Self-adaptive temperature and pressure control method giving consideration to variable load rate and energy consumption characteristics of coal-fired power generation unit

Abstract

The invention discloses a self-adaptive temperature and pressure control method giving consideration to variable load rate and energy consumption characteristics of a coal-fired power generation unit, which comprises the following steps: firstly, for a 75-50% THA load interval section of the coal-fired power generation unit, maintaining an original linear relationship between main steam pressure and load rate, fixing 75% THA load main steam pressure, adjusting 50% THA load main steam pressure, and performing analogue simulation to obtain a temperature and pressure value of the 75-50% THA load interval section of the coal-fired power generation unit; a 50% THA main steam pressure critical target value just meeting different target variable load rates in the load rising and falling process is obtained, then a function model between the 50% THA load main steam pressure critical target value and the variable load rates is established on the basis of the least square method, and the self-adaptive temperature and pressure control method suitable for the load rising and falling process is constructed according to the function model. Therefore, the 50% THA main steam pressure critical target value corresponding to any target variable load rate can be determined, and compared with a self-adaptive temperature and pressure control method and a conventional temperature and pressure control method, the operation flexibility of the unit can be remarkably improved, and the method has very important significance on flexible and efficient operation of the coal-fired power generation unit.

Description

Technical Field

[0001] This invention relates to the field of coal-fired power unit control optimization technology, specifically to an adaptive temperature and pressure control method that takes into account both the variable load rate and energy consumption characteristics of coal-fired power generating units. Background Technology

[0002] The intermittent and fluctuating nature of new energy sources has transformed the power system from experiencing "single-sided disturbance" to "double-sided disturbance" involving both load and power source. This has dramatically increased the peak-shaving and frequency regulation tasks of coal-fired power generating units, which are constantly in a state of frequent load-changing transient processes. Improving the peak-shaving and frequency regulation performance of coal-fired power generating units is an urgent need for the power industry. However, the large delay and inertia characteristics of coal-fired units limit their ability to rapidly change loads. Therefore, it is crucial to clarify the nonlinear regulation characteristics of coal-fired power generating units as load changes, transform their operating methods, and construct temperature and pressure control methods that can achieve rapid load changes.

[0003] Currently, large thermal power generating units typically employ a combined sliding pressure operation mode to achieve safe and economical operation. This mode involves constant pressure operation under high and low loads, and sliding pressure operation under intermediate loads. Since actual operating conditions differ from design conditions, optimizing this mode is of significant importance. When operating under sliding pressure, to increase the unit's load change rate, it is usually necessary to accelerate the combustion of pulverized coal in the furnace, leading to drastic fluctuations in the pressure and temperature of the working fluid within the pipes, thus threatening the safe and stable operation of the unit. Therefore, optimizing pressure control methods during load changes has significant engineering value.

[0004] Maintaining stable key thermodynamic parameters of the unit during load changes is a crucial prerequisite for ensuring safe operation. As the load change rate increases, the fluctuations in unit power, main steam temperature, reheat steam temperature, main steam pressure, and the operating temperatures of different equipment heat exchange surfaces become increasingly drastic, potentially exceeding control limits and thus restricting further increases in the load change rate. To ensure unit flexibility and energy consumption characteristics, it is necessary to explore temperature and pressure control methods for coal-fired power generating units that adapt to rapid load changes. Therefore, this invention proposes an adaptive temperature and pressure control method that considers both the load change rate and energy consumption characteristics of coal-fired power generating units. Summary of the Invention

[0005] To address the lack of flexibility in existing technologies, this invention focuses on temperature and pressure control methods for coal-fired power generating units, aiming to find a method that improves the rate of load change for these units. The objective of this invention is to provide an adaptive temperature and pressure control method that considers both the rate of load change and energy consumption characteristics of coal-fired power generating units. This method achieves an arbitrary target rate of load change within a 75%–50% THA load range, significantly improving the flexibility of unit operation and possessing significant engineering value for realizing flexible, efficient, and economical operation of coal-fired power generating units.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: An adaptive temperature and pressure control method that takes into account both the variable load rate and energy consumption characteristics of coal-fired power generating units includes the following steps: Step S1: Study the 75%~50% THA load range of the coal-fired power generation unit, keep the linear relationship between the main steam pressure and the load rate in this load range unchanged, and fix the main steam pressure set value corresponding to the 75% THA load according to the target load change rate, and adjust the main steam pressure set value corresponding to the 50% THA load. Step S2: For different target load change rate requirements, determine the critical target value of 50% THA main steam pressure that exactly meets the different target load change rates; Step S3: Fit the critical target value of 50% THA main steam pressure and the corresponding target load rate under different target load rates using the least squares method to construct a function model with the corresponding target load rate as the independent variable and the critical target value of main steam pressure under 50% THA load as the dependent variable. Step S4: Determine the critical target value of 50% THA main steam pressure corresponding to any target variable load rate based on the function model; Step S5: Compare the control effects of the adaptive temperature and pressure control method with those of the conventional temperature and pressure control method using the main steam temperature, reheat steam temperature, comprehensive index of regulation performance, cumulative deviation of key parameters, and real-time standard coal consumption rate index.

[0007] In step S1, the linear relationship between the main steam pressure and the load rate is maintained. The main steam pressure setting value corresponding to 75% THA load is fixed, and the main steam pressure setting value corresponding to 50% THA load is adjusted. Specifically, during the load change process within the 75%~50% THA load range of the coal-fired unit, the main steam pressure always follows the law of linear change with the load rate, and only the slope of the linear relationship is adjusted. For the load reduction process, the initial setting value of the main steam pressure of the coal-fired generator unit is fixed, and the final setting value of the main steam pressure at the end of the load change process is adjusted. For the load increase process, the final setting value of the main steam pressure of the coal-fired generator unit is fixed, and the initial setting value of the main steam pressure at the beginning of the load change process is adjusted.

[0008] In step S2, the method for determining the critical target value of 50%THA main steam pressure is as follows: under the target load change rate, adjust the target value of 50%THA main steam pressure so that the main steam temperature and reheat steam temperature during the load change process do not exceed the set limit control deviation and the maximum deviation of the main steam temperature or reheat steam temperature does not differ from the limit control deviation by more than the set value.

[0009] In step S5, the control effects of the adaptive temperature and pressure control method and the conventional temperature and pressure control method are compared by using the main steam temperature and reheat steam temperature. Specifically, under the same variable load rate, the temperature change curves of the main steam and reheat steam corresponding to different temperature and pressure control methods are compared. By analyzing the temperature fluctuation amplitude, response delay, degree of deviation from the design value, and response time characteristics, the effects of each method on maintaining parameter stability, rapid load response, control accuracy, and regulation efficiency of the coal-fired power generation unit are evaluated, thereby comparing their impact on operational flexibility.

[0010] In step S5, the control effects of the adaptive temperature and pressure control method and the conventional temperature and pressure control method are compared using a comprehensive regulation performance index. Specifically, the comprehensive regulation performance index is a single metric used to quantitatively evaluate the regulation performance of a coal-fired power generation unit during load changes. It comprehensively reflects three key factors: regulation rate, regulation accuracy, and response time. Its value is positively correlated with the overall regulation performance of the coal-fired power generation unit; that is, the larger the comprehensive regulation performance index value, the better the load change regulation performance of the coal-fired power generation unit. The specific calculation formula for the comprehensive regulation performance index is as follows: in, In the formula: This represents a comprehensive indicator of regulatory performance. Indicates the adjustment rate; Indicates adjustment precision; Indicates response time; This represents the standard regulating rate of a coal-fired power generating unit, in MW·min. -1 Take 1.5% of the rated power of the coal-fired power generation unit; This represents the actual regulating rate of a coal-fired power generating unit, in MW·min. -1 ; The actual deviation of the coal-fired power generating unit during regulation is expressed in MW; the allowable deviation is expressed as 1% of the rated active power of the coal-fired power generating unit, in MW. t 2 indicates the time (in seconds) for the coal-fired power generating unit to enter the regulation dead zone, and the dead zone range is taken as 0.5% of the rated power; t 3 indicates the start time of the next load change command, in seconds; This represents the actual power output, in MW, from the time the coal-fired power generating unit enters the regulation dead zone until the next load change command is received. This represents the set power (MW) from the time the coal-fired power generating unit enters the regulation dead zone until the next load change command is received; The actual response time of a coal-fired power generating unit is expressed in seconds; the standard response time is expressed as 60 seconds. t 1 represents the time (in seconds) for the coal-fired power generating unit to adjust out of the response dead zone; t 0 indicates the start time (in seconds) of the given load change command.

[0011] In step S5, the control effects of the adaptive temperature and pressure control method and the conventional temperature and pressure control method are compared using the cumulative deviation of key parameters. Specifically, the cumulative deviation of key parameters is used to quantitatively evaluate the transient operational flexibility of the coal-fired power generation unit during load changes. Its value is negatively correlated with the transient operational flexibility of the coal-fired power generation unit; that is, the smaller the value of the cumulative deviation of key parameters, the better the transient operational flexibility of the coal-fired power generation unit during load changes. The cumulative deviation of key parameters includes the cumulative deviation of main steam pressure, the cumulative deviation of main steam temperature, the cumulative deviation of reheat steam temperature, and the cumulative deviation of coal-fired power generation unit. The formula for calculating the cumulative deviation of main steam pressure is as follows: In the formula: This indicates the cumulative deviation of the main steam pressure, in MPa·s; Indicates the time (in seconds) for the load change process to reach stability. This indicates the actual pressure of the coal-fired power generating unit, in MPa. This indicates the set pressure of the coal-fired power generation unit, in MPa; The formula for calculating the cumulative deviation of main steam temperature is: In the formula: This indicates the cumulative deviation of the main steam temperature, in °C·s; This indicates the actual main steam temperature of the coal-fired power generating unit, in °C. This indicates the set main steam temperature of the coal-fired power generation unit, in °C; The formula for calculating the cumulative deviation of reheat steam temperature is: In the formula: This indicates the cumulative deviation of reheat steam temperature, expressed in °C·s. This indicates the actual reheat steam temperature of the coal-fired power generating unit, in °C. This indicates the set reheat steam temperature for the coal-fired power generation unit, in °C. The formula for calculating the cumulative power deviation of coal-fired power generating units is: In the formula: This represents the cumulative power deviation of coal-fired power generating units, in MJ. This represents the actual power output of a coal-fired power generating unit, in MW. This indicates the set power of the coal-fired power generator set, in MW.

[0012] In step S5, the control effects of the adaptive temperature and pressure control method and the conventional temperature and pressure control method are compared using the real-time standard coal consumption rate index. Specifically, the real-time standard coal consumption rate index is a key parameter used to quantitatively evaluate the energy consumption characteristics of coal-fired power generating units during load changes. Its value is negatively correlated with the energy consumption characteristics of coal-fired power generating units; that is, the smaller the real-time standard coal consumption rate index value, the better the energy consumption characteristics of the coal-fired power generating unit during load changes. The specific calculation formula for the real-time standard coal consumption rate is as follows: In the formula: This represents the real-time standard coal consumption rate during variable load processes, expressed in g·kWh. -1 ; This represents the real-time coal consumption of a coal-fired power generating unit during variable load processes, expressed in kg·s. -1 ; This represents the real-time power generation of a coal-fired power generating unit during a load change process, in kW. This indicates the lower heating value of coal, expressed in kJ·kg⁻¹. -1 29270 represents the lower heating value of standard coal, in kJ·kg⁻¹. -1 .

[0013] Compared with the prior art, the present invention has the following beneficial technical effects: This invention provides an adaptive temperature and pressure control method that considers both the load variation rate and energy consumption characteristics of coal-fired power generating units. It determines the critical target value of the main steam pressure at 50% THA corresponding to the optimal energy consumption under different target load variation rates within the 75%~50% THA load range. Based on this, a function model of the main steam pressure changing with the load variation rate is established using the least squares method, and an adaptive temperature and pressure control method is designed, suitable for dynamic load adjustment processes. The performance improvement effect is evaluated by comparing the operational flexibility of the adaptive temperature and pressure control method with the original conventional temperature and pressure control method. This invention's adaptive temperature and pressure control method can effectively enhance the operational adaptability of the unit and has significant practical application value in promoting the flexible, efficient, and stable operation of coal-fired power generating units. Attached Figure Description

[0014] Figure 1 The critical target value of main steam pressure at 50% THA load for a 330MW coal-fired generating unit during load increase and decrease at different target load change rates within the 75%~50% THA load range. Detailed Implementation

[0015] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0016] The present invention provides an adaptive temperature and pressure control method that takes into account both the load change rate and energy consumption characteristics of coal-fired power generating units, comprising the following steps: Step S1: Study the 75%~50% THA load range of the coal-fired power generation unit, keep the linear relationship between the main steam pressure and the load rate in this load range unchanged, and fix the main steam pressure set value corresponding to the 75% THA load according to the target load change rate, and adjust the main steam pressure set value corresponding to the 50% THA load. Specifically, during the load change process within the 75%~50% THA load range of the coal-fired power unit, the main steam pressure always follows a linear change with the load rate, and only the slope of the linear relationship is adjusted; for the load reduction process, the initial setting value of the main steam pressure of the coal-fired power unit is fixed, and the final setting value of the main steam pressure at the end of the load change process is adjusted; for the load increase process, the final setting value of the main steam pressure of the coal-fired power unit is fixed, and the initial setting value of the main steam pressure at the beginning of the load change process is adjusted.

[0017] Step S2: For different target load change rate requirements, determine the critical target value of 50% THA main steam pressure that exactly meets the different target load change rates; Specifically, the method for determining the critical target value of 50%THA main steam pressure is as follows: Under the target load change rate, adjust the target value of 50%THA main steam pressure so that the main steam temperature and reheat steam temperature during the load change process do not exceed the set limit control deviation, and the maximum deviation of the main steam temperature or reheat steam temperature does not differ from the limit control deviation by more than the set value.

[0018] Step S3: Fit the critical target value of 50% THA main steam pressure and the corresponding target load rate under different target load rates using the least squares method to construct a function model with the corresponding target load rate as the independent variable and the critical target value of main steam pressure under 50% THA load as the dependent variable. Step S4: Determine the critical target value of 50% THA main steam pressure corresponding to any target variable load rate based on the function model; Step S5: Compare the control effects of the adaptive temperature and pressure control method with those of the conventional temperature and pressure control method using the main steam temperature, reheat steam temperature, comprehensive index of regulation performance, cumulative deviation of key parameters, and real-time standard coal consumption rate index.

[0019] Specifically, the control effects of adaptive temperature and pressure control methods versus conventional temperature and pressure control methods are compared using main steam temperature and reheat steam temperature. Under the same variable load rate, the temperature change curves of main steam and reheat steam corresponding to different temperature and pressure control methods are compared. By analyzing the temperature fluctuation amplitude, response delay, degree of deviation from design value, and response time characteristics, the effects of each method on maintaining parameter stability, rapid load response, control accuracy, and regulation efficiency of coal-fired power generating units are evaluated, thereby comparing their impact on operational flexibility.

[0020] Specifically, the control effects of the adaptive temperature and pressure control method and the conventional temperature and pressure control method are compared using a comprehensive regulation performance index. This comprehensive regulation performance index is a single metric used to quantitatively evaluate the regulation performance of a coal-fired power generating unit during load changes. It comprehensively reflects three key factors: regulation rate, regulation accuracy, and response time. Its value is positively correlated with the overall regulation performance of the coal-fired power generating unit; that is, the higher the comprehensive regulation performance index value, the better the load change regulation performance of the coal-fired power generating unit. The specific calculation formula for the comprehensive regulation performance index is as follows: in, In the formula: This represents a comprehensive indicator of regulatory performance. Indicates the adjustment rate; Indicates adjustment precision; Indicates response time; This represents the standard regulating rate of a coal-fired power generating unit, in MW·min. -1 Take 1.5% of the rated power of the coal-fired power generation unit; This represents the actual regulating rate of a coal-fired power generating unit, in MW·min. -1 ; The actual deviation of the coal-fired power generating unit during regulation is expressed in MW; the allowable deviation is expressed as 1% of the rated active power of the coal-fired power generating unit, in MW. t 2 indicates the time (in seconds) for the coal-fired power generating unit to enter the regulation dead zone, and the dead zone range is taken as 0.5% of the rated power; t 3 indicates the start time of the next load change command, in seconds; This represents the actual power output, in MW, from the time the coal-fired power generating unit enters the regulation dead zone until the next load change command is received. This represents the set power (MW) from the time the coal-fired power generating unit enters the regulation dead zone until the next load change command is received; The actual response time of a coal-fired power generating unit is expressed in seconds; the standard response time is expressed as 60 seconds. t 1 represents the time (in seconds) for the coal-fired power generating unit to adjust out of the response dead zone; t 0 indicates the start time (in seconds) of the given load change command.

[0021] Specifically, the control effects of the adaptive temperature and pressure control method and the conventional temperature and pressure control method are compared using the cumulative deviation of key parameters. The cumulative deviation of key parameters is used to quantitatively evaluate the transient operational flexibility of coal-fired power generating units during load changes. Its value is negatively correlated with the transient operational flexibility of coal-fired power generating units; that is, the smaller the value of the cumulative deviation of key parameters, the better the transient operational flexibility of the coal-fired power generating unit during load changes. The cumulative deviation of key parameters includes the cumulative deviation of main steam pressure, the cumulative deviation of main steam temperature, the cumulative deviation of reheat steam temperature, and the cumulative deviation of unit power. The formula for calculating the cumulative deviation of main steam pressure is as follows: In the formula: This indicates the cumulative deviation of the main steam pressure, in MPa·s; Indicates the time (in seconds) for the load change process to reach stability. This indicates the actual pressure of the coal-fired power generating unit, in MPa. This indicates the set pressure of the coal-fired power generation unit, in MPa.

[0022] The formula for calculating the cumulative deviation of main steam temperature is: In the formula: This indicates the cumulative deviation of the main steam temperature, in °C·s; This indicates the actual main steam temperature of the coal-fired power generating unit, in °C. This indicates the set main steam temperature of the coal-fired power generation unit, in °C.

[0023] The formula for calculating the cumulative deviation of reheat steam temperature is: In the formula: This indicates the cumulative deviation of reheat steam temperature, expressed in °C·s. This indicates the actual reheat steam temperature of the coal-fired power generating unit, in °C. This indicates the set reheat steam temperature for the coal-fired power generation unit, in °C.

[0024] The formula for calculating the cumulative power deviation of coal-fired power generating units is: In the formula: This represents the cumulative power deviation of coal-fired power generating units, in MJ. This represents the actual power output of a coal-fired power generating unit, in MW. This indicates the set power of the coal-fired power generator set, in MW.

[0025] Specifically, the control effects of the adaptive temperature and pressure control method and the conventional temperature and pressure control method are compared using the real-time standard coal consumption rate index. The real-time standard coal consumption rate index is a key parameter used to quantitatively evaluate the energy consumption characteristics of coal-fired power generating units during load changes. Its value is negatively correlated with the energy consumption characteristics of coal-fired power generating units; that is, the smaller the real-time standard coal consumption rate index, the better the energy consumption characteristics of the coal-fired power generating unit during load changes. The specific calculation formula for the real-time standard coal consumption rate is as follows: In the formula: This represents the real-time standard coal consumption rate during variable load processes, expressed in g·kWh. -1 ; This represents the real-time coal consumption of a coal-fired power generating unit during variable load processes, expressed in kg·s. -1 ; This represents the real-time power generation of a coal-fired power generating unit during a load change process, in kW. This indicates the lower heating value of coal, expressed in kJ·kg⁻¹. -1 29270 represents the lower heating value of standard coal, in kJ·kg⁻¹. -1 .

[0026] Table 1 details the critical target values ​​of the 50% THA main steam pressure for different target load change rates during the load increase and decrease process of a 330MW coal-fired generating unit within the 75% to 50% THA load range.

[0027] Table 1 Critical target values ​​of main steam pressure for different target load rates Figure 1This paper presents the critical target value of main steam pressure at 50% THA load for a 330MW coal-fired generating unit during load increases and decreases at different target load change rates within the 75% to 50% THA load range. Using the least squares method, a functional relationship between the critical target value of main steam pressure at 50% THA load and the load change rate was established through fitting. Based on this, an adaptive temperature and pressure control method that considers both the load change rate and energy consumption characteristics of the coal-fired generating unit is proposed. According to the data in the charts, the critical target value of main steam pressure at 50% THA load during the load increase process is higher than that during the load decrease process. To ensure that the unit's flexibility meets the requirements, an adaptive temperature and pressure control method is constructed based on the functional relationship between the critical target value of main steam pressure at 50% THA load and the load change rate obtained during the load increase process. By applying this method, the critical target value of the main steam pressure required by the unit to achieve the target load change rate within the 75% to 50% THA load range under 50% THA conditions can be determined. This significantly improves the unit's operational flexibility, increasing the load change rate from 2.0% Pe / min to 5.5% Pe / min, while ensuring the unit's energy consumption characteristics.

Claims

1. An adaptive temperature and pressure control method that takes into account both the variable load rate and energy consumption characteristics of coal-fired power generating units, characterized in that, Includes the following steps: Step S1: Study the 75%~50% THA load range of the coal-fired power generation unit, keep the linear relationship between the main steam pressure and the load rate in this load range unchanged, and fix the main steam pressure set value corresponding to the 75% THA load according to the target load change rate, and adjust the main steam pressure set value corresponding to the 50% THA load. Step S2: For different target load change rate requirements, determine the critical target value of 50% THA main steam pressure that exactly meets the different target load change rates; Step S3: Fit the critical target value of 50% THA main steam pressure and the corresponding target load rate under different target load rates using the least squares method to construct a function model with the corresponding target load rate as the independent variable and the critical target value of main steam pressure under 50% THA load as the dependent variable. Step S4: Determine the critical target value of 50% THA main steam pressure corresponding to any target variable load rate based on the function model; Step S5: Compare the control effects of the adaptive temperature and pressure control method with those of the conventional temperature and pressure control method using the main steam temperature, reheat steam temperature, comprehensive index of regulation performance, cumulative deviation of key parameters, and real-time standard coal consumption rate index.

2. The adaptive temperature and pressure control method for considering both the variable load rate and energy consumption characteristics of coal-fired power generating units according to claim 1, characterized in that, In step S1, the linear relationship between the main steam pressure and the load rate is maintained. The main steam pressure setting value corresponding to 75% THA load is fixed, and the main steam pressure setting value corresponding to 50% THA load is adjusted. Specifically, during the load change process within the 75%~50% THA load range of the coal-fired unit, the main steam pressure always follows the law of linear change with the load rate, and only the slope of the linear relationship is adjusted. For the load reduction process, the initial setting value of the main steam pressure of the coal-fired generator unit is fixed, and the final setting value of the main steam pressure at the end of the load change process is adjusted. For the load increase process, the final setting value of the main steam pressure of the coal-fired generator unit is fixed, and the initial setting value of the main steam pressure at the beginning of the load change process is adjusted.

3. The adaptive temperature and pressure control method for considering both the variable load rate and energy consumption characteristics of coal-fired power generating units according to claim 1, characterized in that, In step S2, the method for determining the critical target value of 50%THA main steam pressure is as follows: under the target load change rate, adjust the target value of 50%THA main steam pressure so that the main steam temperature and reheat steam temperature during the load change process do not exceed the set limit control deviation and the maximum deviation of the main steam temperature or reheat steam temperature does not differ from the limit control deviation by more than the set value.

4. The adaptive temperature and pressure control method for considering both the variable load rate and energy consumption characteristics of coal-fired power generating units according to claim 1, characterized in that, In step S5, the control effects of the adaptive temperature and pressure control method and the conventional temperature and pressure control method are compared by using the main steam temperature and reheat steam temperature. Specifically, under the same variable load rate, the temperature change curves of the main steam and reheat steam corresponding to different temperature and pressure control methods are compared. By analyzing the temperature fluctuation amplitude, response delay, degree of deviation from the design value, and response time characteristics, the effects of each method on maintaining parameter stability, rapid load response, control accuracy, and regulation efficiency of the coal-fired power generation unit are evaluated, thereby comparing their impact on operational flexibility.

5. The adaptive temperature and pressure control method for considering both the variable load rate and energy consumption characteristics of coal-fired power generating units according to claim 1, characterized in that, In step S5, the control effects of the adaptive temperature and pressure control method and the conventional temperature and pressure control method are compared using a comprehensive regulation performance index. The comprehensive regulation performance index is a single metric used to quantitatively evaluate the regulation performance of a coal-fired power generating unit during load changes. It comprehensively reflects three key factors: regulation rate, regulation accuracy, and response time. Its value is positively correlated with the overall regulation performance of the coal-fired power generating unit; that is, the larger the comprehensive regulation performance index value, the better the load change regulation performance of the coal-fired power generating unit. The specific calculation formula for the comprehensive regulation performance index is as follows: in, In the formula: This represents a comprehensive indicator of regulatory performance. Indicates the adjustment rate; Indicates adjustment precision; Indicates response time; This represents the standard regulating rate of a coal-fired power generating unit, in MW·min. -1 Take 1.5% of the rated power of the coal-fired power generation unit; This represents the actual regulating rate of a coal-fired power generating unit, in MW·min. -1 ; The actual deviation of the coal-fired power generating unit during regulation is expressed in MW; the allowable deviation is expressed as 1% of the rated active power of the coal-fired power generating unit, in MW. t 2 indicates the time (in seconds) for the coal-fired power generating unit to enter the regulation dead zone, and the dead zone range is taken as 0.5% of the rated power; t 3 indicates the start time of the next load change command, in seconds; This represents the actual power output, in MW, from the time the coal-fired power generating unit enters the regulation dead zone until the next load change command is received. This represents the set power (MW) from the time the coal-fired power generating unit enters the regulation dead zone until the next load change command is received; The actual response time of a coal-fired power generating unit is expressed in seconds; the standard response time is expressed as 60 seconds. t 1 represents the time (in seconds) for the coal-fired power generating unit to adjust out of the response dead zone; t 0 indicates the start time (in seconds) of the given load change command.

6. The adaptive temperature and pressure control method for considering both the variable load rate and energy consumption characteristics of coal-fired power generating units according to claim 1, characterized in that, In step S5, the control effects of the adaptive temperature and pressure control method and the conventional temperature and pressure control method are compared using the cumulative deviation of key parameters. The cumulative deviation of key parameters is used to quantitatively evaluate the transient operational flexibility of the coal-fired power generation unit during load changes. Its value is negatively correlated with the transient operational flexibility of the coal-fired power generation unit; that is, the smaller the value of the cumulative deviation of key parameters, the better the transient operational flexibility of the coal-fired power generation unit during load changes. The cumulative deviation of key parameters includes the cumulative deviation of main steam pressure, the cumulative deviation of main steam temperature, the cumulative deviation of reheat steam temperature, and the cumulative deviation of coal-fired power generation unit. The formula for calculating the cumulative deviation of main steam pressure is as follows: In the formula: This indicates the cumulative deviation of the main steam pressure, in MPa·s; Indicates the time (in seconds) for the load change process to reach stability. This indicates the actual pressure of the coal-fired power generating unit, in MPa. This indicates the set pressure of the coal-fired power generation unit, in MPa; The formula for calculating the cumulative deviation of main steam temperature is: In the formula: This indicates the cumulative deviation of the main steam temperature, in °C·s; This indicates the actual main steam temperature of the coal-fired power generating unit, in °C. This indicates the set main steam temperature of the coal-fired power generation unit, in °C; The formula for calculating the cumulative deviation of reheat steam temperature is: In the formula: This indicates the cumulative deviation of reheat steam temperature, expressed in °C·s. This indicates the actual reheat steam temperature of the coal-fired power generating unit, in °C. This indicates the set reheat steam temperature for the coal-fired power generation unit, in °C. The formula for calculating the cumulative power deviation of coal-fired power generating units is: In the formula: This represents the cumulative power deviation of coal-fired power generating units, in MJ. This represents the actual power output of a coal-fired power generating unit, in MW. This indicates the set power of the coal-fired power generator set, in MW.

7. The adaptive temperature and pressure control method for considering both the variable load rate and energy consumption characteristics of coal-fired power generating units according to claim 1, characterized in that, In step S5, the control effects of the adaptive temperature and pressure control method and the conventional temperature and pressure control method are compared using the real-time standard coal consumption rate index. The real-time standard coal consumption rate index is a key parameter used to quantitatively evaluate the energy consumption characteristics of coal-fired power generating units during load changes. Its value is negatively correlated with the energy consumption characteristics of coal-fired power generating units; that is, the smaller the value of the real-time standard coal consumption rate index, the better the energy consumption characteristics of the coal-fired power generating unit during load changes. The specific calculation formula for the real-time standard coal consumption rate is as follows: In the formula: This represents the real-time standard coal consumption rate during variable load processes, expressed in g·kWh. -1 ; This represents the real-time coal consumption of a coal-fired power generating unit during variable load processes, expressed in kg·s. -1 ; This represents the real-time power generation of a coal-fired power generating unit during a load change process, in kW. This indicates the lower heating value of coal, expressed in kJ·kg⁻¹. -1 29270 represents the lower heating value of standard coal, in kJ·kg⁻¹. -1 .

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