A Fault Network Formation Operation Control Method and System under Phase Jumps of SVI Grid Voltage

Abstract

A fault grid-forming operation control method and system under SVI grid voltage phase jump. The control method includes: freezing active power integral output, equivalent internal potential phase compensation, and transient overcurrent suppression. If the difference between the grid voltage angular frequency and the self-generated angular frequency is greater than the threshold, the trigger flag is set to 1 and restored to 0 after maintaining the set time. During the period when the flag is set to 1: 1) Freeze the active power integral output to keep the self-generated angular frequency unchanged at the angular frequency of the previous moment before the fault; 2) Equivalent internal potential phase angle compensation, calculate the difference between the grid phase angle and the self-generated phase angle in real time, generate a compensation phase angle, and then generate an equivalent internal potential phase angle. During the fault ride-through period, suppress the transient overcurrent. According to the overcurrent multiple, increase the original virtual impedance by a set multiple, and / or input an additional virtual impedance and multiply it by the inductor current to obtain a compensation voltage. The reshaped instantaneous value of the internal potential is simultaneously subtracted by the compensation voltage and the grid-connected voltage and then enters the virtual impedance and current inner loop control.

Description

Technical Field

[0001] The present invention belongs to the technical field of fault ride-through of new energy inverters, and more specifically, relates to a method and system for controlling fault network operation under SVI grid voltage phase jump. Background Art

[0002] In recent years, my country's renewable energy capacity has expanded rapidly, with burgeoning developments in photovoltaics, wind power, and energy storage. Flexible and efficient power electronic inverters have become a key interface for connecting new energy devices to the grid. However, their inherent lack of inertia and damping makes them incapable of maintaining grid frequency and voltage. The integration of a high proportion of new energy devices through them poses a serious threat to grid stability. Self-synchronous voltage-source inverters (SVIs) mimic the characteristics of synchronous generators, enabling rapid synchronization at extremely low short-circuit ratios. They also incorporate damping, active power droop control, and reactive power control to support grid frequency and voltage regulation, respectively. These inverters have garnered widespread attention both within and outside the industry. However, traditional grid-connected technologies are often applied under normal grid voltage conditions and lack the ability to operate stably under grid fault conditions. Faced with large disturbances, such as grid voltage faults, SVIs can suffer from transient stability issues similar to synchronous generators.

[0003] In recent years, the industry has made significant progress in research aimed at improving grid-connected systems during grid faults, but shortcomings remain. For one thing, many studies have only considered grid voltage dips during grid faults, neglecting grid voltage phase jumps. In reality, both grid voltage amplitude and phase jumps can cause a significant voltage difference between the inverter output voltage and the grid, leading to overcurrent and power imbalance. Ignoring phase angle jumps makes many existing fault ride-through strategies difficult to apply in practical engineering. Furthermore, research on voltage source operation control during fault ride-through is incomplete. Research on control strategies for fault-connected systems has primarily focused on switching from voltage source to current source mode, directly controlling reactive and active current to achieve voltage support and current limiting. This poses challenges such as phase-locked loop instability in weak grid scenarios. Furthermore, low voltage ride-through control suffers from transient overcurrent issues, while high voltage ride-through is rarely addressed. Therefore, improving and advancing SVI voltage source operation control technology during fault ride-through is crucial for the safe and stable integration of renewable energy sources into the grid. Summary of the Invention

[0004] In order to address the deficiencies in the prior art, the present invention provides a method and system for controlling the operation of a fault network under an SVI grid voltage phase jump. This method and system can ensure that the SVI still operates smoothly in a voltage source mode when the grid voltage amplitude and phase angle jump, and effectively suppress transient overcurrent spikes, thereby improving the grid compatibility and absorption level of new energy generator sets.

[0005] The present invention adopts the following technical solutions.

[0006] A first aspect of the present invention provides a fault grid-forming operation control method under SVI grid voltage phase jump, including the following steps:

[0007] Detect the deviation between the self-generated angular frequency and the grid angular frequency. If the deviation exceeds the threshold, within the set time maintain the angular frequency at the previous moment before the fault unchanged and detect the deviation between the self-generated phase angle and the grid phase angle. If the deviation exceeds the threshold, compensate the phase of the equivalent internal potential; After

[0008] time adjust the active power command and reshape the internal potential during low voltage ride-through or high voltage ride-through according to the grid connection point voltage;

[0009] During the entire fault ride-through period, detect whether overcurrent occurs. If the amplitude of the grid-connected phase current reaches a set multiple of the rated current, perform transient overcurrent suppression control by adjusting the virtual impedance.

[0010] Preferably, set a first flag to represent whether the deviation between the self-generated angular frequency and the grid angular frequency exceeds the threshold, which is expressed by the following formula:

[0011]

[0012] In the formula:

[0013] is the first flag;

[0014] is the self-generated angular frequency;

[0015] is the grid voltage angular frequency;

[0016] is the angular frequency deviation threshold;

[0017] The first flag is set from 0 to 1, then the start time starts timing. The first flag is restored to 0 after being set from 0 to 1 and maintained for a time .

[0018] Preferably, a freezing link is configured in the active power-frequency control loop to freeze the self-generated angular frequency output by the active power droop integral link under set conditions, and take the logical NOT operation of the first flag as the output signal of the freezing link;

[0019] The output signal of the freezing link The deviation from the actual SVI active power Multiply them to obtain the SVI active power deviation considering the freezing link, which is expressed by the following formula:

[0020]

[0021] Where:

[0022] is the SVI active power deviation considering the freezing link;

[0023] is the deviation from the actual SVI active power.

[0024] Preferably, the absolute value of the deviation between the grid voltage phase and the self-generated phase is calculated in real time and compared with the threshold value, including:

[0025] If the first flag is set to 1, , that is, there is a non-negligible phase jump, and the equivalent internal potential compensation amount ; if it is detected that , no phase compensation is required;

[0026] The grid voltage phase angle and the self-generated phase angle The difference between them generates a compensation phase angle after passing through the phase angle dead zone and PI regulation, which is expressed by the following formula:

[0027]

[0028] Where:

[0029] is the compensation phase angle;

[0030] is the phase angle deviation threshold;

[0031] is the grid connection point voltage phase angle;

[0032] is the self-generated phase angle for active power control;

[0033] is the transfer function of the PI link.

[0034] Preferably, after the first flag is reset to 0, continue to implement the fault ride-through control for possible grid voltage amplitude jumps, including: taking the active power command during non-fault ride-through as the reference, adjusting the active power command during fault ride-through according to the set ratio, which is expressed by the following formula:

[0035]

[0036] Where:

[0037] It is the active power instruction when not in fault riding state. Active power instruction during fault crossing;

[0038] P eF is the grid-connected active power during the fault period, P e is the grid-connected active power before the fault;

[0039] δ is the power angle before the fault, δ F is the power angle during the fault period;

[0040] It is the active reference adjustment coefficient of high voltage ride through;

[0041] It is the active reference adjustment coefficient of low voltage ride through;

[0042] is the grid connection point voltage before the fault, is the grid connection point voltage during the fault period, is the grid voltage before the fault, is the grid voltage during the fault period, is the per-unit value of the grid-connected point voltage.

[0043] Preferably, the fault ride-through control is continued for the possible grid voltage amplitude jump, further comprising: reshaping the internal potential for maintaining the voltage source characteristics during the fault ride-through period and avoiding power imbalance, which is expressed as follows:

[0044]

[0045] Where:

[0046] is the equivalent internal potential amplitude of the SVI reshaped under fault;

[0047] is the self-generated equivalent internal potential amplitude before the fault;

[0048] is an intermediate variable;

[0049] U gN is the rated voltage of the grid;

[0050] k cis the ratio of the maximum allowable overcurrent of the inverter to the rated current;

[0051] I g is the grid-connected current;

[0052] Z eqF is the total impedance from the SVI converter port to the grid during a fault;

[0053] Z eq is the total impedance from the SVI converter port to the grid before the fault;

[0054] k F is the voltage dip depth.

[0055] Preferably, a second flag is set , indicating whether a transient overcurrent occurs; if the overcurrent multiple is greater than or equal to the multiple threshold, the second flag is set from 0 to 1; if the overcurrent multiple is less than the multiple threshold, the second flag is maintained at 0, which is expressed by the following formula:

[0056]

[0057] In the formula:

[0058] is the second flag;

[0059] is the overcurrent multiple;

[0060] is the absolute value of the grid-connected three-phase current amplitude, is the rated current;

[0061] is the multiple threshold;

[0062] When the second flag is set from 0 to 1, the transient overcurrent suppression control is started.

[0063] Preferably, the transient overcurrent suppression control includes:

[0064] using the method of adding an additional virtual impedance alone or increasing the original virtual impedance; or

[0065] using the method of combining an additional virtual impedance and increasing the original virtual impedance.

[0066] Preferably, the method of increasing the original virtual impedance includes:

[0067] According to the overcurrent multiple, increase the original virtual impedance to the set multiple, which is expressed by the following formula:

[0068]

[0069] In the formula:

[0070] is the increased virtual reactance, is a complex variable, is the increased virtual resistance, is the increased virtual impedance;

[0071] is the original virtual reactance, is the original virtual resistance, is the original virtual impedance;

[0072] is the corresponding virtual reactance increase coefficient obtained by real-time look-up table according to the overcurrent multiple;

[0073] The methods of adding additional virtual impedance include:

[0074] Real-time sample the output current of the inverter , and multiply it by the additional virtual impedance to obtain the compensation voltage . Subtract the compensation voltage and the grid-connected voltage from the reshaped instantaneous internal potential value to obtain the voltage deviation, and then perform virtual impedance and current inner-loop control to obtain the current inner-loop control reference value, which is expressed by the following formula:

[0075]

[0076] In the formula:

[0077] is the compensation voltage;

[0078] is the output current of the inverter;

[0079] is the original virtual reactance, is the original virtual resistance, is the original virtual impedance;

[0080] is the current inner-loop control reference value;

[0081] is the reshaped instantaneous internal potential value, is the compensation voltage, is the grid-connected voltage;

[0082] is the additional virtual reactance, is the additional virtual resistance, is the additional virtual impedance.

[0083] Preferably, the ways of combining the additional virtual impedance and increasing the original virtual impedance include: real-time sampling of the inverter output current , and multiplying it with the additional virtual impedance to obtain the compensation voltage , subtracting the compensation voltage from the reshaped instantaneous internal potential value , the grid-connected voltage multiplied by the second flag, and then performing virtual impedance and current inner loop control on the voltage deviation to obtain the current inner loop control reference value, which is expressed by the following formula:

[0084]

[0085] In the formula:

[0086] is the current inner loop control reference value;

[0087] is the reshaped instantaneous internal potential value, is the grid-connected voltage, is the inverter output current, is the additional virtual reactance, is the additional virtual resistance, is the additional virtual impedance, is the second flag;

[0088] is the original virtual reactance, is the original virtual resistance, is the virtual reactance increase coefficient.

[0089] The second aspect of the present invention provides a fault grid-forming operation control system under SVI grid voltage phase jump, which operates the above-mentioned fault grid-forming operation control method under SVI grid voltage phase jump, including:

[0090] A detection unit, which is used to detect the deviation between the self-generated angular frequency and the grid angular frequency. If the deviation exceeds the threshold, within the set time , maintain the self-generated angular frequency unchanged at the angular frequency of the previous moment before the fault and detect the deviation between the self-generated phase angle and the grid phase angle. If the deviation exceeds the threshold, compensate the phase of the equivalent internal potential;

[0091] An adjustment unit, which is used to adjust at time After that, according to the grid connection point voltage, during low voltage ride-through or high voltage ride-through, the active power command is adjusted and the internal electromotive force is reshaped.

[0092] A detection unit is configured to detect whether overcurrent occurs during the entire fault ride-through period. If the amplitude of the grid-connected phase current reaches a set multiple of the rated current, transient overcurrent control is performed by adjusting the virtual impedance.

[0093] Preferably, the control system further includes: an active-frequency control loop and a reactive-voltage control loop.

[0094] The flag unit outputs a first flag and a second flag. When the first flag is set to 1, it indicates that the deviation between the self-generated angular frequency and the grid angular frequency exceeds the threshold, which is used to start freezing the output control of the active droop integration link and start the equivalent internal electromotive force phase compensation control in the case of phase jump. When the second flag is set to 1, it indicates that transient overcurrent occurs, which is used to start transient overcurrent control and suppress transient overcurrent by adjusting the virtual impedance.

[0095] The active-frequency control loop includes an active droop integration link and a freezing link. The active droop integration link outputs the self-generated angular frequency , and the freezing link freezes the output of the active droop integration link based on the first flag.

[0096] Preferably, when the first flag changes from 0 to 1, it indicates that the deviation between the self-generated angular frequency and the grid angular frequency exceeds the threshold, and it returns to 0 after a holding time ;

[0097] The first flag passes through a NOT gate to generate the output signal of the freezing link.

[0098] The output signal of the freezing link is multiplied by the actual SVI active power deviation to obtain the SVI active power deviation considering the freezing link.

[0099] Preferably, the system further includes: a phase compensation link, which is configured to determine whether there is a non-negligible phase jump during the period when the first flag is set to 1. If there is a non-negligible phase jump, the difference between the grid voltage phase angle and the self-generated phase angle passes through a phase angle dead zone and PI regulation to generate a compensation phase angle .

[0100] Preferably, the system further includes: an active command proportional regulation link, which is configured to perform fault ride-through control on possible grid voltage amplitude jumps and generate active reference adjustment coefficients for non-fault ride-through, high voltage ride-through, and low voltage ride-through respectively.

[0101] Preferably, the system further includes: an internal electromotive force reshaping link, which is configured to reshape the internal electromotive force according to a set algorithm to maintain the voltage source characteristics during fault ride-through and avoid power imbalance.

[0102] Preferably, the system further includes: a transient over-current suppression control module;

[0103] When the second flag is set from 0 to 1, indicating the occurrence of a transient over-current, the transient over-current suppression control module starts the transient over-current suppression control;

[0104] The transient over-current suppression control module includes: an additional virtual impedance link and an original virtual impedance adjustment link;

[0105] The additional virtual impedance link or the original virtual impedance adjustment link is put into operation alone, or the additional virtual impedance link and the original virtual impedance adjustment link are put into operation in combination, for implementing the transient over-current suppression control.

[0106] The third aspect of the present invention provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the computer program is loaded into the processor, it implements the SVI grid voltage phase jump fault grid-forming operation control method described above.

[0107] The fourth aspect of the present invention provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the SVI grid voltage phase jump fault grid-forming operation control method described above.

[0108] Compared with the prior art, the beneficial effects of the present invention at least include:

[0109] (1) The proposed SVI control system realizes the switching control of the active frequency loop by calculating the absolute value of the difference between the grid angular frequency and the self-generated angular frequency in real time , and the absolute value of the difference between the grid phase and the self-generated phase , compensates the phase of the equivalent internal potential during the fault, and realizes that on the basis of the grid voltage amplitude jump fault, further considering the grid voltage phase jump fault, it ensures that the SVI still performs fault ride-through in the voltage source mode and provides transient support for the grid.

[0110] (2) By calculating the ratio of the phase current to the rated current in real time , and according to The deviation from the threshold value is used to switch the control of the real-time calculation and the virtual impedance during the transient process, which can effectively suppress the over-current fault during the transient process of the fault ride-through.

[0111] The present invention can ensure the stable operation of new energy generating units under grid faults, improve the grid connection friendliness of new energy generating units and the new energy consumption level. Description of the Drawings

[0112] Figure 1This is the grid - connected main circuit and control topology diagram of the SVI system of the present invention;

[0113] Figure 2 This is the diagram of freezing active power integral output and generating sw1 of the present invention;

[0114] Figure 3 This is the equivalent internal potential phase compensation diagram of the present invention;

[0115] Figure 4 This is the diagram of virtual impedance 1 and generating sw2 of the present invention;

[0116] Figure 5 This is the additional virtual impedance output diagram of the present invention;

[0117] Figure 6 This is the simulation waveform when considering phase - angle jump and low - voltage fault ride - through entering the fault in this embodiment;

[0118] Figure 7 This is the simulation waveform when considering phase - angle jump and low - voltage fault ride - through exiting the fault in this embodiment;

[0119] Figure 8 This is the simulation waveform when considering phase - angle jump and high - voltage fault ride - through entering the fault in this embodiment;

[0120] Figure 9 This is the simulation waveform when considering phase - angle jump and high - voltage fault ride - through exiting the fault in this embodiment;

[0121] Figure 10 This is the fault ride - through control flow chart. Detailed implementation manners

[0122] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. The described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the spirit of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the protection scope of the present invention.

[0123] Embodiment 1 of the present invention provides a fault - forming grid - connected operation control method under grid voltage phase jump of SVI, which at least includes: a control strategy for coping with grid phase - angle jump and a transient over - current suppression strategy. Among them, the control strategy for coping with grid phase - angle jump includes: freezing active power integral output control and equivalent internal potential phase compensation control; the transient over - current suppression strategy includes: adjusting the original virtual impedance and additional virtual impedance. Specifically, the fault - forming grid - connected operation control method under grid voltage phase jump of SVI includes the following steps:

[0124] As Figure 1As shown, the SVI main circuit topology includes: a DC power supply , an inverter, an LC filter, and a control module; among them, the DC side port of the inverter is connected to the DC power supply . The three-phase AC ports of the inverter are connected to the PCC grid connection point through the LC filter and the grid connection switch. The control module includes: an active-frequency control loop and a reactive-voltage control loop; among them, the active-frequency control loop outputs a self-generated angular frequency and a self-generated phase angle , and the reactive-voltage control loop outputs a self-generated equivalent internal potential amplitude .

[0125] It can be understood that by collecting the SVI AC grid connection point voltage and the inverter output current information, the instantaneous active power and reactive power, the grid voltage angular frequency , and the grid voltage phase are calculated.

[0126] Specifically, the reactive-voltage control loop outputs the pre-fault self-generated equivalent internal potential amplitude , which is expressed by the following formula:

[0127]

[0128] In the formula:

[0129] is the pre-fault self-generated equivalent internal potential amplitude;

[0130] is the reactive power integration coefficient, is a complex variable;

[0131] is the reactive-voltage droop coefficient;

[0132] is the reference value of the SVI output reactive power, is the average value of the SVI output reactive power;

[0133] is the grid voltage amplitude, is the grid connection point voltage amplitude.

[0134] The active-frequency control loop outputs a self-generated angular frequency and a self-generated phase angle , which is expressed by the following formula:

[0135]

[0136] In the formula:

[0137] is the phase angle self-generated for active power control;

[0138] is the self-generated angular frequency;

[0139] is a complex variable;

[0140] is the virtual rotor inertia;

[0141] is the rated angular frequency;

[0142] is the active power command during non-fault ride-through;

[0143] is the grid-connected active power before the fault;

[0144] is the active power-frequency droop coefficient.

[0145] As one of the prominent substantial features of the present invention, the control strategy for coping with the grid phase angle jump includes: detecting the deviation between the self-generated angular frequency and the grid angular frequency. If the deviation exceeds the threshold, within the set time , keep the self-generated angular frequency unchanged at the angular frequency of the previous moment before the fault and detect the deviation between the self-generated phase angle and the grid phase angle. If the deviation exceeds the threshold, compensate the phase of the equivalent internal potential.

[0146] Preferably but not restrictively, the control strategy for coping with the grid phase angle jump includes: setting a first flag , representing whether the deviation between the self-generated angular frequency and the grid angular frequency exceeds the threshold, specifically including: by calculating the absolute value of the difference between the grid voltage angular frequency and the self-generated angular frequency , that is, the voltage angular frequency deviation . When the voltage angular frequency deviation is greater than or equal to the set angular frequency deviation threshold , trigger the first flag to be set from 0 to 1 and keep it for a time and then restore it to 0; when the first flag is restored to 0, if is detected again, then trigger the first flag to be set from 0 to 1 and keep it for a time and then restore it to 0. The holding time is an adjustable parameter, which can be adjusted according to the actual engineering situation and is usually no more than dozens of milliseconds.

[0147] More specifically, as Figure 2As shown, the absolute value of the deviation between the real-time calculated grid voltage angular frequency and the self-generated angular frequency is expressed by the following formula:

[0148]

[0149] In the formula:

[0150] is the voltage angular frequency deviation, that is, the absolute value of the deviation between the grid voltage angular frequency and the self-generated angular frequency;

[0151] is the self-generated angular frequency;

[0152] is the grid voltage angular frequency.

[0153] If the detected voltage angular frequency deviation is greater than or equal to the angular frequency deviation threshold, trigger the first flag to be set from 0 to 1. Specifically, it is expressed by the following formula:

[0154]

[0155] In the formula:

[0156] is the first flag;

[0157] is the angular frequency deviation threshold.

[0158] After the first flag is set from 0 to 1 and maintained for a time , it is restored to 0. After the first flag is reset to 0, return to continue comparing the voltage angular frequency deviation with the set angular frequency deviation threshold. Assign a value to the first flag according to the above formula.

[0159] It can be understood that the active-frequency control loop includes an active droop integration link and a freezing link. The active droop integration link outputs the self-generated angular frequency , and the freezing link is used to freeze the output of the active droop integration link under set conditions. Specifically, as Figure 2 shown, during the period when the first flag is set to 1, the freezing link outputs a freezing signal, making the self-generated angular frequency output by the active droop integration link maintain the angular frequency at the moment before the fault unchanged.

[0160] Further preferably but not restrictively, take the logical NOT operation of the first flag as the output signal of the freezing link, which is expressed by the following formula:

[0161]

[0162] In the formula:

[0163] is the first flag;

[0164] is the logical NOT operation of the first flag, that is, the output signal of the freezing link.

[0165] Multiply the output signal of the freezing link by the actual SVI active power deviation to obtain the SVI active power deviation considering the freezing link, which is expressed by the following formula:

[0166]

[0167] In the formula:

[0168] is the SVI active power deviation considering the freezing link;

[0169] is the actual SVI active power deviation.

[0170] As one of the prominent substantive features of the present invention, it is improved that the active droop integral link outputs the self-generated angular frequency based on the SVI active power deviation considering the freezing link After that, during the period when the first flag is set to 1, the signal output by the freezing link is set to 0, controlling the SVI active power deviation considering the freezing link to be 0, thereby realizing that the self-generated angular frequency output by the active droop integral link maintains the angular frequency at the moment before the fault unchanged.

[0171] During the period when the first flag is set to 1, further equivalent internal potential phase compensation control is performed. Specifically, during the period when the first flag is set to 1, it is judged whether there is a non-negligible phase jump. If there is a non-negligible phase jump, the equivalent internal potential compensation amount is calculated to generate the equivalent internal potential phase angle.

[0172] More specifically, as Figure 3 shown, the grid connection point voltage is sampled in real time and the grid voltage phase angle is calculated, the self-generated phase angle generated by the active-frequency control loop is sampled in real time, the difference between the grid voltage phase angle and the self-generated phase angle passes through the phase angle dead zone and PI regulation to generate the compensation phase angle The compensation phase angle With the self-generated phase angle After summation, an equivalent internal potential phase angle is generated .

[0173] Preferably but not limited to, determining whether there is a non-negligible phase jump includes: calculating in real time the absolute value of the deviation between the grid voltage phase and the self-generated phase, and comparing it with a threshold. Specifically, if the first flag is set to 1, , that is, there is a non-negligible phase jump, and the equivalent internal potential compensation amount ; if it is detected that , no phase compensation is required.

[0174] Grid voltage phase angle and the self-generated phase angle The difference between them passes through a phase angle dead zone and PI regulation to generate a compensation phase angle ; during the period when the first flag is set to 0, the compensation phase angle has no effect, and is expressed by the following formula:

[0175]

[0176] In the formula:

[0177] is the compensation phase angle;

[0178] is the grid connection point voltage phase angle;

[0179] is the active power control self-generated phase angle;

[0180] is the phase angle deviation threshold;

[0181] is the PI link transfer function.

[0182] Compensation phase angle and the self-generated phase angle After summation, an equivalent internal potential phase angle is generated , thereby realizing phase compensation during a fault, and is expressed by the following formula:

[0183]

[0184] In the formula:

[0185] is the equivalent internal potential phase angle;

[0186] is the compensation phase angle;

[0187] is the self-generated phase angle.

[0188] That is, the first sign After setting to 1, the phase angle is generated automatically In the next The time is the self-generated angular frequency before the fault The integral output compensates the phase angle and self-generated phase angle The summation generates the equivalent internal potential phase angle , thereby achieving phase compensation during faults.

[0189] It is worth noting that in tens of milliseconds Phase compensation has been achieved for the grid voltage phase jump during the time period. After the time period, the first sign Reset to 0 and continue to implement fault ride-through control for possible grid voltage amplitude jumps, including: active power instruction during fault ride-through and reshaping of the SVI equivalent internal potential.

[0190] Based on the active power command during non-fault ride-through, the active power command during fault ride-through is adjusted according to the set ratio. Specifically, during fault ride-through, the active power reference command is expressed as follows:

[0191]

[0192] Where:

[0193] Active power instruction for non-fault ride-through; immediately when the grid-connected point voltage per unit value is detected to be 0.9pu ≤ When ≤1.1pu, continue to use the active power instruction during non-fault ride-through;

[0194] Active power instruction during fault crossing;

[0195] It is the active reference adjustment coefficient of high voltage ride through, that is, when the grid voltage per unit value is detected When ≥1.1pu, during the entire HVRT process, the active power command is: = × ;

[0196] It is the active reference adjustment coefficient for low voltage ride through; that is, when the grid connection point voltage per unit value 0 ≤ When ≤0.9pu, during the entire LVRT process, the active power command is: = × ;

[0197] is the grid connection point voltage before the fault, is the grid connection point voltage during the fault, is the grid voltage before the fault, is the grid voltage during the fault,

[0198] is the grid-connected active power during the fault, is the grid-connected active power before the fault, is the power angle before the fault, is the power angle during the fault.

[0199] During the fault ride-through, to maintain the voltage source characteristics during the fault ride-through and avoid power imbalance, internal electromotive force reshaping is carried out. The equivalently reshaped internal electromotive force is expressed by the following formula:

[0200]

[0201] Where:

[0202] is the amplitude of the reshaped SVI equivalent internal electromotive force under the fault;

[0203] is the amplitude of the self-generated equivalent internal electromotive force before the fault;

[0204] is an intermediate variable;

[0205] is the rated grid voltage;

[0206] is the grid-connected current;

[0207] [[ID=5l]]is the total impedance from the SVI converter port to the grid during the fault, Z eq is the total impedance from the SVI converter port to the grid before the fault;

[0208] is the ratio of the maximum allowable overcurrent of the inverter to the rated current;

[0209] is the voltage dip depth, taking a positive sign for low voltage ride-through and a negative sign for high voltage ride-through.

[0210] As one of the prominent substantive features of the present invention, the transient overcurrent suppression strategy includes: real-time calculation of the absolute value of the grid-connected phase current amplitude is the rated current of times. When is greater than the threshold When triggered, the second flag is set. The second flag is set from 0 to 1. During the period when it is set to 1, the transient overcurrent suppression control is started, and the transient overcurrent is suppressed by adjusting the original virtual impedance and / or the additional virtual impedance.

[0211] Preferably but not limited to, the transient overcurrent suppression strategy specifically includes:

[0212] The overcurrent multiple is calculated in real time, that is, the absolute value of the grid-connected phase current amplitude is the multiple of the rated current, which is expressed by the following formula:

[0213]

[0214] In the formula:

[0215] is the overcurrent multiple, that is, the ratio of the absolute value of the grid-connected three-phase current amplitude to the rated current;

[0216] is the absolute value of the grid-connected three-phase current amplitude, is the rated current.

[0217] Such as Figure 4 As shown, if the detected overcurrent multiple is greater than or equal to the multiple threshold, the second flag is set from 0 to 1; if the detected overcurrent multiple is less than the multiple threshold, the second flag is maintained at 0, which is expressed by the following formula:

[0218]

[0219] In the formula:

[0220] is the second flag;

[0221] is the overcurrent multiple;

[0222] is the multiple threshold.

[0223] If the second flag is set from 0 to 1, the transient overcurrent suppression control is started.

[0224] Further preferably but not limited to, the transient overcurrent suppression control includes: using the additional virtual impedance alone or increasing the original virtual impedance; or using the additional virtual impedance and increasing the original virtual impedance in combination.

[0225] Specifically, the method of increasing the original virtual impedance includes: Such as Figure 4As shown, according to the overcurrent multiple, the original virtual impedance is increased to a set multiple, which is expressed by the following formula:

[0226]

[0227] In the formula:

[0228] is the increased virtual reactance, is a complex variable, is the increased virtual resistance, is the increased virtual impedance;

[0229] is the original virtual reactance, is the original virtual resistance, is the original virtual impedance;

[0230] is the virtual reactance increase coefficient.

[0231] Preferably but not limited to, by looking up a table, according to the overcurrent multiple the corresponding virtual reactance increase coefficient is looked up in real time, and multiplied by the original virtual impedance . Further preferably but not restrictively, the table lookup method includes but is not limited to function calculation, step calculation, interpolation, etc.

[0232] That is to say, the reshaped instantaneous internal potential value minus the grid-connected voltage after obtaining the voltage deviation, virtual impedance and current inner loop control are performed to obtain the current inner loop control reference value, which is expressed by the following formula:

[0233]

[0234] In the formula:

[0235] is the current inner loop control reference value;

[0236] is the reshaped instantaneous internal potential value;

[0237] is the grid-connected voltage;

[0238] is the original virtual reactance, is the original virtual resistance, is the original virtual impedance.

[0239] The ways of adding virtual impedance include: As Figure 5 shown, this is the output diagram of adding virtual impedance of the present invention, and the inverter output current is sampled in real time , and after multiplying with the additional virtual impedance , the compensated voltage is obtained. At this time, the reshaped instantaneous value of the internal potential simultaneously subtracts the compensated voltage and the grid-connected voltage to obtain the voltage deviation, and then performs virtual impedance and inner current loop control to obtain the inner current loop control reference value, which is expressed by the following formula:

[0240]

[0241] Wherein:

[0242] is the compensated voltage;

[0243] is the inverter output current;

[0244] is the original virtual reactance, is the original virtual resistance, is the original virtual impedance;

[0245] is the inner current loop control reference value; !

[0246] is the reshaped instantaneous value of the internal potential, is the compensated voltage, is the grid-connected voltage;

[0247] is the additional virtual reactance, is the additional virtual resistance, is the additional virtual impedance.

[0248] Figure 1 The transient overcurrent suppression strategy presented in combines two methods of increasing the original virtual impedance and the additional virtual impedance. The ways of combining the use of the additional virtual impedance and increasing the original virtual impedance include: real-time sampling of the inverter output current and multiplying it with the additional virtual impedance to obtain the compensated voltage . Subtracting the compensated voltage , the grid-connected voltage and the product of the second flag from the reshaped instantaneous value of the internal potential

[0249]

[0250] Wherein: Note: There seems to be an extra "!" in the translation of line . Please check the original text for accuracy.

[0251] is the reference value for the current inner loop control;

[0252] is the reshaped instantaneous value of the internal electromotive force, is the grid-connected voltage, is the inverter output current, is the additional virtual reactance, is the additional virtual resistance, is the additional virtual impedance, is the second flag, that is is the compensation voltage. If the second flag is set to 1, voltage compensation is performed. If the second flag is set to 0, voltage compensation is not performed;

[0253] is the original virtual reactance, is the original virtual resistance, is the virtual reactance increase coefficient, that is is the original virtual impedance, is the increased virtual impedance.

[0254] Embodiment 2 of the present invention provides an SVI grid-connected voltage phase jump fault grid-forming operation control system, which operates the SVI grid-connected voltage phase jump fault grid-forming operation control method described in Embodiment 1, including:

[0255] A detection unit for detecting the deviation between the self-generated angular frequency and the grid angular frequency. If the deviation exceeds the threshold, within the set time the self-generated angular frequency is maintained at the angular frequency of the previous moment before the fault and the deviation between the self-generated phase angle and the grid phase angle is detected. If the deviation exceeds the threshold, the phase of the equivalent internal electromotive force is compensated;

[0256] An adjustment unit for, after the time adjusting the active power command and reshaping the internal electromotive force according to the grid-connected point voltage during low voltage ride-through or high voltage ride-through;

[0257] A detection unit for detecting whether overcurrent occurs during the entire fault ride-through period. If the amplitude of the grid-connected phase current reaches a set multiple of the rated current, transient overcurrent control is performed by adjusting the virtual impedance.

[0258] Preferably but not restrictively, the control system further includes: an active-frequency control loop and a reactive-voltage control loop;

[0259] The flag unit outputs a first flag and a second flag; when the first flag is set to 1, it indicates that the deviation between the self-generated angular frequency and the grid angular frequency exceeds the threshold, which is used to start the output control of the frozen active power droop integration link and start the equivalent internal potential phase compensation control in the case of phase jump; when the second flag is set to 1, it indicates that a transient overcurrent occurs, which is used to start the transient overcurrent control and suppress the transient overcurrent by adjusting the virtual impedance.

[0260] The active power - frequency control loop includes an active power droop integration link and a freezing link. The active power droop integration link outputs the self-generated angular frequency , and the freezing link freezes the output of the active power droop integration link based on the first flag.

[0261] Preferably but not restrictively, when the first flag is set from 0 to 1, it indicates that the deviation between the self-generated angular frequency and the grid angular frequency exceeds the threshold, and it returns to 0 after a holding time ;

[0262] The first flag passes through a NOT gate to generate the output signal of the freezing link;

[0263] The output signal of the freezing link is multiplied by the deviation of the actual SVI active power to obtain the SVI active power deviation considering the freezing link.

[0264] Preferably but not restrictively, the system further includes: a phase compensation link, which is used to judge whether there is a non-negligible phase jump during the period when the first flag is set to 1; if there is a non-negligible phase jump, the difference between the grid voltage phase angle and the self-generated phase angle is passed through a phase angle dead zone and PI adjustment to generate a compensation phase angle .

[0265] Preferably but not restrictively, the system further includes: an active power command proportional adjustment link, which is used to implement fault ride-through control for possible grid voltage amplitude jumps and generate active power reference adjustment coefficients for non-fault ride-through, high-voltage ride-through, and low-voltage ride-through respectively.

[0266] Preferably but not restrictively, the system further includes: an internal potential reshaping link, which is used to reshape the internal potential according to a set algorithm to maintain the voltage source characteristics during fault ride-through and avoid power imbalance.

[0267] Preferably but not restrictively, the system further includes: a transient overcurrent suppression control module;

[0268] When the second flag is set from 0 to 1, it indicates that a transient overcurrent occurs, and then the transient overcurrent suppression control module starts the transient overcurrent suppression control;

[0269] The transient overcurrent suppression control module includes: an additional virtual impedance link and an original virtual impedance adjustment link;

[0270] The additional virtual impedance link or the original virtual impedance regulation link is put into operation alone, or the additional virtual impedance link and the original virtual impedance regulation link are put into operation in combination, which is used to implement transient overcurrent suppression control.

[0271] Embodiment 3 of the present invention provides an electronic device, including a memory, a processor, and a computer program stored on the memory and operable on the processor. When the computer program is loaded into the processor, it implements the SVI grid voltage phase jump fault grid connection operation control method according to Embodiment 1.

[0272] Embodiment 4 of the present invention provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it implements the SVI grid voltage phase jump fault grid connection operation control method according to Embodiment 1.

[0273] In order to more clearly introduce the prominent substantial features of the present invention and the significant progress brought to the prior art, the following introduces an application example of implementing the present invention. The present invention can enable the SVI to operate stably in a voltage source mode when the grid voltage phase angle jumps, effectively suppress the transient overcurrent spike, and improve the grid connection friendliness and accommodation level of new energy generating units.

[0274] The following further demonstrates the implementation effect of the present invention, and the effectiveness of the present invention is verified by simulation based on matlab / Simulink.

[0275] Figure 6 and Figure 7 It is the verification waveform of the low voltage ride through control strategy in this example. When the fault enters and exits, the grid voltage amplitude and phase both jump. At 0.02 s, the grid voltage drops from 1 p.u. to 0.1 p.u., the grid phase jumps +30° when the fault enters, and the grid-connected point voltage decreases. The SVI operates stably in the voltage source mode during the fault, and the grid phase jumps -30° when the fault exits. During the fault entry and fault recovery phases, the three-phase current is less than 1.5 p.u., and the SVI operates stably in the voltage source mode.

[0276] Figure 8 and Figure 9 It is the verification waveform of the high voltage ride through control strategy in this example. When the fault enters and exits, the grid voltage amplitude and phase both jump. At 0.02 s, the grid voltage rises from 1 p.u. to 1.28 p.u., the grid phase jumps +30° when the fault enters, and the grid-connected point voltage increases. The SVI operates stably in the voltage source mode during the fault, and the grid phase jumps -30° when the fault exits. During the fault entry and fault recovery phases, the three-phase current is less than 1 p.u., and the SVI operates stably in the voltage source mode.

[0277] Figure 10 This is the flowchart for the fault ride-through control of the present invention. First, the angular frequency of the grid voltage is calculated in real time and the self-generated angular frequency The absolute value of the deviation is calculated. When it is detected that , the first flag = 1, the output of the active droop integral link is frozen to 0, and the self-generated angular frequency is maintained at the value at the moment when the first flag is set to 1 and remains constant for time. The absolute value of the deviation between the grid voltage phase and the self-generated phase is calculated in real time. During the period when the first flag is set to 1, if it is detected that , that is, there is a non-negligible phase jump, the equivalent internal potential compensation amount ; if it is detected that , no phase compensation is required. After maintaining time, the first flag is set to 0, and it is necessary to determine again whether there is . If so, repeat the above steps until . The time[[ID=]30] is an adjustable parameter, which can be adjusted according to the actual project, usually not more than dozens of milliseconds.

[0278] The active power command during non-fault ride-through is ; when it is detected that the per-unit value of the grid-connected point voltage 0 ≤ ≤ 0.9 . . During the entire low-voltage ride-through period, the active power command is: = × ; when it is detected that the per-unit value of the grid-connected point voltage ≥ 1.1 . . During the entire high-voltage ride-through period, the active power command is: = × ; During the fault ride-through, the internal potential is reshaped to maintain the voltage source characteristics during the fault ride-through and avoid power imbalance.

[0279] At the same time, by detecting the amplitude of the grid-connected point current , the amplitude of the grid-connected point current is calculated in real time and the ratio with the rated current value , that is, the overcurrent multiple = / , when it is detected that the overcurrent multiple , the transient overcurrent suppression strategy is triggered, and the second flag Set to 1 from 0. On the one hand, according to the overcurrent multiple size, look up the table in real time to obtain the increased original virtual impedance coefficient , and the table look-up methods include but are not limited to function calculation, step calculation, interpolation, etc.; on the other hand, sample the inverter output current in real time, and multiply it by the additional virtual impedance ( + ) to obtain the compensation voltage . At this time, the reshaped instantaneous internal potential simultaneously subtracts the compensation voltage , the grid-connected voltage and the product of the second flag to obtain the voltage deviation, and then perform virtual impedance and current inner loop control. As Figure 1 shown, the combination of the two is adopted to suppress the transient overcurrent, which is expressed by the following formula:

[0280]

[0281] In the formula:

[0282] is the reference value of the current inner loop control;

[0283] is the reshaped instantaneous internal potential;

[0284] is the grid-connected voltage;

[0285] is the inverter output current;

[0286] is the additional virtual reactance, is a complex variable, is the additional virtual resistance, is the additional virtual impedance;

[0287] is the second flag;

[0288] is the original virtual reactance, is the original virtual resistance, is the original virtual impedance;

[0289] is the magnification factor of the virtual reactance increase.

[0290] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: it is still possible to modify the specific implementation manners of the present invention or make equivalent replacements, and any modification or equivalent replacement that does not depart from the spirit and scope of the present invention shall be covered by the protection scope of the claims of the present invention.

Claims

1. A fault grid-forming operation control method under SVI grid voltage phase jump, characterized in that It includes the following steps: Detect the deviation between the self-generated angular frequency and the grid angular frequency. If the deviation exceeds the threshold, within the set time maintain the self-generated angular frequency unchanged at the angular frequency at the moment before the fault and detect the deviation between the self-generated phase angle and the grid phase angle. If the deviation exceeds the threshold, compensate the phase of the equivalent internal potential; Time After that, according to the grid connection point voltage, during low voltage ride through or high voltage ride through, adjust the active power command and reshape the internal potential; During the entire fault ride-through period, detect whether overcurrent occurs. If the amplitude of the grid-connected phase current reaches a set multiple of the rated current, perform transient overcurrent suppression control by adjusting the virtual impedance.

2. A method for controlling the operation of a fault-forming network under SVI grid voltage phase jump according to claim 1, characterized in that: Set the first flag , indicating whether the deviation between the self-generated angular frequency and the grid angular frequency exceeds a threshold, which is expressed by the following formula: In the formula: is the first flag; is the self-generated angular frequency; is the angular frequency of the grid voltage; is the angular frequency deviation threshold; The first flag When set from 0 to 1, the start time Starts timing, the first flag The holding time when set from 0 to 1 Returns to 0 after that.

3. A method for controlling the operation of a fault-forming network under SVI grid voltage phase jump according to claim 2, characterized in that: In the active-power / frequency control loop configuration freeze link, it is used to freeze the self-generated angular frequency output by the active-power droop integral link under set conditions , and take the logical NOT operation on the first flag as the output signal of the freeze link; Output signal of the freezing link Deviation from the actual SVI active power Multiply to obtain the SVI active power deviation considering the freezing link, which is expressed by the following formula: In the formula: To account for the active power deviation of SVI in the freezing link; is the actual SVI active power deviation.

4. A method for controlling the operation of a fault-forming network under SVI grid voltage phase jump according to claim 2 or 3, characterized in that: Real-time calculation of the absolute value of the deviation between the grid voltage phase and the self-generated phase, and comparison with a threshold value includes: If the first flag is set to 1 during , there will be a non-negligible phase jump, and the equivalent internal potential compensation amount ; if is detected, no phase compensation is required; Grid voltage phase angle and the self-generated phase angle after passing through the phase angle dead zone and PI regulation, generate a compensation phase angle , which is expressed by the following formula: In the formula: To compensate for the phase angle; is the phase angle deviation threshold; is the phase angle of the grid connection point voltage; For active power control, self-generated phase angles; is the transfer function of the PI link.

5. A method for controlling the operation of a fault-forming network under SVI grid voltage phase jump according to claim 2 or 3, characterized in that: The first flag After resetting to zero, continue to implement fault ride-through control for possible grid voltage magnitude jumps, including: taking the active power command during non-fault ride-through as a reference, adjusting the active power command during fault ride-through according to a set ratio, which is expressed by the following formula: In the formula: is the active power command during non-fault ride-through, is the active power command during fault ride-through; P eF is the grid-connected active power during the fault, P e is the grid-connected active power before the fault; δ is the power angle before the fault, δ F is the power angle during the fault; is the active power reference adjustment coefficient for high-voltage ride-through; is the active power reference adjustment coefficient for low voltage ride through; is the grid connection point voltage before the fault, is the grid connection point voltage during the fault, is the grid voltage before the fault, is the grid voltage during the fault, is the per-unit value of the grid connection point voltage.

6. A method for controlling the operation of a fault-forming network under SVI grid voltage phase jump according to claim 2 or 3, characterized in that: Continue to implement fault ride-through control for possible grid voltage amplitude jumps, and also include: internal potential reshaping for maintaining the voltage source characteristics during fault ride-through and avoiding power imbalance, which is expressed by the following formula: In the formula: The amplitude of the equivalent internal potential of the SVI reshaped under a fault; is the amplitude of the equivalent internal electromotive force self-generated before the fault; is an intermediate variable; U gN is the rated voltage of the power grid; k c It is the ratio of the maximum allowable overcurrent of the inverter to the rated current; I g is the grid-connected current; Z eqF is the total impedance from the SVI converter port to the grid during a fault; Z eq is the total impedance from the SVI converter port to the power grid before the fault; k F is the depth of voltage sag.

7. A method for controlling the operation of a fault-forming network under SVI grid voltage phase jump according to claim 2 or 3, characterized in that: Set the second flag , indicating whether a transient overcurrent occurs; if the detected overcurrent multiple is greater than or equal to the multiple threshold, then set the second flag from 0 to 1; if the detected overcurrent multiple is less than the multiple threshold, then keep the second flag set to 0, which is expressed by the following formula: In the formula: is the second flag; is the overcurrent multiple; is the absolute value of the amplitude of the grid-connected three-phase current, is the rated current; is the multiple threshold value; Second flag When it is set from 0 to 1, the transient overcurrent suppression control is started.

8. A method for controlling the operation of a fault-forming network under SVI grid voltage phase jump according to claim 7, characterized in that: The transient overcurrent suppression control includes: Using the method of adding an additional virtual impedance alone or increasing the original virtual impedance; or Using a combination of adding an additional virtual impedance and increasing the original virtual impedance.

9. A method for controlling the operation of a fault-forming network under SVI grid voltage phase jump according to claim 8, characterized in that: The method of increasing the original virtual impedance includes: According to the overcurrent multiple, increase the original virtual impedance to a set multiple, which is expressed by the following formula: In the formula: is the increased virtual reactance, is a complex variable, is the increased virtual resistance, is the increased virtual impedance; is the original virtual reactance, is the original virtual resistance, is the original virtual impedance; is the corresponding virtual reactance increase factor obtained by looking up the table in real time according to the overcurrent multiple; The method of adding an additional virtual impedance includes: Real-time sampling of the inverter output current , and multiplying it by an additional virtual impedance to obtain a compensation voltage , subtracting the compensation voltage from the reshaped instantaneous value of the internal electromotive force and the grid-connected voltage to obtain a voltage deviation, and then performing virtual impedance and current inner-loop control to obtain the current inner-loop control reference value, which is expressed by the following formula: In the formula: is the compensation voltage; is the output current of the inverter; is the original virtual reactance, is the original virtual resistance, is the original virtual impedance; is the reference value for the current inner loop control; is the reshaped instantaneous value of the internal potential, is the compensation voltage, is the grid-connected voltage; is the additional virtual reactance, is the additional virtual resistance, is the additional virtual impedance.

10. A method for controlling the operation of a fault-forming network under SVI grid voltage phase jump according to claim 8, characterized in that: The ways of combining the use of additional virtual impedance and increasing the original virtual impedance include: real-time sampling of the inverter output current , and multiplying it with the additional virtual impedance to obtain a compensation voltage . Subtracting the compensation voltage from the reshaped instantaneous value of the internal potential , multiplying the grid-connected voltage with the second flag to obtain a voltage deviation, and then performing virtual impedance and current inner-loop control to obtain a current inner-loop control reference value, which is expressed by the following formula: In the formula: is the reference value for the current inner loop control; is the reshaped instantaneous value of the internal potential, is the grid-connected voltage, is the inverter output current, is the additional virtual reactance, is the additional virtual resistance, is the additional virtual impedance, is the second flag; is the original virtual reactance, is the original virtual resistance, is the virtual reactance increase factor.

11. A fault network-forming operation control system under SVI grid voltage phase jump, which operates the fault network-forming operation control method under SVI grid voltage phase jump according to any one of claims 1 to 10, characterized in that, It includes: The detection unit is used to detect the deviation between the self-generated angular frequency and the grid angular frequency. If the deviation exceeds the threshold, within the set time , keep the self-generated angular frequency unchanged at the angular frequency of the moment before the fault and detect the deviation between the self-generated phase angle and the grid phase angle. If the deviation exceeds the threshold, compensate the phase of the equivalent internal potential; An adjustment unit for adjusting, after a time the active power command and reshaping the internal electromotive force according to the grid connection point voltage during low voltage ride-through or high voltage ride-through; A detection unit for detecting whether overcurrent occurs during the entire fault ride-through period. If the amplitude of the grid-connected phase current reaches a set multiple of the rated current, perform transient overcurrent suppression control by adjusting the virtual impedance.

12. A fault-forming network operation control system under SVI grid voltage phase jump according to claim 11, characterized in that: The control system further includes: an active-power - frequency control loop and a reactive-power - voltage control loop; The flag unit outputs a first flag and a second flag; when the first flag is set to 1, it indicates that the deviation between the self-generated angular frequency and the grid angular frequency exceeds the threshold, and is used to start freezing the output control of the active power droop integration link and start the equivalent internal potential phase compensation control in the case of phase jump; when the second flag is set to 1, it indicates that transient overcurrent occurs, and is used to start transient overcurrent control to suppress transient overcurrent by adjusting the virtual impedance; The active-power frequency control loop includes an active-power droop integration link and a freezing link, and the active-power droop integration link outputs a self-generated angular frequency , and the freezing link freezes the output of the active-power droop integration link based on a first flag.

13. A fault grid-forming operation control system under SVI grid voltage phase jump according to claim 12, characterized in that: The first flag is set from 0 to 1, indicating that the deviation between the self-generated angular frequency and the grid angular frequency exceeds the threshold, and is restored to 0 after a holding time and then restored to 0; The first flag passes through a NOT gate to generate the output signal of the freezing link; The output signal of the freezing link is multiplied by the actual SVI active power deviation to obtain the SVI active power deviation considering the freezing link.

14. A fault grid-forming operation control system under SVI grid voltage phase jump according to claim 13, characterized in that: The system further includes: a phase compensation unit, which is configured to, during the period when the first flag is set to 1, determine whether there is a non-negligible phase jump; if there is a non-negligible phase jump, a compensation phase angle is generated after the difference between the grid voltage phase angle and the self-generated phase angle passes through a phase angle dead zone and PI regulation .

15. A fault grid-forming operation control system under SVI grid voltage phase jump according to claim 13, characterized in that: The system further includes: an active command proportional adjustment link, which is used to implement fault ride-through control for possible grid voltage amplitude jumps and generate active reference adjustment coefficients for non-fault ride-through, high-voltage ride-through, and low-voltage ride-through respectively.

16. A fault grid-forming operation control system under SVI grid voltage phase jump according to claim 13, characterized in that: The system further includes: an internal potential reshaping link, which is used to reshape the internal potential according to a set algorithm, maintain the voltage source characteristics during fault ride-through, and avoid power imbalance.

17. A fault grid-forming operation control system under SVI grid voltage phase jump according to claim 12, characterized in that: The system further includes: a transient overcurrent suppression control module; The second flag is set from 0 to 1, indicating the occurrence of transient overcurrent, and then the transient overcurrent suppression control module starts transient overcurrent suppression control; The transient overcurrent suppression control module includes: an additional virtual impedance link and an original virtual impedance adjustment link; The additional virtual impedance link or the original virtual impedance adjustment link is separately put into operation, or the additional virtual impedance link and the original virtual impedance adjustment link are put into operation in combination to implement transient overcurrent suppression control.

18. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the computer program is loaded into the processor, it implements the SVI grid voltage phase jump fault grid-forming operation control method according to any one of claims 1 to 10.

19. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the SVI grid voltage phase jump fault grid-forming operation control method according to any one of claims 1 to 10.

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