Hydrogen energy storage energy regulation system and method considering transient reactive power support

Abstract

The application discloses a hydrogen energy storage energy regulation system and a regulation method, which comprehensively consider the operation state of a power system, the voltage change of a grid-connected point and the hydrogen capacity of a hydrogen storage tank, and the regulation method comprises a steady-state regulation mode, a semi-steady-state regulation mode and a transient-state regulation mode, and the hydrogen energy storage energy regulation system comprises a water electrolysis hydrogen production load and a hydrogen fuel cell and is connected to a wind farm public connection point. When the power system is stably operated, the system enters the steady-state regulation mode to realize peak shaving and valley filling. When the voltage of the power system fluctuates, the system enters the semi-steady-state regulation mode to realize peak shaving and valley filling and reactive power support. When the voltage of the power system is temporarily lowered, the system enters the transient-state regulation mode, and through independent and coordinated control of the water electrolysis hydrogen production load, the active power output of the hydrogen fuel cell and the reactive power output of the hydrogen fuel cell, effective suppression of power fluctuation and rapid compensation of dynamic reactive power are realized, and the reactive power voltage support of the power grid and the effective suppression of the power fluctuation of the wind farm under emergency conditions are realized.

Description

TECHNICAL FIELD

[0001] The application relates to a hydrogen energy storage energy regulation system and a regulation method considering transient reactive power support, and belongs to the technical field of energy storage and new energy power system regulation. BACKGROUND

[0002] Renewable energy has the disadvantages of intermittency and instability, although there are renewable energy resources all over the world, many of which cannot provide energy all day long, for example, photovoltaic power generation can only provide electric energy in the daytime, and wind power can only provide electric energy under the condition of wind, and it is difficult to continuously and stably provide electric energy. Therefore, certain energy storage is needed to smooth the intermittent renewable energy. In addition, during the fault period of the renewable energy power generation such as wind power and photovoltaic power, it is difficult to support the system reactive power, and the renewable energy such as wind power and photovoltaic power may be caused to exit operation due to the fault of the power grid. SUMMARY

[0003] The application aims at overcoming the defects in the prior art, and provides a hydrogen energy storage energy regulation system and a regulation method considering transient reactive power support. The hydrogen energy storage system is configured on the side of the wind farm, the smooth output of the wind farm power is realized, the transient reactive power support of the wind farm in the voltage sag process is realized, and the low voltage ride through process is passed.

[0004] To achieve the above-mentioned purpose, the application adopts the following technical scheme:

[0005] In a first aspect, the application provides a hydrogen energy storage energy regulation system considering transient reactive power support, which comprises a wind farm, a hydrogen energy storage system and an energy control system.

[0006] The hydrogen energy storage system comprises a hydrogen fuel cell system and a hydrogen production system, and is provided with an electric energy transmission channel between each two of the wind farm and the hydrogen energy storage system.

[0007] The energy control system regulates the hydrogen energy storage system according to the voltage of the wind farm point of common coupling when detecting the voltage fluctuation of the wind farm point of common coupling, so as to realize the different active power and reactive power output of the hydrogen energy storage system.

[0008] Further, the energy control system regulates the hydrogen energy storage system according to the voltage of the wind farm point of common coupling, which comprises:

[0009] When the voltage of the wind farm point of common coupling is in the steady state voltage range, the steady state regulation mode is entered, the hydrogen energy storage system realizes peak clipping and valley filling according to the active power of the wind farm and the hydrogen capacity of the hydrogen storage tank, so as to realize the smooth output of the active power of the wind farm.

[0010] When the voltage of the wind farm point of common coupling is in the semi-stable voltage range, the semi-stable regulation mode is entered, and the hydrogen energy storage system comprehensively considers the required reactive power shortage of the voltage, the active power condition of the wind farm and the hydrogen gas capacity of the hydrogen storage tank, and preferentially realizes peak shaving and valley filling of the active power of the wind farm, so that the active power of the wind farm is smoothly output, and when the power is surplus, the hydrogen energy storage system provides transient reactive power support to the wind farm, and realizes low voltage ride through.

[0011] When the voltage of the wind farm point of common coupling is in the transient voltage range, the transient regulation mode is entered, the hydrogen fuel cell system in the hydrogen energy storage system is used for transient reactive power support of the wind farm, low voltage ride through is realized, and the hydrogen production system considers whether to produce hydrogen according to the hydrogen gas capacity of the hydrogen storage tank, so as to absorb the short-time excessive power of the wind farm and smooth the output power of the wind farm.

[0012] Further, in the steady state regulation mode:

[0013] When the hydrogen gas capacity of the hydrogen storage tank is in the normal range, the hydrogen fuel cell system and the hydrogen production system smooth the fluctuating power output by the wind farm, so as to more friendly adapt to the power system.

[0014] (1)

[0015] In the formula, P out is the active power injected into the power grid by the wind farm through the hydrogen energy storage system, P wind is the actual active power output by the wind farm, , f c is the cut-off frequency of the low-pass filter;

[0016] When smoothing the output power of the wind farm, the active power emitted or absorbed by the hydrogen energy storage system is:

[0017] (2)

[0018] In the formula, P h2 is the active power emitted or absorbed by the hydrogen energy storage system, when P h2 > 0, the hydrogen fuel cell system in the hydrogen energy storage system starts to act and emits active power, and when P h2 < 0, the hydrogen production system in the hydrogen energy storage system starts to act and absorbs active power.

[0019] Further, in the semi-stable regulation mode:

[0020] When the system finds that the voltage of the point of common coupling is in the semi-stable voltage range, the hydrogen energy storage system preferentially smooths the active fluctuating power output by the wind farm according to formula (1) and formula (2) to more friendly adapt to the power system, and when the power is surplus, the hydrogen energy storage system realizes transient reactive power support to the wind farm and low voltage ride through;

[0021] The reactive power that the wind farm can output at this time can be expressed as:

[0022] (3)

[0023] In the formula, Q h2 This refers to the reactive power that a hydrogen energy storage system can generate.

[0024] Within the semi-steady-state voltage range, the required reactive power for a wind farm can be obtained using a PI controller and voltage fluctuation values.

[0025] (4)

[0026] In the formula, Q h2_want k is the reactive power required by the hydrogen energy storage system for the system. p and k i ΔU is the control parameter of the PI controller. pcc This is the difference between the instantaneous voltage at the point of common coupling of the wind farm and the rated voltage.

[0027] At this point, for Q h2 and Q h2_want Compare, if Q h2_want >Q h2 Then Q h2 All outputs are ineffective; if Q h2_want <Q h2 In this case, the hydrogen fuel cell system only emits Q. h2_want .

[0028] Furthermore, in the transient control mode, when the voltage at the point of common coupling of the wind farm is within the transient voltage range, the hydrogen fuel cell system in the hydrogen energy storage system generates all reactive power to support the transient reactive power of the wind farm, thereby achieving low voltage ride-through of the wind farm. At the same time, the hydrogen production system considers whether to produce hydrogen based on the hydrogen capacity of the hydrogen storage tank to absorb the short-term excessive power of the wind farm and smooth the output power of the wind farm.

[0029] At this time, the reactive power generated by the hydrogen fuel cell system is:

[0030] (5)

[0031] If the hydrogen storage tank capacity is within the normal range, the fluctuating power output of the wind farm can be smoothed using the hydrogen production system according to equations (1) and (2). Since only the hydrogen production system absorbs power, it can only be used at P h2 When <0, the action is performed.

[0032] Furthermore, constraints related to hydrogen energy storage systems include power constraints of hydrogen production systems, capacity constraints of hydrogen storage tanks, and power constraints of hydrogen fuel cell systems.

[0033] Maximum and minimum active power constraints for hydrogen fuel cell systems:

[0034] (6)

[0035] In the formula, P h2 For the instantaneous active power output of the hydrogen fuel cell system, P h2_max P represents the maximum active power of the hydrogen fuel cell system. h2_min This represents the minimum active power of a hydrogen fuel cell system.

[0036] Hydrogen storage tank capacity constraints in hydrogen production systems:

[0037] (7)

[0038] In the formula, V h2 V is the instantaneous hydrogen storage capacity of the hydrogen production system. h2_max This is the maximum capacity of the hydrogen storage tank;

[0039] Power constraints of hydrogen fuel cell systems:

[0040] (8)

[0041] In the formula, Q h2 For the instantaneous reactive power output of the hydrogen fuel cell system, S h2_max This represents the maximum apparent power of the hydrogen fuel cell system.

[0042] Furthermore, the steady-state voltage range, semi-steady-state voltage range, and transient voltage range are defined according to the technical regulations for wind farm access to the power system.

[0043] Secondly, the present invention also provides a regulation method for a hydrogen-containing energy storage system, based on a hydrogen-containing energy storage system, the system comprising a wind farm and a hydrogen energy storage system; the hydrogen energy storage system comprising a hydrogen fuel cell system and a hydrogen production system, and having power transmission channels between each of the wind farm and the system.

[0044] The method includes:

[0045] Obtain grid voltage data from the wind farm's point of common coupling;

[0046] The hydrogen energy storage system is regulated based on grid voltage data.

[0047] Furthermore, methods for regulating hydrogen energy storage systems based on grid voltage data include:

[0048] Step A: Obtain the voltage at the wind farm's point of common coupling;

[0049] Step B: Determine whether the voltage at the point of common coupling of the wind farm is within the steady-state voltage range. If so, enter the steady-state control mode and regulate the hydrogen energy storage under the steady-state control mode. If not, proceed to step C.

[0050] Step C: Determine whether the voltage at the point of common coupling of the wind farm is within the semi-steady-state voltage range. If so, enter the semi-steady-state control mode and regulate the hydrogen energy storage under the semi-steady-state control mode. If not, enter the transient control mode and regulate the hydrogen energy storage under the transient control mode.

[0051] Furthermore, methods for regulating hydrogen energy storage under steady-state control modes include:

[0052] Step 0: Enter steady-state control mode;

[0053] Step 1: Determine whether the active power of the hydrogen energy storage system is greater than 0 according to equation (9);

[0054] (9)

[0055] Step 2-1: If yes, determine whether the hydrogen capacity in the hydrogen storage tank is greater than 0. If yes, the hydrogen fuel cell system generates active power according to formula (9). If not, return to step 0.

[0056] Step 2-2: If not, determine whether the hydrogen storage tank is full. If not, the hydrogen production system will produce hydrogen according to formula (9) as the load. If so, return to step 0.

[0057] Furthermore, methods for regulating hydrogen energy storage under semi-steady-state control mode include:

[0058] Step 0: Enter semi-steady-state control mode;

[0059] Step 1: Determine whether the active power of the hydrogen energy storage system is greater than 0 according to equation (9);

[0060] Step 2-1: If yes, determine whether the hydrogen capacity in the hydrogen storage tank is greater than 0. If yes, the hydrogen fuel cell system generates active power according to formula (2). If not, return to step 0.

[0061] Step 2-2: If not, determine whether the hydrogen storage tank is full. If not, the hydrogen production system will produce hydrogen according to formula (2) as the load. If so, return to step 0.

[0062] Step 3: Apply equations (10) and (11) to Q. h2 and Q h2_want Comparison, Q h2_want Is it greater than Q? h2 If it is greater than , then the hydrogen fuel cell system outputs reactive power Q.h2 If it is less than , then the hydrogen fuel cell system outputs reactive power Q. h2_want ;

[0063] The reactive power that the wind farm can output at this time can be expressed as:

[0064] (10)

[0065] In the formula, Q h2 This refers to the reactive power that a hydrogen energy storage system can generate.

[0066] Within the semi-steady-state voltage range, the required reactive power for a wind farm can be obtained using a PI controller and voltage fluctuation values.

[0067] (11)

[0068] In the formula, Q h2_want k is the reactive power required by the hydrogen energy storage system for the system. p and k i ΔU is the control parameter of the PI controller. pcc This is the difference between the instantaneous voltage at the point of common coupling of the wind farm and the rated voltage.

[0069] Furthermore, methods for regulating hydrogen energy storage under transient regulation modes include:

[0070] Step 0: Enter transient control mode;

[0071] Step 1: Determine if the hydrogen capacity in the hydrogen storage tank is greater than 0. If so, the reactive power Q generated by the hydrogen fuel cell system is calculated according to equation (12). h2 If not, return to step 0;

[0072] At this time, the reactive power generated by the hydrogen fuel cell system is:

[0073] (12)

[0074] Step 2: Determine whether the active power of the hydrogen energy storage system is greater than 0 according to equation (9). If it is, proceed to step 3; otherwise, return to step 0.

[0075] Step 3: Determine whether the hydrogen storage tank is full. If not, the hydrogen production system will produce hydrogen according to formula (9) as the load. If so, return to step 0.

[0076] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0077] This invention, by configuring a hydrogen energy storage system at the wind farm side and co-producing with the wind farm, can smooth the fluctuating output of the wind farm, achieving peak shaving and valley filling, and reducing the volatility of wind farm output. Simultaneously, when voltage dips occur during grid connection, the hydrogen energy storage can control the generation of reactive power to support the grid voltage, helping the wind farm overcome the low-voltage ride-through phase. Furthermore, the produced hydrogen can be sold to generate profit. Therefore, this invention not only more effectively alleviates the problem of renewable energy integration and improves resource utilization efficiency, but also provides reactive power support under transient conditions, ensuring the grid-connected operation of wind farms under grid fault conditions, while simultaneously protecting the economic interests of the wind farms.

[0078] Meanwhile, hydrogen energy storage systems offer stable energy storage and mature technology, enabling them to reliably store energy. Attached Figure Description

[0079] Figure 1 The diagram shown is a schematic diagram of the wind farm-side hydrogen energy storage system of the present invention.

[0080] Figure 2 The diagram shows a schematic of the energy regulation strategy for a hydrogen energy storage system.

[0081] Figure 3 The diagram shows a hydrogen energy storage system in steady-state control mode.

[0082] Figure 4 The diagram shows a hydrogen energy storage system in a semi-steady-state control mode.

[0083] Figure 5 The diagram shows a hydrogen energy storage system in transient control mode. Detailed Implementation

[0084] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0085] Combination Figure 1 and Figure 2 This embodiment introduces a hydrogen energy storage energy regulation system and method that considers transient reactive power support. By configuring a certain hydrogen energy storage system on the wind farm side, smooth power output from the wind farm can be achieved, providing transient reactive power support for the wind farm during voltage dips and helping it overcome low-voltage ride-through. The hydrogen energy storage energy regulation system includes a wind farm, a hydrogen energy storage system, and an energy control system.

[0086] The hydrogen energy storage system consists of two parts: a hydrogen fuel cell system and a hydrogen production system, and each part has an electrical transmission channel between it and the wind farm.

[0087] When the energy control system detects voltage fluctuations at the wind farm's point of common coupling, it determines to enter different control modes and achieves different active and reactive power outputs.

[0088] In this invention, the hydrogen energy storage energy regulation system that considers transient reactive power support will take into account the operating status of the new energy power system, the voltage change characteristics of the grid connection point, and the hydrogen capacity of the hydrogen storage tank. When the voltage at the grid connection point drops, it will provide active and reactive power support according to demand.

[0089] When the voltage at the point of common coupling of the wind farm is within the steady-state voltage range, it enters the steady-state control mode. Based on the active power of the wind farm and the hydrogen capacity of the hydrogen storage tank, the hydrogen energy storage system can smooth the peak and valley of the active power of the wind farm, so that the active power of the wind farm can be output smoothly.

[0090] When the voltage at the point of common coupling of the wind farm is within the semi-steady-state voltage range, it enters the semi-steady-state control mode. Taking into account the reactive power deficit required for voltage, the active power of the wind farm, and the hydrogen capacity of the hydrogen storage tank, the hydrogen energy storage system prioritizes peak shaving and valley filling for the active power of the wind farm, so that the active power of the wind farm can be output smoothly. When there is a power surplus, it provides transient reactive power support for the wind farm and realizes low voltage ride-through.

[0091] When the voltage at the point of common coupling of the wind farm is within the transient voltage range, it enters the transient control mode. The hydrogen fuel cell system in the hydrogen energy storage system is used entirely for the transient reactive power support of the wind farm to achieve low voltage ride-through. At the same time, the hydrogen production system considers whether to produce hydrogen based on the hydrogen capacity of the hydrogen storage tank to absorb the short-term excessive power of the wind farm and smooth the output power of the wind farm.

[0092] The steady-state, semi-steady-state, and transient ranges described in this invention can be defined by technical personnel according to relevant standards and specifications such as the technical regulations for wind farm connection to the power system. For example, the steady-state range can be set to 0.98 pu to 1.02 pu using the per-unit value calculation method, the semi-steady-state range can be set to 0.9 pu to 0.98 pu and 1.02 pu to 1.1 pu using the per-unit value calculation method, and the transient range can be set to below 0.9 pu or above 1.1 pu using the per-unit value calculation method.

[0093] The specific steps are as follows:

[0094] Step 0: Commissioning of the hydrogen energy storage system;

[0095] Step 0-1: Determine the status of the hydrogen production equipment and hydrogen fuel cell in the hydrogen energy storage system. If they are in good condition, proceed to step 0-2; otherwise, return to step 0.

[0096] Step 0-2: Hydrogen energy storage system on standby;

[0097] Step 1: Determine the voltage U at the point of common coupling of the wind farm. pcc Is it at the steady-state voltage critical value U? grid-2-down and U grid-1-up If the condition is met, then enter steady-state control mode; otherwise, proceed to step 2.

[0098] Step 2: Determine the voltage U at the point of common coupling of the wind farm. pcc If the semi-steady-state voltage threshold is between Ugrid-1-up and Ugrid-2-up, and between Ugrid-1-down and Ugrid-2-down, then enter the semi-steady-state control mode; otherwise, enter the transient control mode.

[0099] Combination Figure 3 To regulate hydrogen energy storage under steady-state control mode.

[0100] When entering steady-state control mode, the principle is to use a first-order Butterworth high-pass filter to operate the hydrogen fuel cell system and hydrogen production system, and to smooth the fluctuating power output of the wind farm, so as to better adapt to the power system.

[0101] (1)

[0102] In the formula, P out P represents the active power injected into the grid from the wind farm after being smoothed by the hydrogen energy storage system. wind The actual active power generated by the wind farm. f c This is the cutoff frequency of the low-pass filter. For example, if it is necessary to smooth out fluctuations of 0.01Hz and above, the cutoff frequency can be selected as 0.01Hz.

[0103] When the wind farm outputs power, the active power generated or absorbed by the hydrogen energy storage system is:

[0104] (2)

[0105] In the formula, P h2 Active power generated or absorbed by the hydrogen energy storage system.

[0106] At this point, the system determines P based on the wind farm's output after filtering. h2 The state.

[0107] When P h2 When the hydrogen capacity in the hydrogen storage tank is greater than 0, the hydrogen fuel cell system in the hydrogen energy storage system starts to operate and generate active power.

[0108] When P h2When the value is less than 0, and it is determined that the hydrogen storage tank is not full, the hydrogen production system in the hydrogen energy storage system starts to operate and absorb active power.

[0109] The specific steps are as follows:

[0110] Step 0: Enter steady-state control mode;

[0111] Step 1: Determine whether the active power of the hydrogen energy storage system is greater than 0 according to equation (2);

[0112] Step 2-1: If yes, determine whether the hydrogen capacity in the hydrogen storage tank is greater than 0. If yes, the hydrogen fuel cell system generates active power according to formula (2). If not, return to step 0.

[0113] Step 2-2: If not, determine whether the hydrogen storage tank is full. If not, the hydrogen production system will produce hydrogen according to formula (2) as the load. If so, return to step 0.

[0114] Combination Figure 4 To regulate hydrogen energy storage under semi-steady-state control mode.

[0115] When the system detects that the point of common coupling voltage of the wind farm is within the semi-steady-state voltage range, the hydrogen energy storage system prioritizes smoothing the fluctuating power output of the wind farm according to equations (1) and (2) to better adapt to the power system. Simultaneously, when there is power surplus, it provides transient reactive power support and low-voltage ride-through for the wind farm. The system's handling at this time is similar to... Figure 3 As stated above.

[0116] The reactive power that the wind farm can output at this time can be expressed as:

[0117] (3)

[0118] In the formula, Q h2 This refers to the reactive power that a hydrogen energy storage system can generate.

[0119] Within the semi-steady-state voltage range, the required reactive power for a wind farm can be obtained using a PI controller and voltage fluctuation values.

[0120] (4)

[0121] In the formula, Q h2_want k is the reactive power required by the hydrogen energy storage system for the system. p and k i ΔU is the control parameter of the PI controller. pcc This is the difference between the instantaneous voltage at the point of common coupling of the wind farm and the rated voltage.

[0122] At this point, for Q h2 and Qh2_want Compare, if Q h2_want >Q h2 Then Q h2 All outputs are ineffective; if Q h2_want <Q h2 In this case, the hydrogen fuel cell system only emits Q. h2_want .

[0123] The specific steps are as follows:

[0124] Step 0: Enter semi-steady-state control mode;

[0125] Step 1: Determine whether the active power of the hydrogen energy storage system is greater than 0 according to equation (2);

[0126] Step 2-1: If yes, determine whether the hydrogen capacity in the hydrogen storage tank is greater than 0. If yes, the hydrogen fuel cell system generates active power according to formula (2). If not, return to step 0.

[0127] Step 2-2: If not, determine whether the hydrogen storage tank is full. If not, the hydrogen production system will produce hydrogen according to formula (2) as the load. If so, return to step 0.

[0128] Step 3: Apply equations (3) and (4) to Q h2 and Q h2_want Comparison, Q h2_want Is it greater than Q? h2 If it is greater than , then the hydrogen fuel cell system outputs reactive power Q. h2 If it is less than , then the hydrogen fuel cell system outputs reactive power Q. h2_want .

[0129] Combination Figure 5 To regulate hydrogen energy storage under transient control mode.

[0130] When the system detects that the voltage at the point of common coupling of the wind farm is within the transient voltage range, the hydrogen fuel cell system in the hydrogen energy storage system generates all reactive power to support the transient reactive power of the wind farm, thus enabling the wind farm to ride through low voltage.

[0131] At this time, the reactive power generated by the hydrogen fuel cell system is:

[0132] (5)

[0133] At this point, the system determines P based on the wind farm's output after filtering. h2 The state.

[0134] When P h2 When the hydrogen capacity in the hydrogen storage tank is greater than 0, the hydrogen fuel cell system in the hydrogen energy storage system starts to operate and generate active power.

[0135] When P h2 When the value is less than 0, the system does not perform any action.

[0136] The specific steps are as follows:

[0137] Step 0: Enter transient control mode;

[0138] Step 1: Determine if the hydrogen capacity in the hydrogen storage tank is greater than 0. If so, then according to equation (5), the hydrogen fuel cell system outputs reactive power Q. h2 If not, return to step 0;

[0139] Step 2: Determine whether the active power of the hydrogen energy storage system is greater than 0 according to formula (2). If it is, proceed to step 3; otherwise, return to step 0.

[0140] Step 3: Determine whether the hydrogen storage tank is full. If not, the hydrogen production system will produce hydrogen according to formula (2) as the load. If so, return to step 0.

[0141] Combination Figures 1-5 Constraints related to hydrogen energy storage systems include power constraints of hydrogen production systems, capacity constraints of hydrogen storage tanks, and power constraints of hydrogen fuel cell systems.

[0142] Maximum and minimum active power constraints for hydrogen fuel cell systems:

[0143] (6)

[0144] In the formula, P h2 For the instantaneous active power output of the hydrogen fuel cell system, P h2_max P represents the maximum active power of the hydrogen fuel cell system. h2_min This represents the minimum active power of a hydrogen fuel cell system.

[0145] Hydrogen storage tank capacity constraints in hydrogen production systems:

[0146] (7)

[0147] In the formula, V h2 V is the instantaneous hydrogen storage capacity of the hydrogen production system. h2_max This is the maximum capacity of the hydrogen storage tank;

[0148] Power constraints of hydrogen fuel cell systems:

[0149] (8)

[0150] In the formula, Q h2 For the instantaneous reactive power output of the hydrogen fuel cell system, S h2_max This represents the maximum apparent power of the hydrogen fuel cell system.

[0151] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied 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.

[0152] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0153] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0154] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0155] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A hydrogen energy storage energy regulation system considering transient reactive power support, characterized in that, This includes wind farms, hydrogen energy storage systems, and energy control systems; The hydrogen energy storage system includes a hydrogen fuel cell system and a hydrogen production system, and there are separate power transmission channels between the system and the wind farm. When the energy control system detects voltage fluctuations at the point of common coupling (PCC) of the wind farm, it adjusts the hydrogen energy storage system according to the PCC voltage to achieve different active and reactive power outputs of the hydrogen energy storage system. The energy control system regulates the hydrogen energy storage system based on the voltage at the wind farm's point of common coupling, including: When the voltage at the point of common coupling of the wind farm is within the steady-state voltage range, it enters the steady-state control mode. Based on the active power of the wind farm and the hydrogen capacity of the hydrogen storage tank, the hydrogen energy storage system can achieve peak shaving and valley filling of the active power of the wind farm, so that the active power of the wind farm can be output smoothly. When the voltage at the point of common coupling of the wind farm is within the semi-steady-state voltage range, it enters the semi-steady-state control mode. Taking into account the reactive power deficit required for the voltage, the active power of the wind farm, and the hydrogen capacity of the hydrogen storage tank, the hydrogen energy storage system prioritizes peak shaving and valley filling for the active power of the wind farm, so that the active power of the wind farm can be output smoothly. When there is a power surplus, it provides transient reactive power support for the wind farm and realizes low voltage ride-through. When the voltage at the point of common coupling of the wind farm is within the transient voltage range, it enters the transient control mode. The hydrogen fuel cell system in the hydrogen energy storage system is used entirely for the transient reactive power support of the wind farm to achieve low voltage ride-through. At the same time, the hydrogen production system considers whether to produce hydrogen based on the hydrogen capacity of the hydrogen storage tank in order to absorb the short-term excessive power of the wind farm and smooth the output power of the wind farm. In the aforementioned steady-state control mode: When the hydrogen storage tank has a hydrogen capacity within the normal range, the hydrogen fuel cell system and hydrogen production system smooth out the fluctuating power output from the wind farm to better adapt to the power system. （1） In the formula, P out P represents the active power injected into the grid from the wind farm after being smoothed by the hydrogen energy storage system. wind The actual active power generated by the wind farm. f c This is the cutoff frequency of the low-pass filter; When the wind farm outputs power, the active power generated or absorbed by the hydrogen energy storage system is: （2） In the formula, P h2 The active power generated or absorbed by the hydrogen energy storage system, when P h2 When P > 0, the hydrogen fuel cell system in the hydrogen energy storage system starts to operate and outputs active power. h2 When the value is less than 0, the hydrogen production system in the hydrogen energy storage system starts to operate and absorb active power. The steady-state voltage range is set to 0.98pu~1.02pu using the per-unit value calculation method, the semi-steady-state voltage range is set to 0.9pu~0.98pu and 1.02pu~1.1pu using the per-unit value calculation method, and the transient voltage range is set to below 0.9pu or above 1.1pu using the per-unit value calculation method.

2. The hydrogen energy storage and regulation system considering transient reactive power support according to claim 1, characterized in that, In the semi-steady-state control mode: When the system detects that the voltage at the point of common coupling is within the semi-steady-state voltage range, the hydrogen energy storage system prioritizes smoothing the active power fluctuations output by the wind farm according to equations (1) and (2) to better adapt to the power system. At the same time, when there is a power surplus, it can provide transient reactive power support and low voltage ride-through for the wind farm. The reactive power that the wind farm can output at this time can be expressed as: （3） In the formula, Q h2 S represents the reactive power that a hydrogen energy storage system can generate. h2 The apparent power of the hydrogen fuel cell system; Within the semi-steady-state voltage range, the required reactive power for a wind farm can be obtained using a PI controller and voltage fluctuation values. （4） In the formula, Q h2_want k is the reactive power required by the hydrogen energy storage system for the system. p and k i ΔU is the control parameter of the PI controller. pcc This is the difference between the instantaneous voltage at the point of common coupling of the wind farm and the rated voltage. At this point, for Q h2 and Q h2_want Compare, if Q h2_want >Q h2 Then Q h2 All outputs are ineffective; if Q h2_want <Q h2 In this case, the hydrogen fuel cell system only emits Q. h2_want .

3. The hydrogen energy storage and regulation system considering transient reactive power support according to claim 2, characterized in that, In the transient control mode, when the voltage of the wind farm's point of common coupling is within the transient voltage range, the hydrogen fuel cell system in the hydrogen energy storage system generates all reactive power to support the wind farm's transient reactive power and achieve low voltage ride-through of the wind farm. At the same time, the hydrogen production system considers whether to produce hydrogen based on the hydrogen capacity of the hydrogen storage tank in order to absorb the wind farm's short-term excessive power and smooth the wind farm's output power. At this time, the reactive power generated by the hydrogen fuel cell system is: （5） Among them, S h2_max This represents the maximum apparent power of the hydrogen fuel cell system. If the hydrogen storage tank capacity is within the normal range, the fluctuating power output of the wind farm can be smoothed using the hydrogen production system according to equations (1) and (2). Since only the hydrogen production system absorbs power, it can only be used at P h2 When <0, the action is performed.

4. The hydrogen energy storage and regulation system considering transient reactive power support according to claim 1, characterized in that, Constraints related to hydrogen energy storage systems include power constraints of hydrogen production systems, capacity constraints of hydrogen storage tanks, and power constraints of hydrogen fuel cell systems. Maximum and minimum active power constraints for hydrogen fuel cell systems: （6） In the formula, P h2 P represents the active power generated or absorbed by the hydrogen energy storage system. h2_max P represents the maximum active power of the hydrogen fuel cell system. h2_min This represents the minimum active power of a hydrogen fuel cell system. Hydrogen storage tank capacity constraints in hydrogen production systems: （7） In the formula, V h2 V is the instantaneous hydrogen storage capacity of the hydrogen production system. h2_max This is the maximum capacity of the hydrogen storage tank; Power constraints of hydrogen fuel cell systems: （8） In the formula, Q h2 S represents the reactive power that a hydrogen energy storage system can generate. h2_max This represents the maximum apparent power of the hydrogen fuel cell system.

5. A control method for a hydrogen energy storage system considering transient reactive power support, characterized in that, Based on the hydrogen energy storage and regulation system considering transient reactive power support as described in claim 1, the system includes a wind farm and a hydrogen energy storage system; the hydrogen energy storage system includes a hydrogen fuel cell system and a hydrogen production system, and each of the wind farm and the system is provided with an electrical transmission channel. The method includes: Obtain grid voltage data from the wind farm's point of common coupling; Regulate the hydrogen energy storage system based on grid voltage data; Methods for regulating hydrogen energy storage systems based on grid voltage data include: Step A: Obtain the voltage at the wind farm's point of common coupling; Step B: Determine whether the voltage at the point of common coupling of the wind farm is within the steady-state voltage range. If so, enter the steady-state control mode and regulate the hydrogen energy storage under the steady-state control mode. If not, proceed to step C. Step C: Determine whether the voltage at the point of common coupling of the wind farm is within the semi-steady-state voltage range. If so, enter the semi-steady-state control mode and regulate the hydrogen energy storage under the semi-steady-state control mode. If not, enter the transient control mode and regulate the hydrogen energy storage under the transient control mode. Methods for regulating hydrogen energy storage under steady-state control mode include: Step 0: Enter steady-state control mode; Step 1: Determine whether the active power of the hydrogen energy storage system is greater than 0 according to equation (9); （9） Step 2-1: If yes, determine whether the hydrogen capacity in the hydrogen storage tank is greater than 0. If yes, the hydrogen fuel cell system generates active power according to formula (9). If not, return to step 0. Step 2-2: If not, determine whether the hydrogen storage tank is full. If not, the hydrogen production system will produce hydrogen according to formula (9) as the load. If so, return to step 0.

6. The regulation method for a hydrogen energy storage system considering transient reactive power support according to claim 5, characterized in that, Methods for regulating hydrogen energy storage under semi-steady-state control mode include: Step 0: Enter semi-steady-state control mode; Step 1: Determine whether the active power of the hydrogen energy storage system is greater than 0 according to equation (9); Step 2-1: If yes, determine whether the hydrogen capacity in the hydrogen storage tank is greater than 0. If yes, the hydrogen fuel cell system generates active power according to formula (2). If not, return to step 0. Step 2-2: If not, determine whether the hydrogen storage tank is full. If not, the hydrogen production system produces hydrogen according to formula (2) as the load. If so, return to step 0. Step 3: Apply equations (10) and (11) to Q. h2 and Q h2_want Comparison, Q h2_want Is it greater than Q? h2 If it is greater than , then the hydrogen fuel cell system outputs reactive power Q. h2 If it is less than , then the hydrogen fuel cell system outputs reactive power Q. h2_want ; The reactive power that the wind farm can output at this time can be expressed as: （10） In the formula, Q h2 The reactive power that a hydrogen energy storage system can generate; Within the semi-steady-state voltage range, the required reactive power for a wind farm can be obtained using a PI controller and voltage fluctuation values. （11） In the formula, Q h2_want k is the reactive power required by the hydrogen energy storage system for the system. p and k i ΔU is the control parameter of the PI controller. pcc This is the difference between the instantaneous voltage at the point of common coupling of the wind farm and the rated voltage. and / or, Methods for regulating hydrogen energy storage under transient regulation modes include: Step 0: Enter transient control mode; Step 1: Determine if the hydrogen capacity in the hydrogen storage tank is greater than 0. If so, the reactive power Q generated by the hydrogen fuel cell system is calculated according to equation (12). h2 If not, return to step 0; At this time, the reactive power generated by the hydrogen fuel cell system is: （12） Step 2: Determine whether the active power of the hydrogen energy storage system is greater than 0 according to equation (9). If it is, proceed to step 3; otherwise, return to step 0. Step 3: Determine whether the hydrogen storage tank is full. If not, the hydrogen production system will produce hydrogen according to formula (9) as the load. If so, return to step 0.

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