Method of operating an inverter-based resource connected to a series compensated transmission system

Abstract

The present invention relates to a method of operating an inverter-based resource connected to a series-compensated transmission system. A method for operating an inverter-based resource includes monitoring a current magnitude value in the inverter-based resource. The method also includes monitoring a voltage magnitude value in the inverter-based resource. Further, the method includes comparing the current magnitude value in the inverter-based resource to a primary current threshold. Moreover, the method includes comparing the voltage magnitude value in the inverter-based resource to a voltage threshold. As such, the method also includes disabling switching of switching elements of a power converter when the current magnitude value increases above the primary current threshold and the voltage magnitude value decreases below the voltage threshold to bypass the switching elements of the power converter until excess energy in the inverter-based resource is dissipated.

Description

Technical Field

[0001] This disclosure generally relates to inverter-based resources, and more particularly to methods for operating inverter-based resources (such as electric power systems) connected to a series-compensated transmission system. Background Technology

[0002] Wind turbines have received increasing attention as a renewable energy source. Wind turbines use wind to generate electricity. The wind causes multiple blades connected to a rotor to rotate. The blade rotation caused by the wind causes the rotor's shaft to rotate, which is connected to a generator that generates electricity. Some wind turbines include a double-fed asynchronous generator (DFAG) (often also called a double-fed induction generator (DFIG)) to convert wind energy into electrical power suitable for output to the grid. The DFAG is typically connected to a converter that regulates the flow of electrical power between the DFAG and the grid. More specifically, the converter allows the wind turbine to output electrical power at the grid frequency, regardless of the rotational speed of the wind turbine blades.

[0003] A typical DFAG system includes a wind-driven DFAG with a rotor and a stator. The DFAG stator is connected to the power grid via a stator bus. A power converter is used to connect the DFAG rotor to the power grid. The power converter can be a two-stage power converter, consisting of both a rotor-side converter and a line-side converter. The rotor-side converter receives alternating current (AC) power from the rotor via the rotor bus and converts the AC power to DC power. The line-side converter then converts the DC power back to AC power with a suitable output frequency (such as the grid frequency). The AC power is supplied to the power grid via the line bus. Auxiliary power feeders can be connected to the line bus to supply power to components used in the wind turbine system, such as the fans, pumps, motors, and other components of the wind turbine system.

[0004] Inverter-based resources (IBRs) including power converters (such as wind turbines, solar inverters, or energy storage systems) are generally sensitive to currents exceeding their design ratings. Excessive current can flow in these power converters if a sudden imbalance in the energy input / output of the power system surrounding them occurs, and if the stored energy in the system has a path for dissipation through the converter. Such a sudden energy imbalance can be caused by the onset and / or clearance of multiple faults. This can result in excess energy in the power converter, which can cause damage. For example, in a DFAG (Diverterless Power Generation Amplifier), a grid fault causing a sudden drop in voltage results in a sudden decrease in the power / energy output from the system. Due to the stored energy within the generator's magnetic components, this event causes an increase in voltage induced in the DFAG's rotor circuit, which can lead to a high current flowing in the converter.

[0005] Another example of high current flowing in a power converter involves a series-compensated transmission system. During a grid fault, the high short-circuit current flowing from the grid through a series capacitor bank causes a large energy accumulation in the series capacitors. Upon clearing the fault, the energy stored in the series capacitors is dissipated through an interconnected transmission system, which may include a nearby integrated circuit breakers (IBRs). This sudden discharge of energy from the series capacitor bank can manifest as high current and / or voltage in a nearby IBR. For this event, the IBR should avoid tripping, take control actions to attempt and maintain the voltage / current within the equipment's capacity, and dampen the resonance caused by the series compensation system.

[0006] Therefore, a previous method for managing high current in the power converter of an IBR is provided in U.S. Application No. 15 / 604921, filed May 25, 2017, entitled "Methods for Operating Electrical Power Systems". The disclosed method involves detecting a high current in the converter, comparing it to a threshold, and deciding to shut down the converter's gating if the detected current exceeds the threshold. This method is effective when the amount of energy in the system is rapidly dissipated and the gating can be quickly restored when stored energy is dissipated (e.g., by a dynamic braking circuit).

[0007] However, in some cases (where there is resonance in the system (such as resonance due to a series capacitor bank) or the energy source causing the high current is large relative to the converter's dissipation capacity), it can be beneficial to continue gating despite the high current in the converter. This benefit stems from the converter's ability to mitigate high voltage and / or current through control actions, which would otherwise be impossible if gating were disabled.

[0008] Therefore, this disclosure relates to systems and methods for distinguishing between events that cause high currents and can be successfully managed by disabling gating, and events that can be optimally managed by continuing gating in an attempt to mitigate the high current level via control actions. Summary of the Invention

[0009] Aspects and advantages of the invention will be set forth in part in the description which follows, or may be apparent from the description, or may be learned by practice of the invention.

[0010] In one aspect, this disclosure relates to a method for operating an inverter-based resource. The method includes monitoring a current quantity value in the inverter-based resource. The method also includes monitoring a voltage quantity value in the inverter-based resource. Furthermore, the method includes comparing the current quantity value in the inverter-based resource with a primary current threshold. Additionally, the method includes comparing the voltage quantity value in the inverter-based resource with a voltage threshold. Accordingly, the method further includes disabling the switching of a power converter's switching element when the current quantity value increases above the primary current threshold and the voltage quantity value decreases below the voltage threshold, thereby bypassing the power converter's switching element until excessive energy in the inverter-based resource is dissipated.

[0011] In an embodiment, the method may further include disabling the switching of the switching element of the power converter when the current value increases above a primary current threshold and the voltage value decreases below a voltage threshold.

[0012] In another embodiment, the inverter-based resource may be a doubly-fed asynchronous generator (DFAG). In such an embodiment, the DFAG may have a generator rotor and a generator stator. In such an embodiment, the method may include detecting a voltage level in the generator stator.

[0013] In another embodiment, the voltage threshold can be set to the voltage level observed in response to a nearby grid fault. For example, in such an embodiment, the voltage threshold can range from approximately 0.1 pu to approximately 0.5 pu.

[0014] In another embodiment, the method distinguishes between high current caused by the discharge of energy stored within the inverter-based resources and high current caused by the discharge of energy from sources outside the inverter-based resources by requiring not only the current value to increase above the primary current threshold but also the voltage value to decrease below the voltage threshold before disabling the switch.

[0015] In a particular embodiment, the method may further include: comparing a current magnitude in the power converter with a secondary current threshold after a disable event occurs; and enabling the switching of a switching element in the power converter when the current magnitude is less than the secondary current threshold. In such an embodiment, the secondary current threshold differs from the primary current threshold.

[0016] In some embodiments, the power converter may include a DC link and a dynamic brake. Therefore, in some embodiments, the dynamic brake may be gated to open after a disablement occurs.

[0017] In another embodiment, the inverter-based resources may be a full-conversion wind turbine power system, a solar power system, an energy storage system, or a combination thereof.

[0018] In another aspect, this disclosure relates to a method for operating an inverter-based resource connected to a series-compensated transmission system. The series-compensated transmission system has at least one series capacitor. The method includes monitoring voltage and current values ​​at the inverter-based resource via the inverter-based resource. When at least one of the current or voltage values ​​exceeds a device rating, the method includes using both the current and voltage values ​​to determine whether the type of the high-current event is due to energy dissipated from the at least one series capacitor. Furthermore, the method includes implementing control actions based on the type of the high-current event.

[0019] In embodiments, the type of high-current event may include, for example, fault clearing in a series-compensated transmission system or a grid fault.

[0020] In one embodiment, dissipated energy may be received from a series capacitor. In such an embodiment, when dissipated energy is received from a series capacitor, implementing control actions based on the type of high-current event occurring in the inverter-based resource may include preventing the disablement of the bridge switch of the inverter-based power converter via the inverter-based resource.

[0021] In another embodiment, when dissipated energy is received from the series capacitor, implementing control actions based on the type of high current event occurring in the inverter-based resource may include maintaining current and voltage values ​​within the device ratings of the inverter-based resource via the inverter-based resource.

[0022] In an additional embodiment, when dissipated energy is received from the series capacitor, implementing control actions based on the type of high-current event occurring in the inverter-based resources may further include damping the series resonance from the series compensation system, which causes oscillations in voltage and current magnitudes.

[0023] In an alternative embodiment, dissipated energy may be received from a power grid. In such an embodiment, when dissipated energy is received from the power grid, implementing control actions based on the type of high-current events occurring in the inverter-based resources may include disabling the bridge switch of the power converter when the current value increases above a primary current threshold and the voltage value decreases below a voltage threshold.

[0024] In another aspect, this disclosure relates to a wind power system connected to a series-compensated transmission system. The series-compensated transmission system has at least one series capacitor. The wind power system includes a doubly-fed asynchronous generator having a generator rotor and a generator stator, a power converter coupled to the generator rotor, and a controller communicatively coupled to the power converter. The power converter has a rotor-side converter and a line-side converter. The rotor-side converter or the line-side converter includes a plurality of switching elements defining a bridge. The controller is configured to perform a plurality of operations, including but not limited to receiving voltage and current feedback from the wind turbine power system, determining voltage and current magnitudes at the wind power system based on the voltage and current feedback, determining the type of a high-current event occurring using both the current and voltage magnitudes when at least one of the current or voltage magnitudes exceeds a device rating, and selecting between disabling or enabling the bridge switches of the rotor-side converter or the line-side converter based on the type of the high-current event.

[0025] In an embodiment, the type of high-current event may include grid faults in a power grid or fault clearing in a wind power system.

[0026] Technical Solution 1. A method for operating an inverter-based resource, the inverter-based resource comprising a power converter having a plurality of switching elements, the method comprising:

[0027] Monitor the current values ​​in the inverter-based resources;

[0028] Monitor the voltage values ​​in the inverter-based resources;

[0029] Compare the current value in the inverter-based resource with the primary current threshold.

[0030] Compare the voltage value in the inverter-based resources with a voltage threshold; and...

[0031] When the current value increases above the primary current threshold and the voltage value decreases below the voltage threshold, the switching of the switching element of the power converter is disabled to bypass the switching element of the power converter until excess energy in the inverter-based resources is dissipated.

[0032] Technical Solution 2. The method according to Technical Solution 1, characterized in that the method further includes disabling the switching of the switching element of the power converter when the current value increases to above the primary current threshold and the voltage value decreases to below the voltage threshold.

[0033] Technical Solution 3. The method according to Technical Solution 1, wherein the inverter-based resources include a doubly fed asynchronous generator (DFAG).

[0034] Technical Solution 4. The method according to Technical Solution 3, characterized in that the DFAG includes a generator rotor and a generator stator, and the method further includes detecting the voltage value in the generator stator.

[0035] Technical Solution 5. The method according to Technical Solution 1, characterized in that the voltage threshold is set to the voltage level observed for a nearby power grid fault, and the voltage threshold ranges from about 0.1 pu to about 0.5 pu.

[0036] Technical Solution 6. The method according to Technical Solution 1, characterized in that, by requiring not only the current value to increase above the primary current threshold but also the voltage value to decrease below the voltage threshold before disabling the switch, the method distinguishes between high current caused by the discharge of energy stored within the inverter-based resource and high current caused by the discharge of energy from sources outside the inverter-based resource.

[0037] Technical Solution 7. The method according to Technical Solution 1, characterized in that the method further comprises:

[0038] After the disablement occurs, the current value in the power converter is compared with the secondary current threshold; and

[0039] When the current value is less than the secondary current threshold, the switching element of the power converter is activated.

[0040] Technical Solution 8. The method according to Technical Solution 7, wherein the secondary current threshold is different from the primary current threshold.

[0041] Technical Solution 9. The method according to Technical Solution 1, characterized in that the power converter further includes a DC link and a dynamic brake, wherein the dynamic brake is gated to open after a disable event occurs.

[0042] Technical Solution 10. The method according to Technical Solution 1, wherein the inverter-based resources include at least one of a full-conversion wind turbine power system, a solar power system, or an energy storage system.

[0043] Technical Solution 11. A method for operating inverter-based resources connected to a series-compensated transmission system, the series-compensated transmission system having at least one series capacitor, the method comprising:

[0044] The voltage and current values ​​at the inverter-based resources are monitored via the inverter-based resources.

[0045] When at least one of the current value or the voltage value exceeds the device rating, both the current value and the voltage value are used to determine whether the type of high-current event is due to energy dissipated from the at least one series capacitor; and

[0046] Control actions are implemented based on the type of the high-current event.

[0047] Technical Solution 12. The method according to Technical Solution 11, wherein the type of the high current event includes at least one of fault clearing or grid fault in the series-compensated transmission system.

[0048] Technical Solution 13. The method according to Technical Solution 11, characterized in that the dissipated energy is received from the series capacitor.

[0049] Technical Solution 14. The method according to Technical Solution 13, characterized in that, when the dissipated energy is received from the series capacitor, implementing the control action based on the type of the high current event occurring in the inverter-based resources further includes:

[0050] The power converter based on the inverter is prevented from being disabled via the inverter-based resources.

[0051] Technical Solution 15. The method according to Technical Solution 13, characterized in that, when the dissipated energy is received from the series capacitor, implementing the control action based on the type of the high current event occurring in the inverter-based resources further includes:

[0052] The current and voltage values ​​are maintained within the device ratings of the inverter-based resources.

[0053] Technical Solution 16. The method according to Technical Solution 13, characterized in that, when the dissipated energy is received from the series capacitor, implementing the control action based on the type of the high current event occurring in the inverter-based resources further includes:

[0054] The damping comes from the series resonance of the series compensation system, which causes oscillations in the voltage and current values.

[0055] Technical Solution 17. The method according to Technical Solution 11, wherein the dissipated energy is received from the power grid.

[0056] Technical Solution 18. The method according to Technical Solution 17, characterized in that, when the dissipated energy is received from the power grid, implementing the control action based on the type of the high current event occurring in the inverter-based resources further includes:

[0057] When the current value increases above the primary current threshold and the voltage value decreases below the voltage threshold, the power converter switch is disabled.

[0058] Technical Solution 19. A wind power system connected to a series-compensated transmission system, the series-compensated transmission system having at least one series capacitor, the wind power system comprising:

[0059] A doubly-fed asynchronous generator, which includes a generator rotor and a generator stator;

[0060] A power converter coupled to the generator rotor, the power converter including a rotor-side converter and a line-side converter, the rotor-side converter or the line-side converter including a plurality of switching elements defining a bridge;

[0061] A controller, communicatively coupled to the power converter, is configured to perform a plurality of operations, the plurality of operations including:

[0062] Receive voltage and current feedback from the wind turbine power system;

[0063] The voltage and current values ​​at the wind power system are determined based on the voltage and current feedback.

[0064] When at least one of the current value or the voltage value exceeds the device's rated value, both the current value and the voltage value are used to determine the type of high-current event that has occurred; and

[0065] Based on the type of the high-current event, a bridge switch is selected between disabling or enabling the rotor-side converter or the line-side converter.

[0066] Technical Solution 20. The wind power system according to Technical Solution 19, wherein the type of the high current event includes at least one of a grid fault in the power grid or a fault clearing in the wind power system.

[0067] These and other features, aspects, and advantages of the invention will become more readily understood with reference to the following description and the appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. Attached Figure Description

[0068] The invention (including its preferred mode) is fully disclosed and can be practiced by one of ordinary skill in the art in the description with reference to the accompanying drawings, in which:

[0069] Figure 1 A perspective view of a wind turbine according to an embodiment of the present disclosure;

[0070] Figure 2 The figure shows a perspective interior view of the nacelle of a wind turbine according to an embodiment of the present disclosure;

[0071] Figure 3 The illustration may be a schematic diagram of one embodiment of suitable components that may be included in the controller of a wind turbine and / or electric power system;

[0072] Figure 4 The figure illustrates an electric power system according to an embodiment of the present disclosure;

[0073] Figure 5 The figure shows a flowchart of one embodiment of a method according to an embodiment of the present disclosure;

[0074] Figure 6 The figure shows a simplified schematic diagram of an embodiment of a series-compensated transmission system according to an embodiment of the present disclosure; and

[0075] Figure 7 The illustration shows a flowchart of another embodiment of a method according to one embodiment of the present disclosure. Detailed Implementation

[0076] Reference will now be made in detail to embodiments of the invention, one or more of which are illustrated in the accompanying drawings. The various examples are provided by way of explanation rather than limitation of the invention. Indeed, it will be apparent to those skilled in the art that many modifications and variations can be made to the invention without departing from its scope or spirit. For example, a feature illustrated or described as a part of one embodiment may be used with another embodiment to produce yet another further embodiment. Therefore, it is intended that the invention cover such modifications and variations as fall within the scope of the appended claims and their equivalents.

[0077] Generally, this disclosure relates to systems and methods for determining whether to disable converter gating by considering both current and voltage magnitudes. Accordingly, this disclosure requires that two conditions (e.g., high current and low voltage) be met to disable gating. These conditions generally occur immediately after the fault begins in the DFAG, where the voltage at the DFAG drops suddenly and the current in the rotor increases suddenly. Therefore, for these conditions, disabling gating to allow excessive energy stored in the electrical system of the DFAG to dissipate rapidly is beneficial. Gating can then be restored when the current decreases to an acceptable level.

[0078] However, during fault clearing, the voltage at the IBR increases from a low level to a higher level. In a series-compensated transmission system, series resonance causes oscillations in voltage and current in the network during fault clearing. If the power rating of the series capacitor bank is large relative to the power rating of the IBR, these voltage and current oscillations in the system can be large in amplitude and overwhelm the IBR. These large oscillations can drive current and voltage beyond the IBR device's rating. Therefore, it is less desirable to disable gating during these events, as the runaway prevention converter that causes the gating to be disabled can dampen subsynchronous resonance and mitigate overvoltage and undervoltage due to oscillations.

[0079] During these events, the voltage level at the IBR tends to be higher than that seen during grid faults. Therefore, by also considering the voltage level, the high current flowing in the power converter during this event can be distinguished from the high current caused by grid faults such as low-voltage ride-through (LVRT) events. Thus, if the voltage threshold is set relatively low, the systems and methods of this disclosure are unlikely to cause disable gating for this type of event. Accordingly, the systems and methods of this disclosure provide the benefit of allowing the power converter to continue attempting to manage large voltage oscillations and to continue damping subsynchronous oscillations via appropriate control actions.

[0080] As used herein, inverter-based resources broadly refer to electrical installations that generate or absorb electrical power through the switching of power electronics. Therefore, inverter-based resources can include wind turbine generators, solar inverters, energy storage systems, STATCOM, or hydroelectric systems.

[0081] Now refer to the attached diagram, Figure 1The illustration shows a perspective view of one embodiment of a wind turbine 10. As shown, the wind turbine 10 includes a tower 12 extending from a support surface 14, a nacelle 16 mounted on the tower 12, and a rotor 18 coupled to the nacelle 16. The rotor 18 includes a rotatable hub 20 and at least one rotor blade 22 coupled to and extending outward from the hub 20. For example, in the illustrated embodiment, the rotor 18 includes three rotor blades 22. However, in alternative embodiments, the rotor 18 may include more or fewer than three rotor blades 22. The individual rotor blades 22 may be spaced around the hub 20 to allow the rotor 18 to rotate so that kinetic energy can be converted from wind into usable mechanical energy, and subsequently, into electrical energy. For example, the hub 20 may be rotatably coupled to a generator 24 positioned within the nacelle 16. Figure 2 ), to allow the generation of electrical energy.

[0082] As shown, the wind turbine 10 may also include a turbine control system or turbine controller 26 centralized within the nacelle 16. However, it should be understood that the turbine controller 26 may be located on or anywhere within the wind turbine 10, on the support surface 14, or substantially in any other location. The turbine controller 26 may be substantially configured to control various operating modes (e.g., start-up or stop sequences) and / or components of the wind turbine 10. For example, the controller 26 may be configured to control the blade pitch or pitch angle (i.e., the angle at which the rotor blade 22 is viewed relative to the wind direction 28) of each of the rotor blades 22 by adjusting the angular position of at least one rotor blade 22 relative to the wind, in order to control the load on the rotor blade 22. For example, the turbine controller 26 may transmit appropriate control signals / commands to various pitch actuators or pitch adjustment mechanisms 32 of the wind turbine 10. Figure 2 The turbine controller 26 can control the pitch angle of the rotor blades 22 individually or simultaneously. Specifically, the rotor blades 22 can be rotatably mounted to the hub 20 by one or more pitch bearings (not shown) such that the pitch angle can be adjusted by rotating the rotor blades 22 about their pitch axis 34 using the pitch adjustment mechanism 32. Furthermore, when the wind direction 28 changes, the turbine controller 26 can be configured to control the yaw direction of the nacelle 16 about the yaw axis 36 to position the rotor blades 22 relative to the wind direction 28, thereby controlling the load acting on the wind turbine 10. For example, the turbine controller 26 can be configured to transmit control signals / commands to the yaw drive mechanism 38 of the wind turbine 10. Figure 2 This allows the cabin 16 to rotate around the yaw axis 36.

[0083] Furthermore, the turbine controller 26 can be configured to control the torque of the generator 24. For example, the turbine controller 26 can be configured to transmit control signals / commands to the generator 24 to modulate the magnetic flux generated within the generator 24, thereby adjusting the torque demand on the generator 24. Such temporary derating of the generator 24 can reduce the rotational speed of the rotor blades 22, thereby reducing the aerodynamic loads acting on the blades 22 and the reaction loads on various other components of the wind turbine 10.

[0084] It should be recognized that the turbine controller 26 may generally include a computer or any other suitable processing unit. Therefore, in several embodiments, the turbine controller 26 may include one or more processors and associated memory devices configured to perform a variety of computer-implemented functions, such as... Figure 3 The processor is shown and discussed herein. As used herein, the term "processor" refers not only to integrated circuits known in the art as included in a computer, but also to controllers, microcontrollers, microcomputers, programmable logic controllers (PLCs), application-specific integrated circuits (ASICs), and other programmable circuits. Additionally, the memory device(s) of the turbine controller 26 may generally include memory elements(s), including but not limited to computer-readable media (e.g., random access memory (RAM)), computer-readable non-volatile media (e.g., flash memory), floppy disks, compact disc-read-only memory (CD-ROM), magneto-optical disks (MOD), digital versatile discs (DVDs), and / or other suitable memory elements. Such memory devices(s) may be generally configured to store suitable computer-readable instructions that, when implemented by the processor(s), configure the controller 26 to perform a variety of computer-implemented functions, including but not limited to performing proportional-integral-derivative ("PID") control algorithms (which include various calculations within one or more PID control loops), and a variety of other suitable computer-implemented functions. In addition, the turbine controller 26 may also include multiple input / output channels for receiving inputs from sensors and / or other measuring devices and for sending control signals to various components of the wind turbine 10.

[0085] Additionally, it should be understood that a controller may be a single controller or may include multiple components (such as a pitch controller and / or a yaw controller, which communicate with a central controller for specific control of pitch and yaw as discussed). Furthermore, the term "controller" may also include combinations of computers, processing units, and / or related components that communicate with each other.

[0086] Now for reference Figure 2The illustration shows a simplified internal view of one embodiment of the nacelle 16 of a wind turbine 10. As shown, a generator 24 may be disposed within the nacelle 16. Generally, the generator 24 may be coupled to the rotor 18 of the wind turbine 10 to generate electrical power from rotational energy generated by the rotor 18. For example, the rotor 18 may include a main rotor shaft 40 coupled to a hub 20 for rotation therewith. The generator 24 may then be coupled to the rotor shaft 40 such that rotation of the rotor shaft 40 drives the generator 24. For example, in the illustrated embodiment, the generator 24 includes a generator shaft 42 rotatably coupled to the rotor shaft 40 via a gearbox 44. However, in other embodiments, it should be appreciated that the generator shaft 42 may be directly rotatably coupled to the rotor shaft 40. Alternatively, the generator 24 may be directly rotatably coupled to the rotor shaft 40 (often referred to as a "direct-drive wind turbine").

[0087] It should be recognized that the rotor shaft 40 can be generally supported within the nacelle by a support frame or base plate 46 positioned on top of the wind turbine tower 12. For example, the rotor shaft 40 can be supported by the base plate 46 via a pair of shaft supports 48, 50 mounted to the base plate 46.

[0088] Additionally, as indicated herein, the turbine controller 26 may also be located within the nacelle 16 of the wind turbine 10. For example, as shown in the illustrated embodiment, the turbine controller 26 is housed within a control cabinet 52, which is mounted to a portion of the nacelle 16. However, in other embodiments, the turbine controller 26 may be located on and / or within the wind turbine 10 at any other suitable location, or at any suitable location remote from the wind turbine 10. Furthermore, as described herein, the turbine controller 26 may also be communicatively coupled to various components of the wind turbine 10 for generally controlling the wind turbine and / or such components. For example, the turbine controller 26 may be communicatively coupled to the yaw drive mechanism(s) 38 of the wind turbine 10 for controlling and / or changing the direction 28 of the nacelle 16 relative to the wind. Figure 1 The turbine controller 26 can also be communicatively coupled to the respective pitch adjustment mechanisms 32 of the wind turbine 10 (one of which is shown) for controlling and / or changing the pitch angle of the rotor blades 22 relative to the wind direction 28. For example, the turbine controller 26 can be configured to transmit control signals / commands to the respective pitch adjustment mechanisms 32 such that one or more actuators (not shown) of the pitch adjustment mechanism 32 can be used to rotate the blades 22 relative to the hub 20.

[0089] Specifically, controller 26 can be used to execute such a method, and can further control the torque adjustment of generator 24, the yaw adjustment of wind turbine 10, and / or the pitch adjustment of rotor blades 22 based on such a method as discussed herein. Now refer to Figure 3 The illustration is a block diagram of one embodiment of suitable components that may be included within a turbine controller 26 according to aspects of this subject matter. As shown, controller 26 may include one or more processors 60 and associated memory devices 62, configured to perform various computer-implemented functions (e.g., performing the methods, steps, calculations, etc. disclosed herein). Additionally, controller 26 may include a communication module 64 to facilitate communication between controller 26 and various components of the wind turbine 10. For example, communication module 64 may serve as an interface to allow turbine controller 26 to transmit control signals to various pitch adjustment mechanisms 32 for controlling the pitch angle of rotor blades 22. Furthermore, communication module 64 may include a sensor interface 66 (e.g., one or more analog-to-digital converters) to allow input signals transmitted from, for example, various sensors to be converted into signals that can be understood and processed by processor 60.

[0090] Now for reference Figure 4 The illustration shows an exemplary electric power system 100 according to an exemplary embodiment of the present disclosure, which in this embodiment is a doubly fed asynchronous generator (DFAG) wind turbine system. In the exemplary system 100, as discussed above, the wind turbine 10 includes an optional gearbox 44, which is then coupled to a generator 24. According to aspects of the present disclosure, the generator 24 is a doubly fed asynchronous generator (DFAG) 24 having a generator stator 25 and a generator rotor 27. However, it should be understood that the present disclosure is not limited to the DFAG system 100 and DFAG 24, but rather any suitable system and generator (including, for example, a full power conversion system and generator) is within the scope and spirit of the present disclosure.

[0091] DFAG 24 is typically connected to stator bus 122 and power converter 130 via rotor bus 124. Stator bus 122 provides multiphase power (e.g., three-phase power) output from the stator of DFAG 24, and rotor bus 124 provides multiphase power (e.g., three-phase power) output from the rotor of DFAG 24. Referring to power converter 130, DFAG 24 is connected to rotor-side converter 132 via rotor bus 124. Rotor-side converter 132 is connected to line-side converter 134, which in turn is connected to line-side bus 138.

[0092] Power converter 130 may include one or more rotor-side switching elements 192 (which may be components of rotor-side converter 132) and one or more line-side switching elements 194 (which may be components of line-side converter 134). Switching elements 192 for multiple phases of rotor-side converter 132 may be included in the bridge of rotor-side converter 132, and switching elements 194 for multiple phases of line-side converter 134 may be included in the bridge of line-side converter 134. In some embodiments, for example, switching elements 192, 194 may be IGBTs. For example, in an exemplary configuration, rotor-side converter 132 and line-side converter 134 are configured for normal operating mode in a three-phase pulse-width modulation (PWM) arrangement using insulated-gate bipolar transistors (IGBTs) as switching devices. Other suitable switching devices may be used, such as insulated-gate commutated thyristors, MOSFETs, bipolar transistors, silicon controlled rectifiers, or other suitable switching devices. Rotor-side converter 132 and line-side converter 134 can be connected via DC link 135, with DC link capacitor 136 spanning DC link 135.

[0093] Power converter 130 can be communicatively coupled to controller 26 to control the operation of rotor-side converter 132 and line-side converter 134. For example, controller 26 can send control commands to rotor-side converter 132 and line-side converter 134 to control the modulation of switching elements (such as IGBTs) used in power converter 130 to provide desired active and reactive power output.

[0094] As shown in the figure, system 100 includes transformer 160, which connects wind turbine system 100 to power grid 180. Figure 4 The transformer 160 is a three-winding transformer, comprising a high-voltage (e.g., greater than 12 kVAC) primary winding 162 connected to the power grid, a medium-voltage (e.g., 6 kVAC) secondary winding 164 connected to the stator bus 122, and a low-voltage (e.g., 575 VAC, 690 VAC, etc.) auxiliary winding 166 connected to the line bus 138. It should be understood that the transformer 160 may be a three-winding transformer (as shown), or alternatively, a two-winding transformer having only a primary winding 162 and a secondary winding 164; a four-winding transformer having a primary winding 162, a secondary winding 164, an auxiliary winding 166, and additional auxiliary windings; or any other suitable number of windings.

[0095] Auxiliary power feeder 170 is connected to the output of power converter 130. Auxiliary power feeder 170 serves as a power source for various components of wind turbine system 100. For example, auxiliary power feeder 170 can provide power to the fan, pump, motor, and other suitable components of wind turbine system 100.

[0096] In operation, the power generated at DFAG 24 by rotating rotor 106 is supplied to grid 180 via a dual path. The dual path is defined by stator bus 122 and rotor bus 124. On the rotor bus 124 side, sinusoidal multiphase (e.g., three-phase) alternating current (AC) power is supplied to power converter 130. Rotor-side power converter 132 converts the AC power supplied from rotor bus 124 into direct current (DC) power and supplies the DC power to DC link 135. Switching devices (e.g., IGBTs) used in the parallel bridge circuit of rotor-side power converter 132 can be modulated to convert the AC power supplied from rotor bus 124 into DC power suitable for DC link 135.

[0097] Line-side converter 134 converts DC power on DC link 135 into AC power at a frequency suitable for the power grid 180. Specifically, switching devices (e.g., IGBTs) used in the bridge circuit of line-side power converter 134 can be modulated to convert DC power on DC link 135 into AC power on line-side bus 138. Power from power converter 130 can be supplied to the power grid 180 via auxiliary winding 166 of transformer 160.

[0098] The power converter 130 may receive control signals from, for example, the controller 26. These control signals may be based, in particular, on sensing conditions or operating characteristics of the wind turbine system 100. For example, the control signal may be based on a sensed voltage associated with the transformer 160 (as determined by voltage sensor 144). As another example, the control signal may be based on a sensed voltage associated with the auxiliary power feed device 170 (as determined by voltage sensor 146).

[0099] Typically, control signals provide control over the operation of the power converter 130. For example, feedback in the form of sensed speed in DFAG 24 can be used to control the conversion of output power from the rotor bus 156 to maintain an appropriate and balanced multiphase (e.g., three-phase) power supply. Other feedback from other sensors (including, for example, stator and rotor bus voltage and current feedback) can also be used by the controller 26 to control the power converter 130. Using various forms of feedback information, switching control signals (e.g., gating timing commands for IGBTs), stator synchronization control signals, and circuit breaker signals can be generated.

[0100] On the stator bus 122 side, sinusoidal multiphase (e.g., three-phase) alternating current (AC) power is supplied from the stator of generator 120 to stator bus 122, and from stator bus 122 to transformer 160, and specifically to the secondary winding 164 of transformer 160. Various circuit breakers, fuses, contactors, and other devices (such as grid circuit breaker 158, stator bus circuit breaker 156, switch 154, and line bus circuit breaker 152) may be included in system 100 to connect or disconnect the corresponding bus (e.g., when excessive current could damage components of wind turbine system 100 or for other operational considerations). Additional protective components may also be included in wind turbine system 100.

[0101] Still referencing Figure 4 A dynamic brake 180 may be disposed in the power converter 130 between the rotor-side converter 132 and the line-side converter 134. The dynamic brake 180 absorbs energy from the converter 130 when it is gated open. For example, in the exemplary embodiment shown, the dynamic brake 180 may include a resistor 182 connected in series with a switch 184, which may be, for example, an IGBT.

[0102] Now for reference Figure 4 and Figure 5 This disclosure further relates to methods for operating an electric power system 100. In some embodiments, a controller 26 is configured to perform such operations. In particular, as shown at 310, method 300 may include monitoring current magnitude values ​​312 in one or more rotor-side converters 132 or one or more line-side converters 134.

[0103] Such step 310 can utilize the current magnitude value 312 in all rotor-side converters 132 or line-side converters 134 of the power converter 130. In some embodiments, the current magnitude value 312 may correspond to the vector magnitude value of the instantaneous current (in a single time) of all phases in the system at the bridge of one or more rotor-side converters 132 or line-side converters 134. For example, in some embodiments for a single rotor-side converter 132 or line-side converter 134, the current magnitude value 312 may be the sum of the squares of the instantaneous currents in the respective phases at the bridge, such as as follows:

[0104] .

[0105] In other embodiments, the current value 312 may be the square root of the sum of the squares of the instantaneous currents in each phase of the bridge, such as the following:

[0106] .

[0107] In other embodiments, the current value 312 may be the square root of two-thirds multiplied by the square root of the sum of the squares of the instantaneous currents in each phase of the bridge, such as as follows:

[0108] .

[0109] When the power converter 130 includes a plurality of rotor-side converters 132 or line-side converters 134, the current magnitude corresponds to the sum of the current magnitudes in the respective bridges of each of the plurality of rotor-side converters 132 or line-side converters 134, such as as follows:

[0110]

[0111] or

[0112]

[0113] or

[0114]

[0115] or

[0116] .

[0117] It should be understood that other suitable variations of the above equation may be used for purposes such as ease of programming and computation.

[0118] Therefore, as shown, method 300 may further include, for example, step 320: comparing a current quantity value 312 in one or more rotor-side converters 132 or line-side converters 134 with a primary predetermined threshold (e.g., 322). In some embodiments, the primary predetermined threshold 322 may correspond to a predetermined threshold indicating that a fault event has occurred. Such a threshold may be predetermined and therefore programmed into controller 26, for example.

[0119] Still referencing Figure 5 As shown at 302, method 300 also includes monitoring voltage values ​​in generator 24 of the electric power system 100. For example, as shown, the alternating current (AC) voltage value (Vac) can be detected from generator rotor 27.

[0120] Therefore, as shown at 304, method 300 may further include comparing a voltage quantity value (e.g., Vmag) in generator stator 27 with a voltage threshold 306. For example, in an embodiment, the voltage threshold may be set to a voltage level lower than the voltage level seen during a grid fault. For example, in such an embodiment, the voltage threshold may range from approximately 0.1 pu to approximately 0.5 pu.

[0121] Therefore, as shown at 330, method 300 includes disabling the bridge switches of one or more rotor-side converters 132 or line-side converters 134 when not only the current magnitude (e.g., Imag) increases above a primary current threshold (e.g., Ithres 322), but also the voltage magnitude (e.g., Vmag) decreases below a voltage threshold (e.g., Vthres 306). Specifically, in embodiments, method 300 may also include disabling the bridge switches of one or more rotor-side converters 132 or line-side converters 134 when the current magnitude increases above a primary current threshold while the voltage magnitude decreases below a voltage threshold. Thus, disabling the bridge switches of one or more rotor-side converters 132 or line-side converters 134 is configured to provide rapid dissipation of excess energy stored in the power system 100.

[0122] When the bridge switch is disabled for one or more rotor-side converters 132, no switching of any of the switching elements 192 in any of the rotor-side converters 132 occurs. Similarly, when the bridge switch is disabled for one or more line-side converters 134, no switching of any of the switching elements 194 in any of the line-side converters 134 occurs. Furthermore, in exemplary embodiments, such switching elements 192 or 194 are disabled in the gated open position. Therefore, in these embodiments, when the bridge switch is disabled for one or more rotor-side converters 132, all switching elements 192 in all or more rotor-side converters 132 are disabled in the gated open position. Likewise, in these embodiments, when the bridge switch is disabled for one or more line-side converters 134, all switching elements 194 in all or more line-side converters 134 are disabled in the gated open position.

[0123] As discussed, the power converter 130 may also include a dynamic brake 180. Therefore, in some exemplary embodiments, the dynamic brake 180 may be gated open after a disable occurs according to step 330 and while such a disable state is occurring. Furthermore, in some exemplary embodiments, and after the dynamic brake 180 is gated open, the dynamic brake 180 may be gated closed after a disable occurs according to step 330 and while such a disable state is occurring, or after an enable occurs (as discussed herein).

[0124] Still referencing Figure 5Method 300 may further include, for example, step 340: comparing a current quantity value 312 in one or more rotor-side converters 132 or line-side converters 134 with a secondary predetermined threshold 342. This step 340 occurs after step 330 and is therefore based on the current quantity value 312 at a time after such step 330 has occurred. The secondary predetermined threshold 342 may correspond to a predetermined threshold indicating that a fault event has ended or that the risk of enabling a switch in the power converter 130 has been appropriately reduced after the fault event has occurred. Such a threshold may be predetermined and therefore, for example, programmed into the controller 26.

[0125] In some exemplary embodiments, the secondary predetermined threshold 342 differs from the primary predetermined threshold. Alternatively, the secondary predetermined threshold 342 may be the same as the primary predetermined threshold 322.

[0126] Furthermore, in another embodiment, method 300 may further include, for example, step 350: when the current value 312 drops below and is therefore less than the secondary predetermined threshold 342, activating a bridge switch of one or more rotor-side converters 132 or line-side converters 134. When the bridge switch is activated for the rotor-side converter(s) 132, the switching of the switching elements 192 in one or more rotor-side converters 132 occurs again, similar to the switching that occurred before step 330. When the bridge switch is activated for the line-side converter(s) 134, the switching of the switching elements 194 in one or more line-side converters 134 occurs again, similar to the switching that occurred before step 330.

[0127] Now for reference Figure 6 and Figure 7 This disclosure is particularly suitable for series-compensated transmission systems. As used herein, a series-compensated transmission system generally refers to a system that improves power transfer capability by connecting a capacitor in series with the transmission line. In other words, in series compensation, a negative impedance is inserted in series with the transmission line to reduce the system impedance. For example, as... Figure 6The diagram shown is a simplified schematic of one embodiment of a series-compensated transmission system 400. At either end, a representative Thevenin equivalent circuit of a large interconnect system can be provided; therefore, the diagram is intended to represent only the two transmission lines 402, 404 departing from the interconnection point 406 of the inverter-based resource (IBR) 408. Specifically, as shown, transmission line 404 is series-compensated, meaning it includes at least one series capacitor 410. It should be understood that the power system 100 described herein may be the inverter-based resource (IBR) 408. Furthermore, the series-compensated transmission system 400 may include multiple power systems, which are also referred to herein as inverter-based resources (IBRs).

[0128] therefore, Figure 7 The diagram is for operation. Figure 6 The flowchart illustrates one embodiment of the method 500 for a series-compensated transmission system 400. Generally, the method 500 described herein is applied to the operation of the DFAG wind turbine power system 100 described herein. However, it should be recognized that the disclosed method 500 can be implemented using any other suitable power system (such as a solar power system, a hydroelectric power system, an energy storage power system, or a combination thereof) configured to supply power for an application to a load (such as a power grid). Furthermore, for illustrative and descriptive purposes, Figure 7 The steps are described in a specific order. Those skilled in the art will understand, using the disclosure provided herein, that the various steps of any method disclosed herein may be adapted, omitted, rearranged, or extended in a variety of ways without departing from the scope of this disclosure.

[0129] As shown at 502, method 500 includes monitoring voltage and current values ​​at IBR 408 via IBR 408. As shown at 504, method 500 includes determining whether the current or voltage value exceeds the device ratings for IBR 408. If so, as shown at 506, method 500 includes using both the current and voltage values ​​to determine whether the type of high-current event is due to energy dissipated from series capacitor(s) 410. Therefore, as shown at 508, method 500 includes implementing control actions based on the type of high-current event. For example, as shown, the type of high-current event may include, for example, fault clearing 512 or grid fault 510 in the series compensated transmission system 400.

[0130] In a particular embodiment, dissipated energy may be received from series capacitor 410. In such an embodiment, such dissipated energy may indicate fault clearing occurring in system 400. Therefore, as shown at 514, control actions may include preventing or avoiding the disabling of switching of one or more rotor-side converters 132 or line-side converters 134 based on inverter resources. In another embodiment, as shown at 516, control actions may further include maintaining current and voltage values ​​within device ratings based on inverter resources 408. In such an embodiment, as shown at 518, control actions may further include damping series resonances from the series compensation system 400 that cause oscillations in voltage and current values.

[0131] In an alternative embodiment, for example, energy dissipation may be received from a power grid due to a grid failure. In such an embodiment, as shown at 520, control actions may include disabling the switching of one or more rotor-side converters 132 or line-side converters 134 when the current value increases above a primary current threshold and the voltage value decreases below a voltage threshold.

[0132] This written description uses examples to disclose the invention (including the best mode) and also enables any person skilled in the art to practice the invention (including making and using any apparatus or system, and performing any incorporated methods). The patentability of the invention is defined by the claims and may include other examples that would occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that are not different from the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims.

[0133] Further aspects of the invention are provided by the subject matter of the following provisions:

[0134] Clause 1. A method for operating an inverter-based resource, the inverter-based resource including a power converter having a plurality of switching elements, the method comprising:

[0135] Monitor the current levels in inverter-based resources;

[0136] Monitor voltage levels in inverter-based resources;

[0137] Compare the current values ​​in the inverter-based resources with the primary current threshold;

[0138] Compare the voltage values ​​in the inverter-based resources with voltage thresholds; and...

[0139] When the current value increases above the primary current threshold and the voltage value decreases below the voltage threshold, the switching of the power converter's switching elements is disabled to bypass the power converter's switching elements until excess energy in the inverter's resources is dissipated.

[0140] Clause 2. The method according to Clause 1 further includes disabling the switching of the switching element of the power converter when the current value increases above the primary current threshold and the voltage value decreases below the voltage threshold.

[0141] Clause 3. The method according to any one of the preceding claims, wherein the inverter-based resources include a doubly fed asynchronous generator (DFAG).

[0142] Clause 4. The method according to Clause 3, wherein the DFAG includes a generator rotor and a generator stator, and the method further includes detecting a voltage quantity value in the generator stator.

[0143] Clause 5. The method according to any of the preceding claims, wherein the voltage threshold is set to the voltage level observed for a nearby grid fault, the voltage threshold ranging from about 0.1 pu to about 0.5 pu.

[0144] Clause 6. The method according to any of the preceding claims, wherein, by requiring not only an increase in current value above a primary current threshold but also a decrease in voltage value below a voltage threshold before disabling the switch, the method distinguishes between high current caused by the discharge of energy stored within the inverter-based resource and high current caused by the discharge of energy from sources outside the inverter-based resource.

[0145] Clause 7. The method according to any one of the preceding claims further comprises:

[0146] After a disable occurs, the current value in the power converter is compared with the secondary current threshold; and

[0147] When the current value is less than the secondary current threshold, the switching element of the power converter is activated.

[0148] Clause 8. The method of Clause 7, wherein the secondary current threshold is different from the primary current threshold.

[0149] Clause 9. The method according to any of the preceding claims, wherein the power converter further includes a DC link and a dynamic brake, and wherein the dynamic brake is gated open after a disable occurs.

[0150] Clause 10. The method according to any of the preceding claims, wherein the inverter-based resources include at least one of a full-conversion wind turbine power system, a solar power system, or an energy storage system.

[0151] Clause 11. A method for operating inverter-based resources connected to a series-compensated transmission system, the series-compensated transmission system having at least one series capacitor, the method comprising:

[0152] Monitor voltage and current values ​​at inverter-based resources;

[0153] When at least one of the current or voltage values ​​exceeds the device's rated value, both the current and voltage values ​​are used to determine whether the high-current event is due to energy dissipated from at least one series capacitor; and

[0154] Control actions are implemented based on the type of high-current event.

[0155] Clause 12. The method according to Clause 11, wherein the type of high current event includes at least one of fault clearing in a series-compensated transmission system or a grid fault.

[0156] Clause 13. The method according to Clauses 11-12, wherein dissipated energy is received from a series capacitor.

[0157] Clause 14. The method according to Clause 13, wherein implementing control actions based on the type of high-current event occurring in the inverter-based resources when dissipated energy is received from the series capacitor, further includes:

[0158] By using inverter-based resources, the power converter's switching on / off can be prevented from being disabled.

[0159] Clause 15. The method according to Clause 13, wherein implementing control actions based on the type of high-current event occurring in the inverter-based resources when dissipated energy is received from the series capacitor, further includes:

[0160] By utilizing inverter-based resources, current and voltage values ​​are maintained within the device ratings based on inverter-based resources.

[0161] Clause 16. The method according to Clause 13, wherein implementing control actions based on the type of high-current event occurring in the inverter-based resources when dissipated energy is received from the series capacitor, further includes:

[0162] The damping comes from the series resonance of the series compensation system, which causes oscillations in voltage and current values.

[0163] Clause 17. The method according to Clauses 11-16, wherein dissipated energy is received from a power grid.

[0164] Clause 18. The method according to Clause 17, wherein implementing control actions based on the type of high-current event occurring in the inverter-based resources when dissipated energy is received from the power grid, further includes:

[0165] The power converter is disabled when the current increases above the primary current threshold and the voltage decreases below the voltage threshold.

[0166] Clause 19. A wind power system connected to a series-compensated transmission system, the series-compensated transmission system having at least one series capacitor, the wind power system comprising:

[0167] A doubly-fed asynchronous generator, which includes a generator rotor and a generator stator;

[0168] A power converter coupled to a generator rotor, the power converter including a rotor-side converter and a line-side converter, the rotor-side converter or the line-side converter including a plurality of switching elements defining a bridge;

[0169] The controller, communicatively connected to the power converter, is configured to perform multiple operations, including:

[0170] Receive voltage and current feedback from the wind turbine power system;

[0171] The voltage and current values ​​at the wind power system are determined based on voltage and current feedback;

[0172] When at least one of the current or voltage values ​​exceeds the device's rated value, both the current and voltage values ​​are used to determine the type of high-current event that has occurred; and

[0173] Bridge switches can be selected between disabling or enabling rotor-side converters or line-side converters based on the type of high-current event.

[0174] Clause 20. A wind power system pursuant to Clause 19, wherein the type of high current event includes at least one of a grid fault in the power grid or a fault clearing in the wind power system.

Claims

1. A method for operating an inverter-based resource comprising a power converter having a plurality of switching elements, the method comprising: monitoring a current magnitude value in the inverter-based resource; monitoring a voltage magnitude value in the inverter-based resource; comparing the current magnitude value in the inverter-based resource to a primary current threshold; comparing the voltage magnitude value in the inverter-based resource to a voltage threshold; and, when the current magnitude value increases above the primary current threshold and the voltage magnitude value decreases below the voltage threshold, disabling switching of the switching elements of the power converter to bypass the switching elements of the power converter until excess energy in the inverter-based resource is dissipated, wherein the method distinguishes between high current caused by a discharge of energy stored within the inverter-based resource and high current caused by a discharge of energy from a source external to the inverter-based resource by requiring not only that the current magnitude value increase above the primary current threshold but also that the voltage magnitude value decrease below the voltage threshold before disabling switching. the method further comprising disabling switching of the switching elements of the power converter when the current magnitude value increases above the primary current threshold while the voltage magnitude value decreases below the voltage threshold.

2. The method of claim 1, wherein, the inverter-based resource comprises a doubly-fed asynchronous generator (DFAG).

3. The method of claim 1, wherein, the DFAG comprises a generator rotor and a generator stator, the method further comprising detecting the voltage magnitude value in the generator stator.

4. The method of claim 3, wherein, the voltage threshold is set to a voltage level observed for a nearby grid fault, the voltage threshold ranging from 0.1 pu to 0.5 pu.

5. The method of claim 1, wherein, the method further comprising:

6. The method of claim 1, wherein, after disabling occurs, comparing the current magnitude value in the power converter to a secondary current threshold; and when the current magnitude value is less than the secondary current threshold, enabling switching of the switching elements of the power converter. the secondary current threshold is different than the primary current threshold.

7. The method of claim 6, wherein, the power converter further comprises a DC link and a dynamic brake, and wherein the dynamic brake is gated on after disabling occurs.

8. The method of claim 1, wherein, the inverter-based resource comprises at least one of a full-conversion wind turbine power system, a solar power system, or an energy storage system.

9. The method of claim 1, wherein, 10. A method for operating an inverter-based resource connected to a series-compensated transmission system having at least one series capacitor, the method comprising: monitoring, via the inverter-based resource, a voltage magnitude value and a current magnitude value at the inverter-based resource; ​ using both the current magnitude and the voltage magnitude to determine whether a type of a high current event occurring is due to energy dissipated from the at least one series capacitor to distinguish between a high current caused by a discharge of energy stored within the inverter-based resource and a high current caused by a discharge of energy from a source external to the inverter-based resource; and, implementing a control action based on the type of the high current event.

11. The method of claim 10, wherein, the type of the high current event includes at least one of a fault clearing in the series compensated transmission system or a grid fault.

12. The method of claim 10, wherein, the dissipated energy is received from the series capacitor.

13. The method of claim 12, wherein, implementing the control action based on the type of the high current event occurring in the inverter-based resource when the dissipated energy is received from the series capacitor further includes: preventing, via the inverter-based resource, a disabling of a switch of a power converter of the inverter-based resource.

14. The method of claim 12, wherein, implementing the control action based on the type of the high current event occurring in the inverter-based resource when the dissipated energy is received from the series capacitor further includes: maintaining, via the inverter-based resource, the current magnitude and the voltage magnitude within a device rating of the inverter-based resource.

15. The method of claim 12, wherein, implementing the control action based on the type of the high current event occurring in the inverter-based resource when the dissipated energy is received from the series capacitor further includes: damping a series resonance from the series compensated transmission system that causes oscillations on the voltage magnitude and the current magnitude.

16. The method of claim 10, wherein, the dissipated energy is received from a power grid.

17. The method of claim 16, wherein, implementing the control action based on the type of the high current event occurring in the inverter-based resource when the dissipated energy is received from the power grid further includes: disabling a switch of a power converter of the inverter-based resource when the current magnitude increases above a primary current threshold and the voltage magnitude decreases below a voltage threshold.

18. A wind power system connected to a series compensated transmission system having at least one series capacitor, the wind power system comprising: a doubly-fed asynchronous generator including a generator rotor and a generator stator; a power converter coupled to the generator rotor, the power converter including a rotor-side converter and a line-side converter, the rotor-side converter or the line-side converter including a plurality of switching elements defining an electrical bridge; a controller communicatively coupled to the power converter, the controller configured to perform a plurality of operations, the plurality of operations including: receiving voltage and current feedback from the wind power system; determining a voltage magnitude and a current magnitude at the wind power system based on the voltage and current feedback; when at least one of the current magnitude or the voltage magnitude exceeds a device rating, using both the current magnitude and the voltage magnitude to determine a type of high current event occurring to distinguish between a high current caused by a discharge of energy stored within the wind power system and a high current caused by a discharge of energy from a source external to the wind power system; and, selecting between disabling or enabling the bridge switches of the rotor-side converter or the line-side converter based on the type of high current event.

19. The wind power system of claim 18, wherein, the type of high current event includes at least one of a grid fault in a power grid or a fault clearing in the wind power system.

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