A new energy power station and a high and low voltage fault ride-through control method thereof

Abstract

The application provides a new energy power station and a high and low voltage fault ride-through control method thereof. The method first determines the total reactive current required by the transformer input side when the new energy power station is in high and low voltage fault ride-through according to the rated current of the transformer input side; then determines the reactive current distribution amount of each power conversion module when the total reactive current requirement can be met and the sum of the active currents output by each power conversion module is maximum, so as to realize the adjustment of the control strategy of the new energy power station in high and low voltage fault ride-through; finally, the reactive current distribution amount is sent to the corresponding power conversion module, so that each power conversion module operates in the state of outputting the corresponding reactive current distribution amount in high and low voltage fault ride-through; and then sufficient reactive current is ensured to support the voltage of the power grid, and the active current is maximized to maintain the stability of the frequency as much as possible.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new energy power generation, in particular to a new energy power station and a high-low voltage fault ride-through control method thereof. BACKGROUND

[0002] When the new energy power station experiences high-low voltage fault ride-through, the wind power converter and the photovoltaic inverter in the power station will preferentially provide reactive current; however, due to the limited overload capacity of power electronic devices, the active current will inevitably be reduced. At this time, for the power grid, although the stability of the transient voltage is improved, there is a risk of frequency stability, and the pros and cons are considered. SUMMARY

[0003] Therefore, the present application provides a new energy power station and a high-low voltage fault ride-through control method thereof, so as to ensure sufficient reactive current and maximize the provision of active current when the new energy power station experiences high-low voltage fault ride-through.

[0004] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0005] The first aspect of the present application provides a high-low voltage fault ride-through control method of a new energy power station, at least two power conversion modules of new energy systems are arranged in front of a transformer in the new energy power station, and the high-low voltage fault ride-through control method comprises:

[0006] According to the rated current of the input side of the transformer, the total reactive current required by the input side of the transformer when the new energy power station experiences high-low voltage fault ride-through is determined;

[0007] According to the current output state of each power conversion module, the reactive current distribution amount of each power conversion module is determined when the demand for the total reactive current can be met and the sum of the active currents output by each power conversion module is maximum.

[0008] Each reactive current distribution amount is sent to the corresponding power conversion module, so that each power conversion module operates in the state of outputting the corresponding reactive current distribution amount during high-low voltage fault ride-through.

[0009] Optionally, according to the current output state of each power conversion module, the reactive current distribution amount of each power conversion module is determined when the demand for the total reactive current can be met and the sum of the active currents output by each power conversion module is maximum, comprising:

[0010] The current active current output by each power conversion module and the current voltage of the input side of the transformer are collected;

[0011] determining current active power of each of the power conversion modules;

[0012] determining the reactive current distribution amount of each of the power conversion modules, as a boundary condition, under the condition that the sum of the reactive current distribution amount of each of the power conversion modules is greater than or equal to the total reactive current, the active power that each of the power conversion modules can output under the corresponding reactive current distribution amount is less than or equal to the corresponding current active power when the high-low voltage fault ride-through is performed, and each of the reactive current distribution amounts is greater than or equal to zero, determining the corresponding reactive current distribution amount of each of the power conversion modules when the sum of the output active current is maximum.

[0013] Optionally, the current active current output by each of the power conversion modules and the current voltage at the input side of the transformer are collected, and the real-time or periodic execution is performed.

[0014] Optionally, according to the rated current of the input side of the transformer, the total reactive current required by the input side of the transformer during the high-low voltage fault ride-through of the new energy power station is determined, including:

[0015] The rated current of the transformer input side is converted according to the voltage ratio change of the transformer input side during the high-low voltage fault ride-through, and the preset proportion value between the dynamic reactive current ratio of the transformer input side and the voltage ratio change, to determine the total reactive current.

[0016] Optionally, the voltage ratio change is the difference between the preset ratio and the actual ratio, and the actual ratio is the ratio between the fault voltage and the rated voltage of the transformer input side during the high-low voltage fault ride-through;

[0017] When the actual ratio is less than the low voltage fault ride-through ratio, the preset ratio is the low voltage fault ride-through ratio, and the preset proportion value is a first proportion value; when the actual ratio is greater than the high voltage fault ride-through ratio, the preset ratio is the high voltage fault ride-through ratio, and the preset proportion value is a second proportion value.

[0018] Optionally, the reactive current distribution amount includes: under different preset fault voltages, the corresponding reactive current distribution value during the high-low voltage fault ride-through.

[0019] Optionally, the reactive current distribution amount includes: a calculation formula with the fault voltage during the high-low voltage fault ride-through as the independent variable.

[0020] The second aspect of the present application provides a new energy power station, comprising: a controller, a transformer, and at least two new energy systems and their corresponding power conversion modules; wherein,

[0021] Each of the new energy systems is connected in parallel to the input side of the transformer through its own power conversion module.

[0022] The output side of the transformer is connected to a power grid through a booster station;

[0023] The controller is in communication connection with the transformer and each power conversion module respectively, and is configured to execute the high and low voltage fault ride-through control method of the new energy power station as described in any one of the first aspect.

[0024] Optionally, the new energy system is a photovoltaic system, a wind power system or a battery system.

[0025] Optionally, the power conversion module of the photovoltaic system comprises at least one photovoltaic inverter, whose DC side is connected to a corresponding photovoltaic string in the photovoltaic system, and whose AC side is connected to the input side of the transformer.

[0026] The power conversion module of the wind power system comprises at least one wind power converter, whose input side is connected to a corresponding wind turbine in the wind power system, and whose output side is connected to the input side of the transformer.

[0027] The power conversion module of the battery system comprises at least one bidirectional inverter, whose DC side is connected to a corresponding battery cluster in the battery system, and whose AC side is connected to the input side of the transformer.

[0028] The high and low voltage fault ride-through control method of the new energy power station provided in the present application, in the structure that at least two power conversion modules of new energy systems are arranged at the front stage of the transformer in the new energy power station, first determines the total reactive current required by the input side of the transformer during high and low voltage fault ride-through of the new energy power station according to the rated current of the input side of the transformer; then determines the reactive current distribution amount of each power conversion module when the total reactive current requirement can be met and the sum of the active currents output by each power conversion module is maximum, so as to adjust the control strategy of the new energy power station during high and low voltage fault ride-through; finally, sends each reactive current distribution amount to the corresponding power conversion module, so that each power conversion module operates in the state of outputting the corresponding reactive current distribution amount during high and low voltage fault ride-through; thereby, sufficient reactive current is ensured, voltage support is provided for the power grid, and at the same time, the active current is maximized to maintain the stability of the frequency as much as possible. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings to be used in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of the provided drawings.

[0030] Figure 1 A structural schematic diagram of a new energy power station provided by an embodiment of the present application is provided.

[0031] Figure 2 A flowchart of a high and low voltage fault ride-through control method of a new energy power station provided by an embodiment of the present application is provided.

[0032] Figure 3 A specific flowchart of a high and low voltage fault ride-through control method of a new energy power station provided by an embodiment of the present application is provided. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0034] In the present application, the term “comprising”, “containing” or any other variant thereof is intended to cover the non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or further includes the elements inherent to such process, method, article or equipment. Without more limitations, the element defined by the sentence “including a…” does not exclude the presence of another same element in the process, method, article or equipment including the element.

[0035] The present application provides a high and low voltage fault ride-through control method of a new energy power station, so as to ensure sufficient reactive current and maximize the provision of active current when the new energy power station experiences high and low voltage fault ride-through.

[0036] In the new energy power station, at least two power conversion modules of new energy systems are arranged in front of the transformer, where the new energy systems can be photovoltaic systems, wind power systems or battery systems. The new energy power station can include at least two of them, or all three of them, thereby forming a wind-solar-storage power station (for example, a wind-solar-battery power station). Figure 1(As shown in the diagram). Each power conversion module includes at least one converter matched to its connected renewable energy system. Each converter is located between the corresponding power source in the connected renewable energy system and the input side of the transformer. Specifically, the power source in the photovoltaic system is a photovoltaic string, and the converter connected to it is a photovoltaic inverter; the power source in the wind power system is a wind turbine, and the converter connected to it is a wind power converter; the power source in the battery system is a battery cluster, and the converter connected to it is a bidirectional inverter. The specific settings of each power source and its converter, as well as other structural settings of the renewable energy power station, can be found in the prior art and will not be described in detail here.

[0037] The high and low voltage fault ride-through control method of this new energy power station, such as Figure 2 As shown, it includes:

[0038] S101. Based on the rated current on the input side of the transformer, determine the total reactive current required on the input side of the transformer for the new energy power station during high and low voltage fault ride-through.

[0039] When high or low voltage faults occur, the voltage on the transformer input side will change accordingly. Different voltage ratio changes will require different reactive current ratios on the transformer input side. This reactive current ratio refers to the ratio between the total reactive current provided by all converters on the transformer input side and the rated current on the transformer input side. Therefore, when a high or low voltage fault occurs, the total reactive current required on the transformer input side can be determined based on the rated current on the transformer input side and the fault voltage at that time.

[0040] In practical applications, the rated current on the transformer input side can be calculated and the total reactive current can be determined by using the change in the voltage ratio on the transformer input side during high and low voltage fault ride-through, and the preset ratio between the dynamic reactive current ratio on the transformer input side and the voltage ratio change.

[0041] At this point, the specific formula used to calculate the total reactive current under different fault voltages on the transformer input side can be:

[0042]

[0043] In the formula:

[0044] I T It is the sum of the effective values ​​of the dynamic reactive current output by the upstream converter on the input side of the transformer, that is, the total reactive current mentioned above. When its value is positive, it represents the output of inductive reactive power by the upstream converter, and when its value is negative, it represents the output of capacitive reactive power by the upstream converter.

[0045] I N This is the rated current on the input side of the transformer.

[0046] K1, K2 are preset proportion values between dynamic reactive current ratio and voltage ratio change of transformer input side, and the values of K1 and K2 can be set in advance.

[0047] U T is the ratio between actual fault voltage and rated voltage U N of transformer input side under high and low voltage fault condition, and is recorded as actual ratio.

[0048] 0.9 is low voltage fault ride-through ratio, and 1.1 is high voltage fault ride-through ratio, both of which are preset ratios, and are used to subtract actual ratio under different voltage fault conditions to obtain voltage ratio change under current fault. In actual application, low voltage fault ride-through ratio and high voltage fault ride-through ratio for distinguishing different fault conditions can also take other values, and 0.9 and 1.1 in the above formula are only an example and are not limited to this.

[0049] That is, when actual ratio U T is less than low voltage fault ride-through ratio (such as 0.9 in the above formula), the preset ratio is low voltage fault ride-through ratio, and the preset proportion value is first proportion value K1; and when actual ratio U T is greater than high voltage fault ride-through ratio (such as 1.1 in the above formula), the preset ratio is high voltage fault ride-through ratio, and the preset proportion value is second proportion value K2.

[0050] It should be noted that multiple different preset fault voltages can be selected here, such as transformer input side fault voltages caused by common high and low voltage faults in actual application, and then divided by rated voltage U N to calculate corresponding actual ratio U T , and then combined with preset proportion value K1 or K2 set in advance and known rated current IN of transformer input side, each total reactive current I T of transformer input side under different fault voltages can be calculated, so as to be applied in subsequent steps according to actual fault voltage of transformer input side under high and low voltage fault ride-through to select corresponding total reactive current I T .

[0051] Alternatively, rated voltage and rated current of transformer input side and above preset proportion values K1 and K2 can also be brought into the above formula, and corresponding total reactive current calculation formula can be obtained by taking fault voltage of transformer input side under high and low voltage fault ride-through as independent variable, so as to be brought into actual fault voltage of transformer input side under high and low voltage fault ride-through in subsequent steps to obtain real-time required total reactive current I T .

[0052] In practical applications, any of the above implementation manners can be adopted according to actual conditions, and both are within the protection scope of the present application.

[0053] S102, according to the current output state of each power conversion module, determining the reactive current distribution amount of each power conversion module when the sum of the active currents output by each power conversion module is maximum and the demand of the total reactive current can be met.

[0054] The current output state of each power conversion module mainly includes the active current and voltage currently output by the power conversion module, and the active power currently output by the power conversion module can be calculated according to the active current and voltage.

[0055] Suppose that a high-low voltage fault will occur next moment, the reactive current output by each power conversion module needs to meet the total reactive current I T calculated in step S101, and at this moment, the current capacity of each power conversion module, that is, the active current that can be output by each power conversion module, will not exceed the quotient of the active power currently output by the power conversion module divided by the fault voltage, that is, each power conversion module has an upper limit of the active current that can be output in the current state.

[0056] Since the output capacity of each power conversion module in the current state is limited, the more reactive current output by the power conversion module, the less active current output, and vice versa. Therefore, for the power conversion module with a lower upper limit of the active current, the power conversion module can output more reactive current, thereby reducing the share of other power conversion modules for outputting reactive current, and enabling these power conversion modules to output more active current. Figure 1 As shown in the new energy power station including a photovoltaic system, a wind power system and a battery system, when the wind speed is high and the irradiance is low, the photovoltaic system can be mainly used to provide transient reactive power support, and the wind power system and the battery system output more active current; when the wind speed is low and the irradiance is high, the wind power system is mainly used to provide transient reactive power support, and the photovoltaic system and the battery system output more active current.

[0057] In practical applications, step S102 can be combined with the upper limit of the active current that can be output by each power conversion module in the current state to solve the maximum value of the sum of the active currents that can be output by each power conversion module under the condition that the reactive current output by each power conversion module meets the corresponding total reactive current I T . At this moment, the demand of the total reactive current I T can be met, and the active current can be maximized.

[0058] S103, sending the reactive current distribution amount of each power conversion module to the corresponding power conversion module, so that each power conversion module operates in the state of outputting the corresponding reactive current distribution amount during high-low voltage fault ride through.

[0059] After the reactive current allocation is sent to the corresponding power conversion module, the reactive current allocation will be used as the reactive current output command value in the corresponding control strategy of the corresponding power conversion module when dealing with high and low voltage faults. If a high or low voltage fault occurs, each power conversion module will operate according to the corresponding control strategy, thereby maximizing the output of active current while ensuring that each module outputs the reactive current it is allocated, so as to maximize the active current of the new energy power plant during high and low voltage fault ride-through.

[0060] The high and low voltage fault ride-through control method for the new energy power station provided in this embodiment can adjust the control strategy of the new energy power station during high and low voltage fault ride-through according to the current output status of each power conversion module through the above process, thereby ensuring sufficient reactive current to support the voltage of the power grid, and maximizing the supply of active current to maintain frequency stability as much as possible.

[0061] Based on the previous embodiment, this embodiment provides a specific implementation of step S102 in the high and low voltage fault ride-through control method, which includes... Figure 3 As shown:

[0062] S201. Collect the current active current output by each power conversion module and the current voltage on the input side of the transformer.

[0063] by Figure 1 Taking the example of a new energy power station that includes a photovoltaic system, a wind power system, and a battery system, step S201 will collect the current active current I output from the three power conversion modules respectively. d1 I d2 I d3 And, the current voltage U on the input side of the transformer.

[0064] In practical applications, step S201 can be executed in real time or periodically at a certain interval. The faster the execution frequency, the closer the final reactive current distribution will be to the actual situation and the more accurate it will be. The specific execution cycle can be determined according to the specific application environment, and all of them are within the protection scope of this application.

[0065] S202. Determine the current active power of each power conversion module.

[0066] Since each power conversion module is connected in parallel to the input side of the transformer, the voltage on the output side of each power conversion module, namely the AC side of the photovoltaic inverter, the output side of the wind power converter, and the AC side of the bidirectional inverter, is also the current voltage U on the input side of the transformer.

[0067] At this time, the current active power of each power conversion module is as follows: Id1 *U, I d2 *U, and I d3 *U.

[0068] S203, as a boundary condition, determine the corresponding reactive current distribution amount of each power conversion module when the active power output is maximum.

[0069] The boundary condition in step S203 mainly includes:

[0070] (1) The sum of each reactive current distribution amount I T1 , I T2 , I T3 is greater than or equal to the total reactive current I T .

[0071] (2) Each reactive current distribution amount I T1 , I T2 , I T3 is greater than or equal to zero.

[0072] (3) The active power that each power conversion module can output under the corresponding reactive current distribution amount I T1 , I T2 , I T3 is less than or equal to the corresponding current active power during high-low voltage fault ride-through. Specifically:

[0073] During high-low voltage fault ride-through, the active current that each power conversion module can output under the corresponding reactive current distribution amount I T1 , I T2 , I T3 is respectively:

[0074]

[0075] Where I N1 , I N2 , I N3 are the rated currents of the output sides of each power conversion module.

[0076] At this time, the active current that each power conversion module can output under the corresponding reactive current distribution amount I T1 , I T2 , I T3 is respectively:

[0077] and

[0078] wherein, U N is the rated voltage of the transformer input side, U T is the actual ratio between the actual fault voltage of the transformer input side and the rated voltage U N under high-low voltage fault condition.

[0079] the current active power of each power conversion module, respectively, is: I d1 *U, I d2 *U, and I d3 *U.

[0080] Therefore, according to the above boundary conditions, the following formulas can be listed:

[0081]

[0082] Solving

[0083] Through the above process, the maximum active current of the transformer input side under different fault voltages and the corresponding active and reactive current distribution amounts I T1 , I T2 , and I T3 of each power conversion module can be solved. Then, the calculated active current of the transformer input side and the corresponding reactive current distribution amounts I T , I T2 , and I T3 of each power conversion module can be sent to each power conversion module.

[0084] It is worth noting that in actual application, if the total reactive current I T1 obtained in step S101 is in the form of a data table under different preset fault voltages and participates in the subsequent steps, then the reactive current distribution amounts I T2 , I T3 here can be further brought into other data to present as: under different preset fault voltages, the corresponding reactive current distribution values during high-low voltage fault ride-through. If the total reactive current I T obtained in step S101 is a total reactive current calculation formula with the fault voltage during high-low voltage fault ride-through as the independent variable, then the reactive current distribution amounts here will also be another reactive current distribution value calculation formula with the fault voltage during high-low voltage fault ride-through as the independent variable after further bringing in other data. It can be determined according to the specific application environment, which is within the protection scope of the present application.

[0085] Since wind power and photovoltaic power have certain complementarity in energy and support each other in power, and Figure 1As shown in the structure, the wind, light and storage power conversion modules are electrically incorporated into the transformer in the form of low-voltage side AC coupling. In this embodiment, by collecting the operation information of the wind, light and storage power conversion modules, the control strategy of the wind, light and storage in high and low voltage fault is continuously adjusted, the active current is maximized while the sufficient reactive current is ensured. When a fault occurs, the voltage support is provided to the power grid while the frequency stability is maintained as much as possible.

[0086] In practical application, as long as at least two of the photovoltaic system, the wind power system and the battery system are included in the new energy power station, complementary output in energy can be realized, and the specific process of the implementation step S102 can be reduced by reducing the parameters of one power conversion module on the basis of the above principle, which will not be described here. However, it is within the protection scope of the present application.

[0087] Another embodiment of the present application also provides a new energy power station, which comprises a controller 40, a transformer (such as a box transformer shown in the figure) 30, and at least two new energy systems 10 and corresponding power conversion modules 20 thereof. Figure 1

[0088] The transformer 30 can be a box transformer, such as the box transformer shown in the figure.

[0089] Each new energy system 10 is connected in parallel to the input side of the transformer 30 through its own power conversion module 20, and the output side of the transformer 30 is connected to the power grid through a booster station.

[0090] The controller 40 is in communication connection with the transformer 30 and each power conversion module 20, and is used for executing the high and low voltage fault ride-through control method of the new energy power station as described in any of the above embodiments.

[0091] The specific process and principle of the high and low voltage fault ride-through control method can be referred to the above embodiments, which will not be described here.

[0092] The new energy power station can comprehensively consider the real-time operation state of each power conversion module 20 of the wind, light and storage, continuously adjust the control strategy thereof in high and low voltage fault, and maximize the provision of active current while ensuring sufficient reactive current.

[0093] In practical application, the new energy system 10 can be a photovoltaic system, a wind power system or a battery system. Figure 1 In the embodiment, each new energy system 10 is a photovoltaic system, a wind power system and a battery system. In practical application, only any two of them can be included, which is within the protection scope of the present application.

[0094] ​The power conversion module 20 of the photovoltaic system comprises at least one photovoltaic inverter, the DC side of which is connected to a corresponding photovoltaic string in the photovoltaic system, and the AC side of which is connected to the input side of the transformer 30. The photovoltaic string comprises one or at least two photovoltaic modules connected in series. The power conversion module 20 of the wind power system comprises at least one wind power converter, the input side of which is connected to a corresponding wind turbine in the wind power system, and the output side of which is connected to the input side of the transformer 30. The power conversion module 20 of the battery system comprises at least one bidirectional inverter, the DC side of which is connected to a corresponding battery cluster in the battery system, and the AC side of which is connected to the input side of the transformer 30. The battery cluster comprises one or at least two battery modules connected in series. The structure of each new energy system 10 and the corresponding power conversion module 20 can refer to various forms in the prior art, which are not limited here and are within the protection scope of the present application.

[0095] The same or similar parts among the various embodiments in the present specification can be referred to each other, and each embodiment focuses on the difference from other embodiments. In particular, for the system or system embodiment, since it is basically similar to the method embodiment, it is described more simply, and the relevant part can refer to the part of the method embodiment. The above-described system and system embodiment are only illustrative, wherein the units described as separate components can be or can not be physically separated, and the components displayed as units can be or can not be physical units, i.e., they can be located in one place or distributed on multiple network units. Part or all of the modules can be selected according to actual needs to achieve the purpose of the present embodiment. Those skilled in the art can understand and implement without creative labor.

[0096] The skilled person can further realize that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be realized in electronic hardware, computer software or a combination of both. In order to clearly illustrate the interchangeability of hardware and software, the components and steps of the examples have been described in the above description in general terms. Whether the functions are realized in hardware or software depends on the specific application and design constraints of the technical solution. The skilled person can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0097] The above description of disclosed embodiments, as well as the examples described in this specification, can be modified in various ways and can be implemented in various embodiments without departing from the spirit or essential characteristics of the application. Accordingly, the application is not to be restricted to the embodiments shown in the figures and examples, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A high and low voltage fault ride through control method for a new energy power station, characterized in that, The front stage of a transformer in a new energy power station is provided with at least two power conversion modules of new energy systems, and the high-low voltage fault ride-through control method comprises: According to the rated current of the transformer input side, determining the total reactive current required by the transformer input side when the new energy power station is in high-low voltage fault ride-through; According to the current output state of each power conversion module, determining the reactive current distribution amount of each power conversion module when the total reactive current requirement can be met and the sum of the active currents output by each power conversion module is maximum; Sending each reactive current distribution amount to the corresponding power conversion module respectively, so that each power conversion module operates in the state of outputting the corresponding reactive current distribution amount during high-low voltage fault ride-through.

2. The high and low voltage fault ride through control method of new energy power station according to claim 1, characterized in that, According to the current output state of each power conversion module, determining the reactive current distribution amount of each power conversion module when the total reactive current requirement can be met and the sum of the active currents output by each power conversion module is maximum, comprising: Collecting the current active current output by each power conversion module and the current voltage of the transformer input side; Determining the current active power of each power conversion module; As a boundary condition, determining the reactive current distribution amount of each power conversion module when the sum of the active currents output by each power conversion module is maximum, under the condition that the sum of each reactive current distribution amount is greater than or equal to the total reactive current, the active power that each power conversion module can output under the corresponding reactive current distribution amount during high-low voltage fault ride-through is less than or equal to the corresponding current active power, and each reactive current distribution amount is greater than or equal to zero. 3.The high and low voltage fault ride-through control method of new energy power station of claim 2, characterized in that, Collecting the current active current output by each power conversion module and the current voltage of the transformer input side is performed in real time or periodically.

4. The high and low voltage fault ride through control method of new energy power station according to claim 1, characterized in that, According to the rated current of the transformer input side, determining the total reactive current required by the transformer input side when the new energy power station is in high-low voltage fault ride-through, comprising: Converting the rated current of the transformer input side according to the voltage ratio change of the transformer input side during high-low voltage fault ride-through and the preset proportion value between the dynamic reactive current ratio and the voltage ratio change of the transformer input side, to determine the total reactive current.

5. The high and low voltage fault ride-through control method of new energy power station according to claim 4, characterized in that, The voltage ratio change is the difference between the preset ratio and the actual ratio, and the actual ratio is the ratio between the fault voltage and the rated voltage of the transformer input side during high-low voltage fault ride-through; When the actual ratio is less than the low voltage fault ride-through ratio, the preset ratio is the low voltage fault ride-through ratio, and the preset proportion value is a first proportion value; when the actual ratio is greater than the high voltage fault ride-through ratio, the preset ratio is the high voltage fault ride-through ratio, and the preset proportion value is a second proportion value.

6. The high and low voltage fault ride-through control method of new energy power station according to any one of claims 1 to 5, characterized in that, The reactive current distribution amount comprises: each reactive current distribution value corresponding to different preset fault voltages during high-low voltage fault ride-through.

7. The high and low voltage fault ride-through control method of new energy power station according to any one of claims 1 to 5, characterized in that, The reactive current distribution amount comprises: a calculation formula with the fault voltage during high-low voltage fault ride-through as the independent variable.

8. A new energy power station, characterized in that, Comprising: A controller, a transformer, and at least two new energy systems and their corresponding power conversion modules; wherein Each of the new energy systems is connected in parallel to the input side of the transformer through its own power conversion module; The output side of the transformer is connected to the power grid through a booster station; The controller is in communication connection with the transformer and each of the power conversion modules, and is used to execute the high and low voltage fault ride-through control method of the new energy power station according to any one of claims 1 to 7.

9. The new energy power station according to claim 8, characterized in that, The new energy system is a photovoltaic system, a wind power system, or a battery system.

10. The new energy power station according to claim 9, characterized in that, The power conversion module of the photovoltaic system comprises at least one photovoltaic inverter, whose DC side is connected to a corresponding photovoltaic string in the photovoltaic system, and whose AC side is connected to the input side of the transformer. The power conversion module of the wind power system comprises at least one wind power converter, whose input side is connected to a corresponding wind turbine in the wind power system, and whose output side is connected to the input side of the transformer. The power conversion module of the battery system comprises at least one bidirectional inverter, whose DC side is connected to a corresponding battery cluster in the battery system, and whose AC side is connected to the input side of the transformer.

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