Bidirectional synchronization method and system suitable for black start of gas turbine

Abstract

The invention relates to the technical field of partial discharge detection of power equipment, in particular to a bidirectional synchronization method and system suitable for black start of a gas turbine. An operator clicks a start button on the DCS, and the synchronizing device receives a command from the DCS and then judges the command; the synchronizing device judges whether the output condition is met or not, if yes, a signal is sent to a diesel generator controller to start a diesel generator, and if not, the synchronizing device does not act; an operator clicks a synchronizing button on the DCS, and a synchronizing device receives a command from the DCS and then judges the command; the synchronizing device judges whether an output condition is met or not, if yes, synchronizing closing is carried out, and if not, no action is carried out; according to the two-way synchronizing system, by flexibly selecting the synchronizing point of the black start system, the time of black start after black start failure is shortened, and equipment damage such as jamming of dynamic and static parts of a gas turbine can be avoided. Reliable operation of auxiliary power in the black start process is guaranteed, safety of a gas turbine unit in the black start process is guaranteed, and the success rate of black start of a gas turbine power plant is increased.

Description

Technical Field

[0001] The invention relates to the technical field of partial discharge detection of electric power equipment, and in particular to a bidirectional synchronization method and system suitable for black start of a gas turbine. Background Art

[0002] During the black start of the gas turbine, the power supply for the plant is initially carried by the diesel generator. After the generator starts to rise from zero voltage, the power supply for the plant needs to be switched to the gas turbine generator to carry the load, so that the gas turbine generator can operate in an isolated grid with the power supply for the plant. After the black start test, the gas turbine shutdown process requires the diesel generator to be connected to the plant power system to ensure the stability of the plant power and security power supply and prevent major equipment damage. During these processes, it is necessary to switch and run the gas turbine starting power supply (diesel generator) and the plant power supply in parallel.

[0003] 1. If the power supply is accidentally black-started during a black start, the black start process may fail at best, and the black start procedure needs to be repeated, which is time-consuming. In severe cases, the engine dynamic and static components may become stuck, making it impossible to restart the engine in a short period of time, and a black start may not be achieved. Summary of the invention

[0004] In view of the above problems existing in the prior art, the present invention is proposed.

[0005] In order to solve the above technical problems, the present invention provides the following technical solution, a two-way synchronization method suitable for black start of a gas turbine, comprising:

[0006] The operator clicks the start button on the DCS, and the synchronization device makes a judgment after receiving the command from the DCS;

[0007] The synchronization device determines whether the output conditions are met. If they are met, it sends a signal to the diesel generator controller to start the diesel generator. If they are not met, it will not act.

[0008] The operator clicks the synchronization button on the DCS, and the synchronization device makes a judgment after receiving the command from the DCS;

[0009] The synchronization device determines whether the output conditions are met. If they are met, the synchronous closing is performed. If not, no action is taken.

[0010] As a preferred solution of a two-way synchronization method suitable for black start of a gas turbine described in the present invention, wherein: the synchronization device makes judgments after receiving a command from a DCS, including: the first diesel generator controller is in an automatic position, the second diesel generator controller is in an automatic position, the diesel generator synchronization device is in an automatic position, the diesel generator synchronization device checks that the 6kVA section incoming line PT is without power, and the diesel generator synchronization device checks that the 6kVA section incoming line switch is in an open state; the synchronization device makes judgments after receiving a command from a DCS, including: the first diesel generator controller is in an automatic position, the second diesel generator controller is in an automatic position, the diesel generator synchronization device is in an automatic position, the diesel generator synchronization device checks that the 6kVA section incoming line PT is powered, and the diesel generator synchronization device checks that the 6kVA section incoming line switch is in a closed state.

[0011] As a preferred scheme of the bidirectional synchronization method suitable for black start of gas turbine described in the present invention, the diesel generator controller starts the diesel generator including automatically starting the unit that reaches the limited load voltage, and the other unit runs in parallel with it.

[0012] As a preferred solution of the two-way synchronization method applicable to the black start of a gas turbine described in the present invention, wherein: the operator clicks the synchronization button on the DCS to include an instruction to restore the power supply of the incoming line switch.

[0013] As a preferred scheme of the bidirectional synchronization method suitable for gas turbine black start described in the present invention, the allowable range of voltage synchronization is low frequency -0.1HZ, overfrequency 0.2HZ, voltage difference ±3V, and angle difference ±8 degrees.

[0014] As a preferred solution of the bidirectional synchronization method suitable for black start of a gas turbine described in the present invention, the synchronization delay is 3S.

[0015] As a preferred scheme of a bidirectional synchronization method suitable for black start of a gas turbine described in the present invention, the synchronization adjustment state includes: detecting synchronization according to the voltage of the medium-voltage bus and the voltage of the incoming line switch, and automatically closing the medium-voltage bus incoming line switch after the synchronization is completed, and the diesel generator set enters the constant power mode; detecting synchronization according to the voltage of the medium-voltage bus and the voltage of the incoming line switch, and automatically closing the diesel generator outlet circuit breaker after the synchronization is completed, and the diesel generator set enters the constant power mode.

[0016] As a preferred solution of the bidirectional synchronization system suitable for black start of a gas turbine described in the present invention, it includes: a collection module, a judgment module, a protection module, and an output module.

[0017] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and is characterized in that when the processor executes the computer program, the steps of any one of the two-way synchronization methods applicable to the black start of a gas turbine are implemented.

[0018] 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 any one of the methods described in a bidirectional synchronization method applicable to a gas turbine black start are implemented.

[0019] Beneficial effects of the present invention: The bidirectional synchronization system can shorten the time for restarting a black start after a black start failure by flexibly selecting the synchronization point of the black start system, and can avoid equipment damage such as jamming of dynamic and static parts of the fuel engine.

[0020] It ensures the reliable operation of the plant power supply during the black start process, ensures the safety of the gas turbine unit during the black start process, and improves the success rate of the black start of the gas turbine power plant. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 A system diagram of a diesel generator assisted gas turbine black start using a two-way synchronization method suitable for a gas turbine black start is provided as an embodiment of the present invention.

[0023] Figure 2 A schematic diagram of the reverse synchronization logic derivation of a bidirectional synchronization method suitable for black start of a gas turbine is provided as an embodiment of the present invention.

[0024] Figure 3 A positive synchronization logic derivation diagram of a two-way synchronization method suitable for black start of a gas turbine is provided as an embodiment of the present invention.

[0025] Figure 4 A system topology diagram of a bidirectional synchronization system suitable for black start of a gas turbine is provided in accordance with an embodiment of the present invention. DETAILED DESCRIPTION

[0026] 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.

[0027] Example 1

[0028] Reference Figure 1-Figure 3 , which is the first embodiment of the present invention, provides a bidirectional synchronization method applicable to a black start of a gas turbine, comprising:

[0029] This two-way synchronization system can shorten the time for restarting the black start after a black start failure by flexibly selecting the synchronization point of the black start system, and can avoid equipment damage such as jamming of the dynamic and static parts of the fuel tank.

[0030] It ensures the reliable operation of the plant power supply during the black start process, ensures the safety of the gas turbine unit during the black start process, and improves the success rate of the black start of the gas turbine power plant.

[0031] Figure 1 This is a typical black start system diagram of a gas turbine power plant, where:

[0032] Medium voltage busbar incoming switch: 61A switch;

[0033] Diesel generator outlet circuit breaker: K11 switch;

[0034] #1 black start diesel generator busbar breaker: K01;

[0035] #2 Black start diesel generator busbar circuit breaker: K02;

[0036] Medium voltage bus: 6kVA section;

[0037] 6kVA section feeder switch: 60A;

[0038] 6kV B section feeder switch: 60B.

[0039] At present, the black start of the 9E unit of Huaneng Nanjing Gas Turbine Power Generation Co., Ltd. uses the auxiliary power provided by the black start diesel generator to start the diesel generator set and realize the parallel operation of multiple diesel generator sets. Close the 6kV plant section diesel generator incoming line switch to restore the 6kV section power supply, close the plant transformer high and low voltage side switches to restore the 380V working section power supply. After the plant power is delivered, start the motors in sequence, including air compressors, gas turbine cranking motors, industrial water pumps, desalted water pumps, high-pressure electric feed water pumps, low-pressure electric feed water pumps, lubricating oil pumps, gas turbine starter motors, cooling water pumps and other auxiliary machines.

[0040] The gas turbine starts in normal start mode and reaches full speed no-load state (FSNL). Once the power plant electrical system is ready, the gas turbine generator breaker (52G) will be closed in the de-energized bus mode. After closing, the diesel generator set and the generator set will operate normally in parallel. After 52G is closed, the gas turbine will switch to frequency control mode. When 52G is closed and the excitation is in full voltage mode, the gas turbine will reach and maintain the minimum load, and the gas turbine speed control will be transferred from the differential control mode to the frequency control mode. The load of the black start diesel generator system will be transferred to the gas turbine generator. After the load transfer is completed, the diesel generator will automatically reduce the load and be de-energized in sequence, and then shut down for cooling. After that, the system closes the line switch 101, and the gas turbine supplies power to the grid.

[0041] During the black start of the gas turbine, the power supply to the plant is initially carried by the diesel generator. After the generator starts to rise from zero, the power supply to the plant needs to be switched to the gas turbine generator to carry the load, so that the gas turbine generator can operate in an isolated grid with the power supply to the plant. After the black start test, the gas turbine shutdown process requires the diesel generator to be connected to the plant power system to ensure the stability of the plant power and security power supply and prevent major equipment damage. During these processes, it is necessary to switch and run the gas turbine starting power supply (diesel generator) and the plant power supply in parallel. By optimizing the diesel generator controller and the synchronization device, according to different synchronization points, the functions of synchronization between plant power and diesel generator and synchronization between diesel generator and plant power can be realized at the same time, as well as the stable load increase and decrease of the diesel generator during the process, to ensure the reliable operation of the plant power during the black start and realize the black start function of the power plant.

[0042] The diesel generator synchronization device enters the synchronization delay of 3s, and then automatically enters the synchronization adjustment state. The synchronization point closes the diesel generator outlet circuit breaker 1 and the diesel generator outlet circuit breaker 2 to maintain constant power mode operation. Figure 3 shown.

[0043] The "anti-synchronization" logic is to use the incoming line switch (61A) of the medium-voltage busbar for factory power as the grid connection point. Before grid connection, the synchronization system will automatically detect the voltage of the medium-voltage busbar (no electricity in the 6kVA section). After the incoming line switch is in the open state, the two diesel generators will start automatically. The unit that reaches the load voltage first will be automatically put into operation, and the other unit will run in parallel with it. According to the delay set by the diesel generator controller, the busbar circuit breaker is controlled to close, and the two feeder switches are closed at the same time. After the diesel generator controller receives the "restore medium-voltage bus power supply" instruction from the gas turbine control system MarkVIe, the controller enters the synchronization delay of 3s and enters the synchronization adjustment state. The synchronization is detected according to the voltage of the medium-voltage busbar and the voltage of the incoming line switch. After the synchronization is completed, the medium-voltage busbar incoming line switch is automatically closed, and the diesel generator set enters the constant power mode. Specific starting conditions are as follows: Figure 2 shown.

[0044] The logic of "positive synchronization" is to use the diesel generator outlet circuit breaker (K11) as the grid connection point. Before grid connection, the diesel generator controller and the synchronization device will automatically detect the voltage of the medium-voltage bus (6kVA section is energized). After the incoming line switch is closed, the two diesel generators will start automatically. The unit that reaches the load voltage first will be automatically put into operation, and the other unit will run in parallel with it. After the diesel generator controller receives the "medium-voltage bus grid connection" instruction from the gas turbine control system MarkVIe, the controller enters a synchronization delay of 3s and enters a synchronization adjustment state. It detects synchronization based on the voltage of the medium-voltage bus and the voltage of the incoming line switch. After the synchronization is completed, the diesel generator outlet circuit breaker will be automatically closed, and the diesel generator set will enter constant power mode. Specific starting conditions are as follows: Figure 3 shown.

[0045] Through the study of the two-way synchronization function, the synchronization of plant power to diesel generator and diesel generator to plant power can be realized, while ensuring the stable load increase and decrease of diesel generators during the process. The two-way synchronization function can ensure the reliable operation of plant power during the black start process, provide protection for the safety of gas turbine units during the black start process, and effectively improve the stability of the black start function of the power plant.

[0046] Example 2

[0047] The second embodiment of the present invention is different from the previous embodiment in that:

[0048] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program codes.

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

[0050] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0051] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of 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, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0052] Example 3

[0053] refer to Figure 4 , which is the third embodiment of the present invention, provides a bidirectional synchronization system suitable for black start of a gas turbine, characterized in that it includes a collection module, a judgment module, a protection module, and an output module.

[0054] The acquisition module is responsible for receiving digital signals and analog signals (in this case, the analog signal is voltage) so that the device can process and control it.

[0055] The signals collected by the acquisition module are:

[0056] Medium voltage bus incoming switch PT three-phase voltage (AC 100V);

[0057] 6kV black start section busbar PT three-phase voltage (AC 100V);

[0058] The opening position status of the medium voltage busbar incoming switch;

[0059] The closing position status of the medium voltage bus incoming switch;

[0060] The closing position status of the diesel generator output circuit breaker;

[0061] The diesel generator outlet circuit breaker open position status;

[0062] The DCS command is "prepare to restore the plant's high-voltage transformer power supply";

[0063] DCS command "restore power supply to the incoming switch";

[0064] The DCS command “Close the switch” is allowed.

[0065] The output module is responsible for converting the digital signal processed inside the device into an analog signal or switch signal that can be received by external devices.

[0066] The signals collected by the output module are:

[0067] The medium-voltage busbar incoming switch for the factory power supply is closed;

[0068] The medium-voltage busbar incoming switch for the factory power supply is open;

[0069] The diesel generator outlet circuit breaker is closed;

[0070] The diesel generator output circuit breaker is open.

[0071] The protection module is responsible for receiving protection instructions, and after receiving the protection instructions, it communicates with the diesel generator controller to emergency stop the diesel generator.

[0072] The signals received by the output module are:

[0073] DCS command: "DCS remote emergency stop command";

[0074] DCS command: "Emergency stop button on the control room console";

[0075] The judgment module performs logical operations based on the collected analog signals and digital signals, and outputs the signals to the output module after obtaining the results. In this case, the judgment module is responsible for judging whether the system can be synchronized.

[0076] Allowable range of synchronous voltage:

[0077] Low frequency -0.1HZ, overfrequency 0.2HZ, voltage difference ±3V, angle difference ±8 degrees.

[0078] Each diesel generator is controlled by an independent diesel generator controller, and the diesel generator controller communicates with the synchronous controller via an RS-485 serial bus. It should be noted that the above embodiments are only used to illustrate the technical solution of the present invention and are not limiting. Although the present invention is described in detail with reference to the preferred embodiments, a person skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A two-way synchronization method suitable for black start of a gas turbine, characterized in that: include, The operator clicks the start button on the DCS, and the synchronization device makes a judgment after receiving the command from the DCS; The synchronization device determines whether the output conditions are met. If they are met, it sends a signal to the diesel generator controller to start the diesel generator. If they are not met, it will not act. The operator clicks the synchronization button on the DCS, and the synchronization device makes a judgment after receiving the command from the DCS; The synchronization device determines whether the output conditions are met. If they are met, the synchronous closing is performed. If not, no action is taken.

2. A two-way synchronization method suitable for black start of a gas turbine as claimed in claim 1, characterized in that: After receiving the command from the DCS, the synchronization device makes judgments including: the first diesel generator controller is in the automatic position, the second diesel generator controller is in the automatic position, the diesel generator synchronization device is in the automatic position, the diesel generator synchronization device checks that the 6kVA section incoming line PT has no power, and the diesel generator synchronization device checks that the 6kVA section incoming line switch is in the open state.

3. A two-way synchronization method suitable for black start of a gas turbine as claimed in claim 2, characterized in that: The diesel generator controller starts the diesel generator, including automatically switching on the unit that has reached the limited load voltage, and running the other unit in parallel with it.

4. A two-way synchronization method suitable for black start of a gas turbine as claimed in claim 3, characterized in that: The operator clicking the synchronization button on the DCS includes an instruction to restore power supply to the incoming line switch.

5. A two-way synchronization method suitable for black start of a gas turbine as claimed in claim 4, characterized in that: The allowable range of voltage synchronization is low frequency -0.1HZ, over frequency 0.2HZ, voltage difference ±3V, and angle difference ±8 degrees.

6. A two-way synchronization method suitable for black start of a gas turbine as claimed in claim 5, characterized in that: The synchronization delay is 3S.

7. A two-way synchronization method suitable for black start of a gas turbine as claimed in claim 6, characterized in that: The synchronization adjustment state includes detecting synchronization based on the busbar PT and the incoming line switch PT. After the synchronization is completed, the incoming line circuit breaker is closed and the unit enters the constant power mode.

8. A system for a two-way synchronization method for a gas turbine black start based on any one of claims 1 to 7, characterized in that: It includes acquisition module, judgment module, protection module and output module.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. 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 method according to any one of claims 1 to 7 are implemented.

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