A control method of a new energy station network construction type converter, a converter, a medium and a program product

Abstract

The application provides a control method of a new energy station network construction type converter, a converter, a medium and a program product. A converter of a first generator set in multiple generator sets of a new energy station adopts network construction type control. The control method comprises the following steps: collecting first grid connection point data of the first generator set, a voltage amplitude instruction, an active power instruction, second grid connection point data of a second generator set; determining a reactive power deviation; obtaining a virtual internal electromotive force amplitude according to the reactive power deviation, the voltage amplitude instruction and a grid connection point voltage amplitude in the first grid connection point data; determining a PWM modulation voltage instruction according to the virtual internal electromotive force amplitude and a phase of a virtual internal electromotive force; and performing spatial vector modulation on the PWM modulation voltage instruction to generate a driving signal. The control method provided by the application solves the contradiction between voltage support strength of a network construction type control unit and self grid connection small disturbance stability, and a transient circulating current problem existing in a dynamic voltage regulation process of the unit.

Description

Technical Field

[0001] This invention relates to the field of converter control technology, and in particular to a control method, converter, medium, and program product for a grid-connected converter in a new energy power station. Background Technology

[0002] Building a new power system with renewable energy as the mainstay is a major trend in achieving the ambitious goals of "carbon peaking and carbon neutrality." Grid-based control technology is key to ensuring system voltage stability as the proportion of renewable energy installed capacity increases.

[0003] Currently, based on the premise of an inductive power grid, a voltage support strategy of generating reactive power through voltage droop control is adopted for grid-connected control units in renewable energy power plants. This approach can take into account the steady-state current sharing requirements of different units when supporting voltage. However, the strength of the droop control is limited by the small-disturbance stability of the grid-connected control units. If the strength is too weak, the voltage support will be insufficient when the grid strength weakens. Furthermore, research has found that during operation in a power plant, voltage support control among multiple units can lead to circulating currents caused by transient power conduction, resulting in a discrepancy between the reactive power generated by a single unit and the voltage support strength.

[0004] If the voltage support control strategy of the grid-type control unit is changed to PI control, although its voltage support capability can be fully utilized, there are still problems in the field where transient power conduction between multiple units can cause circulating current, and the reactive power generated by a single unit is inconsistent with the voltage support strength. Although the node voltage in the field can be uniformly controlled by the field controller to avoid steady-state circulating current between multiple units, its long-distance communication is difficult to meet the requirements for suppressing transient circulating current. Summary of the Invention

[0005] This invention provides a control method, converter, medium, and program product for grid-connected converters in new energy power plants. It addresses the scenario where all converters in new energy power plants adopt grid-connected control, resolving the contradiction between the voltage support strength of grid-connected control units and their stability under small grid disturbances, as well as the transient circulating current problem existing in the dynamic voltage regulation process of the units.

[0006] According to a first aspect of the present invention, a control method for a grid-connected converter in a new energy power station is provided. The new energy power station includes multiple generator sets, each generator set including a converter. One generator set unidirectionally reads grid connection point data from another generator set, forming a ring communication topology. Each converter adopts grid-connected control. The control method includes:

[0007] Collect the first grid connection point data, voltage amplitude command and active power command of the first generator set, and collect the second grid connection point data of the second generator set read unidirectionally by the first generator set;

[0008] Determine the reactive power deviation between the reactive power data in the data from the first grid connection point and the reactive power data from the data from the second grid connection point;

[0009] Based on the reactive power deviation, voltage amplitude command, and grid connection point voltage amplitude in the first grid connection point data, the virtual internal potential amplitude is obtained after adjustment.

[0010] Based on the active power command and the active power in the data of the first grid connection point, the phase of the virtual internal potential is obtained after adjustment;

[0011] The PWM modulation voltage command is determined based on the amplitude and phase of the virtual internal potential.

[0012] The PWM modulated voltage command is space vector modulated to generate the drive signal required to control the converter.

[0013] In one possible implementation, the reactive power data in the first grid connection point data is reactive power, and determining the reactive power deviation between the reactive power data in the first grid connection point data and the reactive power data in the second grid connection point data includes:

[0014] Determine the reactive power deviation between the reactive power data of the first grid connection point and the reactive power data of the second grid connection point, and use the reactive power deviation as the reactive power deviation.

[0015] In one possible implementation, the reactive power data in the first grid connection point data is reactive current, and determining the reactive power deviation between the reactive power data in the first grid connection point data and the reactive power data in the second grid connection point data includes:

[0016] The reactive current deviation between the reactive current in the data of the first grid connection point and the reactive current in the data of the second grid connection point is determined, and the reactive current deviation is taken as the reactive current deviation.

[0017] In one possible implementation, the grid connection point data of the generator set read unidirectionally by the second generator set is the third grid connection point data of the third generator set; if the reactive power data in the first grid connection point data is reactive power, the reactive power data in the second grid connection point data is: the reactive power output by the second generator set, or the weighted sum of the reactive power output by the second generator set and the reactive power output by the third generator set.

[0018] If the reactive power data in the first grid connection point data is reactive current, then the reactive power data in the second grid connection point data is: the reactive current output by the second generator set, or the weighted sum of the reactive current output by the second generator set and the reactive current output by the third generator set. In one possible implementation, based on the reactive power deviation, voltage amplitude command, and grid connection point voltage amplitude in the first grid connection point data, a virtual internal potential amplitude is obtained after adjustment, including:

[0019] Adjusting the reactive power deviation yields an auxiliary voltage regulation command;

[0020] The auxiliary voltage regulation command and the voltage amplitude command are superimposed, and the difference between them and the grid connection point voltage amplitude in the first grid connection point data is obtained to obtain the voltage deviation control quantity.

[0021] The voltage deviation control value is adjusted to obtain the virtual internal potential amplitude.

[0022] In one possible implementation, when the reactive power deviation is equal to the reactive power deviation, it is expressed by the following formula:

[0023]

[0024]

[0025] in, To assist in voltage regulation commands, To adjust the gain for reactive power deviation, This refers to reactive power deviation. The magnitude of the virtual internal potential. This is a voltage amplitude command. The voltage amplitude at the first grid connection point. This is the transfer function of the voltage amplitude regulator.

[0026] In one possible implementation, the phase of the virtual internal potential is obtained by adjustment based on the active power command and the active power in the data from the first grid connection point, including:

[0027] Determine the active power command and the active power deviation before the active power;

[0028] The phase of the virtual internal potential is obtained by adjusting the active power deviation.

[0029] According to a second aspect of the present invention, a converter is provided. A new energy power station includes multiple generator sets, each generator set including a converter. The converter is characterized in that one generator set reads grid connection point data of another generator set in one direction to form a ring communication topology. The converter includes a controller, which is used to execute the steps of the control method for the grid-type converter of the new energy power station in the first aspect of the present invention or any possible implementation thereof.

[0030] According to a third aspect of the present invention, a readable storage medium is provided, on which computer program instructions are stored, wherein the computer program instructions are executed by a processor to perform the steps of the control method for a grid-connected converter in a new energy power station in the first aspect or any possible implementation thereof.

[0031] According to a fourth aspect of the present invention, a computer program product is provided, wherein the instructions in the computer program product, when executed by a processor of an electronic device, cause the electronic device to perform the steps of the control method for a grid-connected converter in a new energy power station in the first aspect or any possible implementation thereof.

[0032] This invention discloses a control method, converter, medium, and program product for a grid-connected converter in a new energy power station. The new energy power station includes multiple generator sets, each with a grid-connected converter. One generator set unidirectionally reads grid connection point data from another generator set, forming a ring communication topology. For scenarios where all generator sets in a new energy power station employ grid-connected control, the method collects the first grid connection point data, voltage amplitude command, and active power command from the first generator set, and collects the second grid connection point data from the second generator set through unidirectional communication with the first generator set; the first grid connection point is then determined. The reactive power deviation between the reactive power data in the data and the reactive power data in the second grid connection point data is analyzed. Based on the reactive power deviation, voltage amplitude command, and the grid connection point voltage amplitude in the first grid connection point data, a virtual internal potential amplitude is obtained through adjustment. Based on the active power command and the active power in the first grid connection point data, the phase of the virtual internal potential is obtained through adjustment. Based on the virtual internal potential amplitude and the phase of the virtual internal potential output by the active power loop, a PWM modulation voltage command is determined. The PWM modulation voltage command is then subjected to space vector modulation to generate the drive signal required to control the converter. This solves the contradiction between the voltage support capacity of the grid-connected units and their own grid connection stability under small disturbances. It not only fully utilizes the voltage support capacity of the grid-connected units in the power station but also avoids the generation of transient circulating currents between units while ensuring the stable grid-connected operation of the grid-connected control unit group. Moreover, the control method of this invention is simple to implement, requiring only one-way communication between units to achieve effective voltage support for multiple nodes in the power station, making it highly practical for engineering applications. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0034] Figure 1 A schematic diagram of the control system of a grid-type converter for a new energy power station is provided in an embodiment of the present invention;

[0035] Figure 2 A schematic diagram of the control system of another grid-type converter for new energy power plants provided in an embodiment of the present invention;

[0036] Figure 3 A flowchart illustrating a control method for a grid-connected converter in a new energy power station, provided as an embodiment of the present invention;

[0037] Figure 4 This is a schematic diagram of the control structure of a grid-type converter for new energy power plants provided in an embodiment of the present invention;

[0038] Figure 5 This invention provides a schematic diagram of the principle of generating virtual internal potential amplitude in a grid-type control unit in a new energy power station;

[0039] Figure 6 Simulation diagram of the control effect of traditional droop control for grid-type control units in new energy power plants;

[0040] Figure 7 Simulation diagram of the control effect of grid-type control units in new energy power plants when the method of this invention is not used;

[0041] Figure 8 Simulation diagram of the control effect when the control method provided by this invention is used for grid-type control units in new energy power plants. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] Converter: An electrical device that changes the voltage, frequency, number of phases, and other electrical quantities or characteristics of a power supply system. It includes rectifiers (AC to DC), inverters (DC to AC), AC converters, and DC converters. New energy power generation is connected to the grid via converters.

[0044] The method provided in this invention is applied to the converters of generator units in new energy power plants, such as wind power converters in wind power plants and photovoltaic converters in photovoltaic power plants.

[0045] Example 1

[0046] This invention provides a control system for a grid-type converter in a new energy power station, including an equivalent power grid and a power feeder side, as well as the external circuit and control loop of the converter in the new energy power station. The equivalent power grid and the power feeder side are connected through a DC bus, and the power feeder side consists of energy storage equipment, photovoltaic generators and / or wind turbines.

[0047] A new energy power plant may include multiple generator sets, each generator set including a converter, and the converters of these generator sets all adopt grid-type control.

[0048] Control system such as Figure 1 As shown or Figure 2 As shown, the converter of one generator set reads the grid connection point data (e.g., reactive power Q) of another generator set in a single direction. Importi This forms a ring communication topology. To shorten the communication distance, one generator set reads the grid connection point data of an adjacent generator set. According to... Figure 1 The reactive power Q received by unit 1 from the adjacent unit Import1 =Q2, the reactive power Q received by unit 2 from the adjacent unit. Import2 =Q3, ..., The reactive power Q received by unit n from adjacent units. Importn =Q1.

[0049] Among them, u g1 : The grid connection point voltage of Unit 1 in the power station;

[0050] I g1 : Grid-side current of Unit 1 in the power station;

[0051] Z g Impedance between the station's common connection point and the remote power grid;

[0052] Z l1 The impedance between Unit 1 and the point of common coupling in the station;

[0053] Z f1 The impedance of the filter inductor of Unit 1 in the power station;

[0054] C f1 : AC filter capacitor for Unit 1 in the power station;

[0055] u dc1 DC voltage of Unit 1 in the power station;

[0056] P set1 : Active power command for unit 1 in the power station;

[0057] U set : Voltage amplitude command for generating units in the power station, defaults to rated voltage;

[0058] : The vector of the voltage command transmitted by Unit 1 in the station on the αβ axis;

[0059] : PWM modulation voltage command for unit 1 in the station.

[0060] The converter of unit 1 with grid-type control adopts grid-type control, and the control structure is as follows: Figure 1 or Figure 2 As shown, it includes a network-type control module and a pulse width modulation (PWM) unit.

[0061] The grid-type control module is based on the grid-side current i g1 Second grid voltage u g1 Active power command P set1 Voltage amplitude command U set Generate PWM modulation voltage command The PWM modulation unit is based on DC voltage u dc1 PWM modulation voltage command Modulation is performed to output the drive signals of each switching transistor required for converter control, so as to realize the control of unit 1.

[0062] Based on the aforementioned grid-connected converter control system for new energy power plants, this embodiment of the invention provides a grid-connected converter control method for new energy power plants. The converter of the first generator unit among multiple generator units adopts grid-connected control. The first generator unit is any generator unit in the new energy power plant, denoted as unit i. The control structure of unit i is as follows: Figure 3 As shown, the grid-type control module includes a power calculation unit, an active power synchronization control unit, a voltage amplitude control unit, and a reference voltage command generation unit.

[0063] in:

[0064] : The grid connection point voltage of unit i in the power station;

[0065] : Grid-side current of unit i in the power station;

[0066] Impedance between the station's common connection point and the remote power grid;

[0067] The impedance between unit i and the point of common coupling in the station;

[0068] The impedance of the filter inductor of unit i in the power station;

[0069] : AC filter capacitor for unit i in the power station;

[0070] DC voltage of unit i in the power station;

[0071] : DC-side capacitor of unit i in the power station;

[0072] : Active power command for unit i in the power station;

[0073] U ref : Voltage amplitude command for generating units in the power station, defaults to rated voltage;

[0074] , Active and reactive power of the grid unit i in the power station;

[0075] The reactive power received by unit i in the power station's grid from neighboring units;

[0076] The virtual internal potential amplitude of unit i in the power station;

[0077] The phase of the virtual internal potential of unit i in the station;

[0078] : PWM modulation voltage command for grid-connected unit i in the power station.

[0079] The control method applied to the converter of the first generator set is as follows: Figure 4 As shown, it includes the following steps:

[0080] S110 collects the first grid connection point data, voltage amplitude command, and active power command of the first generator set, and collects the second grid connection point data of the second generator set read unidirectionally by the first generator set.

[0081] The first generator set is any generator set in the new energy power station, and the first generator set reads the grid connection point data of the second generator set in one direction.

[0082] The first grid connection point data represents the data of the grid connection point of the first generator set, including at least the reactive power data of the first generator set's grid connection point; the second grid connection point data represents the data of the grid connection point of the second generator set, including at least the reactive power data of the second generator set's grid connection point. The converter of the first generator set acquires the reactive power data of the first generator set's grid connection point and the reactive power data of the second generator set's grid connection point.

[0083] S120, determine the reactive power deviation between the reactive power data in the first grid connection point data and the reactive power data in the second grid connection point data.

[0084] In one embodiment, the reactive power data in the first grid connection point data is reactive power, and the reactive power deviation between the reactive power data in the second grid connection point data and the reactive power data in the third grid connection point data is determined, and the reactive power deviation is taken as the second reactive power deviation.

[0085] The first grid connection point data also includes the grid-side current i gi and grid voltage u gi The reactive power data in both the first and second grid connection points is reactive power, based on the grid-side current i of the first generator unit. gi Grid voltage u gi Perform power calculations to obtain the reactive power Q. i The reactive power in the data from the second grid connection point is Q. Importi Calculate Q i and Q Importi The difference is used to obtain the reactive power deviation. The reactive power deviation As reactive power deviation.

[0086] In another embodiment, the reactive data in the first grid connection point data is reactive current, and the reactive current deviation between the reactive current in the first grid connection point data and the reactive current in the second grid connection point data is determined, and the reactive current deviation is taken as the reactive current deviation.

[0087] The first grid connection point data also includes the grid-side current i gi The reactive power data in both the first and second grid connection points are reactive current, which affects the grid-side current i of the first generator unit. gi Perform coordinate transformation to obtain the reactive current i qi The reactive current in the data from the second grid connection point is i qImporti Calculate i qi and i qImporti The difference is used to obtain the reactive current deviation. The reactive current deviation As reactive power deviation.

[0088] S130, based on the reactive power deviation, voltage amplitude command and the grid connection point voltage amplitude in the first grid connection point data, obtains the virtual internal potential amplitude through adjustment.

[0089] First, the reactive power deviation is adjusted to obtain the auxiliary voltage regulation command; then, the auxiliary voltage regulation command is superimposed with the voltage amplitude command, and the difference is calculated with the grid connection point voltage amplitude in the first grid connection point data to obtain the voltage deviation control quantity; finally, the voltage deviation control quantity is adjusted to obtain the virtual internal potential amplitude.

[0090] When the reactive power deviation is the same as the reactive power deviation, the structure of the voltage amplitude control unit is as follows: Figure 5 As shown, the reactive power deviation is adjusted to obtain the auxiliary voltage regulation command. Then, the auxiliary voltage regulation command will be executed. With voltage amplitude command After superposition, it is compared with the voltage amplitude of the first grid connection point in the data of the first grid connection point. By taking the difference, the voltage deviation control quantity is obtained. Voltage deviation control quantity Adjustments are made to obtain the virtual internal potential amplitude. .

[0091] The adjustment process can be represented by the following formula:

[0092]

[0093]

[0094] In the formula, This refers to reactive power deviation. Gain adjustment for reactive power deviation The transfer function is the voltage amplitude regulator, which is used in this invention as a PI regulator or a quasi-PI regulator.

[0095] S140, based on the active power command and the active power in the data of the first grid connection point, adjusts to obtain the phase of the virtual internal potential.

[0096] The first grid connection point data also includes the grid-side current i gi and grid voltage u gi The power calculation unit calculates the power based on the grid-side current i. gi and grid voltage u gi Calculate active power P i The active power synchronization control unit includes an active power loop, which determines the active power command P. refi Second active power P i Active power deviation between Regarding active power deviation Adjustment is performed to obtain the phase of the virtual internal potential. It can be expressed by the following formula:

[0097]

[0098] In the formula, J i For virtual rotational inertia, D i The damping coefficient is... This is the rated frequency of the power grid.

[0099] S150 determines the PWM modulation voltage command based on the amplitude and phase of the virtual internal potential.

[0100] The reference voltage command generation unit generates a PWM modulation voltage command based on the amplitude and phase of the virtual internal potential, which can be expressed by the following formula:

[0101]

[0102] In the formula, This is a PWM modulation voltage command.

[0103] S160 performs space vector modulation on the PWM modulated voltage command to generate the drive signal required to control the converter.

[0104] Based on DC voltage u dci For PWM modulation voltage commands Space vector modulation is performed to generate the PWM drive signal required to control the converter, thereby controlling the first generator set.

[0105] Figure 6 , Figure 7 and Figure 8 The figures represent simulations of the control effects when three grid-controlled generating units (Unit 1, Unit 2, and Unit 3) within a new energy power station are connected to the grid, gradually load and maintain the load for a period of time starting from the 2nd second, and then gradually remove the load. Figure 6 This is a simulation diagram showing the control effect of the traditional droop voltage regulation control method. Figure 7 This is a simulation diagram showing the effect when the method of this invention does not use the reactive power information of adjacent units for auxiliary regulation, but uses voltage amplitude control for other parts of the strategy. Figure 8 The diagram shows the simulation effect of the control method provided in the embodiment of the present invention.

[0106] from Figure 6 As can be seen, when using the traditional droop control voltage support scheme, the unit loading causes a significant drop in its grid connection point voltage and the station's point of common coupling voltage. During the voltage drop, reactive power mutual conduction between units (the reactive power has inconsistent signs; grid-connected units should be generating positive reactive power during the voltage drop) causes reactive power circulating current problems; from... Figure 7 As can be seen, when the method of this invention does not use the reactive power information of adjacent units for auxiliary regulation but uses voltage amplitude control for other parts of the strategy, the magnitude of the voltage drop at the grid connection point and the common coupling point of the station caused by the unit loading is greatly suppressed. However, the problem of reactive power circulation caused by reactive power mutual conduction between units during the voltage drop (inconsistent signs of reactive power, and the grid-connected units should generate positive reactive power during the voltage drop) still exists; and from Figure 8 As can be seen, by adopting the method of the present invention, not only is the magnitude of the voltage drop at the grid connection point and the voltage drop at the common coupling point of the station caused by the unit loading greatly suppressed, but also the reactive power response of all units tends to be consistent during the voltage drop process, and there is no problem of transient reactive power circulation between units.

[0107] This invention discloses a control method for a grid-connected converter in a new energy power station. The new energy power station includes multiple generator sets, each generator set including a grid-connected converter. One generator set reads grid connection point data from another generator set in a one-way manner, forming a ring communication topology. For scenarios where all generator sets in the new energy power station employ grid-connected control, the method collects the first grid connection point data, voltage amplitude command, and active power command of the first generator set, and collects the second grid connection point data of the second generator set, which communicates unidirectionally with the first generator set. The method determines the reactive power deviation between the reactive power data in the first grid connection point data and the reactive power data in the second grid connection point data. Based on the reactive power deviation, voltage amplitude command, and grid connection point voltage amplitude in the first grid connection point data, a virtual internal potential amplitude is obtained through adjustment. Based on the active power command and the active power in the first grid connection point data, the phase of the virtual internal potential is obtained through adjustment. Based on the virtual internal potential amplitude and the phase of the virtual internal potential, a PWM modulation voltage command is determined. The PWM modulation voltage command is then subjected to space vector modulation to generate the drive signal required to control the converter. This invention resolves the contradiction between the voltage support capacity of grid-connected generating units and their stability under small grid disturbances. It not only fully utilizes the voltage support capabilities of grid-connected generating units within the power station but also ensures stable grid-connected operation of the grid-controlled unit group while preventing the generation of transient circulating currents between units. Furthermore, the control method of this invention is simple to implement, requiring only one-way communication between units to effectively support the voltage of multiple nodes in the power station, making it highly practical for engineering applications.

[0108] Example 2

[0109] In one embodiment, the grid connection point data of the generator set read unidirectionally by the second generator set is the third grid connection point data of the third generator set; if the reactive power data in the first grid connection point data is reactive power, the reactive power data in the second grid connection point data is: the reactive power output by the second generator set, or the weighted sum of the reactive power output by the second generator set and the reactive power output by the third generator set.

[0110] If the reactive power data in the first grid connection point data is reactive current, then the reactive power data in the second grid connection point data is: the reactive current output by the second generator set, or the weighted sum of the reactive current output by the second generator set and the reactive current output by the third generator set. Specifically, when the reactive power data in the first grid connection point data is reactive power, the reactive power data in the second grid connection point data is the reactive power output by the second generator set, or the weighted sum of the reactive power output by the second generator set and the reactive power output by the third generator set; when the reactive power data in the first grid connection point data is reactive current, the reactive power data in the second grid connection point data is the reactive current output by the second generator set, or the weighted sum of the reactive current output by the second generator set and the reactive current output by the third generator set.

[0111] The embodiments of the present invention provide a variety of alternative reactive power data. When one reactive power data fails to be acquired, another reactive power data can be used to ensure the smooth progress of the control process and improve the reliability of system operation.

[0112] Example 3

[0113] Accordingly, this embodiment of the invention also provides a converter. The new energy power station includes multiple generator sets, each generator set including a converter. The characteristic is that one generator set reads the grid connection point data of another generator set in one direction to form a ring communication topology. The grid-type converter includes a controller, which is used to execute the steps of the grid-type control method of the converter in the new energy power station in the above embodiment of the invention.

[0114] The converter provided in this embodiment belongs to the same inventive concept as the control method for the grid-type converter of new energy power plants provided in the above embodiments of the present invention. It can execute the control method for the grid-type converter of new energy power plants provided in any of the above embodiments of the present invention, and has the corresponding functional modules and beneficial effects of the control method for the grid-type converter of new energy power plants. Technical details not described in detail in this embodiment can be found in the specific processing content of the control method for the grid-type converter of new energy power plants provided in the above embodiments of the present invention, and will not be repeated here.

[0115] Example 4

[0116] Furthermore, embodiments of the present invention may also be readable storage media storing computer program instructions, which are executed by a processor in the control methods of the grid-type converters for new energy power plants described above in various embodiments of the present invention.

[0117] Example 5

[0118] An embodiment of the present invention provides a computer program product, which includes computer program instructions. When the instructions in the computer program product are executed by a processor of an electronic device, the electronic device causes the electronic device to perform the steps in the control method of the grid-type converter for a new energy power station described above in various embodiments of the present invention.

[0119] Computer program products can be written in any combination of one or more programming languages ​​to perform the operations of the embodiments of the present invention. The programming languages ​​include object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0120] For the foregoing method embodiments, in order to simplify the description, they are all described as a series of actions. However, those skilled in the art should understand that the present invention is not limited to the described order of actions, because according to the present invention, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to the present invention.

[0121] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For apparatus embodiments, since they are basically similar to method embodiments, the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0122] The steps in the methods of the various embodiments of the present invention can be adjusted, merged, or deleted in order according to actual needs, and the technical features described in the various embodiments can be replaced or combined.

[0123] The modules and units in the various embodiments of the present invention's devices and terminals can be merged, divided, or deleted according to actual needs.

[0124] In the embodiments provided by this invention, it should be understood that the disclosed terminals, devices, and methods can be implemented in other ways. For example, the terminal embodiments described above are merely illustrative; for instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or modules may be combined or integrated into another module, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or modules, and may be electrical, mechanical, or other forms.

[0125] The modules or units described as separate components may or may not be physically separate. The components that are modules or units may or may not be physical modules or units; that is, they may be located in one place or distributed across multiple network modules or units. Some or all of the modules or units can be selected to achieve the purpose of this embodiment according to actual needs.

[0126] Furthermore, the functional modules or units in the various embodiments of the present invention can be integrated into one processing module, or each module or unit can exist physically separately, or two or more modules or units can be integrated into one module. The integrated modules or units described above can be implemented in hardware or in the form of software functional modules or units.

[0127] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0128] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software unit executed by a processor, or a combination of both. The software unit can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0129] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0130] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A control method for a grid-connected converter in a new energy power station, wherein the new energy power station includes multiple generator sets, and each generator set includes a grid-connected converter, characterized in that... One generator set reads grid connection point data from another generator set in a unidirectional manner, forming a ring communication topology. The control method includes: Collect the first grid connection point data, voltage amplitude command and active power command of the first generator set, and collect the second grid connection point data of the second generator set read unidirectionally by the first generator set; Determine the reactive power deviation between the reactive power data in the first grid connection point data and the reactive power data in the second grid connection point data; Based on the reactive power deviation, the voltage amplitude command, and the grid connection point voltage amplitude in the first grid connection point data, the virtual internal potential amplitude is obtained after adjustment. Based on the active power command and the active power in the data of the first grid connection point, the phase of the virtual internal potential is obtained after adjustment; The PWM modulation voltage command is determined based on the amplitude and phase of the virtual internal potential. The PWM modulated voltage command is space vector modulated to generate the drive signal required to control the converter.

2. The control method for the grid-type converter of a new energy power station according to claim 1, characterized in that, The reactive power data in the first grid connection point data is reactive power. Determining the reactive power deviation between the reactive power data in the first grid connection point data and the reactive power data in the second grid connection point data includes: Determine the reactive power deviation between the reactive power in the data of the first grid connection point and the reactive power in the data of the second grid connection point, and use the reactive power deviation as the reactive power deviation.

3. The control method for the grid-type converter in a new energy power station according to claim 1, characterized in that, The reactive power data in the first grid connection point data is reactive current. Determining the reactive power deviation between the reactive power data in the first grid connection point data and the reactive power data in the second grid connection point data includes: Determine the reactive current deviation between the reactive current in the data of the first grid connection point and the reactive current in the data of the second grid connection point, and use the reactive current deviation as the reactive current deviation.

4. The control method for the grid-type converter of a new energy power station according to claim 1, characterized in that, The grid connection point data of the second generator set read unidirectionally is the third grid connection point data of the third generator set. If the reactive power data in the first grid connection point data is reactive power, the reactive power data in the second grid connection point data is: the reactive power output by the second generator set, or the weighted sum of the reactive power output by the second generator set and the reactive power output by the third generator set. If the reactive data in the first grid connection point data is reactive current, the reactive data in the second grid connection point data is: the reactive current output by the second generator set, or the weighted sum of the reactive current output by the second generator set and the reactive current output by the third generator set.

5. The control method for the grid-type converter of a new energy power station according to claim 1, characterized in that, The step of adjusting the virtual internal potential amplitude based on the reactive power deviation, the voltage amplitude command, and the grid connection point voltage amplitude in the first grid connection point data includes: The reactive power deviation is adjusted to obtain an auxiliary voltage regulation command; The auxiliary voltage regulation command and the voltage amplitude command are superimposed, and the difference between them and the grid connection point voltage amplitude in the first grid connection point data is obtained to obtain the voltage deviation control amount. The voltage deviation control value is adjusted to obtain the virtual internal potential amplitude.

6. The control method for the grid-type converter of a new energy power station according to claim 5, characterized in that, When the reactive power deviation is the reactive power deviation, it is expressed by the following formula: in, For the auxiliary voltage regulation command, Gain adjustment for reactive power deviation The reactive power deviation is... The virtual internal potential amplitude, The voltage amplitude command, The voltage amplitude at the first grid connection point. This is the transfer function of the voltage amplitude regulator.

7. The control method for the grid-type converter of a new energy power station according to claim 1, characterized in that, The step of adjusting the phase of the virtual internal potential based on the active power command and the active power in the first grid connection point data includes: Determine the active power deviation between the active power command and the active power; The active power deviation is adjusted to obtain the phase of the virtual internal potential.

8. A converter, wherein the new energy power station includes multiple generator sets, each generator set including a grid-connected converter, characterized in that, One generator set reads the grid connection point data of another generator set in one direction to form a ring communication topology. The converter includes a controller, which is used to execute the steps of the control method of the grid-type converter for new energy power stations as described in any one of claims 1-7.

9. A readable storage medium, characterized in that, The readable storage medium stores computer program instructions, which are executed by a processor according to the steps of the control method for the grid-type converter of the new energy power station as described in any one of claims 1-7.

10. A computer program product, characterized in that, The computer program product includes computer program instructions. When the instructions in the computer program product are executed by the processor of an electronic device, the electronic device performs the steps of the control method for the grid-type converter of the new energy power station as described in any one of claims 1-7.

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