Closed steam Rankine cycle power system configuration optimization and variable load control method based on heat storage quantity feedforward

Abstract

The invention discloses a closed steam Rankine cycle power system configuration optimization and variable load control method based on heat storage feed-forward, and the closed steam Rankine cycle power system configuration optimization comprises the steps: adding a water supply bypass valve and a water storage tank in a system; an inlet water temperature sensor and an outlet steam temperature sensor are arranged at an inlet and an outlet of a boiler respectively, a fuel flow meter is arranged at an outlet of a fuel regulating valve, a water flow meter is arranged at an outlet of a main water supply valve, a power sensor is arranged at a rotating shaft of a turbine, and the water supply flow regulating capacity and the dynamic stability capacity of the system are improved through system configuration optimization. A system variable load control strategy after configuration optimization is further provided, a water supply bypass valve is adopted to control the system operation load, a fuel regulating valve is adopted to control the boiler outlet steam temperature, and the deviation between the steady-state heat storage capacity and the real-time heat storage capacity of the boiler is used as a fuel regulating valve auxiliary control signal. The system effectively solves the problems of overshoot of the steam temperature of the boiler outlet and low variable load rate of the system, and improves the safety and the rapid variable load capacity.

Description

Technical Field

[0001] The present invention belongs to the field of control and automation technology, and particularly relates to a closed steam Rankine power system configuration optimization and variable load control method based on heat storage feedforward. Background Art

[0002] In the field of small power systems, a steam turbine directly drives a water pump to save space, a design that is particularly common in small steam power cycle systems. This structure allows for a compact internal system layout, but it also brings new challenges.

[0003] Because the steam turbine and water pump are directly connected, the system's mass flow control is tightly coupled to the turbine's power. This coupling makes it difficult to control the water flow rate during load changes in small steam power cycles, leading to system shutdowns caused by overheating of the steam outlet or a rapid decrease in water flow due to turbine power. Therefore, optimizing the load-variable control process and accelerating control response time have become key issues that need to be addressed in the operation and development of these power systems, requiring technological innovation to address these challenges. Summary of the Invention

[0004] In order to solve the problems existing in the above-mentioned prior art and realize the configuration optimization and control strategy optimization of the closed steam Rankine cycle power system, the purpose of the present invention is to provide a closed steam Rankine cycle power system configuration optimization and variable load control method based on heat storage feedforward. The present invention proposes a new closed steam Rankine cycle power system configuration with an additional feedwater bypass regulating valve and a water storage tank. On this basis, a variable load control method for the system after configuration optimization is proposed, in which the feedwater bypass valve is used to control the system load change, the fuel regulating valve is used to control the boiler outlet steam temperature change, and the real-time heat storage change of the system is calculated by arranging measuring points. The fuel regulating valve is assisted in controlling the fuel regulating valve through the deviation between the steady-state heat storage and the real-time heat storage to realize the optimal control of the boiler outlet steam temperature.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A closed steam Rankine cycle power system configuration optimization and variable load control method based on heat storage feedforward, including closed steam Rankine cycle power system configuration optimization and variable load control method of the system after configuration optimization;

[0007] The configuration optimization of the closed steam Rankine cycle power system includes adding a feedwater bypass valve 7 and a water storage tank 8 to the system, setting an inlet water temperature sensor T1 and an outlet steam temperature sensor T2 at the inlet and outlet of the boiler 2 respectively, setting a fuel flow meter at the outlet of the fuel regulating valve 1, setting a water flow meter at the outlet of the main feedwater valve 6, and setting a power sensor P1 at the rotating shaft of the turbine 3 to obtain system operating parameters to support the implementation of the control strategy; the optimized closed steam Rankine cycle power system includes a fuel regulating valve 1, a boiler 2, a steam turbine 3, a condenser 4, a water storage tank 8 and a water pump 5 connected in sequence, and the outlet of the water pump 5 is divided into two paths, one of which is connected to the water storage tank 8 through the feedwater bypass valve 7, and the other is connected to the boiler 2 through the main feedwater valve 6; the feedwater bypass valve 7 is used to divert water from the outlet of the water pump 5 to the water storage tank 8, so as to increase the feedwater flow control range and solve the water flow control problem of the steam turbine water pump coupling system;

[0008] The variable load control method of the system after configuration optimization is as follows:

[0009] Step 1, data collection: The inlet water temperature sensor T1 and the outlet steam temperature sensor T2 at the inlet and outlet of boiler 2 respectively measure the boiler inlet water temperature and boiler outlet steam temperature. The fuel flow rate Q1 at the outlet of fuel regulating valve 1 is measured by a fuel flow meter, and the water flow rate Q2 at the outlet of the main feedwater valve is measured by a water flow meter. The turbine work power at the rotating shaft of turbine 3 is measured by power sensor P1, which is the system operating load.

[0010] Step 2, the specific control strategy of the boiler outlet steam temperature and the turbine power during the load change process: according to the size of the system load change rate, the temperature control instruction and the load control instruction change accordingly. The faster the load change rate, the faster the temperature control instruction and the load control instruction change, and the corresponding set temperature and set load change. Among them, the deviation between the set load and the current system operating load is used as the input signal of the PI controller. The PI controller acts on the feed water bypass valve 7 adjustment mechanism with the output signal to adjust the opening of the feed water bypass valve 7 to realize the automatic control of the load during the system load change process. During the load change process, in addition to controlling the turbine work power, that is, the system operating load, the boiler outlet steam temperature must also be controlled within the set range. For temperature control, the deviation between the set temperature and the real-time temperature, that is, the measured boiler outlet steam temperature, is used as the input signal of the PI controller. After being processed by the PI controller, a control signal for controlling the opening change of the fuel regulating valve 1 is obtained. In addition, according to the difference between the boiler outlet steam temperature and the boiler inlet water temperature and the size of the water flow Q2 in the system, the water side heat absorption power Q is calculated using formula (1): xr ;

[0011] Qxr=Q2C p (T out -T in) Formula (1)

[0012] Where: Q2 - water flow, unit is kg / s; C p ——Specific heat capacity of water, in J / (kg·K); T in ——Boiler inlet water temperature, in °C; T out ——Boiler outlet steam temperature, in °C;

[0013] The heat storage capacity Xr is the time integral of the difference between the heat release power of the fuel and the heat absorption power of the water side. When the heat release power of the fuel is equal to the heat absorption power of the water side, the system reaches thermal equilibrium, the heat storage capacity no longer changes, and the system reaches a stable operating state.

[0014] After calculating the heat absorption power of the water side in the system, use formula (2) to calculate the heat release power Q of the system fuel under the corresponding fuel flow rate. rl ;

[0015] Q rl =m rl q formula (2)

[0016] Where: q is the heat released per 1 kg of fuel, in kJ / kg; m rl is the fuel flow rate, in kg / s;

[0017] Fuel heat release power Q rl and water side heat absorption power Q xr The difference is then integrated to obtain the current real-time heat storage capacity Xr of the system, as shown in formula (3);

[0018] Xr=∫(Q rl -Q xr ) Formula (3)

[0019] The steady-state heat storage of the system with variable load is a fixed value. The calculation method of the steady-state heat storage is based on the temperature difference of the boiler metal wall before and after the load change and the specific heat capacity of the metal wall. Formula (4) is used to calculate the steady-state heat storage of the boiler metal wall.

[0020] Xr wt =C pm (T b -T a )m Formula (4)

[0021] Where: Xr wt ——Steady-state heat storage capacity, in kJ; C p,m ——Specific heat capacity of metal, in J / (kg·K); T b ——Metal wall temperature before load change, in °C; T a ——The temperature of the metal wall after load change; m——Total mass of the metal wall, in kg;

[0022] The deviation between the steady-state heat storage of the system after load change and the real-time heat storage during the current load change process is used as the input signal of the PI controller. The output signal of the PI controller is used as the heat storage feedforward control signal. Together with the output signal of the PI controller with the temperature deviation as input, the opening of the fuel regulating valve 1 is controlled to achieve the control of the boiler outlet steam temperature during the load change process.

[0023] In the temperature control strategy, heat storage feedforward control can improve the situation where the boiler outlet steam temperature has a long response time and a large overshoot caused by large changes in heat storage during variable load.

[0024] In order to reduce the restriction of the water pump speed on the water flow regulation in the system under the current operating load of the system and improve the water flow regulation capability during the load change process, a water supply bypass valve 7 with adjustable opening is added after the condenser 4 to regulate the water flow in the system. Compared with the regulation of the main water supply valve 6, the outlet of the water supply bypass valve 7 is located in the water storage tank 8, and the pressure in the water storage tank is in the low-pressure zone. The inlet of the main water supply valve 6 is the water pump outlet with high pressure. The pressure difference between the outlet of the water pump 5 and the inlet of the water supply bypass valve 7 is large. By increasing the opening of the water supply bypass valve 7, the water flow is diverted to the water storage tank 8 in the low-pressure zone, thereby increasing the water flow regulation capability of the system and reducing the coupling relationship between the system operating load and the water flow in the system.

[0025] Adding a water storage tank 8 at the condenser outlet can provide a stable low-pressure environment for the small closed steam Rankine cycle power system and buffer the changes in the condensate temperature of the condenser 4, further improving the dynamic disturbance characteristics of the system and reducing the fluctuation of the steam temperature at the boiler outlet. The water storage tank 8 is also connected to the feed water bypass valve 7, and can also maintain the relative stability of the water level and pressure when the feed water bypass valve 7 operates quickly.

[0026] A fuel flow meter, a water flow meter, and a boiler inlet water temperature sensor T1 are newly added. The fuel heat release power is calculated from the fuel flow rate, and the water heat absorption power in the boiler is calculated from the water flow rate, the boiler inlet water temperature, and the boiler outlet steam temperature. The difference between the fuel heat release power and the water heat absorption power in the boiler is integrated to obtain the real-time heat storage change of the boiler, thereby realizing real-time monitoring and calculation of the boiler heat storage.

[0027] The fuel regulating valve 1 is used to control the change of boiler outlet steam temperature, and the feedwater bypass valve 7 is used to control the turbine power. The control method is PI control, which can speed up the system's load change response speed and eliminate steady-state errors.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] 1. In order to improve the restriction of the system operating load on the mass flow rate in the system during the system load change process and weaken the strong coupling relationship between the water pump speed and the system water flow, the present invention adds a water supply bypass valve 7 with adjustable opening between the water pump 5 outlet and the water storage tank 8. The low-pressure area provided in the water storage tank can divert the high-pressure water at the water pump outlet to the low-pressure area water storage tank 8, thereby improving the water flow regulation ability of the system during the load change process and improving the problems of small regulation range and poor regulation accuracy of the water flow in the original system main water supply valve regulating the system.

[0030] 2. In order to improve the system's adaptability to external environmental disturbances, the present invention adds a water storage tank 8, which can buffer the changes in the water temperature at the condenser 5 outlet, reduce the impact of the changes in the condenser outlet water temperature on the boiler inlet water temperature during the load change process, slow down the speed of change of the boiler inlet water temperature, and improve the stability of the boiler outlet steam temperature during the load change process.

[0031] 3. In order to solve the problem that the heat storage changes greatly during the load change process of a small steam power system, the steam temperature adjustment time at the steam boiler outlet is long, and it cannot meet the needs of rapid load change, the present invention proposes a system load change control strategy based on heat storage feedforward on the basis of system configuration optimization. This strategy can significantly accelerate the boiler outlet steam temperature adjustment time and the system load change rate. Compared with the control method of controlling the boiler outlet steam temperature without using heat storage feedforward, the steam outlet temperature adjustment time can be accelerated. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a schematic diagram of the optimized closed steam Rankine cycle power system configuration of the present invention.

[0033] Figure 2 Schematic diagram of the control strategy after system configuration optimization.

[0034] Figure 3 The figure shows the comparison of load increase control results before and after optimization.

[0035] Figure 4 The figure shows the comparison of load control results before and after optimization. DETAILED DESCRIPTION

[0036] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] like Figure 1As shown, the present invention optimizes the configuration of a closed steam Rankine cycle power steam Rankine cycle system. In this closed steam Rankine cycle system, the water pump is driven by the turbine, resulting in tightly coupled system parameters. Furthermore, the boiler's high thermal inertia slows the system's load change rate, making it difficult to meet the requirements for rapid and flexible operation. This invention proposes an optimization solution that adds a feedwater bypass valve and a water storage tank to improve the system's feedwater flow regulation and dynamic stability. The configuration optimization of the closed steam Rankine cycle power system includes adding a feedwater bypass valve 7 and a water tank 8 to the system, setting an inlet water temperature sensor T1 and an outlet steam temperature sensor T2 at the inlet and outlet of the boiler 2 respectively, setting a fuel flow meter at the outlet of the fuel regulating valve 1, setting a water flow meter at the outlet of the main feedwater valve 6, and setting a power sensor P1 at the rotating shaft of the turbine 3 to obtain system operating parameters to support the implementation of the control strategy; the optimized closed steam Rankine cycle power system includes a fuel regulating valve 1, a boiler 2, a turbine 3, a condenser 4, a water tank 8 and a water pump 5 connected in sequence, and the outlet of the water pump 5 is divided into two paths, one is connected to the water tank 8 through the feedwater bypass valve 7, and the other is connected to the boiler 2 through the main feedwater valve 6; the feedwater bypass valve 7 is used to divert the water at the outlet of the water pump 5 to the water tank 8 to increase the feedwater flow control amplitude and solve the water flow control problem of the turbine water pump coupling system; on this basis, the variable load control method of the system after configuration optimization is obtained, as shown in FIG. Figure 2 As shown in Figure 2, the specific implementation steps of the system variable load control method after configuration optimization are as follows:

[0038] Step 1, data collection: The inlet water temperature sensor T1 and the outlet steam temperature sensor T2 at the inlet and outlet of boiler 2 respectively measure the boiler inlet water temperature and boiler outlet steam temperature. The fuel flow rate Q1 at the outlet of fuel regulating valve 1 is measured by a fuel flow meter, and the water flow rate Q2 at the outlet of the main feedwater valve is measured by a water flow meter. The turbine work power at the rotating shaft of turbine 3 is measured by power sensor P1, which is the system operating load.

[0039] Step 2, specific control strategy for boiler outlet steam temperature and turbine power during load variation: according to the size of the system load variation rate, the temperature control instruction and the load control instruction change accordingly. The faster the load variation rate, the faster the temperature control instruction and the load control instruction change, and the corresponding set temperature and set load change. The deviation between the set load and the current system operating load is used as the input signal of the PI controller (the PI controller is a proportional-integral controller, the proportional link can quickly respond to the deviation, and the integral link can eliminate the static deviation). The PI controller acts on the output signal to the water supply bypass valve 7 regulating mechanism to adjust the opening of the water supply bypass valve 7 to achieve automatic control of the load during the system load variation process.

[0040] During the load change process, in addition to controlling the turbine power, i.e., the system operating load, the boiler outlet steam temperature must also be controlled within the set range. For temperature control, the deviation between the set temperature and the real-time temperature, i.e., the measured boiler outlet steam temperature, is used as the input signal of the PI controller. After being processed by the PI controller, the control signal for controlling the opening change of the fuel regulating valve 1 is obtained. In addition, according to the difference between the boiler outlet steam temperature and the boiler inlet water temperature and the size of the water flow Q2 in the system, the water side heat absorption power Q is calculated using formula (1): xr ;

[0041] Qxr=Q2C p (T out -T in ) Formula (1)

[0042] Where: Q2 - water flow, unit is kg / s; C p ——Specific heat capacity of water, in J / (kg·K); T in ——Boiler inlet water temperature, in °C; T out ——Boiler outlet steam temperature, unit is kg / s.

[0043] The heat storage capacity Xr is the time integral of the difference between the heat release power of the fuel and the heat absorption power of the water side. When the heat release power of the fuel is equal to the heat absorption power of the water side, the system reaches thermal equilibrium, the heat storage capacity no longer changes, and the system reaches a stable operating state.

[0044] After calculating the heat absorption power on the water side of the system, use formula (2) to calculate the heat release power Qrl of the fuel in the system at the corresponding fuel flow rate.

[0045] Q rl =m rl q formula (2)

[0046] Where: q is the heat released per 1 kg of fuel, in kJ / kg; m rl is the fuel flow rate, in kg / s;

[0047] Fuel heat release power Q rl and water side heat absorption power Q xr The difference is then integrated to obtain the current real-time heat storage capacity Xr of the system, as shown in formula (3);

[0048] Xr=∫(Qrl-Qxr) Formula (3)

[0049] The steady-state heat storage of the system with variable load is a fixed value. The steady-state heat storage is calculated based on the temperature difference of the boiler metal wall before and after the load change and the specific heat capacity of the metal wall. Formula (4) is used to calculate the steady-state heat storage of the boiler metal wall.

[0050] Xrwt =C pm (T b -T a )m Formula (4)

[0051] Where: Xr wt ——Steady-state heat storage capacity, in kJ; Cp——metal specific heat capacity, in J / (kg·K); T b ——Metal wall temperature before load change, in °C; T a ——Temperature of the metal wall after load change; m——Mass of the metal wall, in kg.

[0052] The relationship between the input signal e(t) and the output signal u(t) of the PI controller (proportional-integral controller) is shown in formula (5):

[0053]

[0054] The deviation between the steady-state heat storage of the system after load variation and the real-time heat storage during the current load variation process is used as the input signal of the PI controller. The output signal of the PI controller is used as the heat storage feedforward control signal. Together with the output signal of the PI controller with the temperature deviation as input, the opening of the fuel regulating valve 1 is controlled to achieve the control of the boiler outlet steam temperature during the load variation process.

[0055] Depend on Figure 3 As shown in the figure, after the configuration is optimized, the system adopts the above-mentioned variable load control strategy. When the load is increased, when the load rate increases from 15% to 100%, compared with the feedforward process without increasing the heat storage capacity, the load rate fluctuation of the system variable load process is significantly reduced, and the load adjustment time of the variable load process is accelerated from 150s to about 50s.

[0056] Depend on Figure 4 As shown in the figure, after the configuration is optimized, the system adopts the above-mentioned variable load control strategy. When the load is reduced, the adjustment time required for the boiler outlet steam temperature to increase from about 710°C to about 800°C is reduced from 200s to about 25s. Compared with the feedforward process without adding heat storage, the steam outlet temperature overshoot is reduced by 50°C.

[0057] Depend on Figure 3 , Figure 4 The comparison of the system variable load control results after configuration optimization proves that the configuration optimization system and corresponding control strategy proposed in this invention can improve the load adjustment time and boiler outlet steam temperature adjustment time during the variable load process, and reduce the boiler outlet steam temperature overshoot.

Claims

1. A closed steam Rankine cycle power system configuration optimization and variable load control method based on heat storage feedforward, characterized in that: Including closed steam Rankine cycle power system configuration optimization and variable load control method of the system after configuration optimization; The configuration optimization of the closed steam Rankine cycle power system includes adding a feed water bypass valve (7) and a water storage tank (8) in the system, setting an inlet water temperature sensor (T1) and an outlet steam temperature sensor (T2) at the inlet and outlet of the boiler (2), setting a fuel flow meter at the outlet of the fuel regulating valve (1), setting a water flow meter at the outlet of the main feed water valve (6), and setting a power sensor (P1) at the rotating shaft of the turbine (3) to obtain system operating parameters to support the implementation of the control strategy; after optimization, the closed steam Rankine cycle power system is The Ken cycle power system comprises a fuel regulating valve (1), a boiler (2), a steam turbine (3), a condenser (4), a water storage tank (8) and a water pump (5) which are connected in sequence. The outlet of the water pump (5) is divided into two paths, one path is connected to the water storage tank (8) through a feed water bypass valve (7), and the other path is connected to the boiler (2) through a main feed water valve (6); the feed water bypass valve (7) is used to divert water at the outlet of the water pump (5) into the water storage tank (8) to increase the feed water flow control range and solve the water flow control problem of the steam turbine water pump coupling system; The variable load control method of the system after configuration optimization is as follows: Step 1, data collection: the inlet water temperature sensor (T1) and the outlet steam temperature sensor (T2) at the inlet and outlet of the boiler (2) respectively measure the boiler inlet water temperature and the boiler outlet steam temperature, the fuel flow rate Q1 at the outlet of the fuel regulating valve (1) is measured by a fuel flow meter, the water flow rate Q2 at the outlet of the main feed water valve is measured by a water flow meter, and the turbine work power at the rotating shaft of the turbine (3) is measured by a power sensor (P1), which is the system operating load; Step 2, the specific control strategy of the boiler outlet steam temperature and the turbine power during the load change process: according to the size of the system load change rate, the temperature control instruction and the load control instruction change accordingly. The faster the load change rate, the faster the temperature control instruction and the load control instruction change speed, and the corresponding set temperature and set load change. Among them, the deviation between the set load and the current system operating load is used as the input signal of the PI controller. The PI controller acts on the feed water bypass valve (7) regulating mechanism with the output signal to adjust the opening of the feed water bypass valve (7) to realize the automatic control of the load during the system load change process. During the load change process, in addition to controlling the turbine power, i.e., the system operating load, the boiler outlet steam temperature must be controlled within the set range. For temperature control, the deviation between the set temperature and the real-time temperature, i.e., the measured boiler outlet steam temperature, is used as the input signal of the PI controller. After being processed by the PI controller, a control signal for controlling the opening change of the fuel regulating valve (1) is obtained. In addition, according to the difference between the boiler outlet steam temperature and the boiler inlet water temperature and the size of the water flow Q2 in the system, the water side heat absorption power Q is calculated using formula (1). xr ; Qxr=Q2C p (T out -T in ) Formula (1) Where: Q2 - water flow, unit is kg / s; C p ——Specific heat capacity of water, in J / (kg·K); T in ——Boiler inlet water temperature, in °C; T out ——Boiler outlet steam temperature, in °C; The heat storage capacity Xr is the time integral of the difference between the heat release power of the fuel and the heat absorption power of the water side. When the heat release power of the fuel is equal to the heat absorption power of the water side, the system reaches thermal equilibrium, the heat storage capacity no longer changes, and the system reaches a stable operating state. After calculating the heat absorption power of the water side in the system, use formula (2) to calculate the heat release power Q of the system fuel under the corresponding fuel flow rate. rl ; Q rl =m rl q formula (2) Where: q is the heat released per 1 kg of fuel, in kJ / kg; m rl is the fuel flow rate, in kg / s; Fuel heat release power Q rl and water side heat absorption power Q xr The difference is then integrated to obtain the current real-time heat storage capacity Xr of the system, as shown in formula (3); Xr=∫(Q rl -Q xr ) Formula (3) The steady-state heat storage of the system with variable load is a fixed value. The calculation method of the steady-state heat storage is based on the temperature difference of the boiler metal wall before and after the load change and the specific heat capacity of the metal wall. Formula (4) is used to calculate the steady-state heat storage of the boiler metal wall. Xr wt =C pm (T b -T a )m Formula (4) Where: Xr wt ——Steady-state heat storage capacity, in kJ; C p,m ——Specific heat capacity of metal, in J / (kg·K); T b ——Metal wall temperature before load change, in °C; T a ——The temperature of the metal wall after load change; m——Total mass of the metal wall, in kg; The deviation between the steady-state heat storage of the system after load change and the real-time heat storage during the current load change process is used as the input signal of the PI controller, and the output signal of the PI controller is used as the heat storage feedforward control signal. Together with the output signal of the PI controller with the temperature deviation as input, the opening of the fuel regulating valve (1) is controlled to achieve the control of the boiler outlet steam temperature during the load change process; In the temperature control strategy, heat storage feedforward control can improve the situation where the boiler outlet steam temperature has a long response time and a large overshoot caused by large changes in heat storage during variable load.

2. The closed steam Rankine cycle power system configuration optimization and variable load control method based on heat storage feedforward according to claim 1 is characterized by: In order to reduce the restriction of the water pump speed on the water flow regulation in the system under the current operating load of the system and improve the water flow regulation capability in the process of variable load, a feed water bypass valve (7) with adjustable opening is newly added after the condenser (4) to regulate the water flow in the system. Compared with the regulation of the main feed water valve (6), the outlet of the feed water bypass valve (7) is located in the water storage tank (8), the pressure in the water storage tank is in the low pressure area, the inlet of the main feed water valve (6) is the water pump outlet, the pressure is high, and the pressure difference between the outlet of the water pump (5) and the inlet of the feed water bypass valve (7) is large. By increasing the opening of the feed water bypass valve (7), the water flow is diverted to the water storage tank (8) in the low pressure area, thereby increasing the water flow regulation capability of the system and reducing the coupling relationship between the system operating load and the water flow in the system.

3. The closed steam Rankine cycle power system configuration optimization and variable load control method based on heat storage feedforward according to claim 1 is characterized by: Adding a water storage tank (8) at the outlet of the condenser can provide a stable low-pressure environment for the small closed steam Rankine cycle power system and buffer the change of the condensed water temperature of the condenser (4), further improving the dynamic disturbance characteristics of the system and reducing the fluctuation of the steam temperature at the boiler outlet. The water storage tank (8) is also connected to the feed water bypass valve (7), and can also maintain the relative stability of the water level and pressure when the feed water bypass valve (7) is quickly operated.

4. The closed steam Rankine cycle power system configuration optimization and variable load control method based on heat storage feedforward according to claim 1 is characterized by: A fuel flow meter, a water flow meter, and a boiler inlet water temperature sensor (T1) are newly added. The fuel heat release power is calculated from the fuel flow rate, and the water heat absorption power in the boiler is calculated from the water flow rate, the boiler inlet water temperature, and the boiler outlet steam temperature. The difference between the fuel heat release power and the water heat absorption power in the boiler is integrated to obtain the real-time heat storage change of the boiler, thereby realizing real-time monitoring and calculation of the boiler heat storage capacity.

5. The closed steam Rankine cycle power system configuration optimization and variable load control method based on heat storage feedforward according to claim 1 is characterized by: A fuel regulating valve (1) is used to control the change of boiler outlet steam temperature, and a feedwater bypass valve (7) is used to control the turbine power. The control method is PI control, which can accelerate the system load change response speed and eliminate steady-state errors.

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