Primary frequency modulation control method and system for thermal power plant

Abstract

The application relates to a primary frequency modulation control method of a thermal power plant, wherein the method is applied to a gas-steam combined cycle unit, and the method comprises the following steps: on the gas turbine side: acquiring a power grid frequency, performing signal optimization processing on the power grid frequency through a same-source frequency modulation device, and performing primary frequency modulation logic operation on the gas turbine to obtain a frequency modulation output instruction, wherein the same-source frequency modulation device is constructed based on a grid-source coordinated controller; and on the steam turbine side: connecting an electric energy storage device to the steam turbine, and performing primary frequency modulation on the steam turbine through the electric energy storage device, wherein the frequency modulation output instruction of the electric energy storage device is determined according to real-time frequency deviation of the power grid and working condition data of the steam turbine. Through the application, the control of the gas side and the steam turbine side is decoupled, and the problem that the load regulation margin of the combined cycle unit is limited and cannot meet the primary frequency modulation examination requirement in the related art is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of power system frequency modulation control, in particular to a primary frequency modulation control method and system for a thermal power plant. BACKGROUND

[0002] With the gradual grid connection of new energy units, the proportion of conventional generating units continues to decline. Since new energy units do not have frequency response capability, the overall frequency response capability of the power system is also gradually weakened. Therefore, only the frequency response capability of conventional thermal power plants can be improved. Consequently, each local power grid has proposed specific primary frequency modulation assessment methods for thermal power plants.

[0003] Traditional gas-fired thermal power plants generally use gas-steam combined cycle units. Due to the complex coupling characteristics between the gas turbine and the steam turbine in the combined cycle unit, personnel cannot accurately control the frequency output of the gas turbine and the steam turbine, increasing the complexity of primary frequency modulation. Further, the steam turbine in the combined cycle unit is usually in a sliding pressure operation state, and it does not have the ability to quickly respond to load changes. Therefore, primary frequency modulation is mainly performed by the gas turbine.

[0004] In related technologies, when primary frequency modulation is performed, the gas turbine adds or reduces the fuel quantity corresponding to the theoretical load variation according to the unequal rate set by the system to quickly realize load variation of the unit, so as to complete the primary frequency modulation process. However, in the primary frequency modulation process, the speed signal is used in the primary frequency modulation logic of the gas turbine system, which has a certain error with the grid frequency. Therefore, it is impossible to ensure synchronization with the grid frequency acquisition data, which seriously affects the primary frequency modulation effect.

[0005] Due to the above reasons, the load regulation margin of the traditional combined cycle unit is limited, and it is increasingly unable to meet the growing demand for primary frequency modulation assessment. SUMMARY

[0006] Embodiments of the present application provide a primary frequency modulation control method and system for a thermal power plant, a computer device and a computer readable storage medium to at least solve the problem of limited load regulation margin of the combined cycle unit in related technologies, which cannot meet the demand for primary frequency modulation assessment.

[0007] In a first aspect, embodiments of the present application provide a primary frequency modulation control method for a thermal power plant, applied to a gas-steam combined cycle unit, the method comprising:

[0008] On the gas turbine side: acquiring a grid frequency, performing signal optimization processing on the grid frequency through a same-source frequency modulation device, performing primary frequency modulation logic operation of the gas turbine using the grid frequency after the signal optimization processing to obtain a frequency modulation output instruction of the gas turbine, wherein the same-source frequency modulation device is constructed based on a grid-source coordinated controller;

[0009] On the steam turbine side: introducing an electric energy storage device into the steam turbine, and using the electric energy storage device to cooperate with the steam turbine to perform primary frequency modulation, wherein the frequency modulation output instruction of the electric energy storage device is determined according to the real-time frequency deviation of the power grid and the working condition data of the steam turbine.

[0010] In some embodiments, on the gas turbine side, the method further comprises:

[0011] By increasing the proportion of the feedforward action on the gas turbine side in the control loop of the combined cycle unit, the response speed of the primary frequency modulation of the gas turbine is improved.

[0012] By configuring a segmented unequal rate and integrating the inertia change of the primary frequency modulation load increment, the 15s response index, the 30s response index and the integral power index in the primary frequency modulation process are improved.

[0013] In some embodiments, on the gas turbine side, the method further comprises:

[0014] The frequency signal is collected from the PMU unit, and different action amplitudes are configured for different frequency deviation parameters of the power grid according to the frequency signal;

[0015] The frequency deviation parameters with the configured action amplitudes are used to participate in frequency modulation operation to obtain a frequency modulation signal.

[0016] The frequency modulation signal is sent to the TCS system and the DEH system to indicate the correct action and filter noise of the primary frequency modulation.

[0017] In some embodiments, before introducing the electric energy storage device into the steam turbine, the method further comprises:

[0018] According to the frequency of the power grid and the power-frequency characteristic, the required power for primary frequency modulation is calculated;

[0019] The duration of the primary frequency modulation is obtained, and the power and capacity of the electric energy storage device to be introduced are determined according to the duration of the primary frequency modulation and the required power for the primary frequency modulation.

[0020] In some embodiments, data transmission is performed between the coordination controller of the electric energy storage device and the EMS system through network communication.

[0021] The working condition data of the steam turbine is transmitted to the EMS system thereof through a hard connection.

[0022] The EMS system of the electric energy storage device obtains the frequency of the power grid through network communication.

[0023] In some embodiments, the primary frequency modulation performed by the electric energy storage device in cooperation with the steam turbine comprises:

[0024] The EMS system of the electric energy storage device calculates the frequency modulation output power in real time according to the real-time frequency deviation data of the power grid and the working condition data of the steam turbine, and sends the frequency modulation output power to the coordination controller of the electric energy storage device.

[0025] The coordination controller performs energy distribution on the frequency modulation output power, and sends a plurality of power control signals obtained by energy distribution to each PCS unit of the electric energy storage device, so as to control the output power of each battery cluster.

[0026] In some embodiments, in the process of performing primary frequency modulation by the electric energy storage device in cooperation with the steam turbine, the method further comprises:

[0027] detecting the real-time frequency on the bus of the electric energy storage device by a frequency detection device, and dynamically adjusting the active power of the electric energy storage device according to the real-time frequency,

[0028] wherein, in the case that the real-time frequency is detected to be out of the dead zone, the coordination controller calculates a compensation value of the active power according to the current working condition and the real-time frequency, and corrects the active power by using the compensation value.

[0029] In a second aspect, the embodiments of the present application provide a primary frequency modulation control system of a thermal power plant, which is applied to a gas-steam combined cycle unit, and the system comprises a same-source frequency modulation device and an electric energy storage device, wherein,

[0030] The same-source frequency modulation device is configured to acquire the power grid frequency on the gas turbine side, and perform signal optimization processing on the power grid frequency, and perform primary frequency modulation logic operation on the gas turbine by using the power grid frequency after the signal optimization processing to obtain the frequency modulation output instruction of the gas turbine, wherein the same-source frequency modulation device is constructed based on a grid-source coordination controller.

[0031] The electric energy storage device is configured to access the steam turbine on the steam turbine side, and perform primary frequency modulation in cooperation with the steam turbine, wherein the frequency modulation output instruction of the electric energy storage device is determined according to the real-time frequency deviation of the power grid and the working condition data of the steam turbine.

[0032] In a third aspect, the embodiments of the present application provide a computer device, which comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the method of the first aspect when executing the computer program.

[0033] In a fourth aspect, the embodiments of the present application provide a computer readable storage medium, which stores a computer program, and the program is executable on a processor to implement the method of the first aspect.

[0034] Compared with the related art, the primary frequency modulation control method of the thermal power plant provided in the embodiments of the present application is applied to a gas-steam combined cycle unit, through the following steps on the gas turbine side: obtaining a power grid frequency, performing signal optimization processing on the power grid frequency through a same-source frequency modulation device, performing a primary frequency modulation logic operation on the gas turbine by using the power grid frequency after the signal optimization processing to obtain a frequency modulation output instruction of the gas turbine; and through the following steps on the steam turbine side: introducing an electric energy storage device to access the steam turbine, and performing primary frequency modulation by the electric energy storage device in cooperation with the steam turbine. The problem that the load regulation margin of the combined cycle unit is limited and cannot meet the demand of primary frequency modulation examination in the related art is solved. In the embodiments, the control of the gas side and the steam turbine side is decoupled, the gas turbine side uses the same-source frequency modulation device to improve the primary frequency modulation performance, and the steam turbine side introduces the electric energy storage device to assist the steam turbine in frequency modulation, thereby improving the load response capability. Overall, the load regulation margin of the combined cycle unit is improved, and the risk of the thermal power plant being warned by the primary frequency modulation examination is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0035] The accompanying drawings, which are included to provide a further understanding of the present application, form a part of the present application and illustrate the illustrative embodiments of the present application and together with the description serve to explain the present application. In the drawings:

[0036] Figure 1 is a structural schematic diagram of a gas-steam combined cycle unit according to the embodiments of the present application;

[0037] Figure 2 is a schematic diagram of a gas-steam combined cycle unit according to the embodiments of the present application;

[0038] Figure 3 is a flowchart of a primary frequency modulation control method of a thermal power plant according to the embodiments of the present application;

[0039] Figure 4 is a schematic diagram of an electric energy storage device according to the embodiments of the present application;

[0040] Figure 5 is a primary connection schematic diagram of a point energy storage system on the steam turbine side according to the embodiments of the present application;

[0041] Figure 6 is a structural block diagram of a primary frequency modulation control system according to the embodiments of the present application;

[0042] Figure 7 is a schematic diagram of the internal structure of an electronic device according to the embodiments of the present application. DETAILED DESCRIPTION

[0043] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be described and illustrated below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application. Based on the embodiments provided by the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort belong to the scope of the present application.

[0044] Obviously, the accompanying drawings in the following description are only some examples or embodiments of the present application, and for those of ordinary skill in the art, the present application can also be applied to other similar scenarios without creative effort based on the accompanying drawings. In addition, it can be understood that although the efforts made in the development process can be complex and lengthy, for those of ordinary skill in the art related to the content disclosed in the present application, some design, manufacture or production changes based on the technical content disclosed in the present application are only routine technical means, and should not be understood as insufficient disclosure of the content disclosed in the present application.

[0045] In the present application, "embodiments" means that the specific features, structures or characteristics described in conjunction with the embodiments can be included in at least one embodiment of the present application. The phrase appears at various places in the specification does not necessarily refer to the same embodiment, nor is it mutually exclusive or alternative embodiments. It is explicitly and implicitly understood by those of ordinary skill in the art that the embodiments described in the present application can be combined with other embodiments without conflict.

[0046] Unless otherwise defined, technical terms and scientific terms used in the present application shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. The terms "a", "an", "one", "this", and the like, as used in the present application, do not denote number restriction, but can denote singular or plural. The terms "include", "comprise", "have", and any variations thereof, as used in the present application, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that includes a list of steps or modules (units) is not limited to the listed steps or units, but can further include other steps or units not listed or can further include other steps or units inherent to such process, method, product, or apparatus. The terms "connect", "connected", "couple", and the like, as used in the present application, are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The term "multiple" refers to two or more. The term "and / or" describes the association relationship of the associated objects, which means that there can be three relationships, for example, "A and / or B" can mean that A exists alone, A and B exist together, and B exists alone. The character " / " generally means that the associated objects before and after are in an "or" relationship. The terms "first", "second", "third", and the like, as used in the present application, are merely to distinguish similar objects, and do not represent a specific order for the objects.

[0047] In this paper, it is necessary to understand that the terms involved can be technical means or other summary technical terms for implementing part of the present application. For example, the terms can include:

[0048] Primary frequency regulation: refers to the automatic control process of the control system of the unit in the power grid automatically controlling the increase and decrease of the active power of the unit to limit the change of the frequency of the power grid and maintain the stability of the frequency of the power grid when the frequency of the power grid deviates from the rated value.

[0049] Primary frequency regulation assessment: an evaluation and compensation mechanism developed for the response capability of the primary frequency regulation of the power plant, which can be judged by the following indexes: 15 s output response index, 30 s output response index, and power contribution index.

[0050] According to the "Two Rules" for grid-connected power plants in North China (revised in 2019), the assessment method for primary frequency modulation auxiliary service is as follows: 1) The primary frequency modulation performance assessment of the unit includes 15s output response index assessment, 30s output response index assessment, and power contribution index assessment. Each assessment includes small disturbance assessment and large disturbance assessment, where the maximum frequency deviation of the power grid is less than 0.06 Hz for small disturbance, and the maximum frequency deviation of the power grid is greater than 0.06 Hz for large disturbance; 2) For coal-fired units, gas turbine units, and hydroelectric units, the 15-second output response index is less than 75% for unqualified; 3) For coal-fired units, the 30-second output response index is less than 90% for unqualified; for gas turbine units and hydroelectric units, the 30-second output response index is less than 100% for unqualified; 4) For all coal-fired units, gas turbine units, and hydroelectric units, the power contribution index is less than 75% for unqualified. Other regions also implement similar primary frequency modulation assessment rules.

[0051] 15s output response index: within 15s from the start of the frequency deviation exceeding the dead zone, the percentage of the actual maximum output adjustment of the unit to the theoretical maximum output adjustment, for example, according to the "Two Rules" for grid-connected power plants in North China, the 15s output response index is less than 75% for unqualified.

[0052] 30s output response index: within 30s from the start of the frequency deviation exceeding the dead zone, the percentage of the actual maximum output adjustment of the unit to the theoretical maximum output adjustment, for example, according to the "Two Rules" for grid-connected power plants in North China: for coal-fired units, the 30-second output response index is less than 90% for unqualified; for gas turbine units and hydroelectric units, the 30-second output response index is less than 100% for unqualified;

[0053] Power contribution index: the percentage of the actual contribution of the unit to the theoretical contribution during the frequency modulation duration; for example, according to the "Two Rules" for grid-connected power plants in North China, the power contribution index is less than 75% for unqualified.

[0054] Speed variation ratio: when a steam turbine operates alone, the percentage of the difference between the idle speed and the full load speed to the rated speed is called the speed variation ratio (or non-uniformity, speed variation ratio, etc.) of the regulating system, usually denoted by the symbol δ.

[0055] Gas-steam combined cycle unit: Figure 1 According to the structure diagram of the gas-steam combined cycle unit of the embodiment, as shown in Figure 1 The gas-steam combined cycle unit generally adopts a double-shaft unit, with a gas turbine and a steam turbine each having a generator set, and each having its own control task completed by two sets of control systems.

[0056] The generator set is directly driven by a gas turbine generator, and high-temperature and high-pressure steam is produced in a waste heat boiler using the heat of flue gas to drive a steam turbine generator, thereby forming a gas-steam combined cycle;

[0057] The load adjustment of the gas turbine is mainly realized by changing the fuel supply, and the control loop is composed of multiple control loops selected by a minimum gate. The speed control loop adopts pure proportional control for differential adjustment, and the load control loop adopts PI control for zero-difference adjustment. During primary frequency modulation, the fuel corresponding to the theoretical load change is superimposed or reduced according to the system setting inequality rate to realize the load change of the unit and complete the primary frequency modulation process.

[0058] Coupling characteristics: the coupling characteristics between the gas and the machine in the combined cycle unit; Figure 2 The schematic diagram of the gas-steam combined cycle unit according to the embodiment of the present application is shown in Figure 2 The gas turbine actively responds to the unit load instruction, and the steam turbine passively follows. The load change rate of the combined cycle unit mainly depends on the load change rate of the gas turbine, and the steam heat load of the waste heat boiler changes after the load of the gas turbine changes. There is a large delay in this process, and in most cases, the throttle of the steam turbine remains unchanged, so the load of the steam turbine also changes basically with the steam heat load of the waste heat boiler,

[0059] In summary, there is a complex coupling relationship between the gas turbine and the steam turbine in the combined cycle unit, which leads to the inability to accurately control the output of the gas turbine and the steam turbine, thereby making it difficult to improve the primary frequency modulation performance of the system.

[0060] Currently, most power plants are facing the primary frequency modulation examination of the power grid, and the examination fee is increasing with the increase of the frequency deviation of the power grid. In order to increase economic benefits, the power generation capacity declared to the power grid by the thermal power plant based on the gas-steam combined cycle unit is generally high during the construction period, and there is a problem of insufficient system regulation margin. Therefore, it is impossible to optimize the primary frequency modulation performance of the unit by using the conventional control strategy.

[0061] In order to improve the above-mentioned thermal power plant based on the combined unit, which may not meet the increasingly severe primary frequency modulation examination. The present inventors propose a primary frequency modulation optimization method suitable for the unit of the gas thermal power plant, which adds a same-source frequency modulation device based on a grid-source coordinated controller to the gas turbine system in the combined cycle unit, and configures an energy storage system to the steam turbine. This method not only can correct and compensate the primary frequency modulation load of the gas turbine based on the control strategy of dynamic adjustment of the power change of the power grid; but also can make up for the shortcomings of slow response speed and poor accuracy of the steam turbine. It plays an important role in improving the frequency quality of the power system, relieving the primary frequency modulation pressure of the steam turbine unit, and ensuring the safe and stable operation of the power system.

[0062] Figure 3 is a flow chart of a method for primary frequency modulation control of a thermal power plant according to an embodiment of the present application, as shown in the figure, the flow comprises the following steps: Figure 3

[0063] S201, on the gas turbine side: acquire the grid frequency, perform signal optimization processing on the grid frequency through a same-source frequency modulation device, and perform primary frequency modulation logic operation on the gas turbine using the grid frequency after signal optimization processing to obtain the frequency modulation output instruction of the gas turbine, wherein the same-source frequency modulation device is constructed based on a grid-source coordinated controller;

[0064] The present inventors found in work that in the primary frequency modulation operation logic of a conventional gas turbine, the frequency is represented based on a speed signal (r / min), which has an error with the conventional grid frequency representation, and the error range has exceeded the relevant regulation requirements of primary frequency modulation. Therefore, due to the fact that the gas turbine data and the grid frequency data cannot be kept synchronized, the primary frequency modulation logic operation in this way will inevitably affect the primary frequency modulation effect.

[0065] Further, according to the above “finding”, a same-source frequency modulation device based on a grid-source coordinated controller can be arranged on the gas turbine side to perform signal processing on the grid frequency collected from the external environment, so as to eliminate the error as much as possible and ensure that the signal participating in the logic operation is synchronized with the grid frequency collection data, so as to reduce unnecessary primary frequency modulation examination warnings.

[0066] Specifically, a high-precision frequency transmitter / speed transmitter can be used to process the collected grid frequency signal to obtain data synchronized with the grid frequency for participating in the primary frequency modulation logic operation.

[0067] It should be noted that, for signal reliability, when the frequency signal and the speed signal deviate beyond a certain range, the speed signal should be switched back for primary frequency modulation logic operation.

[0068] Optionally, the proportion of the feedforward action on the gas turbine side can also be increased to improve the response speed of the primary frequency modulation, and a control strategy based on dynamic adjustment of the grid power change can be used to further ensure that the primary frequency modulation action qualified rate meets the grid examination requirements.

[0069] S302, on the steam turbine side: introduce an electric energy storage device to access the steam turbine, and perform primary frequency modulation through the electric energy storage device cooperating with the steam turbine, wherein the frequency modulation output instruction of the electric energy storage device is determined according to the real-time frequency deviation of the grid and the working condition data of the steam turbine.

[0070] ​It is known in the art that, due to the load change of the traditional steam turbine, the steam turbine is passively changed along with the steam heat load of the waste heat boiler, and is usually in a sliding pressure operation state with the throttle valve fully open. Therefore, the steam turbine in the combined cycle unit cannot perform load increase and decrease actions under corresponding frequency fluctuations, and due to the slow response speed of the steam turbine, the steam turbine itself can easily fail the primary frequency regulation of the power grid.

[0071] In the present embodiment, by adding an electric energy storage device to the steam turbine side, the electric energy storage device has the advantages of instantaneous accurate response, strong climbing ability, flexible power output, and strong plasticity. It not only makes up for the shortcomings of slow response speed and poor accuracy of the steam turbine unit, but also improves the frequency quality of the power system and relieves the pressure of primary frequency regulation of the steam turbine unit.

[0072] By using the electric energy storage device to participate in the primary frequency regulation process of the steam turbine, the electric energy storage device assists the steam turbine in primary frequency regulation, realizes decoupling control of the gas turbine and the steam turbine in the combined cycle unit, and by applying an action instruction to the electric energy storage device, the load of the steam turbine can be quickly increased or decreased to quickly respond to the requirements of primary frequency regulation.

[0073] Through the above steps S301 to S302, compared with the traditional primary frequency regulation method used by the gas-steam combined cycle unit, in the present embodiment, by adding a same-source frequency regulation device based on a grid-source coordinated controller to the gas turbine side and configuring an electric energy storage device to the steam turbine side, not only can the control strategy based on the dynamic adjustment of the grid power be used to correct and compensate the primary frequency regulation load of the gas turbine, but also the shortcomings of slow response speed and poor accuracy of the steam turbine unit can be made up. It has important beneficial effects on improving the frequency quality of the power system, relieving the pressure of primary frequency regulation of the steam turbine unit, and ensuring the safe and stable operation of the power system.

[0074] In some embodiments, in order to further improve the primary frequency regulation response speed of the gas turbine, the present embodiment is improved by the following methods:

[0075] By increasing the proportion of the feedforward action of the gas turbine side in the control loop of the combined cycle unit, the primary frequency regulation response speed of the gas turbine is improved;

[0076] At the same time, by configuring a segmented unequal rate and integrating the inertia change of the primary frequency regulation load increment, the problems of not meeting the 15s response index, 30s response index and integral power index in the primary frequency regulation process are solved. The 15s response index and 30s response index reflect the response speed of the primary frequency regulation of the system, and the integral power index reflects the persistence of the primary frequency regulation of the system. The above terms have been described in the aforementioned term introduction, and therefore will not be described in detail here.

[0077] In some embodiments, in order to further ensure the accuracy of primary frequency modulation action, meet the grid primary frequency modulation assessment requirements. In the embodiment of the application, the control method is improved by adopting the mode of dynamically adjusting the control strategy based on the power change of the grid, specifically including:

[0078] First, a specific frequency signal is collected from the PMU unit, and according to the frequency signal, different action amplitudes are configured for different frequency deviation parameters of the power grid;

[0079] The PMU unit is a power management unit, which is a micro-coordination controller for controlling the power function of a digital platform. Further, how to configure the action amplitude is a conventional technical means in the art, and has no effect on the core invention of the application, so it will not be described in detail in this embodiment.

[0080] Second, the frequency deviation parameter configured with the action amplitude is used to participate in the frequency modulation operation to obtain a frequency modulation signal; and the frequency modulation signal is sent to the TCS system and the DEH system to indicate the correct action of the primary frequency modulation and filter noise;

[0081] The TCS system and the DEH system are a gas turbine control system and a digital electro-hydraulic control system, respectively. The TCS system is the core control system of the gas turbine, and the DEH system is the coordination controller under the conditions of starting, stopping, normal operation and accident of the steam turbine.

[0082] In some embodiments, for selecting what kind of electric energy storage device, the embodiment of the application provides the following scheme:

[0083] According to the grid frequency and power-frequency characteristics, the primary frequency modulation demand power is calculated; further, the primary frequency modulation duration is obtained, and according to the primary frequency modulation duration and the primary frequency modulation demand power, the power and capacity of the electric energy storage device to be introduced are determined. Figure 4 is a schematic diagram of an electric energy storage device according to the embodiment of the application.

[0084] Specifically, according to the actual power frequency characteristics of the power grid, it is concluded that a 1MW / 1MWh electric energy storage device needs to be configured. Further, the electric energy storage device can be connected to the 6A section standby 6kV bus interval of the plant power to cooperate with the steam turbine in the combined cycle unit for primary frequency modulation. Figure 5 is a primary connection diagram of a steam turbine side electric energy storage system according to the embodiment of the application.

[0085] In some embodiments, the data transmission between the electric energy storage device and the steam turbine, and the data transmission logic between the steam turbine and the power grid are as follows:

[0086] The working condition data of the steam turbine (generator set output feedback, generator set actual load instruction, generator set primary frequency modulation action flag, generator set output limit, generator set regulation rate limit, etc.) are transmitted from the DCS system to the EMS system through a hard point mode.

[0087] The DCS system is a distributed control system, and the full name in English is Distributed Control System. When a distributed control mode is adopted, the generation unit of each working condition data is connected with the DCS system. Further, the EMS system is an energy management system, which is used for energy scheduling management and real-time data transmission of the electric energy storage device.

[0088] Further, the power grid frequency data is transmitted to the EMS system of the electric energy storage device through a network communication mode, and the EMS system of the electric energy storage device and the coordination controller communicate through a network communication mode.

[0089] In some embodiments, the primary frequency modulation is performed by the electric energy storage device in cooperation with the steam turbine, and the specific implementation process includes:

[0090] The EMS system of the electric energy storage device calculates the frequency modulation output power in real time according to the real-time frequency deviation data of the power grid and the working condition data of the steam turbine, and sends the frequency modulation output power to the coordination controller of the electric energy storage device;

[0091] The coordination controller then performs energy distribution on the total frequency modulation output power, and sends the multiple power control signals obtained by the distribution to each PCS unit of the electric energy storage device to control the output power of each battery cluster.

[0092] In some embodiments, in the process of performing the primary frequency modulation by the electric energy storage device in cooperation with the steam turbine, in order to further ensure the stability of the power grid frequency, the embodiments in the present application also provide the following technical means:

[0093] The real-time frequency on the bus of the electric energy storage device is detected by a frequency detection device, and the active power of the electric energy storage device is dynamically adjusted according to the real-time frequency,

[0094] In the case where the real-time frequency is detected to exceed the dead zone, the coordination controller of the electric energy storage device calculates a compensation value of the active power according to the current working condition and the real-time frequency, and corrects the active power by using the compensation value.

[0095] Then, the control system sends a control instruction to the energy storage system, and after the electric energy storage system outputs, the control system can send a control instruction again in real time according to the energy storage output and the frequency value (this process is a one-second closed-loop control process). Thus, the power grid frequency is adjusted in real time, and the stability of the power grid frequency is improved.

[0096] It is noted that the steps shown in the above flow or the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from here.

[0097] The embodiment also provides a primary frequency modulation control system of a thermal power plant, which is used to implement the above-mentioned embodiment and preferred embodiment, and will not be described again. As used below, the terms "module", "unit", "sub-unit" and the like can be a combination of software and / or hardware that implements a predetermined function. Although the device described in the following embodiment is preferably implemented in software, hardware, or a combination of software and hardware is also possible and contemplated.

[0098] Figure 6 is a structural block diagram of a primary frequency modulation control system according to an embodiment of the present application, as shown in Figure 6 The system comprises a same-source frequency modulation device 60 and an electric energy storage device 61, wherein,

[0099] The same-source frequency modulation device 60 is used to obtain the grid frequency on the gas turbine side and to perform signal optimization processing on the grid frequency. The grid frequency after the signal optimization processing is used to perform a primary frequency modulation logic operation of the gas turbine to obtain a frequency modulation output instruction of the gas turbine. The same-source frequency modulation device 60 is constructed based on a grid-source coordinated controller;

[0100] The electric energy storage device 61 is used to access the steam turbine on the steam turbine side and cooperate with the steam turbine to perform primary frequency modulation. The frequency modulation output instruction of the electric energy storage device 61 is determined according to the real-time frequency offset of the grid and the working condition data of the steam turbine.

[0101] In an embodiment, a computer device can be a terminal. The computer device includes a processor, a memory, a network interface, a display screen and an input device connected through a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operating system and the computer program in the non-volatile storage medium to run. The network interface of the computer device is used to communicate with external terminals through network connection. The computer program is executed by the processor to implement a primary frequency modulation control method of a thermal power plant. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen. The input device of the computer device can be a touch layer overlaid on the display screen, or a key, trackball or touchpad arranged on the shell of the computer device, or an external keyboard, touchpad or mouse, etc.

[0102] In one embodiment, Figure 7 is a schematic diagram of the internal structure of an electronic device according to an embodiment of the present application, as Figure 7 indicated, an electronic device, which can be a server, is provided, and a schematic diagram of the internal structure thereof can be as Figure 7 indicated. The electronic device includes a processor, a network interface, an internal memory, and a non-volatile memory connected through an internal bus, wherein the non-volatile memory stores an operating system, a computer program, and a database. The processor is configured to provide computing and control capabilities, the network interface is configured to communicate with an external terminal through a network connection, the internal memory is configured to provide an environment for the operating system and the computer program to run, the computer program is configured to be executed by the processor to implement a method for primary frequency modulation control of a thermal power plant, and the database is configured to store data.

[0103] Those skilled in the art can understand that Figure 7 the structure shown in the above embodiment is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the electronic device to which the scheme of the present application is applied. Specifically, the electronic device can include more or fewer components than those shown in the diagram, or combine certain components, or have a different arrangement of components.

[0104] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiments can be completed by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer readable storage medium. When the computer program is executed, it can include the processes of the above-mentioned embodiments. Any reference to memory, storage, database, or other medium used in the embodiments provided by the present application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct RAM bus dynamic RAM (DRDRAM), and Rambus dynamic RAM (RDRAM).

[0105] The above embodiments only express several implementation ways of the present application, and the description is specific and detailed, but it should not be understood as a limitation to the patent scope of the application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A primary frequency modulation control method for a thermal power plant, characterized in that: Applied to a gas-steam combined cycle unit, the method comprises: On the gas turbine side: obtaining the grid frequency, performing signal optimization processing on the grid frequency through a homologous frequency modulation device, performing a primary frequency modulation logic operation of the gas turbine using the grid frequency after signal optimization processing, and obtaining a frequency modulation output instruction of the gas turbine, wherein the homologous frequency modulation device is constructed based on a network source coordination controller; On the steam turbine side: an electric energy storage device is introduced and connected to the steam turbine, and the electric energy storage device cooperates with the steam turbine to perform a frequency modulation. The frequency modulation output instruction of the electric energy storage device is determined according to the real-time frequency offset of the power grid and the operating condition data of the steam turbine; On the combustion engine side, the method further includes: Collecting frequency signals from the PMU unit, and configuring different action amplitudes for different frequency deviation parameters of the power grid according to the frequency signals; The frequency deviation parameter of the configured action amplitude is used to participate in the frequency modulation operation to obtain the frequency modulation signal; Send the frequency modulation signal to the TCS system and the DEH system to indicate the correct action of the frequency modulation and the filtering of the clutter; The electric energy storage device cooperates with the steam turbine to perform a frequency modulation, including: The EMS system of the electric energy storage device calculates the frequency-modulated output power in real time based on the real-time frequency deviation data of the power grid and the operating condition data of the steam turbine, and sends the frequency-modulated output power to the coordination controller of the electric energy storage device; The coordination controller distributes the frequency-modulated output power and sends multiple power control signals obtained by the energy distribution to each PCS unit of the electric energy storage device to control the output power of each battery cluster; During the process of performing a frequency modulation by the electric energy storage device in cooperation with the steam turbine, the method further includes: The real-time frequency on the busbar of the electric energy storage device is detected by a frequency detection device, and the active power of the electric energy storage device is dynamically adjusted according to the real-time frequency. Wherein, when it is detected that the real-time frequency exceeds the dead zone, the coordination controller calculates the compensation value of the active power according to the current working condition and the real-time frequency, and uses the compensation value to correct the active power.

2. The method according to claim 1, characterized in that On the combustion engine side, the method further includes: By increasing the feedforward ratio of the gas turbine side in the control loop of the combined cycle unit, the primary frequency regulation response speed of the gas turbine is improved; By configuring the segmented unequal rate and performing integral inertia changes on the primary frequency regulation load increment, the 15s response index, 30s response index, and integral power index during the primary frequency regulation process can be improved.

3. The method according to claim 1, characterized in that Before introducing the electric energy storage device into the steam turbine, the method further includes: Calculate the power required for primary frequency regulation based on the grid frequency and power-frequency characteristics; A primary frequency modulation duration is obtained, and the power and capacity of the electric energy storage device to be introduced are determined according to the primary frequency modulation duration and the primary frequency modulation required power.

4. The method according to claim 1, wherein Data is transmitted between the coordination controller of the electric energy storage device and the EMS system via network communication; The various operating data of the steam turbine are transmitted to its EMS system through hard connection; The EMS system of the electric energy storage device obtains the grid frequency through network communication.

5. A primary frequency modulation control system for a thermal power plant, characterized in that: Used to execute the method according to claim 1, applied to a gas-steam combined cycle unit, the system comprises: a homologous frequency modulation device and an electric energy storage device, wherein: The homologous frequency modulation device is used to obtain the grid frequency on the gas turbine side, perform signal optimization processing on the grid frequency, and use the grid frequency after the signal optimization processing to perform a primary frequency modulation logic operation of the gas turbine to obtain a frequency modulation output instruction of the gas turbine, wherein the homologous frequency modulation device is constructed based on the network source coordination controller; The electric energy storage device is used to be connected to the steam turbine on the steam turbine side and cooperate with the steam turbine to perform a frequency modulation, wherein the frequency modulation output instruction of the electric energy storage device is determined according to the real-time frequency deviation of the power grid and the operating condition data of the steam turbine; On the gas turbine side, frequency signals are collected from the PMU unit, and different action amplitudes are configured for different frequency deviation parameters of the power grid according to the frequency signals; The frequency deviation parameter of the configured action amplitude is used to participate in the frequency modulation operation to obtain the frequency modulation signal; Send the frequency modulation signal to the TCS system and the DEH system to indicate the correct action of the frequency modulation and the filtering of the clutter; The electric energy storage device cooperates with the steam turbine to perform a frequency modulation, including: The EMS system of the electric energy storage device calculates the frequency-modulated output power in real time based on the real-time frequency deviation data of the power grid and the operating condition data of the steam turbine, and sends the frequency-modulated output power to the coordination controller of the electric energy storage device; The coordination controller distributes the frequency-modulated output power and sends multiple power control signals obtained by the energy distribution to each PCS unit of the electric energy storage device to control the output power of each battery cluster; During the process of primary frequency modulation by the electric energy storage device in cooperation with the steam turbine, the frequency detection device detects the real-time frequency on the busbar of the electric energy storage device, and dynamically adjusts the active power of the electric energy storage device according to the real-time frequency. Wherein, when it is detected that the real-time frequency exceeds the dead zone, the coordination controller calculates the compensation value of the active power according to the current working condition and the real-time frequency, and uses the compensation value to correct the active power.

6. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the method according to any one of claims 1 to 4 is implemented.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 4 is implemented.

Images