System and method for adaptive power system stabilizer (PSS)

Abstract

A power generation system includes an adaptive power system stabilizer (PSS). The adaptive PSS includes a first estimator configured to receive as input a plurality of sensor measurements and output a derived infinite bus (IB) value. The adaptive PSS also includes a second estimator disposed downstream of the first estimator and configured to receive the derived IB value as an input and to output a derived generator parameter, where the adaptive PSS is configured to provide stability of the generator using the derived generator parameter.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of French application No. 2211106, filed on October 26, 2022, entitled “SYSTEMS AND METHODS FOR ANADAPTIVE POWER SYSTEM STABILIZER (PSS)”, the entire text of which is incorporated herein by reference. Background Art

[0003] The subject matter disclosed herein relates to power system stabilizers, and more particularly to adaptive power system stabilizers.

[0004] Certain power generation systems may include generators and distributed generators, which may be powered by a turbine system, such as, but not limited to, a gas turbine system. The gas turbine system may, for example, provide a motive force suitable for rotating the generator and thereby generating electricity. The turbine system and the generator system may include one or more controllers suitable for providing a variety of control functions, such as control of turbine speed, load, generator voltage, reactive power flow, and overall stability of the power generation system. During operation, the power generation system may be electrically coupled to a power grid, such as a city or municipal power grid. However, under certain operating conditions of the power grid, transient conditions may occur. It would be beneficial to improve the handling of transient conditions by a power system stabilizer (PSS). Summary of the invention

[0005] Some embodiments comparable to the scope of the initially claimed invention are summarized below. These embodiments are not intended to limit the scope of the claimed invention, but these embodiments are intended only to provide a brief overview of possible forms of the invention. In fact, the present invention may include various forms that may be similar or different from the embodiments set forth below.

[0006] In a first embodiment, a power generation system includes an adaptive power system stabilizer (PSS). The adaptive PSS includes a first estimator configured to receive a plurality of sensor measurements as input and output a derived infinite bus (IB) value. The adaptive PSS also includes a second estimator disposed downstream of the first estimator and configured to receive the derived IB value as input and output a derived generator parameter, wherein the adaptive PSS is configured to use the derived generator parameter to provide stability of the generator.

[0007] In a second embodiment, a method includes: obtaining a plurality of sensor measurements via a sensor network; and deriving an infinite bus (IB) value via a first estimator; wherein the first estimator is configured to output the IB value using the plurality of sensor measurements as input. The method also includes: deriving a derived generator parameter via a second estimator disposed downstream of the first estimator, wherein the second estimator is configured to output the derived generator parameter using the IB value and the plurality of sensor measurements as input. The method also includes: stabilizing the generator via an adaptive power system stabilizer (PSS) based on the derived generator parameter.

[0008] In a third embodiment, a non-transitory computer readable medium having computer executable code stored thereon, the code including instructions for obtaining a plurality of sensor measurements via a sensor network; and deriving an infinity bus (IB) value via a first estimator; wherein the first estimator is configured to output the IB value using the plurality of sensor measurements as input. The code also includes instructions for deriving a derived generator parameter via a second estimator disposed downstream of the first estimator, wherein the second estimator is configured to output the derived generator parameter using the IB value as input. The code also includes instructions for stabilizing a generator via an adaptive power system stabilizer (PSS) based on the derived generator parameter. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] These and other features, aspects and advantages of the present invention will be better understood when the following detailed description is read with reference to the accompanying drawings, in which like characters refer to like parts throughout the several views, and in which:

[0010] Figure 1 is a block diagram of one embodiment of a power generation system having an adaptive power system stabilizer;

[0011] Figure 2 is a block diagram illustrating one embodiment of a first estimator that may be coupled to a second estimator, wherein the first estimator and / or the second estimator may include Figure 1 in the adaptive power system stabilizer of;

[0012] Figure 3 is a block diagram showing further details of one embodiment of a second estimator with a switchable model; and

[0013] Figure 4 It is shown that it is suitable for application Figure 1 A flow chart of one embodiment of a process of an adaptive power system stabilizer. DETAILED DESCRIPTION

[0014] One or more specific embodiments of the present invention will be described below. In order to provide a concise description of these embodiments, all features of the actual implementation may not be described in the specification. It should be understood that in the development of any such actual implementation, as in any engineering or design project, many implementation-specific decisions must be made to achieve the developer's specific goals, such as complying with system-related and business-related constraints, which may vary from implementation to implementation. In addition, it should be understood that such development work may be complex and time-consuming, but it is still a routine task of design, production and manufacturing for ordinary technicians who benefit from this disclosure.

[0015] When introducing elements of various embodiments of the present invention, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of the elements. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements.

[0016] The present embodiment relates to a system and method for power system stabilization of a generator that can be connected to a prime mover, such as, but not limited to, a gas turbine system, a steam turbine system, a hydroelectric turbine system, a wind turbine system, a nuclear turbine system, or any combination thereof. Specifically, an adaptive power system stabilizer (PSS) system is provided to continuously and adaptively determine the application of PSS setpoints based on a cascade model (e.g., a cascade model) to suppress one or more of a plurality of oscillation frequency ranges (e.g., a joint frequency range, a local frequency range, an in-plant frequency range, etc.). For example, power generated by renewable energy sources (e.g., wind, solar, etc.) can cause frequency changes in the power grid (e.g., transient conditions). Therefore, when the source of the transient condition causes a specific transient change (e.g., above or below a threshold), there may be less synchronous inertia, and an increase in the rate of change of the frequency condition may cause the power generation system to react. Similarly, the power grid can become more dynamic by using specific renewable energy technologies (e.g., solar power plants, wind power plants, hydroelectric power plants), which may change the power generation during operation due to cloud patterns, wind conditions, rainfall, etc.

[0017] The techniques described herein include the use of a set of cascaded estimators, wherein the first estimator in the cascaded set can now derive an infinite bus value (such as a voltage value of the infinite bus) and an external reactance. In fact, the first estimator can now take into account changes in the infinite bus caused by, for example, a renewable energy generation system, rather than treating the infinite bus as a constant. The derived infinite bus value can then be used as an input to a second estimator downstream of the first estimator. The second switchable estimator can model the details of a machine (e.g., a generator) and use specific internal variables or parameters of the first estimator. The second estimator may include a switching logic component that switches between various models, as further described below. The adaptive PSS can then use the output of the second estimator to improve power generation, for example, by adjusting specific signals sent to an automatic voltage regulator (AVR) that are useful in suppressing or eliminating system oscillations via the AVR. Therefore, even when renewable energy sources are connected to the grid, the techniques described herein can provide enhanced stability and improved power output.

[0018] As used herein, "power system stability" may refer to at least the ability of a power system and associated components (e.g., a power grid, a generator, a turbine, etc.) to transition from, for example, a steady-state operating point (e.g., a nominal operating point) to, for example, one or more other operating points (e.g., transient and / or dynamic operating points) after a disturbance, interference, or other undesirable impact on the power system. In addition, as used herein, "suppression," "damping," and / or "damped oscillations" may refer to the act or result of an oscillation whose amplitude decreases over time. Similarly, "new operating parameters," "new states," or "new operating conditions" may refer to operating points and / or operating conditions to which a power system and associated components (e.g., a power grid, a generator, a turbine, etc.) may transition periodically and / or non-periodically during operation, for example, after a disturbance, interference, or other undesirable impact on the power system.

[0019] In view of the foregoing, an embodiment of a power generation system (such as Figure 1The exemplary power generation system 10 shown may be useful. The power generation system 10 may include various subsystems, such as a turbine 12, a generator 14, and an exciter 16. The turbine 12 (e.g., a gas turbine, a steam turbine, a hydro turbine, etc.) may be coupled to the generator 14 via a shaft 13 and controlled via a turbine controller 15. The generator 14 may in turn be communicatively coupled to a generator exciter 16. The exciter 16 may provide direct current (DC) to the field winding 22 of the generator 14. In particular, the exciter 16 may provide a DC field current (e.g., a current used by the field winding 22 of the generator 14 and / or other synchronous machines to establish a magnetic field for operation) to excite the magnetic field of the generator 14. For example, the exciter 16 may be a static (e.g., power electronics) or a rotating (e.g., brush and / or brushless) exciter. In other embodiments, the exciter 16 may be bypassed, and the power output may directly power the field winding 22 of the generator 14. As also shown, the output terminals of generator 14 may be coupled to a large-scale utility grid 26 via alternating current (AC) lines 28. Alternatively, the output terminals of generator 14 may be coupled to a small industrial power plant.

[0020] The power generation system 10 may also include an excitation system 24 that may provide various control parameters to each of the generator 14 and / or the exciter 16, for example, based on measured parameters and / or indications of measured parameters received at one or more inputs to the excitation system 24. In certain embodiments, the excitation system 24 may function as an excitation control for the generator 14 and the exciter 16. The excitation system 24 may include one or more controllers 32 and one or more power converters 34. As generally shown, the controller 32 may include one or more processors 36 and a memory 38 that may be used together to support an operating system, software applications, systems, etc. that may be used to implement the techniques described herein.

[0021] The power converter 34 may include a subsystem of integrated power electronic switching devices, such as silicon controlled rectifiers (SCRs), thyristors, insulated gate bipolar transistors (IGBTs), etc., which receive alternating current (AC) power, DC power, or a combination thereof from a source such as, for example, the power grid 26. The excitation system 24 may receive this power via a bus 29 and may provide power, control, and monitoring of the field winding 30 of the exciter 16 based thereon. Thus, the excitation system 24 and the exciter 16 may work together to drive the generator 14 according to a desired output (e.g., grid voltage, power factor, load frequency, torque, speed, acceleration, etc.). For example, in one embodiment, the excitation system 24 may be an excitation controller system, such as the EX2100e available from General Electric Co. of Schenectady, New York.TM Excitation control regulator system.

[0022] In certain embodiments, the grid 26, and thus the turbine 12 and the generator 14, may be susceptible to certain disturbances due to, for example, a transient loss of power generation by the generator 14, a power line 28 switching, a load change on the grid 26, an electrical fault on the grid 26, etc. Such disturbances may cause the operating frequency of the turbine 12 and / or the generator 14 (e.g., approximately 50 Hz for most countries in Europe and Asia and approximately 60 Hz for countries in North America) to experience undesirable oscillations, which may cause transient and / or dynamic instabilities in the system 10. Such transient and / or dynamic instabilities may cause the generator 14, as well as the turbine 12 and the exciter 16, to transition from a steady-state operating point to a transient and / or dynamic operating point. Specifically, frequency deviations on the grid 26 may cause the generator 14 rotor angle to swing (e.g., power angle oscillations) throughout the power system 10. In addition, because a conventional power system stabilizer (CPSS) system (e.g., a system for suppressing rotor angle oscillations of generator 14) is typically configurable based on linear fixed parameters, unlike the adaptive PSS technology described herein, the CPSS system may not be able to effectively suppress rotor angle oscillations of generator 14 over the entire dynamic operating range of generator 14 as desired.

[0023] As will be discussed in further detail below, in certain embodiments, the controller 32 of the excitation system 24 may include an adaptive power system stabilizer (PSS) system (in Figure 2 ), the adaptive power system stabilizer system can be implemented as part of the excitation system 24 to dynamically and adaptively adjust (e.g., dynamically and adaptively dampen) frequency oscillations of, for example, the rotor of the generator 14, and thereby enhance the ability of the system 10 to seamlessly move to transient and / or dynamic operating points or substantially return to a steady-state operating point or undergo a transition to a new steady-state operating point (e.g., derived by the adaptive PSS system) and maintain stable operation at the new steady-state operating point. The adaptive PSS system can be coupled to an automatic voltage regulator (AVR) and use the AVR to, for example, dampen certain oscillations, and is further described below.

[0024] Figure 2is a block diagram of one embodiment of an excitation system 24. More specifically, the excitation system 24 is shown to include an adaptive power system stabilizer (PSS) system 50 and an automatic voltage regulator (AVR) 52. As previously described, the turbine 12 controlled by the turbine controller 15 can generate mechanical power (Pmec) and be used to rotationally turn a rotor included in the generator 14. As generally shown, the controller 15 can include one or more processors 17 and a memory 19, which can be used together to support operating systems, software applications, systems, etc. that can be used to implement the techniques described herein. The rotation of the rotor in the magnetic field can generate electricity, which can then be transmitted through a transformer (X T )54 and line (X L ) 56 transmission. An infinity bus 58 is also shown.

[0025] The infinite bus 58 is traditionally described as a bus whose frequency and voltage remain constant regardless of the amount of load on the infinite bus. For example, a very large number of generators 14 (e.g., synchronous machines) can be connected to the bus so that the bus is considered to have infinite real power and reactive power. Therefore, electrical devices connected to the infinite bus will generally not affect other electrical devices when turned on or off. However, as more and more renewable energy sources (e.g., solar panels, wind turbines, hydro turbines, etc.) are added to the infinite bus, large energy sources (e.g., 1 kW and above) may disrupt other devices that are now online and offline, such as generators 14. Therefore, the techniques described herein model the infinite bus, for example via an estimator, to behave as if there may be actual voltage and / or frequency fluctuations.

[0026] In the depicted embodiment, the first estimator 60 may now include an infinite bus computing system 62 and a single state estimator 64. The estimator 64 may include, but is not limited to, a Kalman filter type estimator. The inputs to the first estimator 60 may include measurements obtained through a sensor network 66. The sensor network 66 may sense generator 14 characteristics such as voltage, amperage, active power, reactive power, slip, frequency, phase angle, noise, etc. The measurements from the sensor network 66 may be provided as inputs to the estimator 60 and the second cascaded estimator 68.

[0027] The first estimator 60 may use a single state estimator 64 to provide an external reactance X EAs output (e.g., state estimate). The infinite bus calculation system 62 can then provide derived infinite bus values, such as infinite bus voltage and / or frequency. In the depicted embodiment, the single state estimator 64 can use specific model parameters, such as process noise covariance (qEK) representing uncertainty in the calculation of the process, sensor noise covariance (rEK) representing noise in the sensor (e.g., sensor network 66).

[0028] The single state estimator 64 can use the relation The generator stator current lst, generator stator voltage Ust and phase angle in (i.e., the angle between the stator voltage and the stator current) as input, where X E is the external reactance provided as output, and IB is the derived X E Infinite bus voltage. lst, Ust and The measurements of may be provided by the sensor network 66 and IB may be calculated by the system 62. Any type of single-state estimator may be used, including but not limited to a conventional Kalman-Bush filter, such as a linear quadratic estimator or an estimator adapted to use the relation Solve for X based on the values ​​of the remaining terms (including historical values) E Other types of estimators.

[0029] The second estimator 68 may use as inputs the mechanical power (Pmec) that may be provided by the turbine controller 15, the generator field voltage (Efd) that may be provided by the excitation system 24, and the IB voltage that may be derived via the infinity bus computing system 62. The second estimator 68 may use certain model parameters, such as the process noise covariance (Q) that represents uncertainty in the calculation of the process EK ), the sensor noise covariance (R ) representing the noise in the sensor (e.g., sensor network 66 ), EK ).

[0030] The second estimator 68 can estimate the internal state of a particular generator 14 (e.g., a synchronous machine), such as the angle δ between the generator electromagnetic field (EMF) and the reference voltage vector; the generator 14 speed ω (e.g., RPM); the generator 14 internal voltage E'; and the magnetic flux ψk in the generator 14. The second estimator 68 can also estimate the external reactance X E As well as some parameters of the machine model itself, as further described below. In fact, the second estimator 68 may also model or otherwise include model parameters in addition to the machine parameters. The second estimator 68 may include a switching logic component 70 that can be used, for example, to switch between certain estimator models, as further described below.

[0031] Also shown is an extended model 72 which can provide specific generator 14 conditions, external reactance X E The extended model 72 may also output measured estimates of power (real power and reactive power), current components, and / or voltage components. The extended model 72 may be a multi-state Kalman filter that embeds a model of the generator 14 connected to the infinite bus 58 as follows:

[0032] Formula 1: X[k+1]=fState(X[k],u[k])+ω[k]

[0033] Formula 2: Z[k+1]=hMeasure(X[k+1],u[k])+v[k]

[0034] where u = [Efd; Pmec; IB] T , ω is the process (model) noise and v is the measurement noise. X[k] represents the system state at time step k as a linear combination of the state X[k-1] at the previous time step, while Z[k] represents the system measurement at time step k. Although the extended Kalman filter is described by equations 1 and 2, it should be understood that it is possible to create a Kalman filter using u = [Efd; Pmec; IB] T Additional estimators that model future state k (e.g. k+1).

[0035] In the depicted embodiment, the extended model is adjustably coupled to a gain system 74. In use, the gain system 75 can compare the measurement results input from the sensor network 66 with the measurement results predicted by the extended model 72 (e.g., via a comparator 76), and adjust the gain to minimize or eliminate the difference. The gain can be a constant (e.g., a positive or negative number), a formula, or a combination thereof. The first estimator 60 and / or the second estimator 68 can be included in the excitation system 24, or can be communicatively and / or operationally coupled to the excitation system 24. The first estimator 60 and / or the second estimator 68 can be provided as software, hardware, or a combination thereof. When implemented as software, the first estimator 60 and / or the second estimator 68 can be executed via the processor 36 and stored in the memory 38.

[0036] The outputs of the second estimator 68, such as a particular generator 14 (e.g., synchronous machine) internal state, such as the angle δ between the EMF and the reference voltage vector; the generator 14 speed ω (e.g., RPM); the generator 14 internal voltage E'; and the magnetic flux ψk in the generator 14; the external reactance X E; the power (in watts) of the generator 14; the current of the generator 14; and / or the voltage of the generator 14 may then be used by the adaptive PSS 50 to, for example, stabilize the generator 14. For example, the adaptive PSS 50 may use the AVR 52 to inject voltage, current, etc. based on the output of the second estimator 68. In this way, a more efficient and adaptive power generation system 10 may be provided.

[0037] Figure 3 is a block diagram of one embodiment of a second estimator 68 including a switching logic component 70 that can be switched via a switching logic trigger 100. Figure 2 Some elements of the second estimator 68 are similar, so the same elements use the same numbers. In the illustrated embodiment, the second estimator 68 may include a plurality of switchable models, such as models 112, 114, and 116. When operation of the power generation system 10 begins, the first model 112 may be used. As described above, the first model 112 may be embedded in the model of the generator 14. For example, the first model 112 may include the above-mentioned formulas 1 and 2, where u = [Efd; Pmec; IB] T , ω is the process (model) noise and v is the measurement noise. The second model 114 may include all of the first model 112 and add one more state variable SV1. SV1 may be, for example, the external reactance X of the grid. E Similarly, the third model 116 may include all of the second model 114, including the state variable SV1, and add another state variable SV2. SV2 may be, for example, a parameter of an extended model of the second estimator 68 that becomes a variable (such as, for example, synchronous reactance).

[0038] In fact, one or more switchable models may include any variables of the extended model 72. Using the internal variables of the extended model 72 in one or more switchable models of the estimator 68 may result in adjustments to the extended model 72 in the estimator 68, thereby improving the predictive power of the output of the estimator 68. It should be understood that more than three switchable models may be used. In fact, 4, 5, 6, 7, 8 or more switchable models may be used to improve the estimation. The state variables (SV) that may be used by the model include the external reactance X of the grid. E , any variables of the first estimator 60 , any parameters of the extended model 72 , and so on.

[0039] The switching logic trigger 100 may switch from one model to the next model (e.g., switching from the first model 112 to the second model 114, then switching from the second model 114 to the third model 116, etc.) by using time, by applying an error threshold, or a combination thereof. When time is used, switching from one model to the next model may occur at fixed intervals, such as between 0.1 and 30 seconds, between 0.5 and 5 hours, etc. When an error threshold is used, the error may be calculated, for example, via the comparator 76 or using other comparisons. For example, the switching logic trigger 100 may calculate the external reactance X calculated by the first estimator 60. E and the external reactance X calculated by the second estimator 68 E A comparison is made, and if the comparison is below a desired amount, a switch to the next model may be made. The techniques described herein may enable the second estimator 68 to make more accurate inferences by applying a switching logic component to select a more complex model.

[0040] Figure 4 is a flow chart of one embodiment of a process 200 suitable for adjusting parameters of the adaptive PSS 50 via the cascaded estimators 60 and 68. The process 200 may be stored as computer instructions in the memory 38 and executed by the processor 36. In the depicted embodiment, the process 200 may obtain (block 202) measurements via the sensor network 66. For example, the sensor network 66 may include one or more sensors disposed in the generator 14, in the transformer 54, on the line 56, and / or in the turbine system 12, such as a voltage sensor, a current sensor, an inductance sensor, a capacitance sensor, a magnetic flux sensor, etc.

[0041] The process 200 may then derive (block 204) certain outputs via the first estimator 60. As previously described, the first estimator 60 may include a single state estimator 64 to provide the external reactance X E As output (e.g., state estimate). The first estimator 60 may also include an infinite bus calculation system 62 that may employ the measurements collected at block 202 to derive the voltage and / or frequency of the infinite bus 58. The process 200 may then determine a model to use using a switching logic component (block 206) included in the second estimate 68. The model to use may be a multi-state model, such as an extended Kalman filter model.

[0042] At startup of the power generation system 10, the first model to be used may be the first model 112. The first model 112 may be an extended Kalman filter that models the generator 14 via equations 1 and 2 above. The process 200 may then derive (block 208) the output of the second estimator 68. The output of the second estimator 68 may include a particular generator 14 (e.g., a synchronous machine) internal state, such as an angle δ between the EMF and a reference voltage vector; a generator 14 speed ω (e.g., RPM); a generator 14 internal voltage E'; and a magnetic flux ψk in the generator 14; an external reactance X E ; the power (in watts) of the generator 14; the current of the generator 14; and / or the voltage of the generator 14. The process 200 may then apply (block 210) the output of the first estimator 60 and / or the second estimator 68 for stabilization. For example, the adaptive PSS 50 may use the AVR 52 to inject voltage, current, etc. based on the output of the first estimator 60 and / or the second estimator 68. In this manner, a more efficient and more adaptive power generation system 10 may be provided.

[0043] Technical effects of the disclosed embodiments include a power generation system with an adaptive power system stabilizer (PSS). The adaptive PSS may use a cascaded set of estimators, where the output of a first estimator is then used as an input to a second estimator. In certain embodiments, the first estimator may include a single-state Kalman filter and an infinite bus computing system. The single-state estimator may be used to derive the external reactance X E and the value for infinite bus. External reactance X E , values ​​for the infinite bus, and variables of the first estimator may be used by the second estimator. The second estimator may include a switching logic component that switches between various models. Each subsequent model may include the previous model plus additional state variables. The switching logic component may be time-based or error threshold-based. By using a cascaded model system with switchable models, the techniques described herein may provide a more accurate and more adaptive PSS that improves the stability of the power generation system.

[0044] As set forth below, the subject matter described above in detail may be defined by one or more clauses.

[0045] A power generation system includes an adaptive power system stabilizer (PSS). The adaptive PSS includes a first estimator, the first estimator being configured to receive a plurality of sensor measurements as input and output a derived infinite bus (IB) value. The adaptive PSS also includes a second estimator, the second estimator being disposed downstream of the first estimator and being configured to receive the derived IB value as input and output a derived generator parameter, wherein the adaptive PSS is configured to provide stability of the generator using the derived generator parameter.

[0046] A system according to any preceding clause, wherein the first estimator comprises a first external reactance X configured to derive E and a single-state estimator of the derived IB value, wherein the second estimator is configured to use the first external reactance X E and the derived IB value as input and the derived includes at least one generator state or a second external reactance X E A set of outputs, and wherein the adaptive PSS is configured to use the set of outputs to provide stability of the generator.

[0047] A system according to any preceding clause, wherein the plurality of sensor measurements comprises a plurality of generator measurements, and wherein the single state estimator is configured to derive the first external reactance X using the plurality of generator measurements. E .

[0048] A system according to any preceding clause, wherein the plurality of generator measurements comprises a generator stator current Ist, a generator stator voltage Ust, a phase angle between the stator voltage and the stator current or a combination thereof.

[0049] A system according to any preceding clause, wherein the single state estimator comprises a state estimator configured to use the relation To solve for the first external reactance X E A single-state Kalman filter, and wherein the IB in the relationship includes a voltage value.

[0050] A system according to any preceding clause, wherein the second estimator comprises a model for modeling an internal state of the generator, the internal state comprising an angle δ between a generator electromagnetic field (EMF) and a reference voltage vector; a generator speed ω; a generator internal voltage E', a magnetic flux ψk in the generator, or a combination thereof.

[0051] A system according to any preceding clause, wherein the adaptive PSS is configured to provide stability of the generator using the derived generator parameters.

[0052] A system according to any preceding clause, wherein the adaptive PSS is included in an excitation system, and wherein the excitation system is configured to generate an electric field via an exciter to operate the generator at a desired output voltage, power factor, frequency, or a combination thereof.

[0053] A system according to any preceding clause, wherein the generator is mechanically coupled to a turbine configured to provide rotational power to the generator.

[0054] A method includes: obtaining a plurality of sensor measurements via a sensor network; and deriving an infinite bus (IB) value via a first estimator; wherein the first estimator is configured to output the IB value using the plurality of sensor measurements as input. The method also includes: deriving a derived generator parameter via a second estimator arranged downstream of the first estimator, wherein the second estimator is configured to output the derived generator parameter using the IB value and the plurality of sensor measurements as input. The method also includes: stabilizing a generator via an adaptive power system stabilizer (PSS) based on the derived generator parameter.

[0055] A method according to any preceding clause, wherein the first estimator comprises a first external reactance X configured to derive E and a single-state estimator of the IB value, wherein the second estimator is configured to use the first external reactance X E and the IB value as input and derives at least one generator state or a second external reactance X E A set of outputs, and wherein the adaptive PSS is configured to use the set of outputs to provide stability of the generator.

[0056] A method according to any preceding clause, wherein the plurality of sensor measurements comprises a plurality of generator measurements, and wherein the single state estimator is configured to derive the first external reactance X using the plurality of generator measurements. E .

[0057] A method according to any preceding clause, wherein the plurality of generator measurements comprises a generator stator current Ist, a generator stator voltage Ust, a phase angle between the stator voltage and the stator current or a combination thereof.

[0058] A method according to any preceding clause, wherein the single state estimator comprises a state estimator configured to use the relation To solve for the first external reactance X EA single-state Kalman filter, and wherein the IB in the relationship includes a voltage value.

[0059] A method according to any preceding clause, wherein the second estimator comprises a model for modeling an internal state of the generator, the internal state comprising an angle δ between a generator electromagnetic field (EMF) and a reference voltage vector; a generator speed ω; a generator internal voltage E', a magnetic flux ψk in the generator, or a combination thereof.

[0060] A non-transitory computer readable medium having computer executable code stored thereon, the code including instructions for the following operations: obtaining a plurality of sensor measurements via a sensor network; and deriving an infinity bus (IB) value via a first estimator; wherein the first estimator is configured to output the IB value using the plurality of sensor measurements as input. The code also includes instructions for the following operations: deriving a derived generator parameter via a second estimator disposed downstream of the first estimator, wherein the second estimator is configured to output the derived generator parameter using the IB value as input. The code also includes instructions for the following operations: stabilizing a generator via an adaptive power system stabilizer (PSS) based on the derived generator parameter.

[0061] The non-transitory computer readable medium of any preceding clause, wherein the first estimator comprises a first external reactance X configured to derive E and a single-state estimator of the IB value, wherein the second estimator is configured to use the first external reactance X E and the IB value as input and derives at least one generator state or a second external reactance X E A set of outputs, and wherein the adaptive PSS is configured to use the set of outputs to provide stability of the generator.

[0062] A non-transitory computer readable medium as described in any preceding clause, wherein the plurality of sensor measurements include a generator stator current Ist, a generator stator voltage Ust, a phase angle between the stator voltage and the stator current or a combination thereof.

[0063] The non-transitory computer-readable medium of any preceding clause, wherein the single-state estimator comprises a state estimator configured to use the relation To solve for the first external reactance X E A single-state Kalman filter, and wherein the IB in the relationship includes a voltage value.

[0064] A non-transitory computer-readable medium as described in any preceding clause, wherein the second estimator includes a model that models an internal state of the generator, the internal state including an angle δ between a generator electromagnetic field (EMF) and a reference voltage vector; a generator speed ω; a generator internal voltage E', a magnetic flux ψk in the generator, or a combination thereof.

[0065] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any device or system and performing any combined method. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that are insubstantially different from the literal language of the claims.

[0066] The technology presented and claimed herein is cited and applied to material objects and specific examples of a practical nature that significantly improve the art and are therefore not abstract, intangible, or purely theoretical. In addition, if any claim appended to the end of this specification contains one or more elements that are designated as "[performs] [a function] ..." or "[performs] the steps of [a function] ...", then those elements should be interpreted under 35 U.S.C. § 112(f). However, for any claim containing an element designated in any other manner, such element should not be interpreted under 35 U.S.C. § 112(f).

Claims

1. A power generation system, the power generation system comprising: An adaptive power system stabilizer (PSS), the adaptive PSS comprising: A first estimator configured to receive a plurality of sensor measurements as inputs and output a derived infinite bus (IB) value; and A second estimator disposed downstream of the first estimator and configured to receive the derived IB value as an input and output derived generator parameters, wherein the adaptive PSS is configured to use the derived generator parameters to provide stability of the generator.

2. The power generation system according to claim 1, wherein the first estimator comprises a single-stage estimator configured to derive a first external reactance X E and the derived IB value, wherein the second estimator is configured to use the first external reactance X E and the derived IB value as inputs and derive a set of outputs including at least one generator state or a second external reactance X E and wherein the adaptive PSS is configured to use the set of outputs to provide stability of the generator.

3. The power generation system according to claim 2, wherein the plurality of sensor measurements include a plurality of generator measurements, and wherein the single state estimator is configured to use the plurality of generator measurements to derive the first external reactance X E .

4. The power generation system according to claim 3, wherein the plurality of generator measurement results include generator stator current lst, generator stator voltage Ust, and the phase angle between the stator voltage and the stator current or a combination thereof.

5. The power generation system according to claim 4, wherein the single state estimator includes a single state Kalman filter configured to solve for the first external reactance X using the relation E , and wherein the IB in the relation includes a voltage value.

6. The power generation system according to claim 5, wherein the second estimator includes a model that models an internal state of the generator, the internal state including an angle δ between a generator electromagnetic field (EMF) and a reference voltage vector; a generator speed ω; an internal voltage E' of the generator, a magnetic flux ψk in the generator, or a combination thereof.

7. The power generation system according to claim 1, wherein the adaptive PSS is configured to use the derived generator parameters to provide stability of the generator.

8. The power generation system according to claim 7, wherein the adaptive PSS is included in an excitation system, and wherein the excitation system is configured to generate an electric field via an exciter to operate the generator at a desired output voltage, power factor, frequency, or a combination thereof.

9. The power generation system according to claim 8, wherein the generator is mechanically coupled to a turbine configured to provide rotational power to the generator.

10. A method, the method comprising: Obtaining a plurality of sensor measurements via a sensor network; Deriving an infinite bus (IB) value via a first estimator; wherein the first estimator is configured to output the IB value using the plurality of sensor measurements as inputs; Deriving derived generator parameters via a second estimator disposed downstream of the first estimator, wherein the second estimator is configured to output the derived generator parameters using the IB value and the plurality of sensor measurements as inputs; and Stabilizing a generator via an adaptive power system stabilizer (PSS) based on the derived generator parameters.

11. The method according to claim 10, wherein the first estimator comprises a single-state estimator configured to derive a first external reactance X E and the IB value, wherein the second estimator is configured to use the first external reactance X E and the IB value as inputs and derive a set of outputs including at least one generator state or a second external reactance X E and wherein the adaptive PSS is configured to use the set of outputs to provide stability of the generator.

12. The method according to claim 11, wherein the plurality of sensor measurements includes a plurality of generator measurements, and wherein the single state estimator is configured to use the plurality of generator measurements to derive the first external reactance X E .

13. The method according to claim 12, wherein the plurality of generator measurement results include generator stator current lst, generator stator voltage Ust, and the phase angle between the stator voltage and the stator current or a combination thereof.

14. The method according to claim 13, wherein the single-state estimator comprises a single-state Kalman filter configured to solve for the first external reactance X using the relationship E , and wherein the IB in the relationship includes a voltage value.

15. The method according to claim 14, wherein the second estimator includes a model that models an internal state of the generator, the internal state including an angle δ between a generator electromagnetic field (EMF) and a reference voltage vector; a generator speed ω; an internal voltage E' of the generator, a magnetic flux ψk in the generator, or a combination thereof.

16. A non-transitory computer-readable medium having computer-executable code stored thereon, the code including instructions for: Obtaining a plurality of sensor measurements via a sensor network; Deriving an infinite bus (IB) value via a first estimator; wherein the first estimator is configured to output the IB value using the plurality of sensor measurements as inputs; Derive the derived generator parameters via a second estimator arranged downstream of the first estimator, wherein the second estimator is configured to output the derived generator parameters using the IB value as an input; and Stabilize the generator via an adaptive power system stabilizer (PSS) based on the derived generator parameters.

17. The non-transitory computer-readable medium according to claim 16, wherein the first estimator comprises a single-state estimator configured to derive a first external reactance X E and the IB value, wherein the second estimator is configured to use the first external reactance X E and the IB value as inputs and derive a set of outputs including at least one generator state or a second external reactance X E and wherein the adaptive PSS is configured to use the set of outputs to provide stability of the generator.

18. The non-transitory computer-readable medium according to claim 17, wherein the plurality of sensor measurements include a generator stator current lst, a generator stator voltage Ust, a phase angle between the stator voltage and the stator current or a combination thereof.

19. The non-transitory computer-readable medium according to claim 18, wherein the single-state estimator includes a single-state Kalman filter configured to solve for the first external reactance X using the relation, and wherein the IB in the relation includes a voltage value. E ​ 20. The non-transitory computer-readable medium according to claim 19, wherein the second estimator includes a model that models an internal state of the generator, the internal state including an angle δ between a generator electromagnetic field (EMF) and a reference voltage vector; a generator speed ω; an internal voltage E' of the generator, a magnetic flux ψk in the generator, or a combination thereof.

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