the switch cabinet group monitored by the monitoring module, as well as parameter information and structural data of the waste heat generator set and the switch cabinet group; The data preprocessing module is used to preprocess the acquired operating data, parameter information and structural data before modeling; The digital twin management module is used to build a digital image of the waste heat power generation equipment based on pre-processed parameter information and structural data, and to drive the simulation of changes in the digital image of the waste heat power generation equipment based on pre-processed operating data; The digital twin management module has preset element models for the waste heat power generation scenario. The data acquisition module is also used to obtain scene elements of the scene in which the waste heat power generation system is located. Based on the scene elements, the preset element models are called to build a digital mirror of the waste heat power generation scenario. The simulation of changes in the digital mirror of the waste heat power generation scenario is driven by environmental data. The transmission strategy optimization module is used to use the simulation results of the changes in the digital image of the waste heat power generation equipment and the simulation results of the changes in the digital image of the waste heat power generation scenario as the dynamic model of the waste heat power generation system, and to build a power demand forecast model based on the local load power consumption data; the transmission strategy optimization module is also used to call the target optimization algorithm and the power demand forecast model to dynamically adjust the dynamic model of the waste heat power generation system, and after verifying the dynamic adjustment results, generate a waste heat power generation system adjustment command and transmit it to the digital twin management module; The digital twin management module is also used to control the digital image of the waste heat power generation equipment to perform simulation evolution according to the waste heat power generation system adjustment command, and to control the operation of the waste heat generator set and the switch cabinet group according to the simulation evolution results.

2. The grid-connected but non-grid-connected waste heat power generation system according to claim 1, characterized in that: The power transmission strategy optimization module includes a power consumption prediction model construction unit and a power transmission optimization unit; The power consumption prediction model building unit is used to collect historical power consumption data of local loads and build a power demand prediction model based on the characteristics of the historical power consumption data. The expression is: Among them, B is the backshift operator, BP L (k) = P l (k-1), θ(B)=1+θ1B+…+θ q B q ; represents the d-order difference operator, ∈(k) represents the white noise sequence, represents the autoregressive coefficient, θ q represents the moving average coefficient; A time window and a power optimization objective function are preset in the power transmission optimization unit. The power transmission optimization unit calls the preset time window to obtain the power demand forecast data output by the power demand forecast model, and after the preset time window is filled, calculates the current power optimization control data of the local load according to the power demand forecast data in the preset time window and the preset power optimization objective function.

3. The waste heat power generation system according to claim 2, wherein: The calculation of the current power consumption optimization control data of the local load based on the power demand forecast data within the preset time window and the preset power consumption optimization objective function is specifically: The preset power consumption optimization objective function in the transmission optimization unit is constructed as follows: Where i = 1, 2, ..., N, N is the prediction time domain, P(k+i|k) is the predicted value of the power generation at the future k+i time based on the current time k, P L (k+i|k) is the predicted value of the local load power consumption at the future k+i time based on the current time k, Δu(k+i) is the control increment at the future k+i time, λ i is the weight coefficient; Set constraints, including steam flow constraints, power generation constraints, and control increment constraints. At each sampling time k, based on the current waste heat power generation system dynamic model state and power demand forecast data, call the preset power optimization objective function to calculate the current power optimization control data and generate a control sequence. The control sequence is: Δu(k), Δu(k+1)…Δu(k+N-1); The control sequence is sequentially and rollingly applied to the digital image of the waste heat power generation equipment in the dynamic model of the waste heat power generation system in a time sequence to obtain the optimized control result of the digital image of the waste heat power generation equipment.

4. The grid-connected but non-grid-connected waste heat power generation system according to claim 3, characterized in that: The waste heat power generation unit includes a steam turbine, a generator, a medium-pressure steam pipeline, a low-pressure steam pipeline, a condenser, and a recovery pipeline. The medium-pressure steam pipeline is connected to the main air inlet of the steam turbine, the low-pressure steam pipeline is connected to the secondary air inlet of the steam turbine, the steam turbine is connected to the generator through a coupling, and the generator is connected to the switch cabinet group; The steam turbine exhaust port is communicated with the condenser inlet, the condenser outlet is communicated with one end of a recovery pipe, and the other end of the recovery pipe is communicated with an external water supply system.

5. The grid-connected but non-grid-connected waste heat power generation system according to claim 4, characterized in that: The switch cabinet group includes a switch cabinet and cables. The switch cabinet is equipped with equipment components for performing electrical isolation, control and protection. The generator in the waste heat power generation group is connected to the incoming line end of the switch cabinet through a cable. The switch cabinet is also connected to the mains power grid through a mains power interface, and is connected to the grid with the generator but not to the grid.

6. The waste heat power generation system for grid-connected but not grid-connected power generation according to claim 5, characterized in that: The digital twin management terminal includes a device model construction unit, a scenario model construction unit, a scenario optimization unit, and a rendering unit. The device model construction unit is used to construct a digital image of the waste heat power generation equipment based on the parameter information and structural data of each device component in the waste heat power generation unit and the switch cabinet group; The scene model construction unit is used to call the corresponding preset element model to construct a digital image of the waste heat power generation scene according to the environmental data of the waste heat power generation group and the switch cabinet group; The scene optimization unit is used to associate the digital image of the waste heat power generation equipment with the digital image of the waste heat power generation scene and generate a digital image of the waste heat power generation system. The scene optimization unit is also used to obtain user operation instructions to perform corresponding operations on the digitalization of the waste heat power generation system. The rendering unit is used to render the digital image of the waste heat power generation system, and to render a simulation of the changes in the digital image of the waste heat power generation system after the user instruction operation.

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