Frequency modulation power supply, power system and dispatching method

Abstract

The application provides a frequency modulation power supply, a power system and a dispatching method. The frequency modulation power supply comprises a signal dispatching device, a coal-fired generator set and an internal combustion engine generator set. A first output end of the signal dispatching device is connected to the coal-fired generator set, and a second output end of the signal dispatching device is connected to the internal combustion engine generator set. The signal dispatching device is used for distributing a dispatching signal to the coal-fired generator set and the internal combustion engine generator set. The application can improve the response speed during frequency modulation operation.

Description

Technical Field

[0001] This application relates to the field of power generation technology, and in particular to a frequency-regulating power supply, power system and dispatching method. Background Technology

[0002] Wind and solar power are gradually becoming the main power sources. However, due to their significant intermittency and volatility, and with the continuous increase in the demand for frequency regulation in the power system, the power system needs to respond to power fluctuations from wind and solar power with greater amplitude, faster speed, and higher precision to ensure power balance and achieve large-scale renewable energy utilization. Currently, the power system uses coal-fired power units as frequency regulation power sources. However, coal-fired power units have equipment with significant inertia, such as boilers and turbines, resulting in a regulation rate of only 1%-2% of rated output per minute, leading to a low response speed during frequency regulation operation. Summary of the Invention

[0003] This application provides a frequency modulation power supply, a power system, and a dispatching method to solve the problem of low response speed during frequency modulation operation.

[0004] In a first aspect, embodiments of this application provide a frequency modulation power supply, including signal scheduling equipment, a coal-fired generator set, and an internal combustion engine generator set, wherein:

[0005] The first output terminal of the signal dispatching device is connected to the coal-fired generator set, and the second output terminal of the signal dispatching device is connected to the internal combustion engine generator set;

[0006] The signal dispatching device is used to distribute dispatching signals to the coal-fired generator set and the internal combustion engine generator set.

[0007] Secondly, embodiments of this application also provide a power system, the power system including the frequency modulation power supply disclosed in the first aspect of embodiments of this application.

[0008] Thirdly, embodiments of this application also provide a scheduling method applied to the frequency modulation power supply disclosed in the first aspect of embodiments of this application, the method comprising:

[0009] Acquire dispatch signals, as well as the first output of the coal-fired generator set and the second output of the internal combustion engine generator set;

[0010] A first dispatch signal for the coal-fired generator set is determined based on the first output, and a second dispatch signal for the internal combustion engine generator set is determined based on the second output, wherein the dispatch signal includes the first dispatch signal and the second dispatch signal;

[0011] The first dispatch signal is sent to the coal-fired generator set, and the second dispatch signal is sent to the internal combustion engine generator set.

[0012] In this embodiment, the coal-fired generator set and the internal combustion engine generator set are coupled together as a frequency-regulating power source, and the scheduling signal is distributed to the coal-fired generator set and the internal combustion engine generator set through the signal scheduling device. This fully utilizes the frequency regulation capability of the coal-fired generator set and the high frequency regulation rate of the internal combustion engine generator set, thereby improving the response speed during frequency regulation operation. Attached Figure Description

[0013] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is one of the structural schematic diagrams of a frequency modulation power supply provided in the embodiments of this application;

[0015] Figure 2 This is a second schematic diagram of the structure of a frequency modulation power supply provided in the embodiments of this application;

[0016] Figure 3 This is a flowchart illustrating a scheduling method provided in an embodiment of this application;

[0017] Figure 4 This is a schematic diagram of the frequency regulation rate of an internal combustion engine provided in an embodiment of this application;

[0018] Figure 5 This is a schematic diagram of automatic power generation control signal distribution provided in an embodiment of this application. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] Please see Figure 1 , Figure 1 This is one of the structural schematic diagrams of a frequency modulation power supply provided in the embodiments of this application, such as... Figure 1 As shown, it includes signal dispatching equipment 10, a coal-fired generator set 20, and an internal combustion engine generator set 30, wherein:

[0021] The first output terminal of the signal dispatching device 10 is connected to the coal-fired generator set 20, and the second output terminal of the signal dispatching device 10 is connected to the internal combustion engine generator set 30.

[0022] The signal dispatching device 10 is used to distribute dispatching signals to the coal-fired generator set 20 and the internal combustion engine generator set 30.

[0023] Due to the randomness of power system load and power output from sources such as wind and solar power, in order to respond to power fluctuations in wind and solar power and ensure the stable operation and power quality of the power system, it is necessary to adjust the power output of the coal-fired generator set 20 and the internal combustion engine generator set 30 through the aforementioned frequency regulation power source. The coal-fired generator set 20 has a large single-unit capacity, which can meet the needs of large-scale frequency regulation. However, due to the presence of equipment with large inertia such as boilers and turbines, its response speed during frequency regulation is relatively low. The internal combustion engine generator set 30, on the other hand, converts the heat energy released by fuel combustion inside the machine into electrical energy, and has the characteristics of fast regulation speed and high regulation accuracy. This application couples the coal-fired generator set 20 and the internal combustion engine generator set 30 for frequency regulation, which can improve the frequency regulation response speed while ensuring that the coal-fired generator set meets the needs of large-scale frequency regulation.

[0024] The signal dispatching device 10 can determine the frequency regulation change corresponding to the dispatching signal based on the acquired Automatic Generation Control (AGC) signal, the current output of the coal-fired generator set 20, and the current output of the internal combustion engine generator set 30. For example, the current output of the coal-fired generator set 20 is denoted as P. G1 The current power output of the aforementioned internal combustion engine generator set 30 is denoted as P. G2 The EMS (Energy Management System) sends an AGC signal to the aforementioned signal dispatching device 10. The electrical load corresponding to the AGC signal is denoted as P. AGG Therefore, the frequency modulation change ΔP corresponding to the above scheduling signal is -P. AGG -P G1 -P G2 Furthermore, the sum of the frequency modulation change corresponding to the signal allocated to the coal-fired generator set 20 and the frequency modulation change corresponding to the signal allocated to the internal combustion engine generator set 30 is the frequency modulation change corresponding to the dispatch signal. The coal-fired generator set 20 and the internal combustion engine generator set 30 respond to their respective allocated frequency modulation signals.

[0025] In this embodiment, the coal-fired generator set 20 and the internal combustion engine generator set 30 are coupled as frequency-regulating power sources, and the signal scheduling device 10 distributes the scheduling signal to the coal-fired generator set 20 and the internal combustion engine generator set 30. This fully utilizes the frequency regulation capability of the coal-fired generator set and the high frequency regulation rate of the internal combustion engine generator set, thereby improving the response speed during frequency regulation operation.

[0026] Optionally, such as Figure 2 As shown, the coal-fired power generation unit 20 includes a boiler 21, a steam turbine 22, a condenser 23, a condensate pump 24, a low-pressure heater 25, a deaerator 26, a feedwater pump 27, a high-pressure heater 28, and a first generator 29, wherein:

[0027] The first output terminal of the signal dispatching device 10 is connected to the first input terminal of the boiler 21 and the first input terminal of the steam turbine 22;

[0028] The output end of the boiler 21 is connected to the second input end of the steam turbine 22, the first output end of the steam turbine 22 is connected to the input end of the condenser 23, the output end of the condenser 23 is connected to the input end of the condensate pump 24, the output end of the condensate pump 24 is connected to the input end of the low-pressure heater 25, the output end of the low-pressure heater 25 is connected to the input end of the deaerator 26, the output end of the deaerator 26 is connected to the input end of the feedwater pump 27, the output end of the feedwater pump 27 is connected to the input end of the high-pressure heater 28, and the output end of the high-pressure heater 28 is connected to the second input end of the boiler 21.

[0029] The second output terminal of the steam turbine 22 is connected to the input terminal of the first generator 29.

[0030] In this embodiment, the coal-fired power generation unit has a large single-unit scale, which can meet the needs of large-scale frequency regulation.

[0031] Optionally, such as Figure 2 As shown, the internal combustion engine generator set 30 includes an internal combustion engine 31 and a second generator 32. The second output terminal of the signal dispatching device 10 is connected to the input terminal of the internal combustion engine 31, and the first output terminal of the internal combustion engine 31 is connected to the input terminal of the second generator 32.

[0032] The internal combustion engine 31 can use a variety of fuels, such as natural gas and LNG (liquefied natural gas), and has strong fuel compatibility.

[0033] In this embodiment, the internal combustion engine generator set 30 uses fuel to burn inside the internal combustion engine 31 and converts the heat energy output by the internal combustion engine 31 into electrical energy through the second generator, which can quickly adjust the power output.

[0034] Optionally, such as Figure 2 As shown, the internal combustion engine generator set 30 also includes a cylinder liner 33, a heat exchanger 34, and an exhaust system 35, wherein:

[0035] The second output terminal of the internal combustion engine 31 is connected to the first input terminal of the cylinder liner 33, the first output terminal of the cylinder liner 33 is connected to the input terminal of the internal combustion engine 31, and the first input terminal of the cylinder liner 33 is connected to the first output terminal of the cylinder liner 33.

[0036] The third output end of the internal combustion engine 31 is connected to the first input end of the heat exchanger 34, the first output end of the heat exchanger 34 is connected to the input end of the exhaust device 35, and the first input end of the heat exchanger 34 is connected to the first output end of the heat exchanger 34.

[0037] The output end of the condenser pump 24 is connected to the second input end of the cylinder liner 33, the second output end of the cylinder liner 33 is connected to the second input end of the heat exchanger 34, the second output end of the heat exchanger 34 is connected to the input end of the deaerator 26, and the second input end of the cylinder liner 33 is connected to the second output end of the cylinder liner 33, and the second input end of the heat exchanger 34 is connected to the second output end of the heat exchanger 34.

[0038] The condensate output from the condenser pump 24 can be partially heated by the low-pressure heater 25 and then fed into the deaerator 26. The other part can be heated by the waste heat of the flue gas generated by the internal combustion engine 31 through the cylinder liner 33 and the heat exchanger 34 before being fed into the deaerator 26. Taking a certain type of internal combustion engine as an example, the exhaust temperature of the internal combustion engine is 350°C to 450°C, which accounts for about 40% to 50% of the total usable waste heat of the internal combustion engine. It is a usable medium- and high-temperature heat source. In this way, through the thermal coupling between the coal-fired generator set 20 and the internal combustion engine generator set, the waste heat of the flue gas generated by the internal combustion engine can be utilized efficiently and stably.

[0039] Specifically, the heat exchanger 34 can be a flue gas-water heat exchanger. For example, the first input end of the heat exchanger 34 can be used to input the high-temperature flue gas generated by the combustion of the internal combustion engine 31, and the second input end of the heat exchanger 34 can be used to input the condensate generated by the coal-fired generator set 20. Through heat exchange in the flue gas-water heat exchanger, the high-temperature flue gas can be used to heat the condensate, forming a parallel heating system with the low-pressure heater 25, thereby improving the waste heat utilization rate of the internal combustion engine generator set and reducing the cost of low-pressure heating.

[0040] In addition, the purchase and installation cost of the flue gas water heat exchanger is lower than that of current waste heat boilers and other solutions, thereby improving the economic efficiency of the frequency-regulating power supply. At the same time, this application takes advantage of the large capacity of the deaerator and the fact that it generally has a capacity margin of about 20% of the main steam flow per hour. The cylinder liner 33 and the heat exchanger 34 are configured at the input end of the deaerator 26 as the waste heat coupling utilization system of the internal combustion engine generator set 30. This ensures that the heating feedwater of the parallel system of the low-pressure heater and the flue gas water heat exchanger will not have a large fluctuation effect on the thermal stability of the coal-fired generator set 20.

[0041] The exhaust device 35 can be used to exhaust the waste heat exhaust gas discharged from the internal combustion engine after heat exchange. For example, the exhaust gas can be directly discharged through the exhaust device 35 or filtered and discharged into the atmosphere.

[0042] In this embodiment, the utilization rate of waste heat from the flue gas generated by the internal combustion engine 31 can be improved, reducing energy waste, while avoiding the impact of adding an extra waste heat boiler on the frequency regulation performance of the internal combustion engine generator set.

[0043] Optionally, such as Figure 2 As shown, the frequency-modulated power supply also includes a first valve 40, a second valve 50, and a third valve 60. The output end of the condenser pump 24 is connected to the input end of the first valve 40, the first output end of the first valve 40 is connected to the input end of the low-pressure heater 25, the second output end of the first valve 40 is connected to the input end of the second valve 50, and the output end of the second valve 50 is connected to the second input end of the cylinder liner 33.

[0044] The second output end of the heat exchanger 34 is connected to the input end of the third valve 60, and the output end of the third valve 60 is connected to the input end of the deaerator 26.

[0045] Specifically, the first valve 40 can be a three-way valve, including one inlet and two outlets. The inlet can correspond to the input end of the first valve 40, and the two outlets can correspond to the first output end and the second output end of the first valve 40, respectively.

[0046] In this embodiment, the condensate is diverted through the first valve 40, making full use of the waste heat from the flue gas of the internal combustion engine generator set 30, reducing resource waste, and lowering the cost required for the low-pressure heater 25 to heat the condensate, thereby improving the economic efficiency of the frequency regulation power supply operation.

[0047] This application embodiment also provides a power system, which includes the above-described frequency-modulated power supply.

[0048] Please see Figure 3 This application also provides a flowchart of a scheduling method, as shown in the embodiments below. Figure 3 As shown, this is applied to the embodiments of this application. Figure 1 and Figure 2 The frequency modulation power supply of this embodiment includes the following steps:

[0049] Step 301: Obtain the dispatch signal, as well as the first output of the coal-fired generator set and the second output of the internal combustion engine generator set.

[0050] During actual operation of the power plant, the output of different types of units varies with the AGC signal. Due to the randomness of the power system's load and the output of power sources such as wind power and photovoltaics, the frequency regulation demand of the power system is also a random process. Therefore, the timing of the AGC signal and the required adjustment range have significant uncertainties, and the actual output of coal-fired generator units and internal combustion engine generator units will also change accordingly.

[0051] Specifically, the aforementioned scheduling signal can be determined based on the acquired AGC signal. For example, at a certain moment, the EMS sends an AGC signal to the aforementioned frequency-regulating power source. The aforementioned first output and the aforementioned second output can be the actual output of the coal-fired generator set and the actual output of the internal combustion engine generator set, respectively, recorded by the power plant distributed control system (DCS) at the time the aforementioned AGC signal is issued. Thus, the power generation output that the aforementioned frequency-regulating power source needs to adjust can be determined based on the aforementioned AGC signal, the aforementioned first output, and the aforementioned second output, that is, the frequency regulation change corresponding to the aforementioned frequency regulation signal can be determined.

[0052] Step 302: Determine the first dispatch signal of the coal-fired generator set and the second dispatch signal of the internal combustion engine generator set based on the first output and the second output, wherein the dispatch signal includes the first dispatch signal and the second dispatch signal.

[0053] Step 303: Send the first dispatch signal to the coal-fired generator set and the second dispatch signal to the internal combustion engine generator set.

[0054] In this embodiment, a first scheduling signal for the coal-fired generator set is determined based on the first output, and a second scheduling signal for the internal combustion engine generator set is determined based on the second output. The first scheduling signal is sent to the coal-fired generator set, and the second scheduling signal is sent to the internal combustion engine generator set. The coal-fired generator set and the internal combustion engine generator set can adjust their actual output according to the scheduling signals to improve the frequency regulation response rate of the frequency regulation power supply.

[0055] Optionally, the step 302, which involves determining the first dispatch signal for the coal-fired power generator set and the second dispatch signal for the internal combustion engine power generator set based on the first output and the second output, may include:

[0056] The first power generation efficiency and the first frequency regulation rate of the coal-fired generator set are obtained, as well as the second power generation efficiency and the second frequency regulation rate of the internal combustion engine generator set.

[0057] The third dispatch signal for the coal-fired power generator set and the fourth dispatch signal for the internal combustion engine power generator set are determined based on the first power generation efficiency, the first frequency regulation rate, the second power generation efficiency, the second frequency regulation rate, the first output, and the second output.

[0058] Obtain the profit parameters corresponding to the frequency modulation power supply, and optimize and adjust the third scheduling signal and the fourth scheduling signal based on the profit parameters to determine the first scheduling signal and the second scheduling signal.

[0059] The power generation efficiency and frequency regulation rate of the aforementioned coal-fired power generating units can be changed in real time. For example, the power generation efficiency curves and frequency regulation rate curves of the aforementioned coal-fired power generating units and internal combustion engine power generating units can be obtained in advance. The actual output, power generation efficiency, and frequency regulation rate of the current coal-fired power generating units and internal combustion engine power generating units can be determined based on the timing of the frequency regulation signal. Furthermore, the increase or decrease in output allocated to the coal-fired power generating units and internal combustion engine power generating units can be determined to improve profit parameters. Specifically, taking the internal combustion engine frequency regulation rate curve as an example... Figure 4 A schematic diagram of the frequency modulation rate of an internal combustion engine provided in an embodiment of this application is shown below. Figure 4 As shown, the frequency regulation rate of an internal combustion engine is related to the unit load rate as a nonlinear function. A nonlinear convex optimization model can be used to determine the frequency regulation rate corresponding to the current operating point of the internal combustion engine.

[0060] The aforementioned profit parameters can be determined by various parameters, such as the revenue generated and corresponding costs incurred by the frequency-regulating power generation of the generator set during actual operation, including power generation revenue parameters, frequency regulation revenue parameters, fuel cost parameters, and operation and maintenance cost parameters.

[0061] In this embodiment, the third dispatch signal of the coal-fired generator set and the fourth dispatch signal of the internal combustion engine generator set are determined by the first power generation efficiency, the first frequency regulation rate, the second power generation efficiency, the second frequency regulation rate, the first output, and the second output. The third dispatch signal and the fourth dispatch signal are optimized and adjusted based on the profit parameter, thereby maximizing the profit parameter while increasing the frequency regulation rate.

[0062] For ease of understanding, the following example is provided:

[0063] Because the timing of AGC frequency modulation commands and the required adjustment range are both significantly uncertain, this application proposes an optimized scheduling method for the allocation of frequency modulation signals among different types of generating units, based on the frequency modulation characteristics of different units and collaborative control optimization. This scheduling method can specifically include the following processes:

[0064] Generate FM scenes: Obtain multiple AGC commands, and based on the statistical characteristics of the AGC commands, generate an AGC sequence whose amplitude follows a normal distribution and whose command interval follows a Poisson distribution. Generate N FM scenes in sequence based on the AGC sequence.

[0065] Establish an AGC signal allocation and scheduling model: When the internal combustion engine coupled coal-fired power plant receives the AGC command, it will obtain the power generation efficiency and frequency regulation rate curves of the internal combustion engine and coal-fired power unit at the operating point of the unit recorded in the distributed control system, and establish an allocation and scheduling model.

[0066] Taking the internal combustion engine as an example, the frequency regulation rate of the internal combustion engine is as follows: Figure 4 As shown, by Figure 4 It is known that the frequency regulation rate of the internal combustion engine is related to the unit load rate as a nonlinear function. Using a nonlinear convex optimization model as the above allocation and scheduling model, the frequency regulation signals allocated to the internal combustion engine generator set and the coal-fired generator set are calculated, which are the values ​​of increasing or decreasing the output of the internal combustion engine generator set and the coal-fired generator set respectively.

[0067] Obtain the objective function for optimizing the above allocation and scheduling model: Max(R) grid +RC fuel -C O&M The optimized model was then used to determine the frequency modulation signals actually allocated to the internal combustion engine generator sets and the coal-fired generator sets.

[0068] Among them, maximizing the profit of an internal combustion engine coupled with a coal-fired power plant under a single AGC frequency regulation command is taken as the ultimate optimization objective. The annual operating revenue of the power plant includes power generation revenue R. grid The expenses consist of two parts: frequency regulation revenue (R) and expenditures including fuel costs (C). fuel and maintenance costs C O&M .

[0069] Electricity revenue R grid It can be obtained through the following calculation method:

[0070] R grid =R g_grid +R c_grid ;

[0071] R g_grid =ΔT g_j ×Pg(M g ,P g_opera )×P grid ;

[0072] R c_grid =ΔT c_j ×Pc(M c ,P c_opera )×P grid ;

[0073] Among them, P grid Indicates the feed-in tariff, ΔT g_j and ΔT c_j Pg(M) represents the response time of the internal combustion engine and the coal-fired power unit, respectively. g ,P g_opera Pc(M) represents the output power of an internal combustion engine unit per unit time. c ,P c_opera The two numbers represent the output per unit time of a coal-fired power unit, respectively, and are related to the number of units M. g and M c and running point P g_opera and P c_opera related;

[0074] Obtaining the frequency modulation revenue R-quantization model may include the following process:

[0075] Frequency regulation power sources combining internal combustion engine generator sets and coal-fired generator sets generate revenue by providing frequency regulation services to the power system. This revenue depends on two factors: frequency regulation mileage and frequency regulation performance. Frequency regulation mileage refers to the absolute value of the difference between the actual output value of the generator set after receiving an AGC control command and the output value at the time the command was issued. The frequency regulation mileage D of the generator set within a billing cycle is the sum of the adjustments made in response to AGC control commands during that period.

[0076]

[0077] Where, p k p represents the actual output value of the unit after receiving the AGC control command. k-1 This indicates the output value of the group when the AGC command is issued;

[0078] The frequency regulation performance K is determined by three indicators: regulation rate K1, regulation accuracy K2, and response time K3. Among them, the regulation rate K1 refers to the rate at which the unit responds to AGC commands, which measures the ratio of the actual regulation rate of the unit to the standard rate that it should achieve.

[0079] The adjustment rate of the i-th unit during the j-th adjustment It can be obtained through the following calculation method:

[0080]

[0081] Among them, v i,j P represents the adjustment rate (unit: MW / minute) of unit i during the j-th adjustment. Ei,j T represents the power output (unit: MW) at the end of the unit's response to the AGC command. Ei,j P indicates the end time (in minutes). Si,j This indicates the unit's output (unit: MW) when it begins responding to AGC commands, T Si,j Indicates the starting time (in minutes); v N,i This indicates the standard AGC (Automatic Control) rate of the units within the system (unit: MW / minute).

[0082] The adjustment accuracy K2 refers to the difference between the actual output and the AGC command value after the unit response stabilizes. It represents the adjustment accuracy of the i-th unit during the j-th adjustment. It can be obtained through the following calculation method:

[0083]

[0084] Where, ΔP i,j P represents the deviation (unit: MW) of the j-th adjustment of the i-th unit. i,j (i) represents the actual output of the unit during this time period, P i,j This indicates the AGC command value within that time period.

[0085] The response time K3 refers to the time ΔT required for the unit to reliably cross the regulation dead zone in the same direction as the regulation, based on the original output point, after the dispatching system issues an instruction.

[0086] From the above, the regulation rate K1, regulation accuracy K2, and response time K3 can be calculated, thereby obtaining the unit's frequency regulation performance K. The frequency regulation revenue R is the product of the frequency regulation market clearing price p, the unit's frequency regulation mileage D, and the frequency regulation performance K within the billing cycle.

[0087] R = p × D × K(K1, K2, K3);

[0088] The commissioning cost of power plant units includes fuel costs C fuel and maintenance costs CO&M :

[0089] Fuel cost C fuel Including fuel costs of internal combustion engine generator sets C gas And the fuel cost of coal-fired power generation units C coal It can be obtained through the following calculation method:

[0090] C fuel =C gas +C coal ;

[0091] C gas =ΔT g_j ×f(M g ,P g_opera )×P gas (m);

[0092] C coal =ΔT c_j ×g(M c ,P c_opera )×P coal (m);

[0093] Where, f(M) g ,P g_opera The expression represents the amount of natural gas consumed by an internal combustion engine generator set per unit time (unit: cubic meters), and the number of internal combustion engine generator sets (M) put into operation during this time period. g Operating point P of the unit g_opera Related, g(M c ,P c_opera The figure represents the coal consumption (in tons) of a coal-fired power unit per unit time, and the number of coal-fired power generating units M put into operation during this time period. c Operating point P of the unit c_opera Related, P gas (m) represents the sales price of natural gas in month m (unit: yuan / cubic meter), P coal (m) represents the sales price of coal in the m-th month (unit: yuan / kg);

[0094] The operation and maintenance cost C of the power plant unit O&M Its annual operating hours T are related to the operating cost O(T) and maintenance cost Main(T), both of which are directly related to the actual operating hours of the unit. The operation and maintenance cost C of the internal combustion engine generator set is... gas_O&M The operation and maintenance cost of coal-fired power generating units C coal_O&M Specifically, it can be obtained through the following calculation method:

[0095]

[0096]

[0097] Where, N g_mon N represents the number of months the internal combustion engine unit has been in operation. c_mon N represents the number of months the coal-fired power unit has been in operation. g_day N represents the number of days an internal combustion engine unit is put into operation in a given month. c_day N represents the number of days a coal-fired power unit is put into operation in a given month. g_hour N represents the actual number of operating hours during the first few days of operation. c_hour This indicates the actual number of operating hours during the first day of operation. as well as and as well as Record the commissioning status of internal combustion engine generator sets and coal-fired generator sets separately;

[0098] Among them, with For example, its definition is as follows:

[0099]

[0100] by For example, its definition is as follows:

[0101]

[0102] Correspondingly, The value can indicate whether the coal-fired power generating unit is put into operation on day d. The value can indicate whether the coal-fired power generating unit is in operation within the h-th hour. The value can indicate whether the internal combustion engine generator set is put into operation on day d. It can indicate whether the internal combustion engine generator set is in operation within the h-hour period.

[0103] Based on the annual operation and maintenance cost calculation results, the operation and maintenance costs are converted to fuel costs per unit time. The conversion factors for internal combustion engine units and coal-fired units are α and β, respectively. Therefore, the operation and maintenance costs of internal combustion engine generator units and coal-fired generator units are as follows:

[0104] C gas_O&M =αC gas ;

[0105] C coal_O&M =βC coal ;

[0106] Furthermore, the above parameters must meet the following conditions:

[0107]

[0108] P g_j and P c_jΔP represents the output of the internal combustion engine and the coal-fired generator set before receiving the j-th AGC command, respectively; g and ΔP c This represents the actual output changes of the internal combustion engine and coal-fired power generation unit after receiving the AGC command. These two parameters are used for optimization decision-making, and are used to determine the AGC signal allocation and scheduling. g min and P g max represents the minimum and maximum output of the internal combustion engine unit, P c min and P c max represents the minimum and maximum output of a coal-fired power unit; V g,- and V g,+ This represents the upper and lower limits of the internal combustion engine unit's regulation rate, and its relationship with the load rate is a non-linear function; ΔT g_j and ΔT c_j P represents the response time of the internal combustion engine and the coal-fired power unit, respectively; AGC,j This indicates the amount of output to be increased or decreased as requested by the j-th AGC instruction.

[0109] Specifically, in the aforementioned combined power plant comprising coal-fired and internal combustion engine units, a 600MW coal-fired unit and an 18MW internal combustion engine unit can be selected. The frequency regulation rate can be determined by varying the load rates of these two units. Based on the dispatching system issuing AGC frequency regulation commands to the combined power plant between 11:00 and 12:00 on a given day, collaborative optimization is performed with economic optimization as the objective function. The constraints include ramp-up constraints for different unit types and frequency regulation capacity constraints. The optimized allocation results are as follows: Figure 5 As shown, calculations show that using the scheduling method provided in this application embodiment to decompose AGC signals, the annual revenue from frequency modulation ancillary services is approximately RMB 5.56 million, which significantly improves economic efficiency compared to traditional units.

[0110] Regarding the utilization of waste heat from flue gas, a certain type of internal combustion engine with a rated power of 16MW can be selected. Under 80% and 100% load rates, the exhaust gas temperatures are 393℃ and 370℃, respectively, and the flue gas flow rates are 21.29kg / s and 26.65kg / s, respectively. Assuming that the flue gas temperature after heat exchange is 90℃, the changes in flue gas temperature after heat exchange are 303℃ and 280℃, respectively. The corresponding heat absorbed by the condensate is 9031.22kJ / s and 10446.80kJ / s, respectively. Based on the power generation efficiency of coal-fired units, these can be converted into power outputs of 4200.36kW and 4851.53kW, respectively. By summing the power output from the waste heat recovery of flue gas with the rated power of the internal combustion engine, the total power output after waste heat recovery is calculated to be 17000.36kW and 20851.53kW. The total fuel consumption per unit time is calculated to be 28263.11kW and 34151.11kW based on the rated power and fuel conversion efficiency of the internal combustion engine. The calculated power generation efficiency of the internal combustion engine at 80% and 100% load rates is 60.15% and 61.06%, respectively. Therefore, it can be seen that the efficiency can be increased to over 60% after coupling the internal combustion engine with the coal-fired unit in the condensate stage according to this technical solution.

[0111] In this embodiment, the final allocation and scheduling model is determined by generating N frequency regulation scenarios and power plant profits. The allocation and scheduling model is used to determine the frequency regulation output that the internal combustion engine unit and the coal-fired unit need to respond to respectively, which can realize the rapid response of frequency regulation signals and optimize the economic efficiency of operation.

[0112] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0113] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods of the various embodiments of this application.

[0114] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A scheduling method, characterized in that, include: To obtain the first output of the coal-fired generator set and the second output of the internal combustion engine generator set; The first scheduling signal of the coal-fired generator set and the second scheduling signal of the internal combustion engine generator set are determined based on the first output and the second output. Send the first dispatch signal to the coal-fired generator set and send the second dispatch signal to the internal combustion engine generator set; The step of determining the first dispatch signal of the coal-fired power generator set and the second dispatch signal of the internal combustion engine power generator set based on the first output and the second output includes: The first power generation efficiency and the first frequency regulation rate of the coal-fired generator set are obtained, as well as the second power generation efficiency and the second frequency regulation rate of the internal combustion engine generator set. The third dispatch signal for the coal-fired power generator set and the fourth dispatch signal for the internal combustion engine power generator set are determined based on the first power generation efficiency, the first frequency regulation rate, the second power generation efficiency, the second frequency regulation rate, the first output, and the second output. Obtain the profit parameters corresponding to the frequency modulation power supply, and optimize and adjust the third scheduling signal and the fourth scheduling signal based on the profit parameters to determine the first scheduling signal and the second scheduling signal; The profit parameters are determined based on power generation revenue, frequency regulation revenue, fuel costs, and operation and maintenance costs. The electricity revenue It is obtained through the following calculation method: ； ； ； Indicates the grid connection price. and These represent the response times of the internal combustion engine and the coal-fired power unit, respectively. This indicates the power output of an internal combustion engine unit per unit time. This indicates the output power of a coal-fired power unit per unit time. and Respectively related to the number of units and and running points and Related; The frequency modulation revenue The frequency modulation mileage is confirmed by the following formula, based on the frequency modulation mileage and frequency modulation performance: ； This indicates the actual output value of the unit after receiving the AGC control command. This indicates the output value of the group when the AGC command is issued; The frequency modulation performance K is determined by the modulation rate, modulation accuracy, and response time; The adjustment rate It can be obtained through the following calculation method: ， ； Indicates the unit i No. j The rate of adjustment of the next adjustment This indicates the power output at the end of the unit's response to the AGC command. Indicates the time at which the event ends. This indicates the power output of the generator unit when it begins to respond to AGC commands. Indicates the starting time; This indicates the standard AGC adjustment rate of the units within the system; The adjustment accuracy It can be obtained through the following calculation method: ， ； Indicates the first i Taiwan unit j The deviation of the adjustment. This indicates the actual output of the unit during that time period. This indicates the AGC command value within that time period; fuel costs It is obtained through the following calculation method: ； ； ； This indicates the amount of natural gas consumed by an internal combustion engine generator set per unit of time. The number of internal combustion engine generator sets put into operation within the same time period as the internal combustion engine generator sets. Operating points of the operating units Related, This indicates the coal consumption per unit time of a coal-fired power unit. The number of coal-fired generating units put into operation within the same time period Operating points of the operating units Related, This represents the selling price of natural gas in month m. This represents the selling price of coal in month m. The maintenance costs include the maintenance costs of internal combustion engine generator sets and coal-fired generator sets.

2. A frequency-modulated power supply for use with the method as described in claim 1, characterized in that, This includes signal dispatching equipment, coal-fired power generator sets, and internal combustion engine power generator sets, among which: The first output terminal of the signal dispatching device is connected to the coal-fired generator set, and the second output terminal of the signal dispatching device is connected to the internal combustion engine generator set; The signal dispatching device is used to distribute dispatching signals to the coal-fired generator set and the internal combustion engine generator set.

3. The frequency modulation power supply as described in claim 2, characterized in that, The coal-fired power generation unit includes a boiler, a steam turbine, a condenser, a condensate pump, a low-pressure heater, a deaerator, a feedwater pump, a high-pressure heater, and a first generator, wherein: The first output terminal of the signal dispatching device is connected to the first input terminal of the boiler and the first input terminal of the steam turbine; The boiler's output end is connected to the second input end of the steam turbine; the steam turbine's first output end is connected to the input end of the condenser; the condenser's output end is connected to the input end of the condensate pump; the condensate pump's output end is connected to the input end of the low-pressure heater; the low-pressure heater's output end is connected to the input end of the deaerator; the deaerator's output end is connected to the input end of the feedwater pump; the feedwater pump's output end is connected to the input end of the high-pressure heater; and the high-pressure heater's output end is connected to the boiler's second input end. The second output terminal of the steam turbine is connected to the input terminal of the first generator.

4. The frequency modulation power supply as described in claim 3, characterized in that, The internal combustion engine generator set includes an internal combustion engine and a second generator. The second output terminal of the signal dispatching device is connected to the input terminal of the internal combustion engine, and the first output terminal of the internal combustion engine is connected to the input terminal of the second generator.

5. The frequency modulation power supply as described in claim 4, characterized in that, The internal combustion engine generator set also includes cylinder liners, heat exchangers, and exhaust systems, wherein: The second output terminal of the internal combustion engine is connected to the first input terminal of the cylinder liner, the first output terminal of the cylinder liner is connected to the input terminal of the internal combustion engine, and the first input terminal of the cylinder liner is connected to the first output terminal of the cylinder liner. The third output end of the internal combustion engine is connected to the first input end of the heat exchanger, the first output end of the heat exchanger is connected to the input end of the exhaust device, and the first input end of the heat exchanger is connected to the first output end of the heat exchanger. The output end of the condenser pump is connected to the second input end of the cylinder liner, the second output end of the cylinder liner is connected to the second input end of the heat exchanger, the second output end of the heat exchanger is connected to the input end of the deaerator, and the second input end of the cylinder liner is connected to the second output end of the cylinder liner, and the second input end of the heat exchanger is connected to the second output end of the heat exchanger.

6. The frequency modulation power supply as described in claim 5, characterized in that, The frequency-modulated power supply also includes a first valve, a second valve, and a third valve. The output end of the condenser pump is connected to the input end of the first valve. The first output end of the first valve is connected to the input end of the low-pressure heater. The second output end of the first valve is connected to the input end of the second valve. The output end of the second valve is connected to the second input end of the cylinder liner. The second output end of the heat exchanger is connected to the input end of the third valve, and the output end of the third valve is connected to the input end of the deaerator.

7. An electric power system, characterized in that, The power system includes the frequency-modulated power supply according to any one of claims 2 to 6.

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