Dynamic feed-forward control method and device for coal-fired power generating unit and power generating unit

Abstract

The invention discloses a dynamic feedforward control method and device for a coal-fired power generating unit and the power generating unit. The dynamic feedforward control method comprises the following steps: acquiring a target load instruction and a rate-limiting post-load instruction of a current generator set; determining a first feed-forward quantity function and inertia time according to the deviation between the target load instruction and the load instruction after the speed limit; obtaining a current operation parameter and a current set parameter of the generator set, determining a correction coefficient according to the current operation parameter and the current set parameter, and correcting the first feed-forward quantity function according to the correction coefficient to obtain a second feed-forward quantity function; and substituting the deviation between the target load instruction and the load instruction after the speed limit rate into a second feed-forward quantity function to obtain a boiler master control dynamic feed-forward quantity, and outputting the boiler master control dynamic feed-forward quantity to the boiler master control of the generator set after inertia time so as to adjust the fuel quantity of the generator set. According to the method, the boiler coal quantity can be matched with the actual load demand energy of the unit when the load of the unit changes quickly and frequently, and accurate control over the load of the unit is achieved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of thermal power generation, and in particular to a dynamic feedforward control method and device for a coal-fired generator set, and a generator set. Background Art

[0002] With the development of the economy, new power systems are being built at an accelerated pace, and new green energy sources such as wind power generation and solar power generation are developing rapidly.

[0003] The main disadvantage of new green energy is its instability. Its power generation capacity is greatly affected by weather factors. The key issue of large-scale access to the power grid is to solve the regulation capacity of the existing power grid. Specifically, the power grid urgently needs to quickly increase the deep peak regulation and rapid frequency regulation capabilities, which is also the basic feature and symbol of the new power system. In this context, the power grid dispatching center has higher and higher requirements for the regulation quality of large and medium-sized units in thermal power plants, requiring the units to achieve stable and safe operation of key parameters during rapid load changes. Therefore, it is necessary to improve the regulation capacity of the coordinated control of the unit. The boiler master control can control the amount of fuel entering the furnace, and control the addition and subtraction of coal by the boiler master control to ensure the stable operation of the key parameters of the unit. The dynamic feedforward control method of the generator set in the prior art cannot adapt to the working conditions of the unit with frequent load changes, and cannot solve the problem of untimely adjustment of coal quantity when the unit load command changes frequently. Summary of the invention

[0004] The present invention provides a dynamic feedforward control method, device and generator set of a coal-fired generator set, so as to match the boiler coal quantity with the actual load energy demand of the unit when the unit changes load rapidly and frequently, and realize accurate control of the main steam pressure of the unit and the unit load.

[0005] In a first aspect, an embodiment of the present invention provides a dynamic feedforward control method for a coal-fired power generation unit, the method comprising:

[0006] Obtain the target load instruction and the load instruction after rate limit of the current generator set;

[0007] Determining a first feedforward quantity function and an inertia time according to a deviation between the target load command and the rate-limited load command;

[0008] Acquire current operating parameters and current setting parameters of the generator set, determine a correction coefficient according to the current operating parameters and the current setting parameters, and correct the first feedforward quantity function according to the correction coefficient to obtain a second feedforward quantity function;

[0009] The deviation between the target load command and the post-rate limit load command is substituted into the second feedforward function to obtain the boiler master control dynamic feedforward, which is output to the boiler master of the generator set after the inertia time to adjust the fuel quantity of the unit.

[0010] Optionally, determining the first feedforward function and the inertia time according to the deviation between the target load command and the rate-limited load command includes:

[0011] Determining the load state of the boiler master control according to the deviation between the target load command and the load command after the rate limit, and selecting the first feedforward function according to the load state of the boiler master control;

[0012] The inertia time is determined according to a deviation between the target load command and the rate-limited post-load command.

[0013] Optionally, determining the load state of the boiler master control according to the deviation between the target load command and the load command after rate limiting, and selecting the first feedforward function according to the load state of the boiler master control includes:

[0014] Determining the load state of the boiler master control according to the deviation between the target load command and the post-rate limit load command;

[0015] When the load state of the boiler master control is load increase, selecting the load increase function of the generator set as the first feedforward quantity function;

[0016] When the load state of the boiler master control is load reduction, the load reduction function of the generator set is selected as the first feedforward function.

[0017] Optionally, before determining the load state of the boiler master control according to the deviation between the target load instruction and the load instruction after rate limitation, the method further includes:

[0018] Acquire historical operation data of the generator set in advance;

[0019] A load increase function and a load decrease function of the generator set are determined according to historical operation data of the generator set.

[0020] Optionally, the acquiring current operating parameters and current setting parameters of the generator set, and determining a correction coefficient according to the current operating parameters and the current setting parameters, includes:

[0021] Obtaining the current unit load change rate of the generator set, the current unit main steam pressure setting value, the main steam pressure measurement value and the change rate of the current unit main steam pressure measurement value;

[0022] Determining a first correction coefficient according to a deviation between the current set value of the main steam pressure of the unit and the measured value of the main steam pressure;

[0023] Determining a second correction coefficient according to the current unit load change rate;

[0024] Determining a third correction coefficient according to the change rate of the current measured value of the main steam pressure of the unit;

[0025] A fourth correction coefficient is determined based on the rate-limited afterload command.

[0026] Optionally, the correcting the first feedforward quantity function according to the correction coefficient to obtain a second feedforward quantity function includes:

[0027] Multiplying the first correction coefficient, the second correction coefficient, the third correction coefficient and the fourth correction coefficient to obtain a function correction coefficient;

[0028] The function correction coefficient is multiplied by the first feedforward quantity function to obtain the second feedforward quantity function.

[0029] In a second aspect, an embodiment of the present invention further provides a dynamic feedforward control device for a coal-fired power generation set, wherein the dynamic feedforward control device for the coal-fired power generation set is used to execute the dynamic feedforward control method for the coal-fired power generation set described in any embodiment of the present invention, and the device comprises:

[0030] An acquisition module, used to acquire a target load instruction and a load instruction after rate limiting of the current generator set;

[0031] A function determination module, configured to determine a first feedforward quantity function and an inertia time according to a deviation between the target load instruction and the rate-limited load instruction;

[0032] a function correction module, configured to obtain current operating parameters and current setting parameters of the generator set, determine a correction coefficient according to the current operating parameters and the current setting parameters, and correct the first feedforward quantity function according to the correction coefficient to obtain a second feedforward quantity function;

[0033] The output module is used to substitute the deviation between the target load instruction and the load instruction after the rate limit into the second feedforward function to obtain the boiler master control dynamic feedforward, and output it to the boiler master control of the generator set after the inertia time to adjust the fuel amount of the unit.

[0034] Optionally, the function determination module includes:

[0035] a function determination unit, configured to determine the load state of the boiler master control according to a deviation between the target load command and the load command after rate limiting, and select the first feedforward function according to the load state of the boiler master control;

[0036] The time determination unit is used to determine the inertia time according to the deviation between the target load instruction and the load instruction after the rate limit.

[0037] Optionally, the function determination unit further includes:

[0038] a load determination unit, configured to determine a load state of the boiler master control according to a deviation between the target load instruction and the post-rate-limited load instruction;

[0039] A function selection unit is used to select the load increase function of the generator set as the first feedforward function when the load state of the boiler master control is load increase; and is used to select the load reduction function of the generator set as the first feedforward function when the load state of the boiler master control is load reduction.

[0040] In a third aspect, an embodiment of the present invention further provides a generator set, which includes the dynamic feedforward control device of the coal-fired generator set described in any embodiment of the present invention.

[0041] The present invention provides a dynamic feedforward control method, device and generator set of a coal-fired generator set, which obtains a target load instruction and a rate-limited post-load instruction of the current generator set; determines a first feedforward quantity function and an inertia time according to the deviation between the target load instruction and the rate-limited post-load instruction; obtains the current operating parameters and current setting parameters of the generator set, determines a correction coefficient according to the current operating parameters and the current setting parameters, corrects the first feedforward quantity function according to the correction coefficient, and obtains a second feedforward quantity function; substitutes the deviation between the target load instruction and the rate-limited post-load instruction into the second feedforward quantity function to obtain a boiler master control dynamic feedforward quantity, and outputs it to the boiler master control of the generator set after the inertia time, so as to adjust the fuel quantity of the unit, accurately judge the fuel quantity required to be increased or decreased in the next load change process of the unit, thereby realizing precise control of the main steam pressure of the unit and the load of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 A flow chart of a dynamic feedforward control method for a coal-fired power generation unit provided in an embodiment of the present invention.

[0043] Figure 2 A flow chart for determining a first feedforward function and an inertia time provided by an embodiment of the present invention.

[0044] Figure 3The present invention is a schematic diagram of a boiler master control dynamic feedforward quantity generation method according to an embodiment of the present invention.

[0045] Figure 4 Schematic diagram of the structure of a dynamic feedforward control device for a coal-fired power generation unit in an embodiment of the present invention. DETAILED DESCRIPTION

[0046] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0047] The embodiment of the present invention provides a dynamic feedforward control method for a coal-fired power generation unit. The embodiment is applicable to application scenarios where the coal-fired power generation unit changes load rapidly and frequently. When the coal-fired power generation unit changes load rapidly and frequently, the dynamic feedforward of the boiler master control with coordinated control quality can accurately determine the amount of fuel required to increase or decrease in the next load change process of the unit, thereby achieving precise control of the main steam pressure of the unit and the load of the unit. The method can be executed by a dynamic feedforward control device of a coal-fired power generation unit, and the dynamic feedforward control device of a coal-fired power generation unit can be implemented in the form of hardware and / or software. Figure 1 A flow chart of a dynamic feedforward control method for a coal-fired power generation unit provided by an embodiment of the present invention is as follows: Figure 1 As shown, the dynamic feedforward control method of the coal-fired power generation unit includes:

[0048] S110, obtaining a target load instruction and a post-rate limit load instruction of the current generator set.

[0049] Among them, Automatic Generation Control (AGC) is an important function in the energy management system. It controls the output of the frequency-modulated units to meet the ever-changing power needs of users and keep the system in an economical operating state. In the power system, AGC is a system that adjusts the active output of multiple generators in different power plants in response to load changes. The target load instruction is the AGC instruction. In the power system, AGC is a system that adjusts the active output of multiple generators in different power plants in response to load changes. The power generation instruction issued by the AGC system is called the AGC instruction. The load instruction after rate limit means that the generator set sends it to each control system (boiler master control, steam turbine master control, etc.) through a certain rate limit after obtaining the target load instruction (AGC instruction).

[0050] Specifically, when the AGC command produces a step-like change, the boiler master control dynamic feedforward control loop will form the boiler master control dynamic feedforward amount through the function generator according to the deviation between the target load command of the generator set and the load command after the rate limit, and the variable load dynamic feedforward of some units is corrected by the command change amplitude. Therefore, by obtaining the target load command and the load command after the rate limit of the current generator set, in order to select the function, the dynamic feedforward amount of the boiler master control is confirmed.

[0051] S120: Determine a first feedforward function and an inertia time according to a deviation between the target load command and the load command after the rate limit.

[0052] Specifically, at present, most of the coordinated control systems of thermal power generating units adopt a coordinated control method based on boiler tracking. Due to the large delay and large inertia on the boiler side, additional supplementation and release of boiler energy storage are required when increasing or decreasing the load of the unit. Therefore, the process of increasing or decreasing the load of the generating unit can be determined by the deviation between the target load instruction and the load instruction after the rate limit, and then the preset load increase function or load decrease function is selected for load increase or load decrease as the first feedforward function, which is the boiler main control dynamic feedforward function, and then the boiler main control dynamic feedforward control loop is established; and the dynamic response time of the boiler main control dynamic feedforward control loop is determined by the deviation between the target load instruction and the load instruction after the rate limit, as the inertia time, so as to improve the dynamic response of the boiler, and realize the initial value amplitude of the dynamic feedforward when the load is changed and the time point of the dynamic control feedforward braking.

[0053] S130, obtaining current operating parameters and current setting parameters of the generator set, determining a correction coefficient according to the current operating parameters and the current setting parameters, and correcting the first feedforward function according to the correction coefficient to obtain a second feedforward function.

[0054] Specifically, by acquiring the current operating parameters and current setting parameters of the generator set, the current operating parameters and the current setting parameters of the generator set are compared, so that the correction coefficient can be determined according to the current operating parameters and the current setting parameters. Exemplarily, the current operating parameters may include parameters such as the main steam pressure measurement value and the current unit load change rate, and the current setting parameters may include parameters such as the main steam pressure setting value. The correction coefficient of the first feedforward function is determined according to the deviation between the current generator set main steam pressure setting value and the main steam pressure measurement value, and the first feedforward function is corrected according to the correction coefficient. The correction coefficient can be used as the coefficient of the first feedforward function to obtain a second feedforward function as a corrected boiler master control dynamic feedforward function. The boiler master control dynamic feedforward obtained by the corrected boiler master control dynamic feedforward function is more accurate, thereby improving the control effect of the boiler master control dynamic feedforward function.

[0055] S140, substituting the deviation between the target load command and the load command after the rate limit into the second feedforward function to obtain the boiler master control dynamic feedforward, and outputting it to the boiler master control of the generator set after the inertia time to adjust the fuel amount of the unit.

[0056] Among them, the boiler master control is the boiler controller in the coordinated control system of the generator set, which is mainly responsible for the unit coal feed control and steam pressure deviation control. The dynamic feedforward of the boiler master control is based on a known interference model or load demand change. It predicts the deviation that may occur in the future and adjusts the controller output in advance accordingly. A control parameter. In an embodiment of the present invention, the dynamic feedforward of the boiler master control can be obtained by substituting the deviation of the target load instruction and the load instruction after the rate limit into the second feedforward function, so as to predict and compensate for the interference or disturbance that may occur in the boiler control system in the future in advance, improve the robustness and stability of the boiler control system, speed up the response speed of the boiler to load changes, improve the dynamic performance of the system, improve the control accuracy and efficiency of the boiler control system, and improve the adjustment ability of the coordinated control of the unit. The coordinated control of the unit is the process of issuing instructions to the boiler automatic control system and the steam turbine automatic control system at the same time, so as to achieve the purpose of rapid response to load changes, maximize the frequency regulation and peak regulation capabilities of the unit, and stabilize the operating parameters. The fuel quantity of the unit and the main steam pressure of the unit

[0057] Specifically, the deviation between the target load command and the load command after the rate limit is substituted into the second feedforward function, and the amount of fuel that needs to be increased or decreased in the load change process of the unit at the next moment is accurately determined, and the boiler master control dynamic feedforward is obtained. After the inertia time, the boiler master control dynamic feedforward is output to the boiler master control of the generator set to adjust the unit fuel amount, thereby the unit load. At the same time, the unit main steam pressure is related to the unit load, and the unit main steam pressure changes with the unit load. Therefore, by accurately determining the amount of fuel that needs to be increased or decreased in the load change process of the unit at the next moment and adjusting the unit fuel amount, precise control of the unit main steam pressure and unit load can be achieved.

[0058] It should be noted that the dynamic feedforward control method of the coal-fired generator set provided in the embodiment of the present invention can be used as a frequency regulation auxiliary service in the power system. The frequency regulation auxiliary service is a very important service in the power system. Its main purpose is to ensure the safe and reliable operation of the power system and ensure the quality of electric energy by maintaining the frequency stability of the power grid. When the actual frequency of the power system deviates from the predetermined target frequency, the frequency regulation auxiliary service will be activated to reduce this deviation by adjusting the active output of the generator.

[0059] The embodiment of the present invention provides a dynamic feedforward control method for a coal-fired power generation unit, which obtains a target load instruction and a rate-limited post-load instruction of the current power generation unit; determines a first feedforward quantity function and an inertia time according to the deviation between the target load instruction and the rate-limited post-load instruction; obtains the current operating parameters and current setting parameters of the power generation unit, determines a correction coefficient according to the current operating parameters and the current setting parameters, corrects the first feedforward quantity function according to the correction coefficient, and obtains a second feedforward quantity function; substitutes the deviation between the target load instruction and the rate-limited post-load instruction into the second feedforward quantity function to obtain a boiler master control dynamic feedforward quantity, and outputs it to the boiler master control of the power generation unit after the inertia time, so as to adjust the fuel quantity of the unit, and accurately judge the fuel quantity required to be increased or decreased in the next load change process of the unit, thereby realizing precise control of the main steam pressure of the unit and the load of the unit.

[0060] In order to further realize the precise control of the main steam pressure and load of the unit, the embodiment of the present invention provides a specific process for determining the first feedforward function and the inertia time. Figure 2 A flowchart for determining the first feedforward function and the inertia time provided by an embodiment of the present invention, such as Figure 2 As shown, the first feedforward function and the inertia time are determined according to the deviation between the target load command and the load command after the rate limit, including:

[0061] S210, determining the load state of the boiler master control according to the deviation between the target load command and the load command after rate limitation, and selecting a first feedforward function according to the load state of the boiler master control.

[0062] Specifically, the load state of the boiler master control is determined according to the deviation between the target load instruction and the load instruction after the rate limit. The load state of the boiler master control is divided into load increase and load decrease. Different load states of different boiler masters correspond to different functions. The corresponding function is selected as the first feedforward function according to the load state of the boiler master control.

[0063] Optionally, determining the load state of the boiler master control according to the deviation between the target load command and the load command after the rate limit, and selecting the first feedforward quantity function according to the load state of the boiler master control include:

[0064] The load state of the boiler master control is determined according to the deviation between the target load command and the load command after the rate limit; when the load state of the boiler master control is load increase, the load increase function of the generator set is selected as the first feedforward function; when the load state of the boiler master control is load reduction, the load reduction function of the generator set is selected as the first feedforward function.

[0065] Among them, according to the deviation between the load command after the current unit rate limit and the target load command, it can be determined whether the generator set is executing the process of increasing or decreasing the load. For example, when the deviation is greater than 0, the generator set is executing the process of increasing the load, and when the deviation is less than 0, the generator set is executing the process of decreasing the load. The load increase function and load decrease function of the generator set are both dynamic feedforward functions of the boiler master control. The function between the dynamic feedforward of the boiler master control and the load deviation can be determined by collecting data from the historical curve of the generator set operation. When the load state of the boiler master control is increasing the load, the load increase function of the generator set is selected as the first feedforward function; when the load state of the boiler master control is decreasing the load, the load decrease function of the generator set is selected as the first feedforward function, so as to distinguish the load increase and load decrease processes of the boiler master control, and then realize the precise control of the unit load.

[0066] Optionally, before determining the load state of the boiler master control according to the deviation between the target load instruction and the load instruction after the rate limit, the method further includes:

[0067] Acquire historical operating data of the generator set in advance; determine a load increase function and a load decrease function of the generator set according to the historical operating data of the generator set.

[0068] Specifically, the deviation between the current unit's load command after rate limit and the target load command is used to determine whether the unit is in a load increase or decrease process at the next moment, thereby selecting a load increase function or a load decrease function as the first feedforward function (boiler master control dynamic feedforward function).

[0069] S220: Determine the inertia time according to the deviation between the target load command and the load command after the rate limit.

[0070] Specifically, the inertia time of the boiler master control dynamic feedforward quantity function is determined according to the deviation between the load command after the current unit speed limit and the target load command.

[0071] In the embodiment of the present invention, in order to improve the precise control of the main steam pressure and the load of the unit, the current operating parameters and the current setting parameters of the generator set are obtained, and the correction coefficient is determined according to the current operating parameters and the current setting parameters, which specifically includes:

[0072] Obtain the current unit load change rate of the generator set, the current unit main steam pressure setting value, the main steam pressure measurement value and the change rate of the current unit main steam pressure measurement value.

[0073] The first correction coefficient a is determined according to the deviation between the current set value of the main steam pressure of the unit and the measured value of the main steam pressure.

[0074] The second correction coefficient b is determined according to the current rate of change of the unit load.

[0075] The third correction coefficient c is determined according to the rate of change of the current measured value of the main steam pressure of the unit.

[0076] A fourth correction coefficient d is determined according to the rate-limited afterload command.

[0077] Among them, the current unit load change rate is the rate at which the generator unit changes from the current load to the target load at a certain rate after receiving the target load instruction of the AGC. The current unit main steam pressure setting value is the steam pressure setting value before the turbine nozzle valve. The main steam pressure setting value is used as the inlet deviation of the boiler main control PID after the difference between the main steam pressure measurement value. The main steam pressure measurement value is the steam pressure before the turbine nozzle valve.

[0078] Specifically, the first correction coefficient a can be determined by substituting the deviation between the current unit main steam pressure setting value and the main steam pressure measurement value into the correction function established in advance according to the historical operation data, the second correction coefficient b can be determined by substituting the current unit load change rate into the correction function established in advance according to the historical operation data, the third correction coefficient c can be determined by substituting the current unit main steam pressure measurement value into the correction function established in advance according to the historical operation data, and the fourth correction coefficient d can be determined by substituting the current unit main steam pressure setting value into the correction function established in advance according to the historical operation data according to the rate-limited load instruction. The first feedforward quantity function is corrected by the first correction coefficient a, the second correction coefficient b, the third correction coefficient c and the fourth correction coefficient d to obtain the second feedforward quantity function, so as to accurately judge the amount of fuel required to increase or decrease in the next moment of the unit load change process according to the second feedforward quantity function, and obtain the boiler master control dynamic feedforward quantity, and output the boiler master control dynamic feedforward quantity to the boiler master control of the generator set after the inertia time to adjust the unit fuel quantity, thereby realizing the precise control of the unit main steam pressure and unit load.

[0079] Furthermore, the first feedforward quantity function is corrected according to the correction coefficient to obtain a second feedforward quantity function, including:

[0080] The first correction coefficient, the second correction coefficient, the third correction coefficient and the fourth correction coefficient are multiplied to obtain the function correction coefficient.

[0081] The function correction coefficient is multiplied by the first feedforward quantity function to obtain the second feedforward quantity function.

[0082] Specifically, the first correction coefficient, the second correction coefficient, the third correction coefficient and the fourth correction coefficient are multiplied to obtain a function correction coefficient, and the first feedforward function is corrected by multiplying the function correction coefficient obtained by the first correction coefficient, the second correction coefficient, the third correction coefficient and the fourth correction coefficient, and finally a new boiler master control dynamic feedforward function is obtained as the second feedforward function.

[0083] In addition, to further explain the control process of the dynamic feedforward control method of the coal-fired generator set, Figure 3 FIG. 1 is a schematic diagram of generating a boiler master control dynamic feedforward quantity in an embodiment of the present invention, such as Figure 3 As shown, Figure 3 The CPC includes two control loops, namely the load increase control loop and the load decrease control loop. Both the load increase control loop and the load decrease control loop can generate the boiler main control dynamic feedforward quantity. Figure 3 As shown, after obtaining the target load instruction, load change rate, main steam pressure setting value, main steam pressure measurement value and rate-limited post-load instruction of the current unit of the generator set, the deviation between the target load instruction and the rate-limited post-load instruction is calculated by the subtraction block, and the process of whether the current unit will increase or decrease the load is determined according to the deviation between the target load instruction and the rate-limited post-load instruction, and then the load increase control loop or the load decrease control loop is selected, thereby selecting the boiler master control dynamic feedforward quantity increase function or the boiler master control dynamic feedforward quantity increase function as the first feedforward quantity function, and determining the boiler master control dynamic feedforward quantity inertia time or the boiler master control dynamic feedforward inertia time according to the deviation between the target load instruction and the rate-limited post-load instruction. At the same time, the second correction coefficient b can be determined according to the current unit load change rate and a pre-established function; the fourth correction coefficient d can be determined according to the rate-limited post-load instruction and a pre-established function; the deviation between the main steam pressure setting value and the main steam pressure measurement value is obtained by substituting the main steam pressure measurement value into the subtraction block for calculation, and the first correction coefficient a is determined by the deviation between the main steam pressure setting value and the main steam pressure measurement value and a pre-established function; the change rate of the main steam pressure measurement value of the current unit is obtained by substituting the main steam pressure measurement value into the differential block for differential calculation, and the third correction coefficient c is determined according to the change rate of the main steam pressure measurement value of the current unit. The first correction coefficient a, the second correction coefficient b, the third correction coefficient c and the fourth correction coefficient d are multiplied by multiple multiplication blocks, and then calculated with the boiler master control dynamic feedforward quantity load increase function or the boiler master control dynamic feedforward quantity load increase function (i.e., the first feedforward quantity function) through the multiplication block to obtain the corrected boiler master control dynamic feedforward quantity load increase function or the boiler master control dynamic feedforward quantity load increase function (i.e., the second feedforward quantity function). The boiler master control dynamic feedforward quantity obtained by inputting the boiler master control dynamic feedforward quantity load increase function or the boiler master control dynamic feedforward quantity load increase function and the corresponding inertia time into the inertia block is output to the boiler master of the generator set to adjust the fuel amount of the unit. In addition, the deviation between the target load command and the load command after the rate limit can determine whether the unit is in the process of increasing or decreasing the load at the next moment, and then different control loops are selected through the switching block. In addition, Figure 3The high and low limit blocks in the program can set the upper and lower limits of the deviation between the target load command and the load command after the rate limit. When the deviation between the target load command and the load command after the rate limit exceeds the upper or lower limit, the boiler master control dynamic feedforward amount is calculated directly based on the deviation between the target load command and the load command after the rate limit.

[0084] The dynamic feedforward coordinated control method of thermal power units in the prior art cannot effectively solve the problem of untimely adjustment of coal quantity when the unit load command changes frequently, and the problem of large-scale fluctuations in main steam pressure. In addition, there is a lack of judgment and correction of the main steam pressure change trend, and it cannot adapt to the working conditions of frequent load changes of the unit. Under the working conditions of frequent load changes of the unit, boiler overpressure and underpressure will often occur. The core control idea of ​​the embodiment of the present invention to solve the existing problems is to correct the dynamic feedforward amount of the boiler main control by the main steam pressure deviation and the main steam pressure change slope, so that the boiler coal quantity and the actual load energy demand of the unit are matched when the unit changes load rapidly and frequently, improving the problem of large fluctuations in the main steam pressure, and at the same time, it can improve the control effect of the core parameters of the unit such as the main steam, reheat steam and boiler tube wall temperature.

[0085] The embodiment of the present invention provides a dynamic feedforward control method for a coal-fired power generation unit, which accurately determines the amount of fuel required to be increased or decreased during the load change process of the unit at the next moment by calculating the deviation between the main steam pressure of the unit at the current moment and the set value and the slope of the main steam pressure change, thereby realizing precise control of the main steam pressure of the unit and the load of the unit. The present invention can match the amount of boiler coal with the actual load energy demand of the unit when the generator unit changes load rapidly and frequently, improve the problem of large fluctuations in the main steam pressure, and at the same time improve the control effect of core parameters such as the main steam, reheat steam and boiler tube wall temperature of the unit.

[0086] The embodiment of the present invention also provides a dynamic feedforward control device for a coal-fired power generation unit. Figure 4 Schematic diagram of the structure of a dynamic feedforward control device of a coal-fired power generation set in an embodiment of the present invention. The dynamic feedforward control device of a coal-fired power generation set in an embodiment of the present invention is used to execute the dynamic feedforward control method of a coal-fired power generation set in any embodiment of the present invention, such as Figure 4 As shown, the dynamic feedforward control device of the coal-fired power generation unit includes:

[0087] An acquisition module 110 is used to acquire a target load instruction and a load instruction after rate limiting of a current generator set;

[0088] A function determination module 120, for determining a first feedforward quantity function and an inertia time according to a deviation between a target load instruction and a load instruction after a rate limit;

[0089] The function correction module 130 is used to obtain the current operating parameters and the current setting parameters of the generator set, determine the correction coefficient according to the current operating parameters and the current setting parameters, and correct the first feedforward quantity function according to the correction coefficient to obtain the second feedforward quantity function;

[0090] The output module 140 is used to substitute the deviation between the target load command and the load command after the rate limit into the second feedforward function to obtain the boiler master control dynamic feedforward, which is output to the boiler master of the generator set after the inertia time to adjust the fuel quantity of the unit.

[0091] Specifically, the acquisition module 110 obtains the target load instruction and the load instruction after the rate limit of the current generator set in order to select a function, thereby confirming the dynamic feedforward amount of the boiler master control. The function determination module 120 can determine whether the generator set is to increase or decrease the load according to the deviation between the target load instruction and the load instruction after the rate limit, and then selects the preset load increase function or load decrease function as the first feedforward amount function, which is the dynamic feedforward amount function of the boiler master control. The function correction module 130 obtains the current operating parameters and current setting parameters of the generator set, compares the current operating parameters and the current setting parameters of the generator set, and thereby determines a correction coefficient based on the current operating parameters and the current setting parameters. Exemplarily, the current operating parameters may include parameters such as the main steam pressure measurement value and the current unit load change rate, and the current setting parameters may include parameters such as the main steam pressure setting value. The correction coefficient of the first feedforward function is determined based on the deviation between the current generator set main steam pressure setting value and the main steam pressure measurement value, and the first feedforward function is corrected based on the correction coefficient. The correction coefficient may be used as the coefficient of the first feedforward function to obtain a second feedforward function as a corrected boiler master control dynamic feedforward function. The boiler master control dynamic feedforward obtained through the corrected boiler master control dynamic feedforward function is more accurate, thereby improving the control effect of the boiler master control dynamic feedforward function. The output module 140 substitutes the deviation between the target load command and the load command after the rate limit into the second feedforward function, accurately determines the amount of fuel required to increase or decrease in the unit's load change process at the next moment, obtains the boiler master control dynamic feedforward, and outputs the boiler master control dynamic feedforward to the boiler master of the generator unit after the inertia time to adjust the unit's fuel quantity, thereby achieving precise control of the unit's main steam pressure and unit load.

[0092] The embodiment of the present invention provides a dynamic feedforward control device for a coal-fired power generation set, wherein an acquisition module acquires a target load instruction and a rate-limited post-load instruction of the current power generation set; a function determination module determines a first feedforward quantity function and an inertia time according to a deviation between the target load instruction and the rate-limited post-load instruction; a function correction module acquires current operating parameters and current setting parameters of the power generation set, determines a correction coefficient according to the current operating parameters and the current setting parameters, and corrects the first feedforward quantity function according to the correction coefficient to obtain a second feedforward quantity function; an output module substitutes the deviation between the target load instruction and the rate-limited post-load instruction into the second feedforward quantity function to obtain a boiler master control dynamic feedforward quantity, and outputs it to the boiler master control of the power generation set after the inertia time, so as to adjust the fuel quantity of the unit, accurately determine the fuel quantity required to be increased or decreased in the next load change process of the unit, thereby realizing precise control of the main steam pressure of the unit and the load of the unit.

[0093] Optionally, the function determination module includes:

[0094] The function determination unit is used to determine the load state of the boiler master control according to the deviation between the target load command and the load command after the rate limit, and select the first feedforward function according to the load state of the boiler master control.

[0095] The time determination unit is used to determine the inertia time according to the deviation between the target load instruction and the load instruction after the speed limit.

[0096] Specifically, the function determination unit determines the load state of the boiler master control according to the deviation between the target load command and the load command after the rate limit. The load state of the boiler master control is divided into load increase and load decrease. Different functions correspond to different load states of the boiler master control. The corresponding function is selected as the first feedforward function according to the load state of the boiler master control. The time determination unit determines the inertia time by substituting the deviation between the target load command and the load command after the rate limit into the pre-established function, so as to cooperate with the characteristics of large delay and large inertia on the boiler side to improve the precise control of the unit load.

[0097] Optionally, the function determination unit further includes:

[0098] The load determination unit is used to determine the load state of the boiler master control according to the deviation between the target load instruction and the load instruction after the rate limit.

[0099] The function selection unit is used to select the load increase function of the generator set as the first feedforward function when the load state of the boiler master control is load increase; and is used to select the load reduction function of the generator set as the first feedforward function when the load state of the boiler master control is load reduction.

[0100] Specifically, the load determination unit can determine whether the generator set is performing a load increase or load decrease process based on the deviation between the load command after the current unit rate limit and the target load command. For example, when the deviation is greater than 0, the generator set is performing a load increase process, and when the deviation is less than 0, the generator set is performing a load decrease process. When the load state of the boiler master control is load increase, the function selection unit selects the load increase function of the generator set as the first feedforward function; when the load state of the boiler master control is load decrease, the load decrease function of the generator set is selected as the first feedforward function, thereby distinguishing the load increase and load decrease processes of the boiler master control, and then realizing precise control of the unit load. In addition, the function selection unit can determine the load increase function and load decrease function of the generator set based on the historical operation data of the generator set by acquiring the historical operation data of the generator set in advance.

[0101] In addition, the dynamic feedforward control device of the coal-fired generator set in the embodiment of the present invention includes but is not limited to the above modules. The dynamic feedforward control device of the coal-fired generator set in the embodiment of the present invention can adaptively set relevant functional modules according to the dynamic feedforward control device of the coal-fired generator set in any embodiment of the present invention to achieve the function and technical effect of the dynamic feedforward control device of the coal-fired generator set in any embodiment of the present invention.

[0102] An embodiment of the present invention further provides a generator set, comprising the dynamic feedforward control device of the coal-fired generator set in the above embodiment, thereby realizing the function and technical effect of the dynamic feedforward control device of the coal-fired generator set in the above embodiment.

[0103] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A dynamic feedforward control method for a coal-fired power generation unit, characterized in that: The method comprises: Obtain the target load instruction and the load instruction after rate limit of the current generator set; Determining a first feedforward quantity function and an inertia time according to a deviation between the target load command and the rate-limited load command; Acquire current operating parameters and current setting parameters of the generator set, determine a correction coefficient according to the current operating parameters and the current setting parameters, and correct the first feedforward quantity function according to the correction coefficient to obtain a second feedforward quantity function; The deviation between the target load command and the post-rate limit load command is substituted into the second feedforward function to obtain the boiler master control dynamic feedforward, which is output to the boiler master of the generator set after the inertia time to adjust the fuel quantity of the unit.

2. The dynamic feedforward control method of a coal-fired power generation unit according to claim 1, characterized in that: The step of determining the first feedforward quantity function and the inertia time according to the deviation between the target load instruction and the rate-limited load instruction comprises: Determining the load state of the boiler master control according to the deviation between the target load command and the load command after the rate limit, and selecting the first feedforward function according to the load state of the boiler master control; The inertia time is determined according to a deviation between the target load command and the rate-limited post-load command.

3. The dynamic feedforward control method of a coal-fired power generation unit according to claim 2, characterized in that: The step of determining the load state of the boiler master control according to the deviation between the target load command and the load command after the rate limit, and selecting the first feedforward function according to the load state of the boiler master control includes: Determining the load state of the boiler master control according to the deviation between the target load command and the post-rate limit load command; When the load state of the boiler master control is load increase, selecting the load increase function of the generator set as the first feedforward quantity function; When the load state of the boiler master control is load reduction, the load reduction function of the generator set is selected as the first feedforward function.

4. The dynamic feedforward control method of a coal-fired power generation unit according to claim 3, characterized in that: Before determining the load state of the boiler master control according to the deviation between the target load command and the load command after rate limit, the method further includes: Acquire historical operation data of the generator set in advance; A load increase function and a load decrease function of the generator set are determined according to historical operation data of the generator set.

5. The dynamic feedforward control method of a coal-fired power generation unit according to claim 1, characterized in that: The obtaining of the current operating parameters and the current setting parameters of the generator set, and determining the correction coefficient according to the current operating parameters and the current setting parameters, comprises: Obtaining the current unit load change rate of the generator set, the current unit main steam pressure setting value, the main steam pressure measurement value and the change rate of the current unit main steam pressure measurement value; Determining a first correction coefficient according to a deviation between the current set value of the main steam pressure of the unit and the measured value of the main steam pressure; Determining a second correction coefficient according to the current unit load change rate; Determining a third correction coefficient according to the change rate of the current measured value of the main steam pressure of the unit; A fourth correction coefficient is determined based on the rate-limited afterload command.

6. The dynamic feedforward control method of a coal-fired power generation unit according to claim 5, characterized in that: The step of correcting the first feedforward quantity function according to the correction coefficient to obtain a second feedforward quantity function includes: Multiplying the first correction coefficient, the second correction coefficient, the third correction coefficient and the fourth correction coefficient to obtain a function correction coefficient; The function correction coefficient is multiplied by the first feedforward quantity function to obtain the second feedforward quantity function.

7. A dynamic feedforward control device for a coal-fired power generation unit, characterized in that: The dynamic feedforward control device of the coal-fired power generation set is used to execute the dynamic feedforward control method of the coal-fired power generation set according to any one of claims 1 to 6, and the device comprises: An acquisition module, used to acquire a target load instruction and a load instruction after rate limiting of the current generator set; A function determination module, configured to determine a first feedforward quantity function and an inertia time according to a deviation between the target load instruction and the rate-limited load instruction; a function correction module, configured to obtain current operating parameters and current setting parameters of the generator set, determine a correction coefficient according to the current operating parameters and the current setting parameters, and correct the first feedforward quantity function according to the correction coefficient to obtain a second feedforward quantity function; The output module is used to substitute the deviation between the target load instruction and the load instruction after the rate limit into the second feedforward function to obtain the boiler master control dynamic feedforward, and output it to the boiler master control of the generator set after the inertia time to adjust the fuel amount of the unit.

8. The dynamic feedforward control device for a coal-fired power generation unit according to claim 7, characterized in that: The function determination module comprises: a function determination unit, configured to determine the load state of the boiler master control according to a deviation between the target load command and the load command after rate limiting, and select the first feedforward function according to the load state of the boiler master control; The time determination unit is used to determine the inertia time according to the deviation between the target load instruction and the rate-limited post-load instruction.

9. The dynamic feedforward control device for a coal-fired power generation unit according to claim 8, characterized in that: The function determination unit also includes: a load determination unit, configured to determine a load state of the boiler master control according to a deviation between the target load instruction and the post-rate-limited load instruction; A function selection unit is used to select the load increase function of the generator set as the first feedforward function when the load state of the boiler master control is load increase; and is used to select the load reduction function of the generator set as the first feedforward function when the load state of the boiler master control is load reduction.

10. A generator set, characterized in that: The generator set comprises the dynamic feedforward control device of the coal-fired generator set as described in any one of claims 7 to 9 above.

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