Self-sustaining control method and system for full-power wind turbine generator

Abstract

The invention discloses a self-sustaining control method and system for a full-power wind turbine generator set, and the method comprises the steps: completing the starting of the wind turbine generator set through the cooperation among a diesel generator, a main control system, a converter and a yaw system of the wind turbine generator set when a power grid is disconnected, supplying power to an auxiliary control system through the power generation of the wind turbine generator set, and quitting the diesel generator. Comprising the following steps: 1) starting a diesel generator and entering a standby state; 2) a standby state; 3) a pre-starting state; 4) a starting state; 5) a converter voltage buildup state; and 6) a self-maintaining state. When the full-power wind turbine generator is disconnected from the power grid, the auxiliary control system can be powered through self power generation, operation of the wind turbine generator is maintained, long-time shutdown of the wind turbine generator is avoided, and maintenance time is shortened. According to the method, extra hardware cost does not need to be increased, and the self-maintaining function can be increased only by carrying out algorithm transformation on an existing system. According to the invention, the fuel filling period of the diesel generator can be greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of full-power wind turbine control, and in particular to a self-sustaining control method, system, storage medium and computing device for a full-power wind turbine. Background Art

[0002] When the wind turbine is disconnected from the power grid, the auxiliary control system needs to be powered by a diesel generator. However, at this time, the wind turbine still has the ability to generate electricity. If the wind turbine generates electricity by itself to supply power to the auxiliary control system, it can reduce the energy consumption of the diesel generator and also maintain the operation of the unit. But currently, in order to maintain the system operation, it is necessary to be powered by a diesel generator, and the long-term disconnection will consume a large amount of energy of the diesel generator, and this problem needs to be solved urgently. Summary of the Invention

[0003] The first object of the present invention is to overcome the disadvantages and deficiencies of the prior art, and provide a reliable self-sustaining control method for a full-power wind turbine, which can greatly reduce the fuel filling cycle of the diesel generator.

[0004] The second object of the present invention is to provide a self-sustaining control system for a full-power wind turbine.

[0005] The third object of the present invention is to provide a storage medium.

[0006] The fourth object of the present invention is to provide a computing device.

[0007] The first object of the present invention is achieved by the following technical solutions: A self-sustaining control method for a full-power wind turbine, which completes the startup of the wind turbine through the cooperation between the diesel generator, the main control system, the converter and the yaw system of the wind turbine when the power grid is disconnected, supplies power to the auxiliary control system by the wind turbine generating electricity by itself and withdraws the diesel generator, and specifically performs the following operations:

[0008] 1) Start the diesel generator and enter the standby state;

[0009] 2) Standby state:

[0010] Detect the state of the high-voltage circuit breaker. If it is in the open state, enter the pre-start state; if it is in the closed state, end; wherein, the high-voltage circuit breaker is used for the connection between the box transformer of the wind turbine and the power grid;

[0011] 3) Pre-start state:

[0012] The main control system delays, waits for each subsystem of the wind turbine to be in a workable state, and then enters the start state;

[0013] 4) Start state:

[0014] The main control system sends the closing commands for the generator-side breaker and the grid-side breaker to the converter. The converter controls the closing of the generator-side breaker and the grid-side breaker. After the closing is completed, the main control system controls the yaw system to face the wind and controls the blade pitch angle to the preset starting position. After that, the wind turbine enters the converter voltage building state;

[0015] 5) Converter voltage building state:

[0016] The converter starts the grid-forming control, and the main control system adjusts the pitch angle to reach the set speed;

[0017] 6) Self-sustaining state:

[0018] The main control system executes the constant speed control. The power supply of the auxiliary control system is automatically switched from the diesel generator to the wind turbine itself, and the diesel generator shuts down and exits.

[0019] Furthermore, in step 1), the auxiliary control power switch KM1 is switched to the position connected to the diesel generator, and the main control system starts the diesel generator. The auxiliary control power switch KM1 is used for the auxiliary control system to connect to the auxiliary control transformer or the diesel generator.

[0020] Furthermore, in step 4), the main control system sends the closing commands for the generator-side breaker and the grid-side breaker to the converter. The converter controls the closing of the generator-side breaker and the grid-side breaker. During this period, the main control system detects the closing signal returned by the converter; after the closing is completed and the main control system receives the closing completion signal, the main control system controls the yaw system to face the wind and controls the blade pitch angle to the starting position β1, where the starting position β1 is set according to the wind turbine parameters of the manufacturer.

[0021] Furthermore, in step 5), after the start-up state of the wind turbine ends, it enters the converter voltage building state. During the voltage building period, the main control system and the converter need to cooperate in timing, as follows:

[0022] 5.1) The main control system sends the operation instruction of the AC voltage source mode to the converter. After receiving the instruction, the machine-side converter performs modulation control to adjust the DC voltage to the set value;

[0023] 5.2) The main control system calculates the torque capacity value based on the wind speed and speed information and sends the torque capacity value to the converter;

[0024] 5.3) The grid-side converter executes the AC voltage source start-up process and receives the torque capacity value to calculate the upper limit of the active power; it establishes the voltage through the grid-forming control and ramps up. After the detected value of the converter grid-side voltage U g reaches the grid-forming voltage set value U gset the grid-side converter sends the AC voltage source status flag bit to the main control system;

[0025] 5.4) While the converter performs step 5.3), the main control system controls the blade pitch angle to change to the target position β2, where β2 is much smaller than β1 and is set according to the wind turbine parameters and site conditions. During the control process, the main control system detects whether the rotational speed reaches the self-sustaining target rotational speed ω ss , if the self-sustaining target rotational speed ω ss is reached and the AC voltage source status flag bit is received, the wind turbine enters the self-sustaining state.

[0026] Further, the step 6) performs the following operations:

[0027] 6.1) The main control system performs constant rotational speed control to issue a pitch control command and maintains the rotational speed at the self-sustaining target rotational speed ω ss , where the input-output power balance is achieved by controlling the pitch angle;

[0028] 6.2) The main control system detects the voltage U as at the low-voltage side of the auxiliary control transformer. When the value of U as reaches the auxiliary control power supply switching set value U asset , the auxiliary control power supply switching switch KM1 is switched from the diesel generator side to the auxiliary control transformer side, and the power supply of the auxiliary control system is switched from the diesel generator to the wind turbine itself, and the diesel generator shuts down and exits.

[0029] The second object of the present invention is achieved by the following technical solution: A self-sustaining control system for a full-power wind turbine, used to implement the self-sustaining control method of the above full-power wind turbine, including:

[0030] A start-up module, used to switch the auxiliary control power supply switching switch KM1 to the position connected to the diesel generator, and the main control system starts the diesel generator;

[0031] A standby state module, used to detect the state of the high-voltage circuit breaker. If it is in the open state, it enters the pre-start state; if it is in the closed state, it ends;

[0032] A pre-start state, used for the main control system to delay, waiting for each subsystem of the wind turbine to be in a workable state, and then entering the start state;

[0033] A start state module, used for the main control system to send closing commands for the machine-side circuit breaker and the grid-side circuit breaker to the converter. The converter controls the machine-side circuit breaker and the grid-side circuit breaker to close. After the closing is completed, the main control system controls the yaw system to face the wind and controls the blade pitch angle to the preset start position. After that, the wind turbine enters the converter voltage build-up state;

[0034] A converter voltage build-up state module, used for the converter to start the grid-forming control, and the main control system adjusts the pitch angle to reach the set rotational speed;

[0035] Self-sustaining state, used for the main control system to perform constant speed control. The power supply of the auxiliary control system is automatically switched from the diesel generator to the wind turbine itself, and the diesel generator shuts down and exits.

[0036] The third object of the present invention is achieved by the following technical solution: A storage medium stores a program, and when the program is executed by a processor, the self-sustaining control method of the full-power wind turbine as described above is realized.

[0037] The fourth object of the present invention is achieved by the following technical solution: A computing device includes a processor and a memory for storing a program executable by the processor. When the processor executes the program stored in the memory, the self-sustaining control method of the full-power wind turbine as described above is realized.

[0038] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0039] 1. The present invention can supply power to the auxiliary control system by its own power generation when the full-power wind turbine is disconnected from the power grid, maintain the operation of the wind turbine, avoid long-term shutdown of the wind turbine, and reduce maintenance time.

[0040] 2. The present invention does not require additional hardware costs. Only by modifying the algorithm of the existing system can the self-sustaining function be added.

[0041] 3. The present invention can significantly reduce the fuel filling cycle of the diesel generator. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a structural block diagram of a full-power wind turbine; in the figure, QF1 is a high-voltage circuit breaker, QF2 is a grid-side circuit breaker of the converter, QF3 is a machine-side circuit breaker of the converter, KM1 is an auxiliary control power supply switching switch, U g is the grid-side voltage of the converter, and U as is the low-voltage side voltage of the auxiliary transformer.

[0043] Figure 2 It is a control logic diagram of the method of the present invention.

[0044] Figure 3 It is a control flow chart of the method of the present invention.

[0045] Figure 4 It is an architecture diagram of the system of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0046] The present invention will be further described in detail below in conjunction with embodiments and the accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0047] Embodiment 1

[0048] See Figures 1 to 3As shown in the figure, this embodiment discloses a self-sustaining control method for a full-power wind turbine. This method completes the startup of the wind turbine through the cooperation between the diesel generator (abbreviated as DG for short), the main control system (abbreviated as MC for short), the converter, and the yaw system when the power grid is disconnected. The wind turbine generates electricity by itself to supply power to the auxiliary control system and the diesel generator is withdrawn. The specific operations are as follows:

[0049] 1) Start the diesel generator and enter the standby state;

[0050] Switch the auxiliary control power switch KM1 to the position connected to the diesel generator. The main control system starts the diesel generator. The auxiliary control power switch KM1 is used for the auxiliary control system to connect to the auxiliary control transformer or the diesel generator. After the diesel generator starts successfully, it enters the standby state.

[0051] 2) Standby state:

[0052] Detect the state of the high-voltage circuit breaker QF1. If it is in the open state, enter the pre-start state; if it is in the closed state, end. The high-voltage circuit breaker QF1 is used for the connection between the box-type transformer of the wind turbine and the power grid.

[0053] 3) Pre-start state:

[0054] The main control system delays for T1 seconds, waiting for each subsystem of the wind turbine to be in a workable state. After each subsystem of the wind turbine is in a workable state, enter the start state. The delay time T1 is determined comprehensively according to the parameters of each device of the wind turbine.

[0055] 4) Start state:

[0056] The main control system sends a closing command for the machine-side circuit breaker QF3 and the grid-side circuit breaker QF2 to the converter. The converter controls the machine-side circuit breaker QF3 and the grid-side circuit breaker QF2 to close. During this period, the main control system detects the closing signal returned by the converter. After the closing is completed and the main control system receives the closing completion signal, the main control system controls the yaw system to face the wind and controls the blade pitch angle to the starting position β1, where the starting position β1 is set according to the wind turbine parameters of the manufacturer. After completion, the wind turbine enters the converter voltage build-up state.

[0057] 5) Converter voltage build-up state:

[0058] After the start state of the wind turbine ends, it enters the converter voltage build-up state. During the voltage build-up period, the main control system and the converter need to cooperate in timing, as follows:

[0059] 5.1) The main control system issues an AC voltage source mode operation instruction to the converter. After the converter receives the instruction, the machine-side converter performs modulation control to adjust the DC voltage to the set value;

[0060] 5.2) The main control system calculates the torque capacity value based on information such as wind speed and rotational speed, and sends this torque capacity value to the converter.

[0061] 5.3) The grid-side converter executes the AC voltage source startup process, and receives the torque capacity value to calculate the upper limit of active power; it establishes the voltage through grid-forming control and ramps up. After the detected value of the converter grid-side voltage U g reaches the grid-forming voltage set value U gset , it sends an AC voltage source status flag bit to the main control system.

[0062] 5.4) While the converter executes step 5.3), the main control system controls the blade pitch angle to change towards the target position β2 (β2 is generally much smaller than β1, and is set according to the wind turbine parameters and on-site conditions). During the control process, the main control system detects whether the rotational speed reaches the self-sustaining target rotational speed ω ss . If it reaches the self-sustaining target rotational speed ω ss and receives the AC voltage source status flag bit, the wind turbine enters the self-sustaining state.

[0063] 6) Self-sustaining state:

[0064] The main control system executes constant rotational speed control, and the power supply of the auxiliary control system is automatically switched from the diesel generator to the wind turbine itself, and the diesel generator shuts down and exits, including the following steps:

[0065] 6.1) The main control system executes constant rotational speed control to issue a pitch command and maintains the rotational speed at the self-sustaining target rotational speed ω ss , where the input-output power balance is achieved by controlling the pitch angle.

[0066] 6.2) The main control system detects the voltage U as on the low-voltage side of the auxiliary control transformer. When the value of U as reaches the auxiliary control power supply switching set value U asset , the auxiliary control power supply switching switch KM1 is switched from the diesel generator side to the auxiliary control transformer side, and the power supply of the auxiliary control system is switched from the diesel generator to the wind turbine itself, and the diesel generator shuts down and exits.

[0067] Embodiment 2

[0068] This embodiment discloses a self-sustaining control system for a full-power wind turbine, used to implement the self-sustaining control method of the full-power wind turbine described in Embodiment 1. As Figure 4 shown, it includes the following functional modules:

[0069] A startup module, used to switch the auxiliary control power supply switching switch KM1 to the position connected to the diesel generator, and the main control system starts the diesel generator.

[0070] Standby state module, used to detect the state of the high-voltage circuit breaker. If it is in the open state, it enters the pre-start state; if it is in the closed state, it ends.

[0071] Pre-start state, used for the main control system to delay. After waiting for each subsystem of the wind turbine to be in a workable state, it enters the start state.

[0072] Start state module, used for the main control system to send closing commands for the machine-side circuit breaker and the grid-side circuit breaker to the converter. The converter controls the machine-side circuit breaker and the grid-side circuit breaker to close. After the closing is completed, the main control system controls the yaw system to face the wind and controls the pitch angle of the blade to a preset start position. After the end, the wind turbine enters the converter voltage build-up state.

[0073] Converter voltage build-up state module, used for the converter to start grid-forming control, and the main control system adjusts the pitch angle to reach the set speed.

[0074] Self-sustaining state, used for the main control system to perform constant-speed control. The power supply of the auxiliary control system is automatically switched from the diesel generator to the wind turbine itself, and the diesel generator shuts down and exits.

[0075] Embodiment 3

[0076] This embodiment discloses a storage medium storing a program, which when executed by a processor, implements the self-sustaining control method of the full-power wind turbine described in Embodiment 1.

[0077] The storage medium in this embodiment can be a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM), a random access memory (RAM), a USB flash drive, a mobile hard disk, or other media.

[0078] Embodiment 4

[0079] This embodiment discloses a computing device, including a processor and a memory for storing the executable program of the processor. When the processor executes the program stored in the memory, it implements the self-sustaining control method of the full-power wind turbine described in Embodiment 1.

[0080] The computing device described in this embodiment can be a desktop computer, a laptop computer, a smart phone, a PDA handheld terminal, a tablet computer, a programmable logic controller (PLC), or other terminal devices with processor functions.

[0081] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement methods and are all included in the protection scope of the present invention.

Claims

1. A self-sustaining control method for a full-power wind turbine, characterized in that This method completes the startup of the wind turbine through the cooperation among the diesel generator, main control system, converter, and yaw system of the wind turbine when the power grid is disconnected. The wind turbine generates electricity by itself to supply power to the auxiliary control system and the diesel generator exits. The specific operations are as follows: 1) Start the diesel generator and enter the standby state; 2) Standby state: Detect the state of the high-voltage circuit breaker. If it is in the open state, enter the pre-start state; if it is in the closed state, end. Among them, the high-voltage circuit breaker is used for the connection between the box transformer of the wind turbine and the power grid; 3) Pre-start state: The main control system delays. After waiting for each subsystem of the wind turbine to be in a workable state, enter the start state; 4) Start state: The main control system sends closing commands for the machine-side circuit breaker and the grid-side circuit breaker to the converter. The converter controls the machine-side circuit breaker and the grid-side circuit breaker to close. After the closing is completed, the main control system controls the yaw system to face the wind and controls the blade pitch angle to the preset start position. After the completion, the wind turbine enters the converter voltage build-up state; 5) Converter voltage build-up state: The converter starts the grid-forming control, and the main control system adjusts the pitch angle to reach the set speed; 6) Self-sustaining state: The main control system performs constant-speed control, and the power supply of the auxiliary control system is automatically switched from the diesel generator to the wind turbine itself, and the diesel generator shuts down and exits.

2. The self-sustaining control method of a full-power wind turbine unit according to claim 1, characterized in that, In step 1), switch the auxiliary control power switch KM1 to the position connecting the diesel generator, and the main control system starts the diesel generator. Among them, the auxiliary control power switch KM1 is used for the auxiliary control system to connect to the auxiliary control transformer or the diesel generator.

3. The self-sustaining control method for a full-power wind turbine unit according to claim 2, wherein In step 4), the main control system sends closing commands for the machine-side circuit breaker and the grid-side circuit breaker to the converter. The converter controls the machine-side circuit breaker and the grid-side circuit breaker to close. During this period, the main control system detects the closing signal returned by the converter; after the closing is completed and the main control system receives the closing completion signal, the main control system controls the yaw system to face the wind and controls the blade pitch angle to the start position β1, where the start position β1 is set according to the wind turbine parameters of the manufacturer.

4. The self-sustaining control method of a full-power wind turbine according to claim 3, characterized in that In step 5), after the start state of the wind turbine ends, enter the converter voltage build-up state. During the voltage build-up period, the main control system and the converter need to cooperate in timing, specifically as follows: 5.1) The main control system sends an instruction to operate in the AC voltage source mode to the converter. After receiving the instruction, the machine-side converter modulates and controls the DC voltage to the set value; 5.2) The main control system calculates the torque capacity value based on the wind speed and speed information and sends the torque capacity value to the converter; 5.3) The grid-side converter executes the AC voltage source startup process and receives the torque capacity value to calculate the upper limit of the active power; Establish voltage and perform ramping through network-forming control. Wait until the detected value of the converter grid-side voltage U g reaches the network-forming voltage set value U gset and then send the AC voltage source status flag bit to the master control system; 5.4) While the converter executes step 5.3), the main control system controls the blade pitch angle to change towards the target position β2, where β2 is much smaller than β1 and is set according to the wind turbine parameters and on-site conditions. During the control process, the main control system detects whether the rotational speed reaches the self-sustaining target rotational speed ω ss , if the self-sustaining target rotational speed ω ss is reached and the AC voltage source status flag bit is received, the wind turbine enters the self-sustaining state.

5. The self-sustaining control method of a full-power wind turbine according to claim 4, characterized in that Step 6) performs the following operations: 6.1) The main control system executes constant speed control to issue a pitch control command and maintains the rotational speed at the self-sustaining target rotational speed ω ss , where the input-output power balance is achieved by controlling the pitch angle; 6.2) The main control system detects the low-voltage side voltage U of the auxiliary control transformer as , when the value of U as reaches the auxiliary control power supply switching set value U asset , then the auxiliary control power supply switching switch KM1 switches from the diesel generator side to the auxiliary control transformer side, the power supply of the auxiliary control system switches from the diesel generator to the wind turbine itself, and the diesel generator shuts down and exits.

6. A self-sustaining control system for a full-power wind turbine, characterized in that It is used to implement the self-sustaining control method of the full-power wind turbine described in any one of claims 1 to 5, including: A startup module, used to switch the auxiliary control power switch KM1 to the position connecting the diesel generator, and the main control system starts the diesel generator; A standby state module, used to detect the state of the high-voltage circuit breaker. If it is in the open state, enter the pre-start state; if it is in the closed state, end; Pre-start state, used for the main control system to delay, waiting for each subsystem of the wind turbine to be in a workable state, and then entering the start state; Start state module, used for the main control system to send closing commands for the machine-side circuit breaker and the grid-side circuit breaker to the converter. The converter controls the closing of the machine-side circuit breaker and the grid-side circuit breaker. After the closing is completed, the main control system controls the yaw system to face the wind and controls the blade pitch angle to a preset start position. After that, the wind turbine enters the converter voltage-building state; Converter voltage-building state module, used for the converter to start grid-forming control, and the main control system adjusts the pitch angle to reach the set speed; Self-sustaining state, used for the main control system to perform constant-speed control, and the power supply of the auxiliary control system is automatically switched from the diesel generator to the wind turbine itself, and the diesel generator shuts down and exits.

7. A storage medium stores a program, characterized in that, When the program is executed by the processor, it implements the self-sustaining control method of the full-power wind turbine described in any one of claims 1 to 5.

8. A computing device, comprising a processor and a memory for storing processor-executable programs, characterized in that, When the processor executes the program stored in the memory, it implements the self-sustaining control method of the full-power wind turbine described in any one of claims 1 to 5.

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