Load control method and device for M701F4 gas turbine

Abstract

The present invention provides a load control method and device for an M701F4 gas turbine. The method comprises: when the M701F4 gas turbine is in load limit mode, obtaining frequency difference variation information of the power grid to which the M701F4 gas turbine is connected. A fuel quantity control instruction for the M701F4 gas turbine under a conventional control mode is calculated; based on the frequency difference variation information, the fuel quantity control instruction under the conventional control mode is optimized to obtain an optimized fuel quantity control instruction; and the optimized fuel quantity control instruction is used to adjust the amount of fuel involved in combustion, thereby controlling the power generation load of the M701F4 gas turbine. By implementing the method of the present invention, the M701F4 gas turbine incorporates the frequency difference variation information of the power grid to which the gas turbine is connected during load control in load limit mode, ensuring that the gas turbine can quickly and accurately achieve load control while also participating in primary frequency regulation in a timely manner.

Description

Technical Field

[0001] The present invention relates to the technical field of gas turbines, and in particular to a load control method and device for an M701F4 gas turbine. Background Art

[0002] In recent years, gas-steam combined cycle power generation has rapidly developed due to its clean, efficient, and fast response. Compared to traditional coal-fired units, gas turbines have an extremely fast load change rate. When adjusting the unit's load, the gas turbine has virtually no response lag and can quickly bring the unit load to the target value. The M701F4 gas turbine is a technologically mature 9F-class gas turbine developed by Mitsubishi Corporation of Japan and widely used in China. In the control logic of the M701F4 gas turbine, when unit coordinated control and automatic load regulation (ALR) are enabled, the gas turbine's load control can be divided into two main modes: GOVERNOR mode and LOAD LIMIT mode. The DCS (distributed control system) coordinates the control system to calculate the turbine load setpoint (ALR SET). The operator then selects one of the two load control modes and calculates the final fuel quantity command (CSO) to control the fuel flow involved in combustion, ultimately controlling the unit load.

[0003] The difference between the two load control modes is that the GOVERNOR mode converts the ALR SET into a speed setpoint SPSET, then calculates the fuel quantity command based on SPSET and the actual unit speed SPEED; while the LOAD LIMIT mode converts the ALR SET into an intermediate load setpoint LDSET, then calculates the fuel quantity command based on LDSET and the actual unit load ACTLD. In the LOAD LIMIT mode's control logic, load control is independent of unit speed. When the grid frequency changes, the unit cannot participate in primary frequency regulation. Although the ALR SET calculation includes a primary frequency regulation correction term for unit speed, the turbine load setpoint is strictly speed-limited. When the grid frequency changes, the unit speed changes, causing a change in the ALR SET. After the speed limit, the intermediate value LDSET changes. This process takes a considerable amount of time and does not meet the grid's requirements for unit primary frequency regulation. Because the unit cannot participate in primary frequency regulation in LOAD LIMIT mode, operators typically select the GOVERNOR mode. LOAD LIMIT mode is activated only when the grid frequency suddenly decreases dramatically, causing the GOVERNOR mode fuel quantity command (GVCSO) to increase momentarily and exceed the LOAD LIMIT mode fuel quantity command (LDCSO). In this case, to maintain load stability, the unit discontinues primary frequency regulation. However, this operating condition requires a grid frequency decrease rate exceeding 0.22 Hz / s, a very low probability occurrence. Therefore, LOAD LIMIT mode is only a theoretical load control method and is not typically used.

[0004] In summary, since the load limit mode cannot participate in the primary frequency regulation, this mode is only a nominal load control mode and is usually not used. There is an urgent need for a load control method that can enable the load control in the load limit mode to achieve load control quickly and accurately and participate in the primary frequency regulation in a timely manner. Summary of the Invention

[0005] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0006] The object of the present invention is to provide a load control method, device, electronic equipment and storage medium for an M701F4 gas turbine, so that the M701F4 gas turbine can introduce frequency difference change information of the power grid to which the gas turbine is connected during the load control process in the LOAD LIMIT mode, thereby ensuring that the gas turbine can participate in primary frequency regulation in a timely manner while achieving load control quickly and accurately.

[0007] The load control method for an M701F4 gas turbine provided in an embodiment of the first aspect of the present invention includes:

[0008] When the M701F4 gas turbine is in a LOAD LIMIT load control mode, obtaining frequency difference change information of a power grid to which the M701F4 gas turbine is connected;

[0009] Calculating and obtaining a fuel quantity control instruction for the M701F4 gas turbine under a conventional control method;

[0010] Based on the frequency difference change information, the fuel quantity control instruction under the traditional control method is optimized to obtain an optimized fuel quantity control instruction, wherein the optimized fuel quantity control instruction is used to adjust the amount of fuel involved in combustion to control the power generation load of the M701F4 gas turbine.

[0011] The load control method for an M701F4 gas turbine, provided in an embodiment of the first aspect of the present invention, involves obtaining frequency difference variation information of the power grid to which the M701F4 gas turbine is connected when the M701F4 gas turbine is in a load limit load control mode, calculating a fuel quantity control instruction for the M701F4 gas turbine under a conventional control mode, and optimizing the fuel quantity control instruction under the conventional control mode based on the frequency difference variation information to obtain an optimized fuel quantity control instruction. The optimized fuel quantity control instruction is used to adjust the amount of fuel involved in combustion, thereby controlling the power generation load of the M701F4 gas turbine. Thus, the M701F4 gas turbine incorporates the frequency difference variation information of the power grid to which the gas turbine is connected during the load control process in the load limit mode, ensuring that the gas turbine can quickly and accurately achieve load control while also participating in primary frequency regulation in a timely manner.

[0012] The load control device for an M701F4 gas turbine provided in an embodiment of the second aspect of the present invention comprises:

[0013] an acquisition module, configured to acquire frequency difference change information of a power grid to which the M701F4 gas turbine is connected when the M701F4 gas turbine is in a load limit load control mode;

[0014] a calculation module, configured to calculate a fuel quantity control instruction for the M701F4 gas turbine under a conventional control mode;

[0015] An optimization module is used to optimize the fuel quantity control instruction under the traditional control method based on the frequency difference change information to obtain an optimized fuel quantity control instruction, wherein the optimized fuel quantity control instruction is used to adjust the amount of fuel involved in combustion to control the power generation load of the M701F4 gas turbine.

[0016] The load control device for an M701F4 gas turbine, according to a second embodiment of the present invention, obtains frequency difference variation information of the power grid to which the M701F4 gas turbine is connected when the M701F4 gas turbine is in load limit load control mode, calculates a fuel quantity control instruction for the M701F4 gas turbine under a conventional control mode, and optimizes the fuel quantity control instruction under the conventional control mode based on the frequency difference variation information to obtain an optimized fuel quantity control instruction. The optimized fuel quantity control instruction is used to adjust the amount of fuel involved in combustion, thereby controlling the power generation load of the M701F4 gas turbine. Thus, the M701F4 gas turbine incorporates frequency difference variation information of the power grid to which the gas turbine is connected during load control in load limit mode, ensuring that the gas turbine can quickly and accurately achieve load control while also participating in primary frequency regulation in a timely manner.

[0017] The electronic device proposed in the embodiment of the third aspect of the present invention includes: a memory, a processor, and a computer program stored in the memory and runnable on the processor. When the processor executes the program, it implements the load control method of the M701F4 gas turbine proposed in the embodiment of the first aspect of the present invention.

[0018] The fourth embodiment of the present invention proposes a non-temporary computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the load control method for the M701F4 gas turbine proposed in the first embodiment of the present invention.

[0019] The fifth embodiment of the present invention provides a computer program product. When the instructions in the computer program product are executed by a processor, the load control method of the M701F4 gas turbine proposed in the first embodiment of the present invention is executed.

[0020] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0022] Figure 1 1 is a flow chart of a load control method for an M701F4 gas turbine provided by a first embodiment of the present invention;

[0023] Figure 2 1 is a flow chart of a load control method for an M701F4 gas turbine provided by a second embodiment of the present invention;

[0024] Figure 3This is a schematic diagram of the output of the dead zone and limiter link proposed in the present invention;

[0025] Figure 4 1 is a flow chart of a load control method for an M701F4 gas turbine provided by a third embodiment of the present invention;

[0026] Figure 5 is a load control logic diagram proposed according to the present invention;

[0027] Figure 6 is a schematic diagram of the power grid frequency change assumed according to the present invention;

[0028] Figure 7 2. It is a schematic diagram of the curve change of the primary frequency modulation feedforward amount obtained according to the present invention;

[0029] Figure 8 Schematic diagram of the structure of the load control device of the M701F4 gas turbine proposed in the present invention;

[0030] Figure 9 A block diagram is shown of an exemplary electronic device suitable for implementing embodiments of the present invention. DETAILED DESCRIPTION

[0031] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention. On the contrary, the embodiments of the present invention include all variations, modifications, and equivalents that fall within the spirit and scope of the appended claims.

[0032] Figure 1 It is a flow chart of a load control method for an M701F4 gas turbine provided by the first embodiment of the present invention.

[0033] It should be noted that the load control method for the M701F4 gas turbine of this embodiment is performed by a load control device for the M701F4 gas turbine, which can be implemented by software and / or hardware and can be configured in an electronic device.

[0034] like Figure 1 As shown, the load control method of the M701F4 gas turbine includes:

[0035] S101: When the M701F4 gas turbine is in a LOAD LIMIT load control mode, frequency difference change information of the power grid to which the M701F4 gas turbine is connected is obtained.

[0036] It is understandable that the load control method proposed in the present invention can be applied not only to the M701F4 gas turbine, but also to any other type of gas turbine to which the load control method is applicable, without limitation.

[0037] The frequency difference refers to the difference between the frequency of the grid to which the M701F4 gas turbine is connected and a specified frequency (e.g., 50 Hz). The frequency difference change information refers to information related to the frequency difference of the grid to which the M701F4 gas turbine is connected.

[0038] In an embodiment of the present invention, when the M701F4 gas turbine is in the LOAD LIMIT load control mode, obtaining frequency difference change information of the power grid to which the M701F4 gas turbine is connected can provide reliable optimization information for subsequent optimization of the fuel quantity control instruction under the traditional control method.

[0039] S102: Calculate and obtain a fuel quantity control instruction for the M701F4 gas turbine under a conventional control method.

[0040] Among them, the fuel quantity control instruction under the traditional control mode is used to adjust the fuel quantity participating in the combustion of the M701F4 gas turbine under the traditional control mode.

[0041] In the embodiment of the present invention, the fuel quantity control instruction of the M701F4 gas turbine under the traditional control mode is calculated, which can provide reliable data support for the subsequent optimized fuel quantity control instruction.

[0042] S103: Based on the frequency difference change information, the fuel quantity control instruction under the traditional control method is optimized to obtain an optimized fuel quantity control instruction, wherein the optimized fuel quantity control instruction is used to adjust the amount of fuel involved in combustion to control the power generation load of the M701F4 gas turbine.

[0043] The optimized fuel quantity control instruction refers to a fuel quantity control instruction obtained by optimizing the fuel quantity control instruction under the traditional control method based on the frequency difference change information.

[0044] It can be understood that when load control is performed based on the fuel quantity control instruction under the traditional control method, the M701F4 gas turbine cannot participate in the primary frequency modulation. However, in the present invention, when the fuel quantity control instruction under the traditional control method is optimized based on the frequency difference change information and the optimized fuel quantity control instruction is obtained, the load control of this mode can achieve both load control and participate in the primary frequency modulation.

[0045] In this embodiment, when the M701F4 gas turbine is in LOAD LIMIT load control mode, frequency difference variation information of the power grid to which the M701F4 gas turbine is connected is obtained to calculate a fuel quantity control command for the M701F4 gas turbine under a conventional control mode. Based on the frequency difference variation information, the conventional fuel quantity control command is optimized to obtain an optimized fuel quantity control command. The optimized fuel quantity control command is used to adjust the amount of fuel involved in combustion, thereby controlling the power generation load of the M701F4 gas turbine. Thus, the M701F4 gas turbine incorporates frequency difference variation information of the power grid to which the gas turbine is connected during load control in LOAD LIMIT mode, ensuring that the gas turbine can quickly and accurately achieve load control while also participating in primary frequency regulation in a timely manner.

[0046] Figure 2 It is a flow chart of a load control method for an M701F4 gas turbine provided by the second embodiment of the present invention.

[0047] like Figure 2 As shown, the load control method of the M701F4 gas turbine includes:

[0048] S201: When the M701F4 gas turbine is in the LOAD LIMIT load control mode, frequency difference change information of the power grid to which the M701F4 gas turbine is connected is obtained.

[0049] The description of S201 can be found in the above embodiment and will not be repeated here.

[0050] S202: Obtain the engine load instruction, speed deviation signal, and actual power generation load of the M701F4 gas turbine.

[0051] The gas turbine load instruction refers to an instruction issued by the coordinated control system for controlling the gas turbine load.

[0052] The speed deviation signal may be a signal used to describe the deviation between the actual speed and the preset speed of the M701F4 gas turbine.

[0053] The actual power generation load may refer to the power generation load of the M701F4 gas turbine in an actual operating environment.

[0054] In the embodiment of the present invention, when the engine load instruction, the speed deviation signal and the actual power generation load of the M701F4 gas turbine are obtained, the fuel quantity control instruction under the traditional control method can be calculated.

[0055] S203: Based on the engine load command, the speed deviation signal and the actual power generation load, a fuel quantity control command under the traditional control method is calculated.

[0056] That is to say, in the embodiment of the present invention, the engine load instruction, speed deviation signal and actual power generation load of the M701F4 gas turbine can be obtained, and based on the engine load instruction, speed deviation signal and actual power generation load, the fuel quantity control instruction under the traditional control method is calculated.

[0057] S204: Determine the power grid frequency difference feedforward amount based on the frequency difference change information.

[0058] Feedforward refers to preemptive control based on the magnitude of a disturbance, before the controlled variable changes, to compensate for its impact on the controlled variable. Grid frequency difference feedforward, on the other hand, refers to a feedforward based on frequency difference information, used to compensate for the fuel quantity command under traditional control methods.

[0059] Optionally, in some embodiments, when determining the power grid frequency difference feedforward amount based on the frequency difference change information, the initial frequency difference signal in the frequency difference change information can be processed based on the primary frequency regulation dead zone and the limiting link to obtain the processed frequency difference signal, and the change characteristics of the processed frequency difference signal are determined. Based on the change characteristics, a transfer function corresponding to the processed frequency difference signal is determined, wherein the transfer function is used to perform lead compensation and / or lag compensation on the processed frequency difference signal. The processed frequency difference signal is compensated based on the transfer function to obtain the power grid frequency difference feedforward amount, thereby effectively improving the accuracy of the obtained power grid frequency difference feedforward amount.

[0060] Primary frequency regulation refers to the automatic control process in which the control system of the generator sets automatically increases or decreases the active power of the generator sets when the grid frequency deviates from the rated value, limiting grid frequency fluctuations and maintaining a stable grid frequency. To prevent frequent fluctuations in generator load due to factors such as sensor measurement errors, a dead zone is set for the grid frequency difference during primary frequency regulation. When the grid frequency difference amplitude is less than the dead zone value, the dead zone link output is 0. When the grid frequency difference amplitude is greater than the limit value, the limit link output is the limit value.

[0061] For example, if Figure 3 As shown, Figure 3 This is an output diagram of the dead zone and amplitude limiting link proposed in the present invention. In order to prevent frequent fluctuations in the unit load due to factors such as sensor measurement errors, the primary frequency regulation dead zone value is configured to ±0.0333Hz, the upper limit value of the grid frequency difference is configured to ±0.1833Hz, and the output frequency of the dead zone amplitude limiting module should be as follows: Figure 3 shown.

[0062] The initial frequency difference signal refers to the unprocessed frequency difference signal, and the processed frequency difference signal refers to the frequency difference signal obtained after the initial frequency difference signal is processed through the dead zone and limiter links.

[0063] Optionally, in some embodiments, the primary frequency modulation dead zone and amplitude limiting link includes: a dead zone link and an amplitude limiting link.

[0064] S205: summing the fuel quantity instruction under the traditional control mode and the grid frequency difference feedforward quantity to obtain an optimized fuel quantity control instruction.

[0065] That is to say, in an embodiment of the present invention, after obtaining the frequency difference change information and the fuel quantity instruction under the traditional control method, the grid frequency difference feedforward amount can be determined based on the frequency difference change information, and the fuel quantity instruction under the traditional control method and the grid frequency difference feedforward amount can be summed to obtain the optimized fuel quantity control instruction. In this way, the load control of the LOAD LIMIT mode can not only achieve fast and accurate load control but also participate in primary frequency regulation.

[0066] In this embodiment, the grid frequency difference feedforward is determined based on the frequency difference change information, and the fuel quantity instruction under the traditional control method is summed with the grid frequency difference feedforward to obtain the optimized fuel quantity control instruction. As a result, the load control of the LOADLIMIT mode can achieve both rapid and accurate load control and participate in the primary frequency regulation. The initial frequency difference signal in the frequency difference change information is processed based on the primary frequency regulation dead zone and the limiting link to obtain the processed frequency difference signal, and the change characteristics of the processed frequency difference signal are determined. Based on the change characteristics, the transfer function corresponding to the processed frequency difference signal is determined, wherein the transfer function is used to perform lead compensation and / or lag compensation on the processed frequency difference signal, and the processed frequency difference signal is compensated based on the transfer function to obtain the grid frequency difference feedforward. As a result, the accuracy of the obtained grid frequency difference feedforward can be effectively improved. By obtaining the engine load instruction, speed deviation signal and actual power generation load of the M701F4 gas turbine, the fuel quantity control instruction under the traditional control method can be calculated.

[0067] Figure 4 It is a flow chart of a load control method for an M701F4 gas turbine provided by the third embodiment of the present invention.

[0068] like Figure 4 As shown, the load control method of the M701F4 gas turbine includes:

[0069] S401: When the M701F4 gas turbine is in the LOAD LIMIT load control mode, frequency difference change information of the power grid to which the M701F4 gas turbine is connected is obtained.

[0070] S402: Calculate and obtain a fuel quantity control instruction for the M701F4 gas turbine under a conventional control method.

[0071] S403: Processing the initial frequency difference signal in the frequency difference change information based on the primary frequency modulation dead zone and the amplitude limiting link to obtain a processed frequency difference signal.

[0072] S404: Determine the change characteristics of the processed frequency difference signal.

[0073] The description of S401 - S404 can be found in the above embodiment and will not be repeated here.

[0074] S405: When the change characteristic meets the preset condition, construct a transfer function based on the first lag time constant and the lead time constant, wherein the preset condition refers to that the derivative of the processed frequency difference signal within a preset time period is continuously greater than or equal to a preset threshold.

[0075] The preset time period may be, for example, 0.1 s, and the corresponding preset threshold may be 0.2 Hz / s.

[0076] The first lag time constant and the lead time constant may be constants configured in advance for constructing a transfer function based on the change characteristic satisfying the first preset condition. In an embodiment of the present invention, the first lag time constant may be 500, and the lead time constant may be 0. Of course, the first lag time constant and the lead time constant may also be any other possible values, without limitation.

[0077] S406: When the change characteristic does not meet the preset condition, construct a transfer function based on the second lag time constant and the lead time constant.

[0078] The second lag time constant may be, for example, a constant of 1.

[0079] That is, in the embodiment of the present invention, when the variation characteristic does not satisfy the preset condition, a transfer function may be constructed based on the second lag time constant and the lead time constant.

[0080] S407: When the change characteristic meets a preset condition, update the transfer function based on the first lag time constant.

[0081] That is, in the embodiment of the present invention, after constructing the transfer function based on the second lag time constant and the lead time constant, if the variation characteristics meet the preset conditions, the transfer function may be updated based on the first lag time constant.

[0082] S408: Perform lead compensation and / or lag compensation on the processed frequency difference signal based on the transfer function to obtain a reference feedforward amount.

[0083] The reference feedforward amount refers to the feedforward amount obtained by performing lead compensation and / or lag compensation on the processed frequency difference signal through a transfer function.

[0084] S409: Obtain the speed differential and unit characteristic information of the M701F4 gas turbine.

[0085] The speed droop ratio refers to the percentage of the difference between the no-load speed and the full-load speed to the rated speed when the turbine is operating alone. The unit characteristic information can be used to indicate the unit characteristics of the gas turbine.

[0086] S410: Determine a feedforward correction coefficient based on the speed inequality and unit characteristic information.

[0087] The feedforward correction coefficient can be used to correct the reference feedforward to obtain the grid frequency difference feedforward.

[0088] S411: Processing the reference feedforward quantity based on the feedforward quantity correction coefficient to obtain the grid frequency difference feedforward quantity.

[0089] That is, in an embodiment of the present invention, after obtaining the transfer function, lead compensation and / or lag compensation can be performed on the processed frequency difference signal based on the transfer function to obtain a reference feedforward. The speed inequality and unit characteristic information of the M701F4 gas turbine are obtained, and a feedforward correction coefficient is determined based on the speed inequality and unit characteristic information. The reference feedforward is processed based on the feedforward correction coefficient to obtain a power grid frequency difference feedforward. Thus, in the process of obtaining the feedforward correction coefficient, the speed inequality and unit characteristic information of the gas turbine can be effectively combined, thereby ensuring the correction effect of the feedforward correction coefficient on the reference feedforward.

[0090] S412: summing the fuel quantity instruction under the traditional control mode and the grid frequency difference feedforward quantity to obtain an optimized fuel quantity control instruction.

[0091] The description of S412 can be found in the above embodiment and will not be repeated here.

[0092] For example, if Figure 5 As shown, Figure 5 This is a load control logic diagram proposed by the present invention. Based on the load control in the traditional LOAD LIMIT mode, the present invention introduces the feedforward of the grid frequency difference signal. Define the frequency difference signal as Δf and the grid frequency as f, and we have:

[0093] Δf=50-f (1)

[0094] The invention comprises: a pure delay module (1), a correction function of the speed deviation to the load instruction (2), an adder (3), a limit module (4), a subtractor (5)(11), an upper limit alarm (6), a lower limit alarm (7), an analog register module (8), a speed limit module (9), a deviation correction function (10), a multiplier (12), a range conversion module (13), a PID controller (14), a dead-zone limit function of the grid frequency difference (15), a differential module (16), a high limit module (17), a rising delay trigger (18), an RS trigger (19), an analog selector module (20), a constant module (21)(22)(23), a lead-lag link (24), and a correction coefficient of the grid frequency difference feedforward (25).

[0095] The engine load command from the DCS coordinated control system is summed with the correction signal of the engine speed deviation load command after passing through the pure delay module (1), and the engine load command ALR SET is obtained after being limited. The difference between the ALR SET and LDSET signals is calculated. If the deviation exceeds the preset upper limit, the register (8) is continuously accumulated and LDSET is gradually increased until the deviation between ALR SET and LDSET is lower than the upper limit. On the contrary, if the deviation between ALR SET and LDSET is lower than the lower limit, the register (8) is continuously accumulated and LDSET is gradually reduced until the deviation between the two exceeds the lower limit.

[0096] The difference between the speed-limited LDSET and the actual power generation load ACTLD of the gas turbine is calculated, and the deviation is corrected according to the value of LDSET through the deviation correction function (10). When LDSET is larger, the deviation correction becomes larger, and when LDSET is smaller, the deviation correction becomes smaller. The corrected deviation between LDSET and ACTLD is converted to a range of 0 to 100 by the range conversion module (13) and input into the PID controller (14). The PID controller calculates the fuel quantity command LDCSO in the load limit mode.

[0097] From the above analysis, it can be seen that the load control in LOAD LIMIT mode only involves the grid frequency difference (i.e., the turbine speed deviation) when calculating the turbine load set value ALRSET, and then goes through a series of speed and amplitude limiting links, which cannot meet the grid's primary frequency regulation requirements for the unit.

[0098] In order to prevent frequent fluctuations in the unit load due to factors such as sensor measurement errors, a dead zone must be set for the grid frequency difference during primary frequency regulation. In the dead zone limit function (15), the primary frequency regulation dead zone value is ±0.0333Hz. The unit needs to set an upper limit for the primary frequency regulation. When the grid frequency is too low or too high, in order to maintain safe and stable operation of the unit, it should no longer participate in the primary frequency regulation. The upper limit of the grid frequency difference is ±0.1833Hz. When the grid frequency difference reaches the upper limit, the grid takes measures such as cutting off part of the load or adjusting the unit load instruction through AGC (automatic generation control) to maintain the stability of the grid frequency. The curve of the dead zone limit function (15) is as shown above. Figure 4 shown.

[0099] The upper limit module (17) has a limit value of 0.2Hz / s. When the grid frequency drops suddenly, it can be seen from formula (1) that the derivative of the grid frequency difference suddenly rises, triggering the upper limit module. After 0.1s, the output of the rising delay module (18) becomes 1, the RS trigger (19) is triggered, and the analog selector module (20) selects the constant 500 (i.e., the first lag time constant) as the lag time constant U1 of the lead-lag module (24). Until the grid frequency returns to stability, the operator manually resets the RS trigger (19), and the analog selector (20) selects the constant 1 (i.e., the second lag time constant) as the lag time constant U1 of the lead-lag module (24). The lead time constant U2 of the lead-lag module is fixed to 0.

[0100] The transfer function expression of the lead-lag module (24) is:

[0101]

[0102] When the grid frequency difference derivative is small, we have:

[0103]

[0104] The lead-lag link plays the role of inertia filtering. When the derivative of the grid frequency difference is large, there is:

[0105]

[0106] Since the inertia time constant is very large, no matter how the grid frequency difference changes, the output of the lead-lag link (24) remains basically unchanged, which is equivalent to cutting off the primary frequency regulation function and maintaining the unit load stability.

[0107] The correction coefficient (25) of the grid frequency difference feedforward quantity is set to 24.

[0108] In this embodiment, when the variation characteristics meet a preset condition, a transfer function is constructed based on a first lag time constant and a lead time constant, wherein the preset condition refers to the derivative of the processed frequency difference signal being continuously greater than or equal to a preset threshold value within a preset time period. When the variation characteristics do not meet the preset condition, a transfer function is constructed based on a second lag time constant and a lead time constant, and after the variation characteristics meet the preset condition, the transfer function is updated based on the first lag time constant. This effectively improves the applicability of the resulting transfer function in different application scenarios. The processed frequency difference signal is compensated by the transfer function to obtain a reference feedforward quantity, and the speed inequality and unit characteristic information of the M701F4 gas turbine are obtained. Based on the speed inequality and unit characteristic information, a feedforward quantity correction coefficient is determined, and the reference feedforward quantity is processed based on the feedforward quantity correction coefficient to obtain a grid frequency difference feedforward quantity. Thus, the speed inequality and unit characteristic information of the gas turbine can be effectively combined in the process of obtaining the feedforward quantity correction coefficient, thereby ensuring the correction effect of the feedforward quantity correction coefficient on the reference feedforward quantity.

[0109] For example, at the initial moment, according to the load control method designed by the present invention, the gas turbine performs load control in the LOAD LIMIT mode and participates in a frequency modulation. Assume that at the 20th second, a fault occurs in the power grid, causing the power grid frequency to drop instantaneously, and then the power grid frequency slowly recovers until it returns to normal at the 30th second. At the 40th second, the operator manually resets the RS trigger (19) and continues to participate in a frequency modulation. Figure 6 As shown, Figure 6 This is a schematic diagram of the power grid frequency change assumed according to the present invention. For this schematic diagram of the power grid frequency change, see Figure 7 , Figure 7 Schematic diagram of the curve change of the primary frequency modulation feedforward amount obtained according to the present invention.

[0110] from Figure 7 As can be seen from the load control method designed in the present invention, the gas turbine in LOAD LIMIT mode can adjust the primary frequency modulation feedforward of the load control PID according to changes in the grid frequency, thereby adjusting the fuel flow rate, changing the gas turbine load, and participating in the primary frequency modulation. When the grid frequency drops suddenly, the hysteresis time constant can be updated to the first hysteresis time constant. This very large hysteresis time can effectively cut off the primary frequency modulation in a timely manner, maintaining a stable gas turbine load. Once the grid frequency returns to normal, the operator can reset the RS trigger to resume participating in the primary frequency modulation.

[0111] Figure 8 It is a structural schematic diagram of the load control device of the M701F4 gas turbine proposed in accordance with the present invention.

[0112] like Figure 8 As shown, the load control device 80 of the M701F4 gas turbine includes:

[0113] An acquisition module 801 is configured to acquire frequency difference change information of a power grid to which the M701F4 gas turbine is connected when the M701F4 gas turbine is in a load limit control mode;

[0114] The calculation module 802 is used to calculate the fuel quantity control instruction of the M701F4 gas turbine under the traditional control mode;

[0115] The optimization module 803 is used to optimize the fuel quantity control instruction under the traditional control method based on the frequency difference change information to obtain an optimized fuel quantity control instruction, wherein the optimized fuel quantity control instruction is used to adjust the amount of fuel involved in combustion to control the power generation load of the M701F4 gas turbine.

[0116] It should be noted that the aforementioned explanation of the load control method for the M701F4 gas turbine is also applicable to the load control device for the M701F4 gas turbine of this embodiment, and will not be repeated here.

[0117] In this embodiment, when the M701F4 gas turbine is in the LOAD LIMIT load control mode, frequency difference change information of the power grid to which the M701F4 gas turbine is connected is obtained, and a fuel quantity control instruction for the M701F4 gas turbine under the traditional control mode is calculated. Based on the frequency difference change information, the fuel quantity control instruction under the traditional control mode is optimized to obtain an optimized fuel quantity control instruction, wherein the optimized fuel quantity control instruction is used to adjust the amount of fuel participating in combustion and thus control the power generation load of the M701F4 gas turbine. As a result, the M701F4 gas turbine introduces the frequency difference change information of the power grid to which the gas turbine is connected during the load control process in the LOAD LIMIT mode, ensuring that the gas turbine can quickly and accurately achieve load control while timely participating in primary frequency regulation.

[0118] Figure 9 A block diagram is shown of an exemplary electronic device suitable for implementing embodiments of the present invention. Figure 9 The electronic device 12 shown is only an example and should not limit the functionality and scope of use of the embodiments of the present invention.

[0119] like Figure 9 As shown, electronic device 12 is implemented as a general-purpose computing device. Components of electronic device 12 may include, but are not limited to, one or more processors or processing units 16, system memory 28, and a bus 18 that connects various system components (including system memory 28 and processing unit 16).

[0120] Bus 18 represents one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, a processor, or a local bus using any of a variety of bus architectures. Examples of such architectures include, but are not limited to, the Industry Standard Architecture (ISA) bus, the Micro Channel Architecture (MAC) bus, the Enhanced ISA bus, the Video Electronics Standards Association (VESA) local bus, and the Peripheral Component Interconnection (PCI) bus.

[0121] The electronic device 12 typically includes a variety of computer system readable media. These media can be any available media that can be accessed by the electronic device 12, including volatile and non-volatile media, removable and non-removable media.

[0122] The memory 28 may include computer system readable media in the form of volatile memory, such as random access memory (RAM) 30 and / or cache memory 32. The electronic device 12 may further include other removable / non-removable, volatile / non-volatile computer system storage media. By way of example only, the storage system 34 may be configured to read and write non-removable, non-volatile magnetic media ( Figure 9 Not shown, often called a "hard drive").

[0123] although Figure 9 Although not shown, a disk drive for reading and writing to a removable non-volatile disk (e.g., a floppy disk) and an optical disk drive for reading and writing to a removable non-volatile optical disk (e.g., a Compact Disc Read Only Memory (CD-ROM), a Digital Video Disc Read Only Memory (DVD-ROM), or other optical media) may be provided. In these cases, each drive may be connected to bus 18 via one or more data media interfaces. Memory 28 may include at least one program product having a set (e.g., at least one) of program modules configured to perform the functions of various embodiments of the present invention.

[0124] A program / utility 40 having a set (at least one) of program modules 42 may be stored, for example, in memory 28. Such program modules 42 include, but are not limited to, an operating system, one or more application programs, other program modules, and program data, each of which, or some combination thereof, may include an implementation of a network environment. Program modules 42 generally perform the functions and / or methods of the embodiments described herein.

[0125] The electronic device 12 can also communicate with one or more external devices 14 (e.g., a keyboard, pointing device, display 24, etc.), one or more devices that enable human interaction with the electronic device 12, and / or any device that enables the electronic device 12 to communicate with one or more other computing devices (e.g., a network card, a modem, etc.). This communication can occur via an input / output (I / O) interface 22. Furthermore, the electronic device 12 can communicate with one or more networks (e.g., a local area network (LAN), a wide area network (WAN), and / or a public network such as the Internet) via a network adapter 20. As shown, the network adapter 20 communicates with other modules of the electronic device 12 via a bus 18. It should be understood that, although not shown, other hardware and / or software modules can be used in conjunction with the electronic device 12, including but not limited to microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0126] The processing unit 16 executes various functional applications and data processing by running programs stored in the system memory 28 , such as implementing the load control method of the M701F4 gas turbine mentioned in the above embodiment.

[0127] In order to implement the above embodiments, the present invention also proposes a non-temporary computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the load control method of the M701F4 gas turbine proposed in the above embodiments of the present invention is implemented.

[0128] In order to implement the above embodiments, the present invention further proposes a computer program product. When the instruction processor in the computer program product executes, the load control method of the M701F4 gas turbine proposed in the above embodiments of the present invention is executed.

[0129] Other embodiments of the present invention will readily occur to those skilled in the art after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention that follow from the general principles of the invention and include common knowledge or customary techniques in the art not invented herein. The description and examples are to be considered as exemplary only, with the true scope and spirit of the invention being indicated by the following claims.

[0130] It should be understood that the present invention is not limited to the exact construction described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

[0131] It should be noted that, in the description of the present invention, the terms "first," "second," etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0132] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0133] It should be understood that various parts of the present invention can be implemented using hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application-specific integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0134] Those skilled in the art will understand that all or part of the steps in the method of the above embodiment can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

[0135] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing module, or each unit may exist physically separately, or two or more units may be integrated into a single module. The aforementioned integrated modules may be implemented in the form of hardware or in the form of software functional modules. If the integrated modules are implemented in the form of software functional modules and sold or used as independent products, they may also be stored in a computer-readable storage medium.

[0136] The storage medium mentioned above can be a read-only memory, a magnetic disk or an optical disk, etc.

[0137] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0138] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A load control method for an M701F4 gas turbine, characterized in that: include: When the M701F4 gas turbine is in a LOAD LIMIT load control mode, obtaining frequency difference change information of a power grid to which the M701F4 gas turbine is connected; Calculating and obtaining a fuel quantity control instruction for the M701F4 gas turbine under a conventional control method; Based on the frequency difference change information, optimizing the fuel quantity control instruction under the traditional control mode to obtain an optimized fuel quantity control instruction, wherein the optimized fuel quantity control instruction is used to adjust the amount of fuel involved in combustion to control the power generation load of the M701F4 gas turbine; The step of optimizing the fuel quantity control instruction under the traditional control mode based on the frequency difference change information to obtain the optimized fuel quantity control instruction includes: Determining a power grid frequency difference feedforward amount based on the frequency difference change information; Summing the fuel quantity instruction under the traditional control mode and the grid frequency difference feedforward amount to obtain the optimized fuel quantity control instruction; Wherein, determining the grid frequency difference feedforward amount based on the frequency difference change information includes: Processing the initial frequency difference signal in the frequency difference change information based on the primary frequency modulation dead zone and the amplitude limiting link to obtain a processed frequency difference signal; Determining a change characteristic of the processed frequency difference signal; determining a transfer function corresponding to the processed frequency difference signal based on the change characteristic, wherein the transfer function is used to perform lead compensation and / or lag compensation on the processed frequency difference signal; The processed frequency difference signal is compensated based on the transfer function to obtain the power grid frequency difference feedforward amount.

2. The method according to claim 1, wherein The determining, based on the change characteristic, a transfer function corresponding to the processed frequency difference signal includes: When the change characteristic meets a preset condition, the transfer function is constructed based on a first lag time constant and a lead time constant, wherein the preset condition refers to that the derivative of the processed frequency difference signal within a preset time period is continuously greater than or equal to a preset threshold.

3. The method according to claim 2, wherein The determining, based on the change characteristic, a transfer function corresponding to the processed frequency difference signal further includes: When the variation characteristic does not satisfy the preset condition, the transfer function is constructed based on a second lag time constant and the lead time constant.

4. The method according to claim 3, wherein After constructing the transfer function based on the second lagging time constant and the leading time constant, the method further includes: When the change characteristic meets a preset condition, the transfer function is updated based on a first lag time constant.

5. The method according to claim 1, wherein The primary frequency modulation dead zone and amplitude limiting link include: Dead zone link; Limiting link.

6. The method according to claim 1, wherein The compensating the processed frequency difference signal based on the transfer function to obtain the grid frequency difference feedforward amount includes: Performing lead compensation and / or lag compensation on the processed frequency difference signal based on the transfer function to obtain a reference feedforward amount; Obtaining speed droop and unit characteristic information of the M701F4 gas turbine; Determining a feedforward correction coefficient based on the speed inequality and the unit characteristic information; The reference feedforward amount is processed based on the feedforward amount correction coefficient to obtain the grid frequency difference feedforward amount.

7. The method according to any one of claims 1 to 6, wherein: The calculation to obtain the fuel quantity control instruction of the M701F4 gas turbine under the traditional control mode includes: Obtaining a combustion engine load instruction, a speed deviation signal, and an actual power generation load of the M701F4 gas turbine; Based on the combustion engine load instruction, the speed deviation signal and the actual power generation load, a fuel quantity control instruction under the traditional control method is calculated.

8. A load control device for an M701F4 gas turbine, characterized in that: include: an acquisition module, configured to acquire frequency difference change information of a power grid to which the M701F4 gas turbine is connected when the M701F4 gas turbine is in a load limit load control mode; a calculation module, configured to calculate a fuel quantity control instruction for the M701F4 gas turbine under a conventional control mode; an optimization module, configured to optimize the fuel quantity control instruction under the conventional control mode based on the frequency difference change information to obtain an optimized fuel quantity control instruction, wherein the optimized fuel quantity control instruction is used to adjust the amount of fuel involved in combustion to control the power generation load of the M701F4 gas turbine; Wherein, the optimization module includes: a determining unit, configured to determine a power grid frequency difference feedforward amount based on the frequency difference change information; An instruction processing unit, configured to sum the fuel quantity instruction under the traditional control mode and the grid frequency difference feedforward amount to obtain the optimized fuel quantity control instruction; The determining unit is specifically configured to: Processing the initial frequency difference signal in the frequency difference change information based on the primary frequency modulation dead zone and the amplitude limiting link to obtain a processed frequency difference signal; Determining a change characteristic of the processed frequency difference signal; determining a transfer function corresponding to the processed frequency difference signal based on the change characteristic, wherein the transfer function is used to perform lead compensation and / or lag compensation on the processed frequency difference signal; The processed frequency difference signal is compensated based on the transfer function to obtain the power grid frequency difference feedforward amount.

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