Primary frequency regulation coordinated control method and device based on double-fed variable pumped storage unit

Abstract

The present disclosure provides a primary frequency modulation coordinated control method and device based on a double-fed variable pumped storage unit, which belongs to the field of pumped storage technology. Among them, the method includes real-time acquisition of the operating parameters of the double-fed variable pumped storage unit and the grid frequency of the power grid system; generating a primary frequency modulation power according to the grid frequency; generating a power setting value according to the primary frequency modulation power and the allocated power; generating a primary frequency modulation speed according to the primary frequency modulation power, the power setting value and the actual power value; adjusting the guide vane opening according to the power setting value and the actual power value, and adjusting the speed of the pump turbine according to the allocated power, the primary frequency modulation speed and the actual speed of the pump turbine. In the present disclosure, when the primary frequency modulation occurs, the speed change of the pump turbine is used to release or absorb the rotational inertia to instantly change its power, and at the same time, the guide vane change of the pump turbine coordinates to respond to the primary frequency modulation load demand, so that the precise control of the primary frequency modulation can be achieved quickly and accurately.

Description

Technical Field

[0001] The present invention belongs to the technical field of pumped storage, and in particular relates to a coordinated control method and device based on primary frequency regulation of a double-fed variable pumped storage unit. Background Art

[0002] As an efficient and clean power source, pumped storage units have the characteristics of flexible start and stop and fast response. Pumped storage units play a very important role in promoting the large-scale development and utilization of new energy, enhancing the reliable supply capacity of the power system and ensuring the safety and stability of the power system. At the same time, they can also optimize the power structure, achieve green environmental protection, achieve overall energy conservation and consumption reduction of the power system, and improve the overall economic benefits.

[0003] Traditional fixed-speed pumped storage units use synchronous motors, and the unit speed is the same as the grid frequency, so the unit can only run at a constant speed at the synchronous speed. At this time, the fixed-speed unit cannot adapt to large head fluctuations, and the excessive water hammer effect in the hydraulic system can easily cause ultra-low frequency oscillation of the grid frequency. Since the power regulation of the fixed-speed unit is a mechanical process, the regulation speed is slow, and the regulation effect is poor for wind power output with strong randomness and volatility.

[0004] The new variable speed pumped storage unit has achieved the decoupling of the unit speed and system frequency, and has shown better regulation performance than the traditional fixed speed pumped storage unit in the frequency and power regulation process of the power grid. The variable speed pumped storage unit adopts a doubly fed motor or a full power converter, and has the characteristics of variable speed constant frequency operation, which can broaden the operating range of the pump turbine and realize the rapid regulation of active power.

[0005] Compared with traditional fixed-speed pumped-storage units, the advantages and application value of variable-speed pumped-storage units are that they have the ability to operate at variable speed and constant frequency and to quickly adjust active and reactive power; improve the operating status of the unit, improve operating efficiency and adaptability to water head; enhance the transient stability of the power system, and smooth out system frequency oscillations caused by fluctuations in new energy output.

[0006] At present, although a number of variable speed pumped storage units have been built in some areas, the application of doubly fed variable speed pumped storage units is still in its infancy. Summary of the invention

[0007] The present invention aims to solve at least one of the technical problems existing in the prior art and provide a device that can release or absorb the rotational inertia of a pump-turbine by changing the rotational speed of the pump-turbine while adjusting the guide vane opening of the guide vane pump-turbine, so as to achieve the purpose of quickly adjusting the power generation of the unit and thus promptly responding to a primary frequency regulation demand.

[0008] In order to achieve the above objectives, in a first aspect, an embodiment of the present disclosure provides a primary frequency regulation coordinated control method based on a double-fed variable pumped storage unit, the method comprising:

[0009] Collecting the operating parameters of the double-fed variable pumped storage unit and the grid frequency of the grid system in real time, wherein the operating parameters include the actual power value and the actual speed value of the pump turbine;

[0010] For each collected operation parameter and grid frequency, the following operations are performed:

[0011] If the grid frequency exceeds the set dead zone, generating a frequency modulation power according to the grid frequency;

[0012] generating a power setting value according to the primary frequency regulation power and the allocated power allocated by the automatic power generation control system;

[0013] generating a primary frequency modulation speed according to the primary frequency modulation power, the power setting value and the actual power value;

[0014] The guide vane opening of the pump-turbine is adjusted by a first feedback controller according to the power setting value and the actual power value, and the speed of the pump-turbine is adjusted by a second feedback controller according to the allocated power allocated by the automatic power generation control system, the primary frequency modulation speed and the actual speed of the pump-turbine.

[0015] In some embodiments, generating a primary frequency modulation speed according to the primary frequency modulation power, the power setting value and the actual power value includes:

[0016] Determine whether the absolute value of the primary frequency modulation power is greater than 0, obtain a first determination result, and generate a first pulse signal according to the first determination result;

[0017] Determine whether the difference between the power setting value and the actual power value is within a first set value range, obtain a second determination result, and generate a second pulse signal according to the second determination result;

[0018] Inputting the first pulse signal into the S terminal of the first trigger, and inputting the second pulse signal into the R terminal of the first trigger, to obtain a first signal output by the first trigger;

[0019] Input the second pulse signal to the S terminal of the second flip-flop, input the first pulse signal to the R terminal of the second flip-flop, and obtain a second signal output by the second flip-flop;

[0020] Obtaining a speed change value and a rate setting value according to the first signal and the second signal;

[0021] The primary frequency modulation speed is obtained according to the speed change value and the rate setting value.

[0022] In some embodiments, obtaining a rotation speed change value according to the first signal and the second signal includes:

[0023] Input the first signal as the first control signal of the first selector into the first selector, and input the primary frequency modulation power at the current moment and the first output signal of the first selector at the current moment into the first selector respectively, so that the first selector selects one of the primary frequency modulation power at the current moment and the first output signal at the current moment as the latest first output signal to be output;

[0024] Calculate the product of the latest first output signal and a set negative constant to obtain a first intermediate value;

[0025] The second signal is input into the second selector as a second control signal of the second selector, and the first intermediate value and 0 are input into the second selector, so that the second selector selects one of the first intermediate value and 0 as the rotation speed change value to be output.

[0026] In some embodiments, obtaining a rate change value according to the first signal and the second signal includes:

[0027] Input the first signal as the first control signal of the first selector into the first selector, and input the primary frequency modulation power at the current moment and the first output signal of the first selector at the current moment into the first selector respectively, so that the first selector selects one of the primary frequency modulation power at the current moment and the first output signal at the current moment as the latest first output signal to be output;

[0028] Calculate the product of the absolute value of the latest first output signal and a set positive constant to obtain a second intermediate value;

[0029] The second signal is input into the third selector as the third control signal of the third selector, and the second intermediate value and the second preset value are input into the third selector, so that the third selector selects one of the second intermediate value and the second preset value as the rate change value to output.

[0030] In some embodiments, adjusting the guide vane opening of the pump turbine according to the power setting value and the actual power value by the first feedback controller includes:

[0031] Calculating a difference between the power setting value and the actual power value to obtain a first difference;

[0032] The guide vane opening of the pump turbine is adjusted according to the first difference by the first feedback controller.

[0033] In some embodiments, the AC excitation control system is controlled by a second feedback controller to adjust the speed of the pump-turbine according to the allocated power allocated by the automatic power generation control system, the primary frequency modulation speed, and the actual speed of the pump-turbine, including:

[0034] determining a distribution speed according to the distribution power distributed by the automatic power generation control system;

[0035] Calculating the sum of the distribution speed and the primary frequency modulation speed to obtain a speed setting value;

[0036] Calculating a difference between the speed setting value and the actual speed to obtain a second difference;

[0037] The second feedback controller controls the AC excitation control system to adjust the rotation speed of the pump turbine according to the second difference.

[0038] In a second aspect, the present disclosure further provides a primary frequency regulation coordinated control device based on a double-fed variable pumped storage unit, the device comprising:

[0039] A collection module is configured to collect the operating parameters of the double-fed variable pumped storage unit and the grid frequency of the power grid system in real time, wherein the operating parameters include the actual power value and the actual speed value of the pump turbine;

[0040] A first calculation module is configured to generate a primary frequency modulation power according to the grid frequency when the grid frequency exceeds a set dead zone;

[0041] A second calculation module is configured to generate a power setting value according to the primary frequency regulation power and the allocated power allocated by the automatic power generation control system;

[0042] A third calculation module is configured to generate a primary frequency modulation speed according to the primary frequency modulation power, the power setting value and the actual power value;

[0043] The control module is configured to adjust the guide vane opening of the pump-turbine according to the power setting value and the actual power value through a first feedback controller, and at the same time control the AC excitation control system to adjust the speed of the pump-turbine according to the allocated power allocated by the automatic power generation control system, the primary frequency regulation speed and the actual speed of the pump-turbine through a second feedback controller.

[0044] In some embodiments, the third calculation module includes:

[0045] A first judgment module is configured to judge whether the absolute value of the primary frequency modulation power is greater than 0, obtain a first judgment result, and generate a first pulse signal according to the first judgment result;

[0046] a second judgment module, configured to judge whether the difference between the power setting value and the actual power value is within a set value range, obtain a second judgment result, and generate a second pulse signal according to the second judgment result;

[0047] A first trigger, comprising a first S terminal and a first R terminal, configured to generate a first signal according to the first pulse signal inputted from the first S terminal and the second pulse signal inputted from the first R terminal;

[0048] A second trigger, comprising a second S terminal and a second R terminal, configured to generate a second signal according to the second pulse signal inputted by the second S terminal and the first pulse signal inputted by the second R terminal;

[0049] A first calculation submodule is configured to obtain a rotation speed change value and a rate setting value according to the first signal and the second signal;

[0050] The second calculation submodule is configured to obtain the primary frequency modulation speed according to the speed change value and the rate setting value.

[0051] In some embodiments, the first computing submodule includes:

[0052] A first selector is configured to select one of the primary frequency modulation power at a current moment and the first output signal of the first selector at a current moment as the latest first output signal to be output according to the first signal;

[0053] A first calculation unit is configured to calculate the product of the latest first output signal and a set negative constant to obtain a first intermediate value;

[0054] The second selector is configured to select one of the first intermediate value and 0 as a rotation speed change value to output according to the second signal.

[0055] In some embodiments, the first computing submodule further includes:

[0056] A second calculation unit is configured to calculate the product of the absolute value of the latest first output signal and a set positive constant to obtain a second intermediate value;

[0057] The third selector is configured to select one of the second intermediate value and the second preset value as a rate change value to output according to the second signal.

[0058] In a third aspect, the present disclosure further provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the computing method of the first aspect described above is implemented.

[0059] In a fourth aspect, the present disclosure further provides a computer-readable storage medium storing a computer program for executing the computing method of the first aspect.

[0060] In a fifth aspect, the present disclosure further provides a computer program product, including a computer program / instruction, which implements the steps of the computing method of the first aspect when the computer program / instruction is executed by a processor.

[0061] In the disclosed embodiment, when primary frequency modulation occurs, the speed change of the pump-turbine is simultaneously utilized to release or absorb the rotational inertia to instantaneously change the power of the pump-turbine. Combined with the change in the guide vanes of the pump-turbine, a coordinated response to the primary frequency modulation load demand is achieved, thereby achieving precise control of the primary frequency modulation quickly and accurately. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, 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 disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0063] Figure 1 A flow chart of a coordinated control method for primary frequency regulation based on a double-fed variable pumped storage unit provided in an embodiment of the present disclosure;

[0064] Figure 2 A schematic diagram of a primary frequency regulation coordinated control method for a double-fed variable pumped storage unit provided in an embodiment of the present disclosure;

[0065] Figure 3 A schematic diagram of generating a frequency modulation speed provided by an embodiment of the present disclosure;

[0066] Figure 4 A structural block diagram of a primary frequency regulation coordinated control device based on a double-fed variable pumped storage unit provided in an embodiment of the present disclosure;

[0067] Figure 5 A structural block diagram of a third computing module provided in an embodiment of the present disclosure;

[0068] Figure 6 A structural block diagram of a first computing submodule provided in an embodiment of the present disclosure;

[0069] Figure 7A schematic diagram of the physical structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0070] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail and completely in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present disclosure.

[0071] At present, the application of double-fed variable-speed pumped storage units is not yet mature, and most are still in the laboratory simulation stage. For the control of primary frequency regulation of pumped storage units under power generation conditions, a single turbine guide vane opening or speed response primary frequency regulation is mainly used, resulting in slow primary frequency regulation response and poor effect under the power generation conditions of double-fed variable-speed pumped storage units.

[0072] Based on the above problems existing in the prior art, in a first aspect, an embodiment of the present disclosure provides a primary frequency regulation coordinated control method based on a double-fed variable pumped storage unit.

[0073] Figure 1 A flow chart of a coordinated control method for primary frequency regulation based on a double-fed variable pumped storage unit provided in an embodiment of the present disclosure. Figure 2 A schematic diagram of a primary frequency regulation coordinated control method for a double-fed variable pumped storage unit provided in an embodiment of the present disclosure. The double-fed variable pumped storage unit may include a first feedback controller, a second feedback controller, an AC excitation control system connected to the second feedback controller, and a pump-turbine connected to the first feedback controller, and the AC excitation control system is connected to the pump-turbine, wherein the first feedback controller and the second feedback controller may be the same feedback controller. Figure 1-Figure 2 As shown, the method specifically comprises the following steps:

[0074] S1. Real-time collection of operating parameters of the double-fed variable pumped storage unit and the grid frequency of the power grid system, wherein the operating parameters include the actual power value and the actual speed value of the pump turbine.

[0075] For each collected operation parameter and grid frequency, the following steps S2 to S5 are performed:

[0076] S2. When the grid frequency exceeds a set dead zone, a frequency modulation power is generated according to the grid frequency.

[0077] S3. Generate a power setting value according to the primary frequency modulation power and the allocated power allocated by the automatic power generation control system.

[0078] S4. Generate a primary frequency modulation speed according to the primary frequency modulation power, the power setting value and the actual power value.

[0079] S5. The guide vane opening of the pump-turbine is adjusted according to the power setting value and the actual power value by the first feedback controller. Meanwhile, the AC excitation control system is controlled to adjust the speed of the pump-turbine according to the allocated power allocated by the automatic power generation control system, the primary frequency modulation speed and the actual speed of the pump-turbine by the second feedback controller.

[0080] Specifically, Figure 2 As shown, when the double-fed variable pumped storage unit monitors that the grid frequency f exceeds the set dead zone, that is, when a primary frequency modulation occurs, a primary frequency modulation power P2 is generated according to the slip function, and the final power setting value Pref is determined together with the allocated power P1 allocated by the automatic generation control system (abbreviated as: AGC). The power setting value Pref is compared with the actual power value P, and the guide vane opening of the guide vane water pump turbine is adjusted through the first feedback controller according to the comparison result.

[0081] When a frequency modulation occurs, if the actual power value P of the pump-turbine is changed solely by controlling the guide vanes, the power response rate will be slow due to the mechanical characteristics of the guide vanes. In addition, the water hammer effect when the guide vanes are changed will also affect the frequency modulation effect. The speed of the double-fed variable pumped storage unit is controlled by the AC excitation system, and the response time is extremely fast.

[0082] The present disclosure can confirm the difference between the current required power value and the actual power value P based on the primary frequency modulation power P2, the power setting value Pref and the actual power value P, and then change the power by changing the rotation speed according to the difference.

[0083] In the disclosed embodiment, when primary frequency modulation occurs, the power is instantly changed by simultaneously utilizing the change in rotational speed to release or absorb rotational inertia, thereby achieving the purpose of rapidly adjusting the generating power of the unit and thus promptly responding to the primary frequency modulation demand. Combined with the change in guide vanes to coordinately respond to the primary frequency modulation load demand, precise control of the primary frequency modulation can be achieved quickly and accurately.

[0084] In some embodiments, the step S5 of adjusting the guide vane opening of the pump turbine according to the power setting value and the actual power value by the first feedback controller specifically includes the following steps:

[0085] S51. Calculate the difference between the power setting value and the actual power value to obtain a first difference.

[0086] S52. Regulating the guide vane opening of the pump-turbine according to the first difference through the first feedback controller.

[0087] Specifically, Figure 2 As shown, the power setting value is the power currently required by the pump-turbine. By calculating the difference between the power setting value Pref and the actual power value P, the direction and scale of the power adjustment of the pump-turbine can be accurately determined. The direction of adjustment refers to whether to increase or decrease the power of the pump-turbine, and the scale refers to the specific size of the power adjustment of the pump-turbine.

[0088] In some embodiments, in step S5, the second feedback controller controls the AC excitation control system to adjust the speed of the pump-turbine according to the allocated power allocated by the automatic power generation control system, the primary frequency modulation speed, and the actual speed of the pump-turbine, specifically including the following steps:

[0089] S53, determining a distribution speed according to the distribution power distributed by the automatic power generation control system.

[0090] S54, calculating the sum of the distribution speed and the primary frequency modulation speed to obtain a speed setting value.

[0091] S55. Calculate the difference between the speed setting value and the actual speed to obtain a second difference.

[0092] S56. Control the AC excitation control system to adjust the rotation speed of the pump-turbine according to the second difference through the second feedback controller.

[0093] Specifically, Figure 2 As shown, according to the allocated power P1 allocated by the automatic power generation control system, the allocated speed n allocated by the automatic power generation control system is determined based on the coordination curve. The speed setting value N refers to the speed required by the pump turbine.

[0094] The disclosed embodiment can accurately adjust the rotation speed of the pump turbine according to the rotation speed setting value N and the actual rotation speed.

[0095] It is understandable that the present disclosure can change the power instantly by adjusting the speed of the pump-turbine and changing the way of releasing or absorbing the rotational inertia. That is, in step S5, the adjustment of the guide vane opening of the pump-turbine and the adjustment of the speed of the pump-turbine are both to change the power of the pump-turbine, and the two are coordinated to jointly respond to the primary frequency modulation demand. Among them, the actual power value P and the actual speed of the pump-turbine are collected in real time. With the adjustment of the guide vane opening of the pump-turbine and the adjustment of the speed of the pump-turbine, the actual power value P and the actual speed of the pump-turbine are also constantly changing. Finally, the actual power value P of the pump-turbine is getting closer and closer to the power setting value Pref, and the precise control of the primary frequency modulation can be achieved quickly and accurately.

[0096] refer to Figure 2, when the primary frequency regulation does not occur in the doubly fed variable pumped storage unit under power generation conditions, the primary frequency regulation power P2=0, the primary frequency regulation speed n1=0, the speed setting value N=n (distributed speed), and the power setting value Pref=P1 (distributed power). When the primary frequency regulation occurs, P2≠0, that is, P2 can be greater than 0 or less than 0. When P2 is greater than 0, it means that the power required by the pump turbine is greater than the current actual power value P, and the current actual power value P needs to be increased; conversely, when P2 is less than 0, it means that the power required by the pump turbine is less than the current actual power value P, and the current actual power value P needs to be reduced. When a primary frequency modulation occurs, if the actual power value P of the pump-turbine is changed by controlling the guide vanes alone, the power response rate will be slow due to the mechanical characteristics of the guide vanes. In addition, the water hammer effect when the guide vanes of the pump-turbine are changed will also affect the frequency modulation effect. The speed of the double-fed variable pumped storage unit is controlled by the AC excitation system, and the response time is extremely fast. Therefore, when a primary frequency modulation occurs, the speed change of the pump-turbine is used to release or absorb the rotational inertia to instantly change the power. In addition, the change of the guide vanes of the pump-turbine coordinates the response to the primary frequency modulation load demand, so that precise control of the primary frequency modulation can be achieved quickly and accurately.

[0097] The following specifically introduces the control strategy of the primary frequency regulation speed n1 of the double-fed variable pumped storage unit when designing the primary frequency regulation provided by the embodiment of the present disclosure.

[0098] In power generation conditions, when the speed of the pump-turbine decreases, the rotational inertia is released, and this part of the inertia will be converted into active power to generate electricity for the grid; when the speed of the pump-turbine increases, the rotational inertia is absorbed, thereby reducing the power generation of the unit. The formula is

[0099] (1)

[0100] Wherein, W1 and W2 are the angular velocities of the pump-turbine before and after the speed change, in rad / s; T is the angular velocity change time, in s; △P is the power change during the speed change of the pump-turbine, in w; J is the moment of inertia constant, in kgm 2 .

[0101] According to the above formula (1), the faster the speed of the pump turbine, the greater the active power released or absorbed. Based on this, when the primary frequency modulation occurs, the change rate of the primary frequency modulation speed n1 is faster before the primary frequency modulation begins. With the adjustment of the power and speed of the pump turbine, the primary frequency modulation speed n1 gradually decreases. When the load of the double-fed variable pumped storage unit approaches the required frequency modulation load, the primary frequency modulation speed n1 slowly returns to 0.

[0102] Figure 3A schematic diagram of generating a frequency modulation speed is provided in an embodiment of the present disclosure.

[0103] like Figure 3 As shown, in some embodiments, step S4, generating a primary frequency modulation speed according to the primary frequency modulation power, the power setting value and the actual power value, specifically includes the following steps:

[0104] S41, judging whether the absolute value of the primary frequency modulation power is greater than 0, obtaining a first judgment result, and generating a first pulse signal according to the first judgment result. Figure 3 As shown, it is determined whether a frequency modulation is triggered. When the absolute value of the frequency modulation power P2 is greater than 0, it indicates that a frequency modulation is triggered. When the absolute value of the frequency modulation power P2 is equal to 0, it indicates that a frequency modulation is not triggered.

[0105] S42, judging whether the difference between the power setting value and the actual power value is within a first set value range, obtaining a second judgment result, and generating a second pulse signal according to the second judgment result.

[0106] The first set value range can be used to identify the accuracy of a frequency modulation. Figure 3 As shown, when the difference between the power setting value Pref and the actual power value P is within the first set numerical range, a frequency modulation operation is completed, and no further frequency modulation operation is required. Conversely, when the difference between the power setting value Pref and the actual power value P is not within the first set numerical range, a frequency modulation operation needs to be continued until the difference between the power setting value Pref and the actual power value P is within the first set numerical range, and a frequency modulation operation is completed. Optionally, the set numerical range can be [-0.001, 0.001], and other ranges can also be set according to actual needs, and the present disclosure does not limit this.

[0107] S43. Input the first pulse signal into the S terminal of the first trigger, and input the second pulse signal into the R terminal of the first trigger to obtain a first signal output by the first trigger.

[0108] The first pulse signal and the second pulse signal are opposite pulse signals, the first trigger may be an SR trigger (set-reset trigger), and the first signal output by the first trigger is generally 0 or 1. The first signal identifies whether a frequency modulation operation is performed.

[0109] S44. Input the second pulse signal into the S terminal of the second trigger, input the first pulse signal into the R terminal of the second trigger, and obtain a second signal output by the second trigger.

[0110] The first pulse signal and the second pulse signal are opposite pulse signals, the second trigger can also be an SR trigger (set-reset trigger), and the second signal output by the second trigger is generally 1 or 0. The second signal indicates whether a frequency modulation operation is completed. That is, the second signal is generally an opposite signal to the first signal.

[0111] S45. Obtain a rotation speed change value and a rate setting value according to the first signal and the second signal.

[0112] The first signal indicates whether a frequency modulation operation is performed, and the second signal indicates whether a frequency modulation operation is completed. The embodiment of the present disclosure determines the speed change value and the rate setting value for speed adjustment according to the first signal and the second signal, so as to better adjust the speed.

[0113] S46, according to the speed change value and the rate setting value, obtain the primary frequency modulation speed. Figure 3 As shown, the speed change value and the rate setting value V pass through the rate module to finally generate a frequency modulation speed n1.

[0114] Of course, the present disclosure can also use other methods to generate a frequency modulation speed n1, for example, only perform the judgment of step S41, input the judgment result of step S41 into the S end of the first trigger and the R end of the second trigger respectively, and input the opposite number of the judgment result of step S41 into the R end of the first trigger and the S end of the second trigger respectively; or only perform the judgment of S42, and perform similar processing on the judgment result of S42 as the judgment result of step S41 above, which will not be repeated here. Alternatively, the trigger can be replaced with other methods to output the first signal and the second signal, and the present disclosure does not limit this.

[0115] The embodiment of the present disclosure uses a first trigger to output a first signal and a second trigger to output a second signal, which can lock the primary frequency modulation power P2 at the time when the primary frequency modulation occurs, making the primary frequency modulation speed control provided by the present disclosure more accurate.

[0116] Continue to refer Figure 3 In some embodiments, step S45, obtaining a speed change value according to the first signal and the second signal, specifically comprises the following steps:

[0117] S451. Input the first signal into the first selector as the first control signal of the first selector, and input the primary frequency modulation power at the current moment and the first output signal of the first selector at the current moment into the first selector respectively, so that the first selector selects one of the primary frequency modulation power at the current moment and the first output signal at the current moment as the latest first output signal output.

[0118] That is, if Figure 3 As shown, when the first signal is 0, it means that the primary frequency modulation is not triggered at present, and the primary frequency modulation power P2 at the current moment is selected as the first output signal output. At this time, the primary frequency modulation power P2 is 0; when the first signal is 1, it means that the primary frequency modulation is triggered, and the first output signal of the first selector at the current moment is selected as the latest first output signal output, that is, the primary frequency modulation power P2 at the moment when the primary frequency modulation occurs is selected as the first output signal output, so as to adjust the speed according to the primary frequency modulation power P2 at the moment when the primary frequency modulation occurs.

[0119] S452: Calculate the product of the latest first output signal and a set negative constant to obtain a first intermediate value.

[0120] like Figure 3 As shown, the negative constant m can be set in advance according to the power generation condition of the double-fed variable pumped storage unit. When the primary frequency modulation occurs, the size of the first intermediate value △n is proportional to the size of the primary frequency modulation power P2, but in the opposite direction. That is, when the primary frequency modulation power P2 is a positive number, the first intermediate value △n should be adjusted in the direction of reducing the power of the pump turbine, and when the primary frequency modulation power P2 is a negative number, the first intermediate value △n should be adjusted in the direction of increasing the power of the pump turbine.

[0121] S453, input the second signal as the second control signal of the second selector into the second selector, and input the first intermediate value and 0 into the second selector, so that the second selector selects one of the first intermediate value and 0 as the speed change value to be output.

[0122] That is, if Figure 3 As shown, when the second signal is 1, it means that the current actual power value P meets the power setting value Pref, and 0 is selected as the speed change value output, that is, there is no need to adjust the speed; when the second signal is 0, it means that the current actual power value P does not meet the power setting value Pref, and the first intermediate value △n is selected as the speed change value output to adjust the speed according to the primary frequency modulation power P2 at the moment when the primary frequency modulation occurs.

[0123] In some embodiments, step S45, obtaining a rate change value according to the first signal and the second signal, specifically comprises the following steps:

[0124] S451. Input the first signal as the first control signal of the first selector into the first selector, and input the primary frequency modulation power at the current moment and the first output signal of the first selector at the current moment into the first selector respectively, so that the first selector selects one of the primary frequency modulation power at the current moment and the first output signal at the current moment as the latest first output signal output.

[0125] S455, calculate the product of the absolute value of the latest first output signal and a set positive constant c to obtain a second intermediate value. Figure 3 As shown, the set positive constant c can be a constant set in advance according to the power generation condition of the double-fed variable pumped storage unit. The second intermediate value V1 is proportional to the absolute value of the primary frequency modulation power P2.

[0126] S456. Input the second signal into the third selector as the third control signal of the third selector, and input the second intermediate value and the second preset value into the third selector, so that the third selector selects one of the second intermediate value and the second preset value as the rate change value output.

[0127] Among them, Figure 3 As shown, the second preset value V2 is a positive number with a smaller value. Optionally, the second intermediate value is generally set to 7 to 8 times the second preset value.

[0128] That is, when the second signal is 0, it means that the current actual power value P does not meet the power setting value Pref, and the third selector outputs the second intermediate value V1 as the rate change value to generate the rate setting value according to the primary frequency modulation power P2; when the second signal is 1, it means that the current actual power value P meets the power setting value Pref, and the third selector outputs the second preset value V2 with a smaller value as the rate change value, in order to reduce the primary frequency modulation speed n1 to 0 at a slower rate range.

[0129] It is understandable that the above steps S451 to S453 and steps S451 to S456 can be executed simultaneously.

[0130] by Figure 3 Take the example to explain the primary frequency modulation speed control logic as a whole.

[0131] When the primary frequency modulation occurs, the absolute value of the primary frequency modulation power P2 is greater than 0, the S end of the SR1 trigger is 1, the R end is 0, the SR1 trigger output is 1, and the output of the selection 1 module is the P2 value when the primary frequency modulation occurs. P2 is multiplied by m to obtain the speed setting value △n. When P2 is a positive number, △n is a negative number. Since ABS (Pref-P) is greater than 0.001 at this time, the output of the selection 2 module is △n, and △n is assigned to n1 through the rate module. When ABS (Pref-P) is greater than 0.001, the rate setting value V is equal to V1, and V1 is proportional to the absolute value of P2. When ABS (Pref-P) is less than or equal to 0.001, it indicates that the primary frequency modulation load response meets the requirements, so the selection 2 module output is 0, and the rate setting value V=V2. V2 is a smaller positive number, the purpose is to make n1 reach 0 at a slower rate range.

[0132] The disclosed embodiment adopts the logic of the primary frequency modulation speed control and designs that when the primary frequency modulation occurs, the rate of change of n1 is fast in the early stage, and when the unit load approaches the required frequency modulation load, n1 slowly returns to 0.

[0133] Combination Figure 2 and Figure 3 , taking the primary frequency modulation power P2 as a positive number as an example, when the primary frequency modulation occurs, P2 is greater than 0, P1 is unchanged, Pref is greater than P, and the guide vane of the pump turbine starts to act through the PI controller to change the active power; on the other hand, because P1 is unchanged, n is unchanged, and n1 is Figure 3 Logically, as the speed of V1 decreases from 0 to △n, the speed setting value N also decreases accordingly. Since the excitation system that controls the speed is a fast control system, the actual speed of the unit also quickly changes to the set value. During the process of reducing the actual speed of the unit, the rotational inertia is released and converted into active power, which can quickly release active power. Under the common action of the speed and guide vanes of the pump-turbine, the active power P is equal to Pref. At this time, n1 reaches 0 at the rate range of V2, and the unit speed needs to be restored to the rate before frequency modulation. Since V2 is relatively small, the active power absorbed in this process is small, and power stability can be achieved through the closed-loop control of the guide vanes of the pump-turbine.

[0134] The primary frequency regulation control method for the double-fed variable-speed pumped storage unit in the power generation condition proposed in the present invention assists in releasing or absorbing active power by designing the speed change of the pump-turbine, and realizes the purpose of quickly responding to the frequency regulation load by jointly controlling the guide vanes of the pump-turbine. It is of great significance to the stable frequency control in the power generation condition and the safe operation of the unit.

[0135] On the second aspect, based on the same inventive concept, the disclosed embodiment also provides a primary frequency regulation coordinated control device based on a double-fed variable pumped storage unit.

[0136] Figure 4 The structure block diagram of a primary frequency regulation coordinated control device 40 based on a double-fed variable pumped storage unit provided in an embodiment of the present disclosure. Figure 4 As shown, the collaborative control device 40 includes a collection module 41 , a first calculation module 42 , a second calculation module 43 , a third calculation module and a control module 45 .

[0137] The acquisition module 41 is configured to acquire the operating parameters of the double-fed variable pumped storage unit and the grid frequency of the grid system in real time, wherein the operating parameters include the actual power value and the actual speed value of the pump turbine.

[0138] The first calculation module 42 is configured to generate a primary frequency modulation power according to the grid frequency when the grid frequency exceeds a set dead zone.

[0139] The second calculation module 43 is configured to generate a power setting value according to the primary frequency regulation power and the allocated power allocated by the automatic power generation control system.

[0140] The third calculation module 44 is configured to generate a primary frequency modulation rotation speed according to the primary frequency modulation power, the power setting value and the actual power value.

[0141] The control module 45 is configured to adjust the guide vane opening of the pump-turbine according to the power setting value and the actual power value through a first feedback controller, and at the same time control the AC excitation control system to adjust the speed of the pump-turbine according to the allocated power allocated by the automatic power generation control system, the primary frequency regulation speed and the actual speed of the pump-turbine through a second feedback controller.

[0142] Figure 5 A structural block diagram of a third computing module provided in an embodiment of the present disclosure.

[0143] like Figure 5 As shown, in some embodiments, the third calculation module 44 includes a first judgment module 441 , a second judgment module 442 , a first trigger 443 , a second trigger 444 , a first calculation submodule 445 and a second calculation submodule 446 .

[0144] The first judgment module 441 is configured to judge whether the absolute value of the primary frequency modulation power is greater than 0, obtain a first judgment result, and generate a first pulse signal according to the first judgment result.

[0145] The second judgment module 442 is configured to judge whether the difference between the power setting value and the actual power value is within a set value range, obtain a second judgment result, and generate a second pulse signal according to the second judgment result.

[0146] The first trigger 443 includes a first S terminal and a first R terminal, and is configured to generate a first signal according to the first pulse signal input to the first S terminal and the second pulse signal input to the first R terminal.

[0147] The second trigger 444 includes a second S terminal and a second R terminal, and is configured to generate a second signal according to the second pulse signal input to the second S terminal and the first pulse signal input to the second R terminal.

[0148] The first calculation submodule 445 is configured to obtain a rotation speed change value and a speed setting value according to the first signal and the second signal.

[0149] The second calculation submodule 446 is configured to obtain the primary frequency modulation speed according to the speed change value and the rate setting value.

[0150] Figure 6 A structural block diagram of a first computing submodule provided in an embodiment of the present disclosure.

[0151] like Figure 6 As shown, in some embodiments, the first calculation submodule 445 includes a first selector 51 , a first calculation unit 52 , a second selector 53 , a second calculation unit 54 and a third selector 55 .

[0152] The first selector 51 is configured to select one of the primary frequency modulation power at the current moment and the first output signal of the first selector at the current moment as the latest first output signal to be output according to the first signal.

[0153] The first calculation unit 52 is configured to calculate the product of the latest first output signal and a set negative constant to obtain a first intermediate value.

[0154] The second selector 53 is configured to select one of the first intermediate value and 0 as the rotation speed change value to be output according to the second signal.

[0155] like Figure 6 As shown, in some embodiments, the first calculation submodule 445 includes not only a first selector 51 , a first calculation unit 52 , and a second selector 53 , but also a second calculation unit 54 and a third selector 55 .

[0156] The second calculation unit 54 is configured to calculate the product of the absolute value of the latest first output signal and a set positive constant to obtain a second intermediate value.

[0157] The third selector 55 is configured to select one of the second intermediate value and the second preset value as a rate change value to be output according to the second signal.

[0158] In some embodiments, the control module 45 includes a third calculation unit and a first adjustment module.

[0159] The third calculation unit is configured to calculate the difference between the power setting value and the actual power value to obtain a first difference.

[0160] The first regulating module is configured to regulate the guide vane opening of the pump-turbine according to the first difference through the first feedback controller.

[0161] In some embodiments, the control module 45 includes not only a third calculation unit and a first adjustment module, but also a determination module, a fourth calculation unit, a fifth calculation unit and a second adjustment module.

[0162] The determination module is configured to determine the distribution speed according to the distribution power distributed by the automatic power generation control system.

[0163] The fourth calculation unit is configured to calculate the sum of the distribution speed and the primary frequency modulation speed to obtain a speed setting value.

[0164] The fifth calculation unit is configured to calculate a difference between the rotational speed setting value and the actual rotational speed to obtain a second difference.

[0165] The second regulating module is configured to control the AC excitation control system to regulate the rotation speed of the pump-turbine according to the second difference through the second feedback controller.

[0166] It can be understood that the specific implementation details of the collaborative control device provided in the embodiment of the present disclosure can refer to the specific details of the collaborative control method embodiment of the first aspect mentioned above, and will not be repeated here.

[0167] In a third aspect, an embodiment of the present disclosure further provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the method described in any one of the first aspects is implemented.

[0168] Specifically, Figure 7 A schematic diagram of the physical structure of an electronic device provided by an embodiment of the present invention, such as Figure 7 As shown, the electronic device 003 includes a processor 301, a memory 302 and a bus 303. The processor 301 and the memory 302 communicate with each other via the bus 303.

[0169] The processor 301 is used to call the program instructions in the memory 302 to execute the methods provided by the above method embodiments.

[0170] In a fourth aspect, an embodiment of the present disclosure further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program of the method described in any one of the first aspects above.

[0171] In a fifth aspect, an embodiment of the present disclosure further provides a computer program product, comprising a computer program / instructions, which, when executed by a processor, implement the steps of any one of the methods described in the first aspect above.

[0172] Those skilled in the art will appreciate that the embodiments of the present disclosure may be provided as methods, systems, or computer program products. Therefore, the present disclosure may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present disclosure may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0173] The present disclosure is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present disclosure. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of the processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0174] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0175] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0176] The present disclosure uses specific embodiments to illustrate the principles and implementation methods of the present disclosure. The description of the above embodiments is only used to help understand the method of the present disclosure and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present disclosure, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present disclosure.

Claims

1. A primary frequency regulation coordinated control method based on a double-fed variable pumped storage unit, characterized in that: The method comprises: Collecting the operating parameters of the double-fed variable pumped storage unit and the grid frequency of the grid system in real time, wherein the operating parameters include the actual power value and the actual speed value of the pump turbine; For each collected operation parameter and grid frequency, the following operations are performed: If the grid frequency exceeds the set dead zone, generating a frequency modulation power according to the grid frequency; generating a power setting value according to the primary frequency regulation power and the allocated power allocated by the automatic power generation control system; generating a primary frequency modulation speed according to the primary frequency modulation power, the power setting value and the actual power value; The guide vane opening of the pump-turbine is adjusted by a first feedback controller according to the power setting value and the actual power value, and the AC excitation control system is controlled by a second feedback controller to adjust the speed of the pump-turbine according to the allocated power allocated by the automatic power generation control system, the primary frequency modulation speed and the actual speed of the pump-turbine; The step of generating a primary frequency modulation speed according to the primary frequency modulation power, the power setting value and the actual power value comprises: Determine whether the absolute value of the primary frequency modulation power is greater than 0, obtain a first determination result, and generate a first pulse signal according to the first determination result; Determine whether the difference between the power setting value and the actual power value is within a first set value range, obtain a second determination result, and generate a second pulse signal according to the second determination result; Inputting the first pulse signal into the S terminal of the first trigger, and inputting the second pulse signal into the R terminal of the first trigger, to obtain a first signal output by the first trigger; Inputting the second pulse signal into the S terminal of the second flip-flop, and inputting the first pulse signal into the R terminal of the second flip-flop, to obtain a second signal output by the second flip-flop; Obtaining a speed change value and a rate setting value according to the first signal and the second signal; According to the speed change value and the rate setting value, the primary frequency modulation speed is obtained; The obtaining a rate change value according to the first signal and the second signal includes: Input the first signal as the first control signal of the first selector into the first selector, and input the primary frequency modulation power at the current moment and the first output signal of the first selector at the current moment into the first selector respectively, so that the first selector selects one of the primary frequency modulation power at the current moment and the first output signal at the current moment as the latest first output signal to be output; Calculate the product of the absolute value of the latest first output signal and a set positive constant to obtain a second intermediate value; inputting the second signal into the third selector as a third control signal of the third selector, and inputting the second intermediate value and the second preset value into the third selector, so that the third selector selects one of the second intermediate value and the second preset value as the rate change value to be output; The speed change rate of the primary frequency modulation speed is fast when the primary frequency modulation starts to occur, and as the power and speed of the water pump and water machine are adjusted, the primary frequency modulation speed gradually decreases, and finally the primary frequency modulation speed returns to 0.

2. The method according to claim 1, characterized in that Obtaining a rotation speed change value according to the first signal and the second signal includes: Input the first signal as the first control signal of the first selector into the first selector, and input the primary frequency modulation power at the current moment and the first output signal of the first selector at the current moment into the first selector respectively, so that the first selector selects one of the primary frequency modulation power at the current moment and the first output signal at the current moment as the latest first output signal to be output; Calculate the product of the latest first output signal and a set negative constant to obtain a first intermediate value; The second signal is input into the second selector as a second control signal of the second selector, and the first intermediate value and 0 are input into the second selector, so that the second selector selects one of the first intermediate value and 0 as the rotation speed change value to be output.

3. The method according to claim 1, characterized in that The step of adjusting the guide vane opening of the pump turbine according to the power setting value and the actual power value by the first feedback controller includes: Calculating a difference between the power setting value and the actual power value to obtain a first difference; The guide vane opening of the pump turbine is adjusted according to the first difference by the first feedback controller.

4. The method according to claim 1, characterized in that: The method controls the AC excitation control system to adjust the speed of the pump-turbine according to the allocated power allocated by the automatic power generation control system, the primary frequency modulation speed and the actual speed of the pump-turbine through a second feedback controller, including: determining a distribution speed according to the distribution power distributed by the automatic power generation control system; Calculating the sum of the distribution speed and the primary frequency modulation speed to obtain a speed setting value; Calculating a difference between the speed setting value and the actual speed to obtain a second difference; The second feedback controller controls the AC excitation control system to adjust the rotation speed of the pump turbine according to the second difference.

5. A primary frequency regulation coordinated control device based on a double-fed variable pumped storage unit, characterized in that: The device comprises: A collection module is configured to collect the operating parameters of the double-fed variable pumped storage unit and the grid frequency of the power grid system in real time, wherein the operating parameters include the actual power value and the actual speed value of the pump turbine; A first calculation module is configured to generate a primary frequency modulation power according to the grid frequency when the grid frequency exceeds a set dead zone; A second calculation module is configured to generate a power setting value according to the primary frequency regulation power and the allocated power allocated by the automatic power generation control system; A third calculation module is configured to generate a primary frequency modulation speed according to the primary frequency modulation power, the power setting value and the actual power value; The control module is configured to adjust the guide vane opening of the pump-turbine according to the power setting value and the actual power value through a first feedback controller, and control the AC excitation control system to adjust the speed of the pump-turbine according to the allocated power allocated by the automatic power generation control system, the primary frequency modulation speed and the actual speed of the pump-turbine through a second feedback controller; The third calculation module includes: A first judgment module is configured to judge whether the absolute value of the primary frequency modulation power is greater than 0, obtain a first judgment result, and generate a first pulse signal according to the first judgment result; a second judgment module, configured to judge whether the difference between the power setting value and the actual power value is within a set value range, obtain a second judgment result, and generate a second pulse signal according to the second judgment result; A first trigger, comprising a first S terminal and a first R terminal, configured to generate a first signal according to the first pulse signal inputted from the first S terminal and the second pulse signal inputted from the first R terminal; A second trigger, comprising a second S terminal and a second R terminal, configured to generate a second signal according to the second pulse signal inputted by the second S terminal and the first pulse signal inputted by the second R terminal; A first calculation submodule is configured to obtain a rotation speed change value and a rate setting value according to the first signal and the second signal; A second calculation submodule is configured to obtain the primary frequency modulation speed according to the speed change value and the rate setting value; The first calculation submodule also includes: A second calculation unit is configured to calculate the product of the absolute value of the latest first output signal and a set positive constant to obtain a second intermediate value; a third selector, configured to select one of the second intermediate value and the second preset value as a rate change value to output according to the second signal; A first selector is configured to select one of the primary frequency modulation power at a current moment and the first output signal of the first selector at a current moment as the latest first output signal to be output according to the first signal; A first calculation unit is configured to calculate the product of the latest first output signal and a set negative constant to obtain a first intermediate value; a second selector, configured to select one of the first intermediate value and 0 as a rotation speed change value to output according to the second signal; The speed change rate of the primary frequency modulation speed is fast when the primary frequency modulation starts to occur, and as the power and speed of the water pump and water machine are adjusted, the primary frequency modulation speed gradually decreases, and finally the primary frequency modulation speed returns to 0.

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

7. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program for executing the method according to any one of claims 1 to 4.

8. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the steps of the method according to any one of claims 1 to 4 are implemented.

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