Implementation Method, System, Medium and Equipment for Primary Frequency Regulation of Wind Turbine Generator Set

Abstract

The present invention discloses a method, system, medium and device for realizing primary frequency regulation of a wind turbine generator set. The present invention adopts a constant speed mode. During primary frequency regulation, the speed set value is kept unchanged, and the pitch mechanism action is reduced, fundamentally solving the problem of insufficient response speed caused by too slow pitch control. By quickly adjusting the torque to meet the requirements of the response time, it can quickly respond to the demand of the power grid for primary frequency regulation, playing a key role in the stability of the entire power grid. In short, the present invention can effectively reduce the action of the pitch mechanism, improve the response rate, avoid the long-term operation of the unit in the resonance crossing area, thereby reducing the faults during primary frequency regulation and is worthy of promotion.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power generation, and in particular to a method, system, storage medium and computing device for realizing primary frequency regulation of a wind turbine generator set. Background Art

[0002] With the increasing maturity of wind power generation technology, the grid connection capacity has gradually increased, and the resulting power grid stability problems have become increasingly prominent, which also poses new challenges to the power grid support ability of wind turbine generator sets.

[0003] To ensure the stable operation of the power grid and reduce the impact of wind power access on the power grid frequency quality and stability, wind turbine generator sets are increasingly considered to need to participate in the frequency adjustment of the system. At present, many studies have been carried out on the primary frequency regulation strategy of wind turbine generator sets at home and abroad, and power grid companies have also introduced corresponding standards to restrict various dynamic change processes of wind turbine generator sets when participating in primary frequency regulation. When the power grid frequency rises or falls, the active power of the entire field of wind turbine generator sets needs to be reduced or increased to support the stability of the power grid frequency.

[0004] For the control of wind turbine generator sets, based on the constant power control algorithm, when a power step occurs, the torque control and pitch control act simultaneously to respond to the transient change of the unit. However, although the pitch angle control method can provide a certain amount of power support under the condition of allowable wind speed, there is also the problem of slow response speed, resulting in the unit being unable to respond to the power step within the specified time.

[0005] When the power grid frequency fluctuates, in order to maintain the stability of the power grid, the active power must be quickly changed to support the stability of the power grid. The traditional primary frequency regulation method adopts the constant power mode. When the given power undergoes a step change, both the torque and speed will respond to the change of the active power simultaneously. In the stage below the rated speed, the speed has not reached the rated value and is at the upper boundary of resonance crossing. Both the torque control and pitch control need to act simultaneously to meet the change of power. The torque control is quickly responded by the lower-level converter according to the torque issued value, but the pitch control is borne by the unit itself. Due to the limitation of the pitch motor speed, and when the speed approaches the given value, due to the limitation of the PI adjustment ability itself, the adjustment speed becomes slower and slower, which will inevitably lead to insufficient response speed. Summary of the Invention

[0006] The first object of the present invention is to overcome the deficiencies of the prior art and provide a method for realizing primary frequency regulation of a wind turbine generator set, which can effectively solve the problem that the response speed of the pitch control link is relatively slow during primary frequency regulation, and realize that the wind turbine generator set can quickly and effectively respond to the frequency change of the power grid.

[0007] The second object of the present invention is to provide a system for realizing primary frequency regulation of a wind turbine generator set.

[0008] The third object of the present invention is to provide a storage medium.

[0009] The fourth object of the present invention is to provide a computing device.

[0010] The first object of the present invention is achieved by the following technical solution: A method for realizing primary frequency regulation of a wind turbine generator set, when the wind turbine generator set is in the normal power generation mode, the following steps are executed:

[0011] 1) Obtain the primary frequency regulation flag bit of the unit. If the flag bit is true, execute step 2). If the flag bit is false, exit the primary frequency regulation.

[0012] 2) Obtain the resonance crossing flag bit of the unit. If it is in the resonance crossing interval, exit the primary frequency regulation. If it is not in the resonance crossing interval, execute step 3).

[0013] 3) Obtain the given active power value and the feedback active power value of the unit, calculate the difference ΔPower between the given active power value and the feedback active power value of the unit, and execute step 4).

[0014] 4) Execute the power change rate in the corresponding stage according to the calculated difference ΔPower, and then convert the executed power change rate into the actual power given value Power′ of the unit set , and execute step 5).

[0015] 5) Calculate the torque limit value Torque according to the actual power given value Power′ of the unit set of the unit, and execute step 6).

[0016] 6) Execute the torque PI control of the unit according to the torque limit value Torque, and execute the pitch PI control of the unit according to the given generator speed w set and the feedback generator speed w fbk of the generator.

[0017] Further, in step 3), the calculation formula of the difference ΔPower is as follows:

[0018] ΔPower = Power set - Power fbk

[0019] In the formula, Power set is the given active power value, and Power fbk is the feedback active power value.

[0020] Further, in step 4), according to the calculated difference ΔPower, the power change rate of the corresponding stage is executed, and then the power change rate executed is converted into the actual power set value Power′ of the unit set , specifically as follows:

[0021] When ΔPower ≤ ΔPower1, execute the power change rate Power of the first stage rate1 ;

[0022] When ΔPower1 < ΔPower < ΔPower2, execute the power change rate Power of the second stage rate2 ;

[0023] When ΔPower ≥ ΔPower2, execute the power change rate Power of the third stage rate3 ;

[0024] Among them, ΔPower1 and ΔPower2 are set thresholds, and Power rate1 , Power rate2 , Power rate3 are power change differences;

[0025] The calculation formula of the actual power set value Power′ of the unit set is as follows:

[0026] Power′ set = Power 0 + Power ratei × t

[0027] In the formula, Power 0 is the power value at the initial moment of power change, Power ratei is the power change rate of a certain stage, i = 1, 2, 3; t is the duration from Power 0 to Power′ set .

[0028] Further, in step 5), the calculation formula of the torque limit value Torque is as follows:

[0029] Torque = Power′ set / w

[0030] In the formula, w is the generator speed value calculated according to the following formula when the primary frequency regulation flag changes from false to true. However, when the primary frequency regulation flag is true, the following formula is no longer used to calculate the value of w, but the generator speed value when the primary frequency regulation flag changes from false to true is kept unchanged;

[0031]

[0032]

[0033]

[0034] In the formula, w min is the minimum operating speed of the unit, w max is the maximum operating speed of the unit, k opt is the optimal gain, Power min is the minimum power corresponding to the minimum operating speed of the unit, Power max is the maximum power corresponding to the maximum operating speed of the unit.

[0035] Furthermore, in step 6), the given value w set of the generator speed is calculated as follows:

[0036]

[0037]

[0038]

[0039] In the formula, w min is the minimum operating speed of the unit, w max is the maximum operating speed of the unit, k opt is the optimal gain, Power min is the minimum power corresponding to the minimum operating speed of the unit, Power max is the maximum power corresponding to the maximum operating speed of the unit.

[0040] Furthermore, in step 6), the feedback value w fbk of the generator speed is the actual speed value of the generator detected by the sensor.

[0041] The second object of the present invention is achieved by the following technical solution: A system for realizing primary frequency modulation of a wind turbine generator set is used to realize the method for realizing primary frequency modulation of the above-mentioned wind turbine generator set, and it includes:

[0042] A primary frequency modulation flag bit judgment module, which is used to obtain the primary frequency modulation flag bit of the unit and judge whether the primary frequency modulation flag bit is true or false. If the flag bit is true, the resonance crossing flag bit judgment module is executed. If the flag bit is false, the primary frequency modulation is exited;

[0043] The resonance crossing flag bit judgment module is used to obtain the resonance crossing flag bit of the unit, and judge whether the resonance crossing flag bit is in the resonance crossing interval. If it is in the resonance crossing interval, the primary frequency modulation is exited. If it is not in the resonance crossing interval, the first calculation module is executed;

[0044] The first calculation module is used to obtain the given active power value and the feedback active power value of the unit, and calculate the difference ΔPower between the given active power value and the feedback active power value of the unit;

[0045] The second calculation module executes the power change rate at the corresponding stage according to the difference ΔPower calculated by the first calculation module, and then converts the executed power change rate into the actual power given value Power′ of the unit set ;

[0046] The third calculation module calculates the torque limit value Torque according to the actual power given value Power′ of the unit set ;

[0047] The execution module performs the torque PI control of the unit according to the torque limit value Torque, and performs the pitch PI control of the unit according to the given value w of the generator speed set and the feedback value w of the generator speed fbk ;

[0048] 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 implementation method of primary frequency modulation of the above-mentioned wind turbine generator set is realized.

[0049] 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 implementation method of primary frequency modulation of the above-mentioned wind turbine generator set is realized.

[0050] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0051] The present invention adopts a constant speed mode. During primary frequency modulation, the given value of the speed is kept unchanged, and the action of the pitch mechanism is reduced, fundamentally solving the problem that the response speed is insufficient due to too slow pitch control. By quickly adjusting the torque to meet the requirements of the response time, it can quickly respond to the needs of the power grid for primary frequency modulation, playing a key role in the stability of the entire power grid. In short, the present invention can effectively reduce the action of the pitch mechanism, improve the response rate, avoid the unit running in the resonance crossing area for a long time, thereby reducing the faults during primary frequency modulation, and is worthy of promotion. Description of the Drawings

[0052] Figure 1It is a curve graph of power reference and power feedback.

[0053] Figure 2 It is the architecture diagram of the system of the present invention. Specific embodiments

[0054] 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.

[0055] Embodiment 1

[0056] This embodiment discloses a method for realizing primary frequency regulation of a wind turbine generator set. When the wind turbine generator set is in the normal power generation mode, the following steps are executed:

[0057] 1) Obtain the primary frequency regulation flag bit of the unit. If the flag bit is true, execute step 2). If the flag bit is false, exit the primary frequency regulation.

[0058] 2) Obtain the resonance crossing flag bit of the unit. If it is in the resonance crossing interval, exit the primary frequency regulation. If it is not in the resonance crossing interval, execute step 3).

[0059] 3) Obtain the given active power value Power of the unit set and the feedback active power value Power fbk , as Figure 1 shown, calculate the difference ΔPower between the given active power value Power set and the feedback active power value Power fbk , and execute step 4); wherein, the calculation formula of the difference ΔPower is as follows:

[0060] ΔPower = Power set - Power fbk

[0061] 4) Execute the power change rate of the corresponding stage according to the calculated difference ΔPower, and then convert the executed power change rate into the actual power reference value Power' set of the unit, and execute step 5), specifically as follows:

[0062] When ΔPower ≤ ΔPower1, execute the power change rate Power rate1 of the first stage;

[0063] When ΔPower1 < ΔPower < ΔPower2, execute the power change rate Power rate2 of the second stage;

[0064] When ΔPower ≥ ΔPower2, execute the power change rate Power in the third stage rate3 ;

[0065] where ΔPower1 and ΔPower2 are set thresholds, and Power rate1 , Power rate2 , Power rate3 are power change differences;

[0066] The calculation formula for the actual power setpoint Power′ set of the unit is as follows:

[0067] Power′ set = Power 0 + Power ratei ×t

[0068] In the formula, Power 0 is the power value at the initial moment of power change, Power ratei is the power change rate in a certain stage, i = 1, 2, 3; t is the duration from Power 0 to Power′ set .

[0069] 5) Calculate the torque limit value Torque according to the actual power setpoint Power′ set of the unit, and execute step 6); the calculation formula for the torque limit value Torque is as follows:

[0070] Torque = Power′ set / w

[0071] In the formula, w is the generator speed value calculated according to the following formula when the primary frequency regulation flag changes from false to true. However, when the primary frequency regulation flag is true, the following formula is no longer used to calculate the value of w, but the generator speed value when the primary frequency regulation flag changes from false to true is kept unchanged;

[0072]

[0073]

[0074]

[0075] In the formula, w min is the minimum operating speed of the unit, w max is the maximum operating speed of the unit, k opt is the optimal gain, and Power min is the minimum power corresponding to the minimum operating speed of the unitmax It is the maximum power corresponding to the maximum operating speed of the unit.

[0076] 6) Perform the torque PI control of the unit according to the torque limit value Torque, and perform the pitch PI control of the unit according to the generator speed set value w set and the generator speed feedback value w fbk ; where the generator speed feedback value w fbk is the actual generator speed value detected by the sensor, and the calculation formula of the generator speed set value w set is as follows:

[0077]

[0078]

[0079]

[0080] In the formula, w min is the minimum operating speed of the unit, w max is the maximum operating speed of the unit, k opt is the optimal gain, Power min is the minimum power corresponding to the minimum operating speed of the unit, Power max is the maximum power corresponding to the maximum operating speed of the unit.

[0081] Embodiment 2

[0082] This embodiment discloses a system for realizing primary frequency regulation of a wind turbine generator set, which is used to realize the method for realizing primary frequency regulation of the wind turbine generator set described in Embodiment 1. As Figure 2 shown, the system includes the following functional modules:

[0083] The primary frequency regulation flag bit judgment module is used to obtain the primary frequency regulation flag bit of the unit and judge whether the primary frequency regulation flag bit is true or false. If the flag bit is true, the resonance crossing flag bit judgment module is executed. If the flag bit is false, the primary frequency regulation is exited;

[0084] The resonance crossing flag bit judgment module is used to obtain the resonance crossing flag bit of the unit and judge whether the resonance crossing flag bit is in the resonance crossing interval. If it is in the resonance crossing interval, the primary frequency regulation is exited. If it is not in the resonance crossing interval, the first calculation module is executed;

[0085] The first calculation module is used to obtain the given active power value and the feedback active power value of the unit, and calculate the difference ΔPower between the given active power value and the feedback active power value of the unit;

[0086] The second calculation module executes the power change rate of the corresponding stage according to the difference ΔPower calculated by the first calculation module, and then converts the executed power change rate into the actual power set value Power′ of the unit. set ;

[0087] The third calculation module calculates the torque limit value Torque according to the actual power set value Power′ of the unit. set Calculate the torque limit value Torque;

[0088] The execution module performs the torque PI control of the unit according to the torque limit value Torque, and performs the pitch PI control of the unit according to the generator speed set value w set and the generator speed feedback value w fbk Execute the pitch PI control of the unit.

[0089] Embodiment 3

[0090] This embodiment discloses a storage medium storing a program, which when executed by a processor, implements the method for realizing primary frequency regulation of a wind turbine generator set described in Embodiment 1.

[0091] The storage medium in this embodiment can be a magnetic disk, an optical disc, a computer memory, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a USB flash drive, a mobile hard disk, or other media.

[0092] Embodiment 4

[0093] This embodiment discloses a computing device including a processor and a memory for storing a program executable by the processor. When the processor executes the program stored in the memory, it implements the method for realizing primary frequency regulation of a wind turbine generator set described in Embodiment 1.

[0094] 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, Programmable Logic Controller), or other terminal devices with processor functions.

[0095] 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 method for realizing primary frequency regulation of a wind turbine generator set, characterized in that, when the wind turbine generator set is in the normal power generation mode, the following steps are executed: 1) Obtain the primary frequency regulation flag bit of the unit. If the flag bit is true, execute step 2). If the flag bit is false, exit the primary frequency regulation; 2) Obtain the resonance crossing flag bit of the unit. If it is in the resonance crossing interval, exit the primary frequency regulation. If it is not in the resonance crossing interval, execute step 3); 3) Obtain the given active power value and the feedback active power value of the unit, calculate the difference ΔPower between the given active power value and the feedback active power value of the unit, and execute step 4); 4) Execute the power change rate of the corresponding stage according to the calculated difference ΔPower, and then convert the executed power change rate into the actual power set value Power′ of the unit set , and execute step 5); 5) Given the actual power set value Power′ of the unit set Calculate the torque limit value Torque and execute step 6); 6) Perform the torque PI control of the unit according to the torque limit value Torque, and perform the pitch PI control of the unit according to the generator speed set value w set and the generator speed feedback value w fbk ​ 2. The method for realizing primary frequency regulation of a wind turbine generator set according to claim 1, characterized in that: In step 3), the calculation formula of the difference ΔPower is as follows: ΔPower = Power set - Power fbk where, Power set is the given active power value, and Power fbk is the feedback active power value.

3. The method for realizing primary frequency regulation of a wind turbine generator set according to claim 1, characterized in that: In step 4), according to the calculated difference ΔPower, execute the power change rate of the corresponding stage, and then convert the executed power change rate into the actual power set value Power′ of the unit set , specifically as follows: When ΔPower ≤ ΔPower1, execute the power change rate Power in the first stage rate1 ; When ΔPower1 < ΔPower < ΔPower2, execute the power change rate Power in the second stage rate2 ; When ΔPower ≥ ΔPower2, execute the power change rate Power in the third stage rate3 ; Among them, ΔPower1 and ΔPower2 are set thresholds, and Power rate1 , Power rate2 , Power rate3 are the power change differences; Actual power set value of the unit, Power′ set The calculation formula is as follows: Power′ set = Power 0 + Power ratei × t Wherein, Power 0 is the power value at the initial moment of power change, Power ratei is the power change rate in a certain stage, i = 1, 2, 3; t is from Power 0 to Power′ set duration.

4. The method for realizing primary frequency regulation of a wind turbine generator set according to claim 1, characterized in that: In step 5), the calculation formula of the torque limit value Torque is as follows: Torque=Power′ set / w In the formula, w is the generator speed value calculated according to the following formula when the primary frequency regulation flag bit changes from false to true. However, when the primary frequency regulation flag bit is true, the following formula is no longer used to calculate the value of w, but the generator speed value when the primary frequency regulation flag bit changes from false to true is kept unchanged; where w min is the minimum operating speed of the unit, w max is the maximum operating speed of the unit, k opt is the optimal gain, Power min is the minimum power corresponding to the minimum operating speed of the unit, Power max is the maximum power corresponding to the maximum operating speed of the unit.

5. The method for realizing primary frequency regulation of a wind turbine generator set according to claim 1, characterized in that: In step 6), the given value w of the generator speed set is calculated as follows: where w min is the minimum operating speed of the unit, w max is the maximum operating speed of the unit, k opt is the optimal gain, Power min is the minimum power corresponding to the minimum operating speed of the unit, Power max is the maximum power corresponding to the maximum operating speed of the unit.

6. The method for realizing primary frequency regulation of a wind turbine generator set according to claim 1, characterized in that: In step 6), the generator speed feedback value w fbk is the actual generator speed value detected by the sensor.

7. A system for realizing primary frequency regulation of a wind turbine generator set, characterized in that, used to realize the method for realizing primary frequency regulation of a wind turbine generator set described in any one of claims 1 to 6, and it includes: A primary frequency regulation flag bit judgment module, used to obtain the primary frequency regulation flag bit of the unit and judge whether the primary frequency regulation flag bit is true or false. If the flag bit is true, execute the resonance crossing flag bit judgment module. If the flag bit is false, exit the primary frequency regulation; A resonance crossing flag bit judgment module, used to obtain the resonance crossing flag bit of the unit and judge whether the resonance crossing flag bit is in the resonance crossing interval. If it is in the resonance crossing interval, exit the primary frequency regulation. If it is not in the resonance crossing interval, execute the first calculation module; The first calculation module, used to obtain the given active power value and the feedback active power value of the unit, and calculate the difference ΔPower between the given active power value and the feedback active power value of the unit; The second calculation module executes the power change rate of the corresponding stage according to the difference ΔPower calculated by the first calculation module, and then converts the executed power change rate into the actual power set value Power′ of the unit set ; The third calculation module calculates the torque limit value Torque according to the actual power set value Power′ of the unit set ​ The execution module performs the torque PI control of the unit according to the torque limit value Torque, and performs the pitch PI control of the unit according to the generator speed set value w set and the generator speed feedback value w fbk of the unit.

8. A storage medium storing a program, characterized in that, when the program is executed by a processor, it realizes the method for realizing primary frequency regulation of a wind turbine generator set described in any one of claims 1 to 6.

9. A computing device, including a processor and a memory for storing programs executable by the processor, characterized in that, When the processor executes the program stored in the memory, it implements the method for realizing primary frequency regulation of the wind turbine set according to any one of claims 1 to 6.

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