A high-voltage diesel generator set-assisted 6F gas turbine black start method and system

Abstract

The present invention discloses a high-voltage diesel generator-assisted 6F gas turbine black start method and system, which relates to the technical field of high-voltage gas turbine black start. It includes operating diesel generator sets in parallel to restore in-plant power supply; during the gas turbine startup process, the static frequency converter SFC draws power from the 10kV bus through an isolation transformer and a load switch to provide control of frequency and current and adjust the speed of the gas turbine; the diesel generator sets are paralleled with the gas turbine through reverse synchronization control, and the gas turbine performs black start and enters the island operation mode. The method of the present invention improves the success rate and response speed of the entire black start process through the parallel operation of diesel generator sets; realizes the seamless parallel operation of diesel generator sets and gas turbines through reverse synchronization control, improves the overall reliability and startup success rate of the system, reduces power failures caused by unstable parallel connection, and thus improves the black start efficiency of the entire power system.

Description

Technical Field

[0001] The present invention relates to the technical field of black start of high - pressure gas turbines, and specifically to a method and system for black start of a 6F gas turbine assisted by a high - pressure diesel generator set. Background Art

[0002] With the rapid development of the power system and the continuous increase in the proportion of new energy access, the stability and security of the power grid face huge challenges. Especially in the context of the increasing proportion of large - scale new energy power generation, it is increasingly difficult to ensure the power supply stability of the power grid. In this process, due to the advantages of fast starting speed and high power density, gas turbines have gradually become an important power source for grid black start. However, existing gas turbine black start systems mostly rely on the power provided by a static frequency converter (SFC) to achieve starting. The application of this technology provides relatively stable current and frequency control for gas turbine starting, ensuring that the gas turbine can start smoothly and quickly carry load. At the same time, diesel generator sets, as a stable and reliable emergency power source, provide important guarantees for black start at critical moments of the power grid. Nevertheless, for the black start system of high - pressure gas turbines, there is no relatively mature technical solution that combines the auxiliary starting of diesel generator sets at present. As a result, in extreme cases, the black start time is relatively long and the success rate is low.

[0003] The deficiencies of the current gas turbine black start system are mainly reflected in the following aspects. First, existing gas turbine black start schemes usually only rely on a static frequency converter (SFC) to provide power for the gas turbine, but the starting ability of the SFC is limited. Especially during the starting process of high - pressure and high - power gas turbines, problems such as insufficient starting current or long starting time may occur, leading to black start failure. Second, during the black start process of the gas turbine, there are challenges in the frequency and voltage control of the gas turbine generator island operation. Especially under the condition of a small load in the isolated network, the system frequency fluctuates greatly and it is difficult to achieve stable operation. There is a lack of effective means for coordinated control of frequency and voltage in the existing technology under the isolated operation mode. Third, most of the existing gas turbine black start technologies do not consider the coordinated operation with diesel generator sets, and diesel generator sets can provide important power support as auxiliary starting power sources. However, the anti - synchronization control strategy during their parallel operation is not yet mature, which is likely to cause problems such as voltage and frequency fluctuations and grid instability. In addition, when conducting black start with existing technologies, it is usually impossible to achieve seamless switching of multiple power sources, and the restoration process of in - plant power consumption is easily affected, thereby affecting the entire black start process of the power grid. Summary of the Invention

[0004] In view of the above - mentioned existing problems, the present invention is proposed.

[0005] Therefore, the technical problem to be solved by the present invention is as follows: the existing black start method for gas turbines has insufficient starting current, it is difficult to control the frequency and voltage during island operation, it is impossible to operate in parallel and cooperate with diesel generator sets, and there are also problems of how to achieve seamless switching and stable operation between diesel generator sets and gas turbines.

[0006] To solve the above technical problems, the present invention provides the following technical solution: a high-voltage diesel generator-assisted 6F gas turbine black start method, which includes paralleling diesel generator sets to restore in-plant power supply; during the gas turbine startup process, the static frequency converter SFC draws power from the 10 kV bus through an isolation transformer and a load switch to provide control of frequency and current and adjust the speed of the gas turbine; the diesel generator sets are paralleled with the gas turbine through reverse synchronization control, and the gas turbine performs black start and enters the island operation mode.

[0007] As a preferred embodiment of the high-voltage diesel generator-assisted 6F gas turbine black start method of the present invention, wherein: the paralleling operation includes two 10 kV high-voltage diesel generator sets being connected to the 10 kV diesel generator bus through a first circuit breaker and a second circuit breaker to perform paralleling operation of the diesel generator sets.

[0008] As a preferred embodiment of the high-voltage diesel generator-assisted 6F gas turbine black start method of the present invention, wherein: the power supply restoration includes the diesel generator 10 kV bus being connected to the 10 kV working section II of the in-plant power through a first switch and a second switch to restore the power supply of the bus section, and the diesel generator sets supply power for the restoration of the in-plant power, serving as the power path for the subsequent black start of the gas turbine; the 10 kV working section II and the 10 kV working section I are interconnected through a tie switch to restore the power supply of the 10 kV working section I by the diesel generator sets.

[0009] As a preferred embodiment of the high-voltage diesel generator-assisted 6F gas turbine black start method of the present invention, wherein: the providing of frequency and current control includes that the gas turbine startup depends on the static frequency converter SFC, which draws power from the 10 kV working section I through an isolation transformer and a load switch. The SFC device controls the current and frequency through rectification and inversion, converts 10 kV alternating current into alternating current with a frequency range of 0 - 45 Hz, and controls the startup speed and power factor of the gas turbine; the alternating current output by the SFC supplies power to the stator winding of the gas turbine generator through a disconnector. During the gas turbine startup stage, the SFC is responsible for providing excitation current for the gas turbine stator, and the third switch is in the off state.

[0010] As a preferred embodiment of the black start method for the high-voltage diesel generator-assisted 6F gas turbine according to the present invention, wherein: adjusting the speed of the gas turbine includes that during the start-up process of the gas turbine, the excitation device takes power through the excitation transformer and the load switch, rectifies it, and provides excitation current for the rotor of the gas turbine through the DC switch MGK. Under the control of the SFC, the speed of the gas turbine gradually increases. When it reaches 90% of the rated speed, the SFC gradually withdraws, and the gas turbine maintains the self-sustaining speed by burning natural gas, and the gas turbine generator enters the no-load operation state.

[0011] As a preferred embodiment of the black start method for the high-voltage diesel generator-assisted 6F gas turbine according to the present invention, wherein: paralleling the diesel generator set with the gas turbine includes that after the gas turbine reaches the self-sustaining speed, the diesel generator set and the gas turbine achieve parallel operation through the anti-synchronization function. The system controls the fourth switch to realize anti-synchronization parallel connection between the gas turbine and the diesel generator. The diesel generator set is in the speed regulation mode V-F and operates with the plant service load, adjusting the frequency and voltage of the 10kV bus section.

[0012] As a preferred embodiment of the black start method for the high-voltage diesel generator-assisted 6F gas turbine according to the present invention, wherein: the island operation mode includes that after the gas turbine and the diesel generator are paralleled, the control mode of the diesel generator set is switched from the speed regulation mode V-F to the power mode P-Q, and it operates with an initial load of 3% of the rated power. The gas turbine operates in the island mode with its own plant service power, completes the black start, and the diesel generator set operates in parallel with the gas turbine in the power mode; when the gas turbine stops operating in the island mode, the DCS system issues a tripping command. After the fourth switch trips, the diesel generator set immediately switches back to the speed regulation mode V-F, and the plant service load is taken over by the diesel generator set, and the gas turbine shuts down safely according to the sequence control process.

[0013] Another object of the present invention is to provide a black start system for a high-voltage diesel generator-assisted 6F gas turbine, which can, during the start-up process of the gas turbine, the static frequency converter SFC takes power from the 10kV bus through the isolation transformer and the load switch, provides control of frequency and current, and adjusts the speed of the gas turbine, solving the problem of low stability in the current black start technology for high-voltage gas turbines.

[0014] As a preferred embodiment of the black start system for the high-voltage diesel generator-assisted 6F gas turbine according to the present invention, wherein: it includes a parallel operation module, a black start control module, and an operation switching module; the parallel operation module is used to parallel the diesel generator sets for restoring in-plant power supply; the black start control module is used to, during the start-up process of the gas turbine, the static frequency converter SFC takes power from the 10kV bus through the isolation transformer and the load switch, provides control of frequency and current, and adjusts the speed of the gas turbine; the operation switching module is used to parallel the diesel generator set with the gas turbine through anti-synchronization control, and the gas turbine performs black start and enters the island operation mode.

[0015] A computer device includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the high-voltage diesel generator set assisted 6F gas turbine black start method.

[0016] A computer-readable storage medium stores a computer program thereon. When the computer program is executed by a processor, the steps of the high-voltage diesel generator set assisted 6F gas turbine black start method are implemented.

[0017] Advantages of the present invention: The high-voltage diesel generator set assisted 6F gas turbine black start method provided by the present invention effectively solves the problem of insufficient power supply before the black start of the gas turbine through the parallel operation of the diesel generator set, ensures stable and reliable in-plant power supply before the start of the gas turbine, and improves the success rate and response speed of the entire black start process; through the frequency and current control of the SFC, the smooth acceleration and safe start of the gas turbine are achieved, avoiding the start-up risks brought by current fluctuations or unstable frequencies. This control process improves the start-up efficiency and success rate of the gas turbine, provides important technical support for the self-sustained operation of the gas turbine during the black start process, realizes the seamless parallel operation of the diesel generator set and the gas turbine through anti-synchronization control, ensures that the gas turbine can smoothly enter the island operation mode during the black start process, and the diesel generator set continues to stably output in the power mode, improving the overall reliability and start-up success rate of the system, reducing power failures caused by unstable parallel connection, and thus improving the black start efficiency of the entire power system. The present invention achieves better results in terms of stability, reliability, and efficiency. Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 It is the overall flowchart of a high-voltage diesel generator set assisted 6F gas turbine black start method provided by the first embodiment of the present invention.

[0020] Figure 2 It is the structure diagram of the high-voltage diesel generator set assisted 6F gas turbine black start system provided by the first embodiment of the present invention.

[0021] Figure 3 It is the control system diagram of the black start system of a high-voltage diesel generator set assisted 6F gas turbine black start method provided by the first embodiment of the present invention.

[0022] Figure 4An overall flow chart of a high-pressure diesel-assisted 6F gas turbine black start system provided for the third embodiment of the present invention. DETAILED DESCRIPTION

[0023] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0024] Example 1, reference Figures 1-3 , which is an embodiment of the present invention, provides a black start method for a high-voltage diesel-assisted 6F gas turbine, comprising:

[0025] S1: Run the diesel generator sets in parallel to restore power supply within the factory.

[0026] Furthermore, Figure 2 It is represented as a structural diagram of a high-voltage diesel generator assisted 6F gas turbine black start system. The parallel operation includes two 10kV high-voltage diesel generator sets connected to the 10kV diesel generator bus through the first circuit breaker 9001 and the second circuit breaker 9002 to perform parallel operation of the diesel generator sets.

[0027] It should be noted that power supply restoration includes connecting the 10kV diesel generator bus to the 10kV working section II bus for plant power through the first switch 9004 and the second switch 9006 to restore the power supply of the bus section, and the diesel generator set restores power supply for plant power, which serves as the power supply path for the subsequent black start of the gas turbine; the 10kV working section II and the 10kV working section I are interconnected through the connecting switch 9100, and the diesel generator set restores power supply to the 10kV working section I.

[0028] It should also be noted that the power supply of the 10kV working section II busbar for the factory power supply is quickly restored through the parallel operation of the diesel generator sets, and the power supply of the 10kV working section I busbar is further restored through the interconnecting switch 9100. This process ensures the restoration of basic power supply in the factory and provides the necessary power path for the black start of the gas turbine. This step ensures that the power infrastructure in the factory can regain power supply in a short time during the black start process, preventing the equipment from being unable to operate due to power outages in the entire factory. At the same time, the diesel generator set, as an emergency backup power supply, has high stability and reliability, and can ensure the effectiveness of factory power restoration in extreme environments.

[0029] S2: During the start-up of the gas turbine, the static frequency converter SFC draws power from the 10kV bus through the isolation transformer and load switch, provides frequency and current control, and adjusts the speed of the gas turbine.

[0030] Furthermore, the control of frequency and current includes that the start-up of the gas turbine depends on the static frequency converter (SFC). Power is taken from Section I of the 10 kV operating power grid through an isolating transformer and a load switch 9108. The SFC device controls the current and frequency through rectification and inversion, converts 10 kV alternating current into alternating current with a frequency range of 0 - 45 Hz, and controls the start-up speed and power factor of the gas turbine. The alternating current output by the SFC is supplied to the stator winding of the gas turbine generator through the disconnecting switch 89SS. During the start-up phase of the gas turbine, the SFC is responsible for providing the excitation current for the stator of the gas turbine, and the third switch 52G is in the open state.

[0031] It should be noted that adjusting the speed of the gas turbine includes that during the start-up process of the gas turbine, the excitation device takes power through the excitation transformer and the load switch 9106, rectifies it, and then supplies the excitation current to the rotor of the gas turbine through the DC switch MGK. Under the control of the SFC, the speed of the gas turbine gradually increases. When it reaches 90% of the rated speed, the SFC gradually withdraws, and the gas turbine maintains the self-sustaining speed by burning natural gas. The gas turbine generator enters the no-load operation state.

[0032] It should also be noted that in the initial stage of the gas turbine start-up, the SFC first adjusts the amplitude of the current through precise current control using the rectification module of alternating current to direct current (AC - DC) to ensure stable output power. Subsequently, the inverter module is responsible for converting the direct current back into alternating current with an adjustable frequency of 0 - 45 Hz. The SFC adjusts the output frequency in real time according to the speed feedback signal of the gas turbine, gradually increases the speed of the gas turbine, and prevents excessive current or frequency fluctuations. During the start-up process of the gas turbine, the SFC dynamically adjusts the output power factor to ensure that the system maintains voltage stability at different speeds and avoids system instability caused by power factor mismatch.

[0033] It should also be noted that during the start-up phase of the gas turbine, the SFC supplies power to the stator winding of the gas turbine through the 89SS disconnecting switch. To prevent possible short-circuit situations, the system sets up an electrical interlock mechanism to ensure that the 52G switch remains in the open state during the SFC power supply. Meanwhile, the SFC system is built-in with a short-circuit detection module to monitor the voltage and current values on the output side in real time. If abnormal current fluctuations are detected, the system immediately issues an alarm and triggers the circuit protection to avoid the occurrence of a short circuit. In addition, the isolating transformer plays an electrical isolation role throughout the process, further reducing the short-circuit risk.

[0034] It should also be noted that when the gas turbine starts, the excitation device takes power from the 10 kV working section I, rectifies it and provides excitation current for the gas turbine rotor through the DC switch MGK. During this process, the excitation device dynamically adjusts the magnitude of the excitation current according to the speed sensor signal of the gas turbine and the current feedback of the stator winding. Through the PID control algorithm, the excitation device can ensure that the optimal excitation current is maintained at different speed stages, guaranteeing the smooth acceleration of the gas turbine and the stability of the final speed. In addition, during the startup stage, the excitation device can automatically adapt to different load conditions according to the current reference signal Idref of the SFC and gradually increase the excitation current to avoid current surges.

[0035] It should also be noted that through the frequency and current control of the SFC, the gas turbine can gradually increase its speed during the startup process until it reaches 90% of the rated speed, after which the SFC gradually withdraws and the gas turbine enters the self-sustaining speed stage. At the same time, the SFC provides excitation current for the gas turbine stator to ensure the stability of the current during the startup process of the gas turbine and prevent startup failures caused by unstable current. The function of this step is to provide precise current and frequency control required for the startup of the gas turbine, enabling its speed to gradually increase according to the predetermined control strategy while ensuring the safety and stability of the electrical system. The role of the SFC is not only to provide power, but also to ensure that the gas turbine can accelerate stably at each stage and finally reach the normal operating state by adjusting the frequency and current magnitude.

[0036] S3: The diesel generator set is paralleled with the gas turbine through anti-synchronizing control, and the gas turbine performs a black start and enters the island operation mode.

[0037] Furthermore, paralleling the diesel generator set with the gas turbine includes that after the gas turbine reaches the self-sustaining speed, the diesel generator set and the gas turbine achieve parallel operation through the anti-synchronizing function. The system controls the fourth switch 9101 to realize the anti-synchronizing parallel connection between the gas turbine and the diesel generator. The diesel generator set is in the speed regulation mode V-F and operates with the plant service load, adjusting the frequency and voltage of the 10 kV bus section.

[0038] It should be noted that the island operation mode includes that after the gas turbine and the diesel generator are paralleled, the control mode of the diesel generator set switches from the speed regulation mode V-F to the power mode P-Q and maintains an initial load operation of 3% of the rated power. The gas turbine operates in the island mode with its own plant service power to complete the black start. Figure 3 It shows the control system diagram of the black start system. The diesel generator set operates in parallel with the gas turbine in the power mode. When the gas turbine stops operating in the island mode, the DCS system issues a trip command. After the fourth switch 9101 trips, the diesel generator set immediately switches back to the speed regulation mode V-F, and the plant service load is taken over by the diesel generator set. The gas turbine shuts down safely according to the sequence control process.

[0039] It should also be noted that after the gas turbine reaches 90% of its rated speed and the SFC trips, the gas turbine will automatically switch to burning natural gas to maintain self-sustained operation. At this time, the fuel supply system of the gas turbine adjusts the supply of natural gas in real time through the controller to ensure that the gas turbine can maintain a stable speed without the help of the SFC. During the process of the speed gradually stabilizing, the gas turbine control system will gradually transition the load from the static state to the dynamic state to ensure that the speed and power output of the gas turbine remain stable under different load conditions. The gas turbine controller automatically adjusts the fuel injection rate through the speed and power feedback signals to prevent the gas turbine speed from fluctuating too much when the load increases.

[0040] It should also be noted that when the gas turbine is operating in parallel with the diesel generator set, the diesel generator set will switch from the speed regulation mode (V-F) to the power mode (P-Q) when the system meets specific voltage and frequency conditions. Specifically, when the system detects that the voltage fluctuation of the gas turbine generator is within the range of ±1% and the frequency fluctuation is within ±0.1 Hz, the diesel generator control system will automatically switch to the power mode. In this mode, the diesel generator set will undertake a fixed power output (3% of the rated power) to evenly share the plant electricity load. During the entire load transfer process, the diesel generator and the gas turbine controller monitor the bus voltage and frequency in real time to ensure the stability of the system during load transfer and avoid electrical system disturbances caused by excessive voltage or frequency fluctuations.

[0041] It should also be noted that through anti-synchronization control, seamless parallel operation of the diesel generator set and the gas turbine has been successfully achieved, enabling the gas turbine to enter the island operation mode. During the parallel operation process, the diesel generator set switches from the speed regulation mode (V-F) to the power mode (P-Q) and maintains the initial load operation, ensuring the power stability of the gas turbine in island operation. Anti-synchronization control ensures that after the gas turbine reaches the self-sustained speed, the diesel generator set can be seamlessly paralleled with it, avoiding voltage fluctuations and frequency instability problems that may occur in traditional parallel control. The realization of this function not only ensures the grid stability in the island mode but also provides a solid foundation for the subsequent recovery of the grid.

[0042] Embodiment 2 is an embodiment of the present invention, which provides a method for black start of a high-voltage diesel generator-assisted 6F gas turbine. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0043] First, in this embodiment, an experiment was conducted to simulate the black start process of a high - voltage diesel - generator set assisting a 6F gas turbine to verify its stability and feasibility in extreme environments. First, two 10kV high - voltage diesel - generator sets (#1 and #2) were introduced into the experimental power grid and operated in parallel. The two diesel - generator sets were connected to the 10kV diesel - generator bus through circuit breakers 9001 and 9002 for paralleling operation to ensure power supply restoration. Through switches 9004 and 9006, the diesel - generator bus delivered electrical energy to the 10kV working section II of the plant service power, forming a preliminary path for power supply restoration. At the same time, the experimental design considered the power supply demand in extreme cases. The 10kV working section II and the 10kV working section I were interconnected through tie switch 9100, ensuring the breadth and stability of power supply restoration and providing reliable power support for the subsequent black start of the gas turbine.

[0044] During the start - up process of the gas turbine, the static frequency converter (SFC) draws power from the 10kV bus through an isolation transformer and load switch 9108, providing accurate frequency and current control. The SFC rectifies 10kV alternating current into direct current and then inverses it into adjustable alternating current of 0 - 45Hz, achieving precise control of the gas turbine speed. Different speed stages were set in the experiment, and by real - time monitoring the current and frequency output by the SFC, it was ensured that there were no current surges and electrical fluctuations during the gas turbine start - up process. When reaching 90% of the rated speed, the SFC gradually withdrew from operation, and the gas turbine maintained its speed by burning natural gas and finally entered the no - load operation state.

[0045] After the gas turbine started up and reached a stable speed, the diesel - generator set and the gas turbine were operated in parallel through anti - synchronization control. Under anti - synchronization control, switch 9101 achieved seamless paralleling of the two power sources, ensuring the stability of frequency and voltage during the switching process. At this time, the operation mode of the diesel - generator set switched from the speed - regulation mode (V - F) to the power mode (P - Q), and the initial power was set to 3% of the rated power to ensure power supply stability during the gas turbine island operation. The experiment also simulated the stop operation of the gas turbine island mode through the DCS system. After receiving the stop signal, the diesel - generator set automatically switched back to the speed - regulation mode (V - F) to ensure seamless takeover of the plant service power load.

[0046] Example 3, referring to Figure 4 , is an embodiment of the present invention, providing a high - voltage diesel - generator - assisted 6F gas - turbine black - start system, including a paralleling operation module, a black - start control module, and an operation switching module.

[0047] The parallel operation module is used to operate the diesel generator sets in parallel to restore the in-plant power supply; the black start control module is used to obtain power from the 10 kV bus through the static frequency converter (SFC) via the isolation transformer and load switch during the start-up process of the gas turbine, provide the control of frequency and current, and adjust the speed of the gas turbine; the operation switching module is used to parallel the diesel generator sets with the gas turbine through anti-synchronization control, and the gas turbine performs black start and enters the island operation mode.

[0048] If a function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present invention. The foregoing storage medium includes: USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs, etc., which can store program codes.

[0049] The logic and / or steps represented in the flowchart or described in other ways herein, for example, can be considered as a definite sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or in combination with these instruction execution systems, apparatuses, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.

[0050] More specific examples (nonexhaustive list) of computer-readable media include the following: electrical connection parts with one or more wirings (electronic devices), portable computer disk cartridges (magnetic devices), random access memories (RAMs), read-only memories (ROMs), erasable programmable read-only memories (EPROMs or flash memories), fiber optic devices, and portable compact disc read-only memories (CDROMs). Additionally, a computer-readable medium can even be paper or other suitable media on which a program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpretation, or, if necessary, other suitable processing, and then stored in a computer memory.

[0051] It should be understood that each part of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, any one or a combination of the following technologies well known in the art can be used: discrete logic circuits having logic gate circuits for implementing logic functions on data signals, application specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc. It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

[0052] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A black start method for a high-voltage diesel-assisted 6F gas turbine, characterized in that: include: Put the diesel generator sets into parallel operation to restore power supply within the factory; The parallel operation includes two 10kV high-voltage diesel generator sets connected to a 10kV diesel generator busbar via a first circuit breaker (9001) and a second circuit breaker (9002) to perform parallel operation of the diesel generator sets; During the gas turbine startup process, the static frequency converter SFC draws power from the 10kV bus through the isolation transformer and load switch to provide frequency and current control and adjust the speed of the gas turbine; The control of providing frequency and current includes that the gas turbine starts up by relying on a static frequency converter SFC, which takes power from the 10kV working section I through an isolation transformer and a load switch (9108), and the SFC device controls the current and frequency through rectification and inversion, converts the 10kV AC into AC with a frequency range of 0-45Hz, and controls the starting speed and power factor of the gas turbine; The SFC outputs alternating current to supply power to the stator winding of the gas turbine generator through the isolating switch (89SS). During the start-up phase of the gas turbine, the SFC is responsible for providing excitation current to the gas turbine stator, and the third switch (52G) is in the disconnected state; The diesel generator set is connected in parallel with the gas turbine through anti-synchronous control, and the gas turbine is black-started and enters the island operation mode.

2. The black start method of a high-voltage diesel-assisted 6F combustion engine according to claim 1, characterized in that: The power supply restoration includes connecting the diesel generator 10kV busbar to the 10kV working section II busbar for the plant power supply through the first switch (9004) and the second switch (9006), restoring the power supply of the busbar section, and the diesel generator set restoring the power supply for the plant power supply as the power supply path for the subsequent black start of the gas turbine; The 10kV working section II is interconnected with the 10kV working section I through a contact switch (9100) to restore the power supply of the diesel generator set to the 10kV working section I.

3. The black start method of a high-voltage diesel-assisted 6F combustion engine as claimed in claim 2, characterized in that: The adjustment of the speed of the gas turbine includes that during the start-up process of the gas turbine, the excitation device obtains power through the excitation transformer and the load switch (9106), and after rectification, the excitation current is provided to the gas turbine rotor through the DC switch MGK. Under the control of the SFC, the speed of the gas turbine is gradually increased. When it reaches 90% of the rated speed, the SFC is gradually withdrawn, the gas turbine maintains a self-sustaining speed by burning natural gas, and the gas turbine generator enters a no-load operation state.

4. The black start method of a high-voltage diesel-assisted 6F combustion engine as claimed in claim 3, characterized in that: The method of connecting the diesel generator set and the gas turbine in parallel includes that after the gas turbine reaches a self-sustaining speed, the diesel generator set and the gas turbine are connected in parallel through the anti-synchronous function. The system controls the fourth switch (9101) to connect the gas turbine and the diesel generator in anti-synchronous parallel. The diesel generator set is in the speed regulation mode VF, operates with the factory power load, and adjusts the frequency and voltage of the 10kV bus section.

5. The black start method of a high-voltage diesel-assisted 6F combustion engine as claimed in claim 4, characterized in that: The island operation mode includes that after the gas turbine is connected in parallel with the diesel generator, the diesel generator unit control mode is switched from the speed control mode VF to the power mode PQ, and the initial load of 3% of the rated power is maintained, the gas turbine operates in the island mode with its own factory power, the black start is completed, and the diesel generator unit operates in parallel with the gas turbine in the power mode; When the gas turbine island stops running, the DCS system issues a trip command. After the fourth switch (9101) is tripped, the diesel generator unit immediately switches back to the speed-reducing mode VF, the plant power load is taken over by the diesel generator unit, and the gas turbine is safely shut down according to the sequential control process.

6. A system using the black start method of a 6F gas turbine assisted by a high-voltage diesel generator as claimed in any one of claims 1 to 5, characterized in that: Including parallel operation module, black start control module, operation switching module; The parallel operation module is used to parallel operate the diesel generator sets to restore power supply within the factory; The black start control module is used to control the frequency and current and adjust the speed of the gas turbine during the startup of the gas turbine. The static frequency converter SFC takes power from the 10kV bus through the isolation transformer and the load switch. The operation switching module is used to connect the diesel generator set in parallel with the gas turbine through anti-synchronous control, and the gas turbine performs a black start and enters an island operation mode.

7. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, the steps of the black start method of a high-voltage diesel-assisted 6F gas engine according to any one of claims 1 to 5 are implemented.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the black start method of a high-voltage diesel-assisted 6F combustion engine according to any one of claims 1 to 5 are implemented.

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