A method for improving the peak shaving capacity of a thermal power unit based on a new heat storage tank of a Tesla valve

Abstract

The application discloses a method for improving the peak regulation capacity of a thermal power generating unit based on a Tesla valve new type heat storage tank. The method can compensate for insufficient heat supply or the remaining part of heat supply by the Tesla valve new type heat storage tank to maintain the stability of the heat load, expand the electric heat operation interval, increase the electric output regulation range of the unit, and thus improve the peak regulation capacity of the unit. The Tesla valve new type heat storage tank can increase the number of Tesla valve stages, reduce the turbulence loss rate, reduce the energy loss degree in the Tesla valve, and increase the maximum heat storage capacity during the peak load period, that is, the total increase of the peak regulation capacity within a day.

Description

Technical Field

[0001] This invention belongs to the field of clean energy consumption technology, specifically relating to a method for improving the peak-shaving capacity of thermal power units based on a novel heat storage tank with a Tesla valve. Background Technology

[0002] my country has become the world's largest wind power market; however, the problem of wind curtailment is becoming increasingly serious, causing huge economic losses and energy waste. "Wind-heat conflict" is one of the main causes of my country's wind curtailment problem.

[0003] The "wind-heat conflict" arises because wind power exhibits typical anti-peak-shaving characteristics, characterized by fluctuating daytime output within a certain range and gradually increasing output at night, as well as seasonal output patterns with the highest average output in winter and the lowest in summer. This significantly increases the system's peak-shaving demand and difficulty. Furthermore, in my country's "Three Norths" region, where winter heating seasons are generally long, combined heat and power (CHP) units, capable of producing both electricity and heat, have been vigorously developed due to their high efficiency and environmental friendliness. They constitute a large proportion of the power supply structure, and heating load is crucial to people's lives. As the primary heat source, CHP units must prioritize meeting the heating load, resulting in a "heat-driven power generation" operating constraint. This leads to a decrease in the system's peak-shaving capacity during the winter heating season, or even the inability to achieve peak-shaving. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide a method for improving the peak-shaving capacity of thermal power units based on a new type of Tesla valve thermal storage tank. By configuring a new type of Tesla valve thermal storage tank, the electric heating operating range is expanded, the maximum heat storage capacity during peak load periods is increased, and the absorption capacity of wind power is improved.

[0005] The technical solution adopted in this invention is as follows:

[0006] This invention provides a method for improving the peak-shaving capacity of thermal power units based on a novel Tesla valve-based thermal storage tank, which is implemented according to the following steps:

[0007] Step S1: Establish a model relating the peak-shaving capacity increment of the unit after configuring the new type of thermal storage tank with Tesla valves to the maximum storage and release power of the thermal storage device;

[0008] Step S2: Calculate the electro-thermal characteristics before and after assembling the new Tesla valve thermal storage tank to obtain the range of improved peak-shaving capacity of the unit;

[0009] Step S3: Based on the electro-thermal characteristics of the new Tesla valve thermal storage tank, obtain the relationship between the maximum heat storage capacity and the number of Tesla valve stages;

[0010] Step S4: Substitute the relationship between the maximum heat storage capacity and the number of Tesla valve stages into the relationship model obtained in step S1 to obtain the relationship between the number of Tesla valve stages and the unit's peak-shaving capacity increment.

[0011] Step S5: Assemble the new type of thermal storage tank with Tesla valve of the corresponding level according to the requirements of the unit's peak-shaving capacity and peak-shaving range.

[0012] Furthermore, step S1, establishing a model relating the peak-shaving capacity increment of the unit after configuring the new type of thermal storage tank with a Tesla valve, to the maximum storage and release power of the thermal storage device, includes:

[0013] Based on the maximum heat storage capacity Q of the thermal storage tank during the waist load period S,F The maximum heat storage capacity Q of the thermal storage tank during off-peak hours D,L The magnitude of the peak-shaving capacity increment ΔC is determined by the value of the peak-shaving capacity increment.

[0014] Furthermore, step S2 calculates the electro-thermal characteristics of the new thermal storage tank after assembling the Tesla valve, and obtains the range of improved peak-shaving capacity of the unit, including:

[0015] Based on the formulas for the electrothermal characteristics before and after configuring thermal storage, obtain the electrothermal characteristic curves and compare the changes in the peak-shaving capacity range.

[0016] Furthermore, in step S3, the specific relationship between the maximum heat storage capacity and the number of Tesla valve stages is obtained by optimizing the electro-thermal characteristics of the multi-stage Tesla valve, including:

[0017] Research on Tesla valves includes electrothermal characteristic formulas, continuity of multi-stage Tesla valves, control equations for momentum and energy, and standard... The relevant equations and formulas of the turbulence model are derived.

[0018] Furthermore, the relationship between the number of Tesla valve stages and the increase in the unit's peak-shaving capacity in step S4 is as follows:

[0019] ;

[0020] The beneficial effects of this invention are:

[0021] This invention discloses a method for improving the peak-shaving capacity of thermal power units based on a novel heat storage tank with Tesla valves. It mainly addresses the problem of wind curtailment caused by "wind-heat conflict". By configuring a novel heat storage tank with multi-stage Tesla valves, the thermal power unit's insufficient or surplus heat supply is compensated for by the novel heat storage tank with Tesla valves to maintain the stability of the heat load. This expands the electric heating operating range and increases the adjustment range of the unit's electric output, thereby improving the unit's peak-shaving capacity.

[0022] By configuring a Tesla valve thermal storage tank and increasing the number of stages, the turbulence loss rate is reduced, the energy loss inside the Tesla valve decreases, the maximum heat storage capacity during peak load periods increases, the total daily peak-shaving capacity increases, and the wind power absorption level is improved. Attached Figure Description

[0023] Figure 1 This is a schematic diagram illustrating the improved peak-shaving capacity of thermal power units equipped with new thermal storage tanks.

[0024] Figure 2 This is a diagram showing the impact of the maximum heat release capacity of the thermal storage device on the increase in peak-shaving capacity of the combined heat and power unit.

[0025] Figure 3 This is a diagram showing the impact of the novel thermal storage device with a Tesla valve configured in this invention on the electric-thermal operation zone of a combined heat and power unit. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] This invention discloses a method for improving the peak-shaving capacity of thermal power units based on a novel Tesla valve-based thermal storage tank, which is implemented according to the following steps:

[0028] Step S1: Establish a model relating the peak-shaving capacity increment of the unit after configuring the new type of thermal storage tank with Tesla valves to the maximum storage and release power of the thermal storage device;

[0029] Step S2: Calculate the electro-thermal characteristics before and after assembling the new Tesla valve thermal storage tank to obtain the range of improved peak-shaving capacity of the unit;

[0030] Step S3: Based on the electro-thermal characteristics of the new Tesla valve thermal storage tank, obtain the relationship between the maximum heat storage capacity and the number of Tesla valve stages;

[0031] Step S4: Substitute the relationship between the maximum heat storage capacity and the number of Tesla valve stages into the relationship model obtained in step S1 to obtain the relationship between the number of Tesla valve stages and the unit's peak-shaving capacity increment.

[0032] Step S5: Assemble the new type of thermal storage tank with Tesla valve of the corresponding level according to the requirements of the unit's peak-shaving capacity and peak-shaving range.

[0033] This invention provides a method for enhancing the peak-shaving capacity of thermal power units based on a novel Tesla valve-based thermal storage tank. The Tesla valve-based thermal storage tank compensates for insufficient or surplus heating in thermal power units, maintaining stable heat load and expanding the electric heating operating range. This increases the adjustment range of the unit's electrical output, thereby improving the unit's peak-shaving capacity. Furthermore, by increasing the number of Tesla valve stages, the turbulence loss rate is reduced, the energy loss within the Tesla valve is decreased, and the maximum heat storage capacity during peak load periods is increased, resulting in a greater daily increase in peak-shaving capacity.

[0034] Specifically, step S1 includes:

[0035] Based on the maximum heat storage capacity Q of the thermal storage tank during the waist load period S,F The maximum heat storage capacity Q of the thermal storage tank during off-peak hours D,L The magnitude of the peak-shaving capacity increment ΔC is determined by the value of the peak-shaving capacity increment.

[0036] When the thermal storage tank has no stored heat, adhering to the principle of prioritizing the use of new energy sources for heating, the heating temperature of the primary heat source is adjusted first to fully utilize its adjustment capacity. If there is still excess heat power, the logic sequence of the thermal storage tank is adjusted to obtain the configuration result with the smallest possible volume, minimizing the volume of the new type of thermal storage tank equipped with Tesla valves and achieving complete utilization of new energy. After the charging process is completed, to prevent heat loss during the static process of the thermal storage tank, the heat stored in the tank is released first, and the heating power of the primary heat source is coordinated and controlled to meet the heat load demand in real time.

[0037] Since the peak-shaving capacity coefficient during off-peak hours is usually greater than that during peak hours, and the duration of the off-peak period of the unit's daily electrical load is approximately equal to the duration of the peak-valley period of the unit's daily electrical load, the wind power acceptance space obtained by using the stored heat during off-peak hours is greater than that obtained during peak hours. Therefore, when the heat storage capacity of the Tesla valve new type of thermal storage tank is limited, it is prioritized to compensate for the off-peak period. When the heat storage during mid-load is insufficient, the Tesla valve new type of thermal storage tank adopts the method of storing heat during peak load periods and releasing heat during off-peak periods to increase the wind power acceptance space provided by the unit.

[0038] Since the wind power acceptance space obtained by using heat during off-peak hours is greater than that obtained during peak hours, when heat storage is limited, priority should be given to compensating for off-peak hours. When the heat storage during mid-load is insufficient, heat storage can be used during peak load hours and heat release during off-peak hours to increase the wind power acceptance space provided by the unit. Therefore, when the amount of heat storage during mid-load hours and off-peak hours is different, the increase in peak-shaving capacity will be different. Therefore, according to Q... S,F and Q D,L The size of these two factors determines the increase in peak-shaving capacity of the new Tesla valve thermal storage tank.

[0039] when hour:

[0040] (1);

[0041] in, This refers to the increased peak-shaving capacity during off-peak periods; The increased peak-shaving capacity during peak and valley periods; c m This is the peak-shaving capacity coefficient during off-peak hours; The duration of the off-peak period of the unit's electrical load within a day; c is the maximum amount of heat that the thermal storage tank can store during peak load periods; v1 This refers to the peak adjustment capacity coefficient at the peak. The duration of peak and off-peak periods of the unit's electrical load within a day;

[0042] The maximum heat storage capacity Q of the new thermal storage tank during waist load period S,F for:

[0043] (2);

[0044] in, Set the maximum heat storage capacity for the thermal storage tank; This represents the maximum steam extraction heating capacity of the steam turbine. The heat load level at time t; After configuring thermal storage, its minimum heating power is shifted to the left by a certain amount;

[0045] Maximum heat storage capacity Q during peak load period S,P for:

[0046] (3);

[0047] Maximum heat storage capacity Q during off-peak hours D,L for:

[0048] (4);

[0049] in, This is the lowest point in the range of electrothermal characteristics; The range within which the electrothermal characteristics increase after configuring thermal storage;

[0050] when hour:

[0051] (5);

[0052] Based on the above formulas (1) to (5), the peak-shaving capacity increment ΔC can be obtained:

[0053] (6);

[0054] Specifically, step S2 includes:

[0055] Based on the formulas for the electrothermal characteristics before and after configuring thermal storage, obtain the electrothermal characteristic curves and compare the changes in the peak-shaving capacity range.

[0056] Specifically, the electro-thermal characteristics before configuring thermal storage:

[0057] (7);

[0058] in, Minimum electrical power; Maximum electrical power; For heating power; C v C represents the decrease in power generation per unit of heat supplied when the steam intake remains constant; v1 This is the value corresponding to the maximum electrical output; C v2 This represents the value corresponding to the minimum electric output; K is a constant.

[0059] The electro-thermal characteristics after configuring thermal storage:

[0060] ; (8)

[0062] Specifically, in step S3,

[0063] Will Defined as positive heat absorption, as mentioned above, the total daily increase in peak-shaving capacity is mainly determined by the maximum heat storage capacity during peak load periods. Therefore, this study is based on multi-stage Tesla valves.

[0064] (9);

[0065] in, The heat load level at time t;

[0066] (10);

[0067] in, Fuel consumption It has a low calorific value as fuel.

[0068] (11);

[0069] in, This is the initial amount of fuel. For fuel loss, This represents the amount of fuel used. Substituting (11) into (10) yields:

[0070] (12);

[0071] The hydrogen flow within the multi-stage Tesla valve is a compressible fluid. The governing equations for continuity, momentum, and energy during the numerical simulation are as follows:

[0072] (13);

[0073] (14);

[0074] (15);

[0075] in, For density, For speed, Where is viscosity and P is pressure. For Prandtl numbers, and For specific heat, The symbol for Kronecker. It is viscous stress.

[0076] standard The relevant equations for the turbulence model are:

[0077] (16);

[0078] (17);

[0079] The formula for fuel loss is:

[0080] (18);

[0081] Where M is a positive coefficient, Let be the turbulent loss rate. The formula for the turbulent loss rate is:

[0082] (19);

[0083] Where N is a negative coefficient. Let T be the number of Tesla valve stages, and T be the fixed loss. Substituting (18) and (19) into (12) yields:

[0084] (20);

[0085] Substituting (20) into (9), we get:

[0086] (twenty one);

[0087] Among them, Q 初 Q is the initial amount of fuel. 损 Q represents fuel loss. 用 For fuel consumption, M is a positive coefficient, N is a negative coefficient, and Z is a negative coefficient.级数 Let T be the number of Tesla valve stages, and T be the fixed loss.

[0088] According to equation (21), when the thermal storage tank is equipped with a Tesla valve, and as the number of Tesla valve stages increases, the turbulent loss rate gradually decreases, the energy loss inside the Tesla valve decreases, and the maximum heat storage capacity during peak load periods increases. Thus, the new thermal storage tank releases heat through the Tesla valve, its overall maximum heating power increases, the range of power generation adjustment of the turbine increases, and its electrothermal characteristics are optimized.

[0089] Example

[0090] This paper analyzes the effect of configuring thermal storage on improving peak-shaving capacity of typical 300MW-class heating units in northern my country. It assumes that the units only handle heating load, and since the daily variation in heating load is small, it is assumed that the heat load power remains constant throughout the day. Specific peak-shaving capacities are shown in Table 1.

[0091] Table 1

[0092] It can be seen that the configuration of thermal storage expands the electric and thermal operating range of the 300MW unit. Moreover, the thermal storage tank with multi-stage Tesla valves further expands the range of electric and thermal range compared with ordinary thermal storage tanks. Corresponding to a given heat load level, the power output adjustment range of the 300MW unit in a single time period is increased.

[0093] like Figure 2 As shown, with the continuous increase in the thermal storage capacity and heat release capacity of the thermal storage device, when the configured thermal storage capacity reaches 897MW and the heat release capacity reaches 259.8MW, the peak-shaving capacity increment reaches a constant maximum value of 67.3MW, which is 22.4% of the rated capacity. At this time, the total peak-shaving capacity of the unit is 114.5MW, accounting for 38.2% of the rated capacity, which is about 2.4 times higher than the 47.2MW before thermal storage.

[0094] Through the above methods, this invention provides a method for enhancing the peak-shaving capacity of thermal power units based on a novel Tesla valve thermal storage tank. Addressing the wind curtailment problem caused by the "wind-heat conflict" in my country, this method improves the peak-shaving capacity of thermal power units by equipping them with a novel thermal storage tank, thereby increasing the absorption rate of wind power. A comparison of the electrothermal operating range and peak-shaving capacity of thermal power units before and after configuring the novel Tesla valve thermal storage tank shows that the power output adjustment range of the thermal power units is increased, and the peak-shaving capacity is significantly improved. The method for enhancing the peak-shaving capacity of thermal power units using the novel Tesla valve thermal storage tank involves the Tesla valve thermal storage tank compensating for insufficient heating or storing excess heat to maintain stable heat load when the thermal power unit's heating is insufficient or the excess heat is supplied, thus expanding the electrothermal operating range. The novel Tesla valve thermal storage tank increases the number of Tesla valve stages, reducing the turbulent loss rate and the energy loss within the Tesla valve, increasing the maximum heat storage capacity during peak load periods, thereby improving the unit's peak-shaving capacity.

Claims

1. A method for improving the peak-shaving capacity of thermal power units based on a novel Tesla valve-based thermal storage tank, characterized in that, Follow these steps: Step S1: Establish a model relating the peak-shaving capacity increment of the unit after configuring the new type of thermal storage tank with Tesla valves to the maximum storage and release power of the thermal storage device; Step S2: Calculate the electro-thermal characteristics before and after assembling the new Tesla valve thermal storage tank to obtain the range of improved peak-shaving capacity of the unit; Step S3: Based on the electro-thermal characteristics of the new Tesla valve thermal storage tank, obtain the relationship between the maximum heat storage capacity and the number of Tesla valve stages; Step S4: Substitute the relationship between the maximum heat storage capacity and the number of Tesla valve stages into the relationship model obtained in step S1 to obtain the relationship between the number of Tesla valve stages and the unit's peak-shaving capacity increment. Step S5: Assemble the new type of thermal storage tank with Tesla valve of the corresponding level according to the requirements of the unit's peak-shaving capacity and peak-shaving range. The step S1, establishing a model relating the peak-shaving capacity increment of the unit after configuring the new type of Tesla valve thermal storage tank to the maximum storage and release power of the thermal storage device, includes: Based on the maximum heat storage capacity Q of the thermal storage tank during the waist load period S,F The maximum heat storage capacity Q of the thermal storage tank during off-peak hours D,L The magnitude of the peak-shaving capacity increment ΔC is determined by: ； in, Set the maximum heat storage capacity for the thermal storage tank; The range within which the electrothermal characteristics increase after configuring thermal storage; In step S3, the specific relationship between the maximum heat storage capacity and the number of Tesla valve stages is obtained by optimizing the electro-thermal characteristics of the multi-stage Tesla valve, including: Research on Tesla valves includes electrothermal characteristic formulas, continuity of multi-stage Tesla valves, control equations for momentum and energy, and standard... The relevant equations and formulas of the turbulence model are derived. The relationship between the number of Tesla valve stages and the increment of the unit's peak-shaving capacity in step S4 is as follows: ； Among them, Q 初 Q is the initial amount of fuel. 损 Q represents fuel loss. 用 Where M represents fuel consumption, N represents a positive coefficient, Z represents the number of Tesla valve stages, and T represents fixed losses.

2. The method for improving the peak-shaving capacity of thermal power units based on a novel Tesla valve-based thermal storage tank according to claim 1, characterized in that, Step S2 calculates the electro-thermal characteristics of the new thermal storage tank after assembling the Tesla valve, and obtains the range of improved peak-shaving capacity of the unit, including: Based on the formulas for the electrothermal characteristics before and after configuring thermal storage, electrothermal characteristic curves are obtained, and the changes in peak-shaving capacity range are compared.

3. The method for improving the peak-shaving capacity of thermal power units based on a novel Tesla valve-based thermal storage tank according to claim 2, characterized in that, The formula for the electrothermal characteristics before configuring thermal storage is: ； in, Minimum electrical power; Maximum electrical power; For heating power; C v C represents the decrease in power generation per unit of heat supplied when the steam intake remains constant; v1 This is the value corresponding to the maximum electrical output; C v2 This represents the value corresponding to the minimum electric output; K is a constant.

4. The method for improving the peak-shaving capacity of thermal power units based on a novel Tesla valve-based thermal storage tank according to claim 3, characterized in that, The formula for the electrothermal characteristics after configuring thermal storage is: 。

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