Virtual synchronous machine power angle limiting method, device, equipment, medium and program product

Abstract

The application provides a virtual synchronous machine power angle limiting method, device, equipment, medium and program product, wherein the method comprises: obtaining a voltage phase of a grid connection point of a target inverter; and obtaining an output voltage phase of a controlled virtual synchronous machine; determining a power angle of the controlled virtual synchronous machine according to the voltage phase of the grid connection point and the output voltage phase; determining whether the angle value of the power angle is greater than 0; if greater than 0, determining whether the angle value of the power angle exceeds a first power angle threshold range; if not exceeding, and the voltage phase of the grid connection point is a zeroed phase, setting the output frequency of the controlled virtual synchronous machine to be equal to the voltage frequency of the grid connection point of the target inverter; if not greater than 0, determining whether the angle value of the power angle exceeds a second power angle threshold range; if not exceeding, and the output voltage phase is a zeroed phase, setting the output frequency of the controlled virtual synchronous machine to be equal to the voltage frequency of the grid connection point. The application can effectively avoid synchronization instability.

Description

Technical Field

[0001] This invention relates to the field of virtual synchronous machine control technology, and in particular to a method, apparatus, equipment, medium, and program product for limiting the power angle of a virtual synchronous machine. Background Technology

[0002] Virtual synchronous machines (VSMs) possess external characteristics similar to traditional synchronous generators, providing voltage and frequency support to the power grid. They are widely used in the grid connection of new energy sources and energy storage converters. Specifically, VSMs simulate the inertia and damping of synchronous generators in terms of active power-frequency characteristics, and can achieve droop control in terms of reactive power-voltage characteristics. They can also simulate the inertia of the excitation windings of synchronous machines, providing active inertia and voltage support to the power grid.

[0003] Existing methods for controlling the power angle of virtual synchronous machines often indirectly limit the power angle by controlling the output frequency of the grid-connected inverter using the virtual synchronous machine. However, this indirect method of limiting the power angle of the virtual synchronous machine is prone to synchronization instability under conditions of large disturbances. Summary of the Invention

[0004] This invention provides a method, apparatus, device, medium, and program product for limiting the power angle of a virtual synchronizing machine, in order to solve the problem that existing indirect virtual synchronizing machine power angle limiting is prone to synchronization instability under large disturbance conditions.

[0005] To solve the above-mentioned technical problems, the present invention is implemented as follows:

[0006] In a first aspect, embodiments of the present invention provide a virtual synchro power angle limiting method, comprising:

[0007] Obtain the voltage phase of the grid connection point of the target inverter, wherein the target inverter is an inverter controlled by a virtual synchronous machine; and obtain the output voltage phase of the controlled virtual synchronous machine; determine the power angle of the controlled virtual synchronous machine based on the voltage phase of the grid connection point and the output voltage phase;

[0008] Determine whether the angle value of the power angle is greater than 0;

[0009] If it is greater than 0, determine whether the angle value of the power angle exceeds the preset first power angle threshold range; if it does not exceed the first power angle threshold range, and the voltage phase of the grid connection point is the phase after returning to zero, set the output frequency of the controlled virtual synchronous machine to be equal to the voltage frequency of the grid connection point of the target inverter;

[0010] If the value is not greater than 0, determine whether the angle value of the power angle exceeds the preset second power angle threshold range; if it does not exceed the second power angle threshold range and the output voltage phase is the phase after returning to zero, set the output frequency of the controlled virtual synchronizer to be equal to the voltage frequency of the grid connection point.

[0011] Optionally,

[0012] After determining whether the angle value of the power angle exceeds a preset first power angle threshold range, the process includes:

[0013] If the first power angle threshold range is not exceeded and the output voltage phase is the phase after returning to zero, the output frequency of the controlled virtual synchronizer itself shall be used as the output frequency of the controlled virtual synchronizer.

[0014] Optionally,

[0015] After determining whether the angle value of the power angle exceeds the preset second power angle threshold range, the process includes:

[0016] If the voltage phase at the grid connection point is zero and the second power angle threshold range is not exceeded, the output frequency of the controlled virtual synchronous machine itself shall be used as the output frequency of the controlled virtual synchronous machine.

[0017] Optionally, the method for determining that the voltage phase at the grid connection point is zero includes:

[0018] The voltage phase of the grid connection point at the current moment is obtained as the first grid connection point phase, and the voltage phase of the grid connection point at the previous moment is obtained as the second grid connection point phase;

[0019] Calculate the first difference obtained by subtracting the phase of the first grid connection point from the phase of the second grid connection point;

[0020] If the first difference is greater than 3 / 2π, the voltage phase at the grid connection point is determined to be the phase after returning to zero.

[0021] Optionally, the method for determining that the output voltage phase returns to zero includes:

[0022] The output voltage phase at the current moment is obtained as the first output phase, and the output voltage phase at the previous moment is obtained as the second output phase;

[0023] Calculate the second difference obtained by subtracting the first output phase from the second output phase;

[0024] If the second difference is greater than 3 / 2π, the output voltage phase is determined to be the phase after returning to zero.

[0025] Optionally, the first power angle threshold range M satisfies: π / 2 ≤ M < 3 / 2π;

[0026] The second power angle threshold range N satisfies: -3π / 2<N≤-π / 2.

[0027] Optionally,

[0028] The time corresponding to the voltage phase at the grid connection point is the same as the time corresponding to the output voltage phase.

[0029] In a second aspect, embodiments of the present invention provide a virtual synchronizing machine power angle limiting device, comprising:

[0030] The acquisition module is used to acquire the voltage phase of the grid connection point of the target inverter, wherein the target inverter is an inverter controlled by a virtual synchronous machine; and to acquire the output voltage phase of the controlled virtual synchronous machine; and to determine the power angle of the controlled virtual synchronous machine based on the voltage phase of the grid connection point and the output voltage phase.

[0031] The determination module is used to determine whether the angle value of the power angle is greater than 0;

[0032] The first execution module is used to determine whether the angle value of the power angle exceeds the preset first power angle threshold range if the value is greater than 0; if the value does not exceed the first power angle threshold range and the voltage phase of the grid connection point is the phase after returning to zero, the output frequency of the controlled virtual synchronous machine is set to be equal to the voltage frequency of the grid connection point of the target inverter.

[0033] The second execution module is used to determine whether the angle value of the power angle exceeds the preset second power angle threshold range if it is not greater than 0; if it does not exceed the second power angle threshold range and the output voltage phase is the phase after returning to zero, the output frequency of the controlled virtual synchronizer is set to be equal to the voltage frequency of the grid connection point.

[0034] Thirdly, embodiments of the present invention provide an electronic device, including a processor, a memory, and a program or instructions stored in the memory and executable on the processor, wherein when the program or instructions are executed by the processor, they implement the steps in the virtual synchro power angle limiting method as described in any one of the first aspects.

[0035] Fourthly, embodiments of the present invention provide a readable storage medium storing a program or instructions that, when executed by a processor, implement the steps of the virtual synchronous machine power angle limiting method as described in any one of the first aspects.

[0036] Fifthly, embodiments of the present invention provide a computer program product, including computer instructions, which, when executed by a processor, implement the steps in the virtual synchronizer power angle limiting method as described in any one of the first aspects.

[0037] In this embodiment of the invention, the voltage phase of the grid connection point of the target inverter (which is an inverter controlled by a virtual synchronous machine) is obtained; the output voltage phase of the controlled virtual synchronous machine is obtained; the power angle of the controlled virtual synchronous machine is determined based on the voltage phase of the grid connection point and the output voltage phase; it is determined whether the angle value of the power angle is greater than 0; if it is greater than 0, it is determined whether the angle value of the power angle exceeds a preset first power angle threshold range; if it does not exceed the first power angle threshold range, and the voltage phase of the grid connection point is the phase after being returned to zero, the output frequency of the controlled virtual synchronous machine is set to the same as the voltage phase of the target inverter. The voltage frequency of the grid connection point of the target inverter is equal to that of the voltage frequency of the grid connection point; if it is not greater than 0, determine whether the angle value of the power angle exceeds the preset second power angle threshold range; if it does not exceed the second power angle threshold range, and the output voltage phase is the phase after returning to zero, set the output frequency of the controlled virtual synchronous machine to be equal to the voltage frequency of the grid connection point. This embodiment of the invention controls the output frequency of the controlled virtual synchronous machine to directly limit the power angle of the virtual synchronous machine, avoiding the problem of synchronization instability that easily occurs under large disturbance conditions in the existing indirect limiting method. The embodiment of the invention can effectively avoid synchronization instability. Attached Figure Description

[0038] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0039] Figure 1 This is a flowchart illustrating the virtual synchro power angle limiting method according to an embodiment of the present invention.

[0040] Figure 2 This is a schematic diagram of a grid-connected inverter.

[0041] Figure 3 A schematic diagram illustrating the principle of determining the angle of work;

[0042] Figure 4 A schematic diagram of the control structure for applying the virtual synchronous machine power angle limiting method of this invention;

[0043] Figure 5 This is a schematic block diagram of the virtual synchronizing machine power angle limiting device according to an embodiment of the present invention;

[0044] Figure 6 This is a schematic block diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0045] 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, not all, of the embodiments of the present invention. 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.

[0046] The terms "first," "second," etc., used in this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first" and "second" are generally of the same class, without limiting the number of objects; for example, the first object can be one or more. Furthermore, "or" in this application indicates at least one of the connected objects. For example, "A or B" covers three scenarios: Scenario 1: including A but not B; Scenario 2: including B but not A; Scenario 3: including both A and B. The character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0047] In the technical solutions disclosed herein, terms such as “connection,” “coupling,” or “linking” are not limited to physical or mechanical connections, but may include electrical connections.

[0048] This invention provides a method for limiting the power angle of a virtual synchronizing machine, see [link to relevant documentation]. Figure 1 As shown, Figure 1 This is a flowchart illustrating the virtual synchronizing machine power angle limiting method according to an embodiment of the present invention, including:

[0049] Step 11: Obtain the voltage phase at the grid connection point of the target inverter, which is an inverter controlled by a virtual synchronous machine; and obtain the output voltage phase of the controlled virtual synchronous machine; determine the power angle of the controlled virtual synchronous machine based on the voltage phase at the grid connection point and the output voltage phase.

[0050] Step 12: Determine if the angle value of the work angle is greater than 0;

[0051] Step 13: If it is greater than 0, determine whether the angle value of the power angle exceeds the preset first power angle threshold range; if it does not exceed the first power angle threshold range and the voltage phase of the grid connection point is the phase after returning to zero, set the output frequency of the controlled virtual synchronous machine to be equal to the voltage frequency of the grid connection point of the target inverter.

[0052] Step 14: If it is not greater than 0, determine whether the angle value of the power angle exceeds the preset second power angle threshold range; if it does not exceed the second power angle threshold range and the output voltage phase is the phase after returning to zero, set the output frequency of the controlled virtual synchronous machine to be equal to the voltage frequency of the grid connection point.

[0053] The following explanation of step 11 is illustrated with a specific example. See [link to example]. Figure 2 As shown, Figure 2 This is a schematic diagram of a grid-connected inverter using a virtual synchronous machine. In this diagram, grid-connected inverter A corresponds to the target inverter in this embodiment of the invention. L1 and L2 are both filter inductors, C is a filter capacitor, Lg is the equivalent grid inductance, Ug is the ideal grid voltage, ig is the output current of the virtual synchronous machine, and the grid connection point is PCC. The voltage at grid connection point PCC is the grid connection point voltage Upcc. Further details can be found in the documentation. Figure 3 As shown, Figure 3 This is a schematic diagram illustrating the principle of determining the power angle, where Upcc is the grid connection point voltage, θpll is the grid connection point phase, and θ( Figure 3 (Illustrated by dashed lines) represents the output voltage phase of the controlled virtual synchronizer, U represents the output voltage of the controlled virtual synchronizer, and δ represents the power angle of the controlled virtual synchronizer. In this embodiment of the invention, the power angle of the controlled virtual synchronizer is determined based on the voltage phase at the grid connection point and the output voltage phase, i.e., θ minus θpll yields the power angle δ.

[0054] It should be noted that in practical applications, the grid connection point voltage can be obtained by using the phase-locked loop in the target inverter structure.

[0055] In this embodiment of the invention, step 12 determines whether the angle value of the power angle is greater than 0. A value greater than 0 indicates that the output voltage phase of the controlled virtual synchronous machine leads the voltage phase of the grid connection point. In this case, step 13 is executed to further determine whether the angle value of the power angle exceeds a preset first power angle threshold range. If it does not exceed the first power angle threshold range, and the voltage phase of the grid connection point is the phase after being reset to zero, the output frequency of the controlled virtual synchronous machine is set to be equal to the voltage frequency of the grid connection point of the target inverter. If the voltage phase of the grid connection point is not reset to zero, it will cause an error in determining whether the angle value of the power angle exceeds the preset first power angle threshold range, that is, the output voltage phase of the controlled virtual synchronous machine may not lead the voltage phase of the grid connection point. This embodiment of the invention uses the reset voltage phase of the grid connection point as a prerequisite alongside not exceeding the first power angle threshold range, which can ensure accurate limiting of the power angle.

[0056] In this embodiment of the invention, step 12 determines whether the angle value of the power angle is greater than 0. If it is not greater than 0, it indicates that the output voltage phase of the controlled virtual synchronizer lags behind or is equal to the voltage phase of the grid connection point. In this case, step 14 is executed to further determine whether the angle value of the power angle exceeds a preset second power angle threshold range. If it does not exceed the second power angle threshold range and the output voltage phase is the phase after returning to zero, the output frequency of the controlled virtual synchronizer is set to be equal to the voltage frequency of the grid connection point. If the output voltage phase is not returned to zero, it will cause an error in determining whether the angle value of the power angle exceeds the preset second power angle threshold range, that is, the output voltage phase of the controlled virtual synchronizer may not lag behind or be equal to the voltage phase of the grid connection point. This embodiment of the invention uses returning the output voltage phase to zero as a prerequisite alongside not exceeding the second power angle threshold range, which can ensure accurate limiting of the power angle.

[0057] In this embodiment of the invention, based on the determination result of step 12, it is determined whether the next execution step is step 13 or step 14. The logic for determining the next execution step is as follows: if the angle value of the power angle is greater than 0, it should be determined whether the angle value of the power angle exceeds a preset first power angle threshold range, where the first threshold range is the threshold range of the positive value interval. Correspondingly, if the angle value of the power angle is not greater than 0, it should be determined whether the angle value of the power angle exceeds a preset second power angle threshold range, where the second threshold range is the threshold range of the negative value interval.

[0058] In this embodiment of the invention, the first threshold range is set according to the power angle control requirements for grid-connected inverter stability. Furthermore, in step 13, if the power angle does not exceed the first power angle threshold range, it indicates that the power angle exceeds the control requirements for the power angle. The second threshold range is set according to the power angle control requirements for grid-connected inverter stability. Furthermore, in step 14, if the power angle does not exceed the second power angle threshold range, it indicates that the power angle exceeds the control requirements for the power angle.

[0059] For example, to ensure the stability of the grid-connected inverter, the power angle control requirements are as follows: the upper limit of the power angle is 90 degrees, and the lower limit of the power angle is -90 degrees, that is, the power angle should be between -90 degrees and 90 degrees. Therefore, the user can set a first power angle threshold range M satisfying: π / 2 ≤ M < 3 / 2π; the user can set a second power angle threshold range N satisfying: -3π / 2 < N ≤ -π / 2.

[0060] In this example, the power angle value is greater than 0. It is determined whether the power angle value exceeds the preset first power angle threshold range (π / 2 ≤ M < 3 / 2π). If it does not exceed the first power angle threshold range (π / 2 ≤ M < 3 / 2π), then the power angle exceeds the upper limit (90 degrees). Furthermore, the voltage phase at the grid connection point is the phase after returning to zero, and the output voltage phase of the controlled virtual synchronous machine does indeed lead the voltage phase at the grid connection point. Therefore, the step of limiting the power angle is executed, that is, setting the output frequency of the controlled virtual synchronous machine to be equal to the voltage frequency of the target inverter's grid connection point.

[0061] In this example, the angle value of the power angle is not greater than 0. It is determined whether the angle value exceeds the preset second power angle threshold range (-3π / 2 < N ≤ -π / 2). If it does not exceed the second power angle threshold range (-3π / 2 < N ≤ -π / 2), then the power angle exceeds the lower limit (-90 degrees). Furthermore, the output voltage phase is the phase after returning to zero, and the output voltage phase of the controlled virtual synchronous machine is indeed lagging behind or equal to the voltage phase at the grid connection point. Therefore, the step of limiting the power angle is performed, that is, setting the output frequency of the controlled virtual synchronous machine to be equal to the voltage frequency of the target inverter's grid connection point.

[0062] In this embodiment of the invention, the voltage phase of the grid connection point of the target inverter (which is an inverter controlled by a virtual synchronous machine) is obtained; the output voltage phase of the controlled virtual synchronous machine is obtained; the power angle of the controlled virtual synchronous machine is determined based on the voltage phase of the grid connection point and the output voltage phase; it is determined whether the angle value of the power angle is greater than 0; if it is greater than 0, it is determined whether the angle value of the power angle exceeds a preset first power angle threshold range; if it does not exceed the first power angle threshold range, and the voltage phase of the grid connection point is the phase after being returned to zero, the output frequency of the controlled virtual synchronous machine is set to the same as the voltage phase of the target inverter. The voltage frequency of the grid connection point of the target inverter is equal to that of the voltage frequency of the grid connection point; if it is not greater than 0, determine whether the angle value of the power angle exceeds the preset second power angle threshold range; if it does not exceed the second power angle threshold range, and the output voltage phase is the phase after returning to zero, set the output frequency of the controlled virtual synchronous machine to be equal to the voltage frequency of the grid connection point. This embodiment of the invention controls the output frequency of the controlled virtual synchronous machine to directly limit the power angle of the virtual synchronous machine, avoiding the problem of synchronization instability that easily occurs under large disturbance conditions in the existing indirect limiting method. The embodiment of the invention can effectively avoid synchronization instability.

[0063] In some embodiments of the present invention, optionally, determining whether the angle value of the power angle exceeds a preset first power angle threshold range, followed by:

[0064] If the first power angle threshold is not exceeded and the output voltage phase is the phase after returning to zero, the output frequency of the controlled virtual synchronous machine itself shall be used as the output frequency of the controlled virtual synchronous machine.

[0065] In this embodiment of the invention, when the angle value of the power angle is greater than 0, the angle value of the power angle does not exceed the first power angle threshold range, indicating that the power angle exceeds the control requirements of the power angle. Further, the output voltage phase of the controlled virtual synchronizer is the phase after returning to zero, indicating that the output voltage phase of the controlled virtual synchronizer does not lead the voltage phase of the grid connection point, and the step of limiting the power angle is not performed. The virtual synchronizer maintains its current output frequency, that is: the output frequency of the controlled virtual synchronizer itself is used as the output frequency of the controlled virtual synchronizer.

[0066] In some embodiments of the present invention, optionally, determining whether the angle value of the power angle exceeds a preset second power angle threshold range, followed by:

[0067] If the voltage phase at the grid connection point is zero and the second power angle threshold is not exceeded, the output frequency of the controlled virtual synchronous machine itself shall be used as the output frequency of the controlled virtual synchronous machine.

[0068] In this embodiment of the invention, when the angle value of the power angle is not greater than 0, the angle value of the power angle does not exceed the range of the second power angle threshold, indicating that the power angle exceeds the control requirements of the power angle. Further, the voltage phase at the grid connection point is the phase after returning to zero, indicating that the output voltage phase of the controlled virtual synchronous machine is not lagging behind or equal to the voltage phase at the grid connection point. Therefore, the step of limiting the power angle is not executed, and the virtual synchronous machine maintains its current output frequency; that is, the output frequency of the controlled virtual synchronous machine itself is used as the output frequency of the controlled virtual synchronous machine.

[0069] In some embodiments of the present invention, optionally, the method for determining that the voltage phase at the grid connection point is zero includes:

[0070] The voltage phase of the grid connection point at the current moment is obtained as the first grid connection point phase, and the voltage phase of the grid connection point at the previous moment is obtained as the second grid connection point phase;

[0071] Calculate the first difference between the phase of the second grid connection point and the phase of the first grid connection point;

[0072] If the first difference is greater than 3 / 2π, the voltage phase at the grid connection point is determined to be the phase after returning to zero.

[0073] The method for determining whether the voltage phase of the grid connection point is zero, as described in this embodiment of the invention, can efficiently and quickly determine whether the voltage phase of the grid connection point is zero, reducing computational requirements and improving operating efficiency.

[0074] In some embodiments of the present invention, optionally, the method for determining that the output voltage phase returns to zero includes:

[0075] The output voltage phase corresponding to the current moment is obtained as the first output phase, and the output voltage phase of the previous moment is obtained as the second output phase;

[0076] Calculate the second difference obtained by subtracting the first output phase from the second output phase;

[0077] If the second difference is greater than 3 / 2π, the output voltage phase is determined to be the phase after returning to zero.

[0078] The method for determining whether the output voltage phase of the controlled virtual synchronous machine returns to zero, as described in this embodiment of the invention, can efficiently and quickly determine whether the output voltage phase of the controlled virtual synchronous machine returns to zero, reducing computational requirements and improving operating efficiency.

[0079] In some embodiments of the present invention, optionally,

[0080] The first power angle threshold range M satisfies: π / 2≤M<3 / 2π;

[0081] The second work angle threshold range N satisfies: -3π / 2<N≤-π / 2.

[0082] In this embodiment of the invention, the specific first and second threshold ranges are set by the power angle control requirements of the grid-connected inverter stability. The power angle control requirements for grid-connected inverter stability are: an upper limit of 90 degrees and a lower limit of -90 degrees, meaning the power angle should be between -90 degrees and 90 degrees. Therefore, the first power angle threshold range M can be set to satisfy: π / 2 ≤ M < 3 / 2π; the user can set the second power angle threshold range N to satisfy: -3π / 2 < N ≤ -π / 2.

[0083] See Figure 4 As shown, Figure 4 This is a schematic diagram of the control structure for the virtual synchronous machine power angle control method according to an embodiment of the present invention. θ and θpll are input quantities, 1 / z represents the value of the input quantity at the previous moment, and θ minus θpll yields the power angle δ. Depending on whether the power angle δ is greater than 0, it enters different branches for calculation. In each branch, when the power angle δ is within the threshold range corresponding to that branch, a first signal is obtained. A rising-edge monostable multivibrator is used to determine whether the phase angle has returned to zero and obtain a single-pulse signal. The single-pulse signal is input to an RS flip-flop and generates a Q signal. The Q signal is then passed through an inverter (NOT) and ANDed with the first signal input to an AND gate to determine whether to limit the power angle. When limiting the power angle, the grid connection point frequency ωpll is used as the output frequency ωout, that is, the output frequency of the controlled virtual synchronous machine is set to be equal to the voltage frequency of the grid connection point. When not limiting the power angle, the output frequency ω of the controlled virtual synchronous machine is used as the output frequency ωout, that is, the output frequency of the controlled virtual synchronous machine itself is used as the output frequency of the controlled virtual synchronous machine.

[0084] In some embodiments of the present invention, optionally, the time corresponding to the voltage phase of the grid connection point is the same time as the time corresponding to the output voltage phase, that is, the voltage phase of the grid connection point is the instantaneous voltage phase of the grid connection point at a certain moment, and the output voltage phase of the controlled virtual synchronous machine is the instantaneous output voltage phase at the same time as the voltage phase of the grid connection point.

[0085] This invention provides a virtual synchro power angle limiting device, see [link to relevant documentation]. Figure 5 As shown, Figure 5 This is a schematic diagram of the principle of the virtual synchronizing machine power angle limiting device according to an embodiment of the present invention. The virtual synchronizing machine power angle limiting device 50 includes:

[0086] The acquisition module 51 is used to acquire the voltage phase of the grid connection point of the target inverter, wherein the target inverter is an inverter controlled by a virtual synchronous machine; and to acquire the output voltage phase of the controlled virtual synchronous machine; and to determine the power angle of the controlled virtual synchronous machine based on the voltage phase of the grid connection point and the output voltage phase.

[0087] The determining module 52 is used to determine whether the angle value of the power angle is greater than 0;

[0088] The first execution module 53 is used to determine whether the angle value of the power angle exceeds the preset first power angle threshold range if it is greater than 0; if it does not exceed the first power angle threshold range and the voltage phase of the grid connection point is the phase after returning to zero, the output frequency of the controlled virtual synchronous machine is set to be equal to the voltage frequency of the grid connection point of the target inverter.

[0089] The second execution module 54 is used to determine whether the angle value of the power angle exceeds the preset second power angle threshold range if it is not greater than 0; if it does not exceed the second power angle threshold range and the output voltage phase is the phase after returning to zero, the output frequency of the controlled virtual synchronizer is set to be equal to the voltage frequency of the grid connection point.

[0090] In some embodiments of the present invention, optionally,

[0091] The first execution module 53 is further configured to, if the first power angle threshold range is not exceeded and the output voltage phase is the phase after returning to zero, use the output frequency of the controlled virtual synchronizer itself as the output frequency of the controlled virtual synchronizer.

[0092] In some embodiments of the present invention, optionally,

[0093] The second execution module 54 is further configured to, if the range of the second power angle threshold is not exceeded and the voltage phase of the grid connection point is the phase after returning to zero, use the output frequency of the controlled virtual synchronous machine itself as the output frequency of the controlled virtual synchronous machine.

[0094] Optionally, in some embodiments of the present invention, it further includes:

[0095] The grid connection point voltage phase zero determination module is used to obtain the voltage phase of the grid connection point at the current moment as the first grid connection point phase, and to obtain the voltage phase of the grid connection point at the previous moment as the second grid connection point phase.

[0096] The grid connection point voltage phase zero determination module is also used to calculate the first difference obtained by subtracting the first grid connection point phase from the second grid connection point phase;

[0097] The grid connection point voltage phase zeroing determination module is further configured to determine that the voltage phase of the grid connection point is the zeroed phase if the first difference is greater than 3 / 2π.

[0098] Optionally, in some embodiments of the present invention, it further includes:

[0099] The output voltage phase zero determination module is used to obtain the output voltage phase corresponding to the current moment as the first output phase, and to obtain the output voltage phase of the previous moment as the second output phase;

[0100] The output voltage phase zero determination module is also used to calculate the second difference obtained by subtracting the first output phase from the second output phase;

[0101] The output voltage phase zero-reset determination module is further used to determine that the output voltage phase is the zero-reset phase if the second difference is greater than 3 / 2π.

[0102] In some embodiments of the present invention, optionally,

[0103] The first power angle threshold range M satisfies: π / 2 ≤ M < 3 / 2π;

[0104] The second power angle threshold range N satisfies: -3π / 2<N≤-π / 2.

[0105] In some embodiments of the present invention, optionally,

[0106] The time corresponding to the voltage phase at the grid connection point is the same as the time corresponding to the output voltage phase.

[0107] The virtual synchronizer power angle limiting device provided in this application embodiment can achieve... Figures 1 to 4 The various processes implemented in the method embodiments achieve the same technical effect, and will not be described again here to avoid repetition.

[0108] This invention provides an electronic device 60, see [link to relevant documentation]. Figure 6 As shown, Figure 6This is a schematic diagram of the electronic device 60 according to an embodiment of the present invention, including a processor 61, a memory 62, and a program or instructions stored in the memory 62 and executable on the processor 61. When the program or instructions are executed by the processor, they implement the steps in any of the virtual synchronous machine power angle limiting methods of the present invention.

[0109] This invention provides a readable storage medium on which a program or instruction is stored. When the program or instruction is executed by a processor, it implements the various processes of the embodiments of the virtual synchronous machine power angle limiting method as described above, and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0110] The readable storage medium may include, for example, read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk. In some examples, the readable storage medium may be a non-transient readable storage medium.

[0111] This invention also provides a computer program product, including computer instructions, which, when executed by a processor, implement various processes of the embodiments of the virtual synchronous machine power angle limiting method described above, and achieve the same technical effect. To avoid repetition, these will not be described again here.

[0112] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of the present invention.

Claims

1. A method for limiting the power angle of a virtual synchronizing machine, characterized in that, include: Obtain the voltage phase at the grid connection point of the target inverter, wherein the target inverter is an inverter controlled by a virtual synchronous machine; And obtain the output voltage phase of the controlled virtual synchronizer; determine the power angle of the controlled virtual synchronizer based on the voltage phase of the grid connection point and the output voltage phase; Determine whether the angle value of the power angle is greater than 0; If it is greater than 0, determine whether the angle value of the power angle exceeds the preset first power angle threshold range; if it does not exceed the first power angle threshold range, and the voltage phase of the grid connection point is the phase after returning to zero, set the output frequency of the controlled virtual synchronous machine to be equal to the voltage frequency of the grid connection point of the target inverter; If the value is not greater than 0, determine whether the angle value of the power angle exceeds the preset second power angle threshold range; if it does not exceed the second power angle threshold range and the output voltage phase is the phase after returning to zero, set the output frequency of the controlled virtual synchronizer to be equal to the voltage frequency of the grid connection point.

2. The virtual synchro power angle limiting method according to claim 1, characterized in that, After determining whether the angle value of the power angle exceeds a preset first power angle threshold range, the process includes: If the first power angle threshold range is not exceeded and the output voltage phase is the phase after returning to zero, the output frequency of the controlled virtual synchronizer itself shall be used as the output frequency of the controlled virtual synchronizer.

3. The virtual synchro power angle limiting method according to claim 1, characterized in that, After determining whether the angle value of the power angle exceeds the preset second power angle threshold range, the process includes: If the voltage phase at the grid connection point is zero and the second power angle threshold range is not exceeded, the output frequency of the controlled virtual synchronous machine itself shall be used as the output frequency of the controlled virtual synchronous machine.

4. The virtual synchronizing machine power angle limiting method according to any one of claims 1 to 3, characterized in that, The method for determining that the voltage phase at the grid connection point is zero includes: The voltage phase of the grid connection point at the current moment is obtained as the first grid connection point phase, and the voltage phase of the grid connection point at the previous moment is obtained as the second grid connection point phase; Calculate the first difference obtained by subtracting the phase of the first grid connection point from the phase of the second grid connection point; If the first difference is greater than 3 / 2π, the voltage phase at the grid connection point is determined to be the phase after returning to zero.

5. The virtual synchro power angle limiting method according to any one of claims 1 to 3, characterized in that, The method for determining that the output voltage phase returns to zero includes: The output voltage phase at the current moment is obtained as the first output phase, and the output voltage phase at the previous moment is obtained as the second output phase; Calculate the second difference obtained by subtracting the first output phase from the second output phase; If the second difference is greater than 3 / 2π, the output voltage phase is determined to be the phase after returning to zero.

6. The virtual synchro power angle limiting method according to claim 1, characterized in that: The first power angle threshold range M satisfies: π / 2 ≤ M < 3 / 2π; The second power angle threshold range N satisfies: -3π / 2<N≤-π / 2.

7. The virtual synchro power angle limiting method according to claim 1, characterized in that, The time corresponding to the voltage phase at the grid connection point is the same as the time corresponding to the output voltage phase.

8. A virtual synchro power angle limiting device, characterized in that, include: The acquisition module is used to acquire the voltage phase of the grid connection point of the target inverter, wherein the target inverter is an inverter controlled by a virtual synchronous machine; And obtain the output voltage phase of the controlled virtual synchronizer; determine the power angle of the controlled virtual synchronizer based on the voltage phase of the grid connection point and the output voltage phase; The determination module is used to determine whether the angle value of the power angle is greater than 0; The first execution module is used to determine whether the angle value of the power angle exceeds the preset first power angle threshold range if the value is greater than 0; if the value does not exceed the first power angle threshold range and the voltage phase of the grid connection point is the phase after returning to zero, the output frequency of the controlled virtual synchronous machine is set to be equal to the voltage frequency of the grid connection point of the target inverter. The second execution module is used to determine whether the angle value of the power angle exceeds the preset second power angle threshold range if it is not greater than 0; if it does not exceed the second power angle threshold range and the output voltage phase is the phase after returning to zero, the output frequency of the controlled virtual synchronizer is set to be equal to the voltage frequency of the grid connection point.

9. An electronic device, characterized in that: It includes a processor, a memory, and a program or instructions stored in the memory and executable on the processor, wherein the program or instructions, when executed by the processor, implement the steps in the virtual synchro power angle limiting method as described in any one of claims 1 to 7.

10. A readable storage medium, characterized in that: The readable storage medium stores a program or instructions that, when executed by a processor, implement the steps in the virtual synchronous machine power angle limiting method as described in any one of claims 1 to 7.

11. A computer program product, characterized in that, It includes computer instructions that, when executed by a processor, implement the steps of the virtual synchronizer power angle limiting method as described in any one of claims 1 to 7.

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