The present disclosure relates generally to wind turbines, and more particularly, to systems and methods for optimizing scheduling of technical standby tests/health checks such that the tests occur during periods of low wind speeds so as to minimize energy loss.
Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modern wind turbine typically includes a tower, generator, gearbox, nacelle, and one or more rotor blades. The rotor blades capture kinetic energy of wind using known airfoil principles. For example, rotor blades typically have the cross-sectional profile of an airfoil such that, during operation, air flows over the blade producing a pressure difference between the sides. Consequently, a lift force, which is directed from a pressure side towards a suction side, acts on the blade. The lift force generates torque on the main rotor shaft, which is geared to a generator for producing electricity. In addition, a plurality of the wind turbines may be arranged in a predetermined geological location and electrically connected together to form a wind farm.
During operation, wind impacts the rotor blades of the wind turbine and the blades transform wind energy into a mechanical rotational torque that rotatably drives a low-speed shaft. The low-speed shaft is configured to drive the gearbox that subsequently steps up the low rotational speed of the low-speed shaft to drive a high-speed shaft at an increased rotational speed. The high-speed shaft is generally rotatably coupled to a generator so as to rotatably drive a generator rotor. As such, a rotating magnetic field may be induced by the generator rotor and a voltage may be induced within a generator stator that is magnetically coupled to the generator rotor. In certain configurations, the associated electrical power can be transmitted to a turbine transformer that is typically connected to a power grid via a grid breaker. Thus, the turbine transformer steps up the voltage amplitude of the electrical power such that the transformed electrical power may be further transmitted to the power grid.
In many wind turbines, the generator rotor may be electrically coupled to a bi-directional power converter that includes a rotor side converter joined to a line side converter via a regulated DC link. More specifically, some wind turbines, such as wind-driven doubly-fed induction generator (DFIG) systems or full power conversion systems, may include a power converter with an AC-DC-AC topology.
Current wind turbine maintenance strategies include various technical standby tests or health checks (e.g. as recommended by the International Electrotechnical Commission, IEC) which are executed during specific periods of time in order to ensure safe operation of wind turbine. For example, for certain wind turbines, technical standby (TS) tests/checks are conducted periodically and/or conditionally to check the health of the wind turbine subsystems by stopping the wind turbine. As such, each test is scheduled to run after a specific period of time has passed from the last successful time the test was executed.
Although each test may vary between about 8 and 45 minutes in duration, the cumulative downtime due to each test in a year can be significant. Thus, such tests impact the availability of the wind turbine for the customers. In addition, since these tests are conducted as a function of time, there is high probability of higher annual energy production (AEP) loss due to the tests being conducted during higher wind speed conditions. In addition to negatively impacting AEP, current processes for scheduling of the tests increase the effort of tracking the time passed for each test per wind turbine and then re-scheduling the test.
In view of the foregoing, it would be advantageous to optimize scheduling of the health checks such that the checks occur during the lowest wind period possible so as to minimize AEP loss.
Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.
In one aspect, the present disclosure is directed to a method for improving power production of a wind turbine. The method includes obtaining, by a controller having one or more processors, wind forecast data of the wind turbine. The method also includes scheduling, by the controller, one or more health checks for one or more components of the wind turbine based, at least in part, on the wind forecast data. Moreover, the method includes implementing, via the controller, the one or more health checks based on the scheduling such that the one or more health checks are implemented during time periods having wind speeds below a predetermined threshold.
In an embodiment, the wind forecast data may include, for example, online or time-series-based statistical wind forecast data. In addition, the wind forecast data may include wind speed and/or wind direction.
In another embodiment, the method may include scheduling the one or more health checks based on the wind forecast data and previous test data and/or a periodic predetermined wind threshold based historical site data analysis. In further embodiments, the method may include scheduling the one or more health checks automatically.
In additional embodiments, the method may include adjusting the scheduling based on changes in wind data that differs from the wind forecast data of the wind turbine.
In several embodiments, the wind turbine may be part of a wind farm having a plurality of wind turbines. In such embodiments, the method may include scheduling the health check(s) based on the wind forecast data and at least one of a maximum power output of the wind farm or a maximum power loss allowed per wind turbine in the wind farm.
In further embodiments, the method may also include prioritizing the health check (s) for the plurality of wind turbines in the wind farm based on at least one of the wind forecast or previous test data.
In particular embodiments, the method may include determining the wind forecast data of the wind turbine for at most five days in advance or any other suitable time frame. In additional embodiments, the method may include tracking the health check (s) and monitoring a time elapsed between health checks.
In several embodiments, obtaining the wind forecast data of the wind turbine may include calibrating estimated patterns of wind data with actual measured wind data.
In another aspect, the present disclosure is directed to a system for improving power production of a wind farm having a plurality of wind turbines. The system includes a farm-level controller configured to perform a plurality of operations, including but not limited to obtaining a plurality of wind conditions from the plurality of wind turbines, determining a schedule for one or more health checks for one or more components of the plurality of wind turbines based, at least in part, on the one or more wind conditions, and sending the schedule to turbine controllers of the plurality of wind turbines. The system also includes a plurality of turbine-level controllers communicatively coupled to the farm-level controller. Each of the plurality of turbine-level controllers is also configured to perform a plurality of operations, including but not limited to implementing the health checks(s) based on the schedule such that the health checks(s) are implemented during time periods with a power output below a predetermined threshold.
In yet another aspect, the present disclosure is directed to a method for improving power production of a wind turbine. The method includes obtaining, by a controller having one or more processors and one or more memory devices, one or more wind conditions at the wind turbine. The method also includes scheduling, by the controller, one or more health checks for one or more components of the wind turbine based, at least in part, on the one or more wind conditions. Moreover, the method includes implementing, via the controller, the health checks(s) based on the scheduling such that the health checks(s) are implemented during time periods with a power output below a predetermined threshold.
It should be understood that variations and modifications can be made to these example embodiments of the present disclosure.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and 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.
A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:
Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.
Referring now to the drawings,
In the example system 100, a rotor 106 includes a plurality of rotor blades 108 coupled to a rotating hub 110. The rotor 106 is coupled to an optional gearbox 118, which is, in turn, coupled to a generator 120. In accordance with aspects of the present disclosure, the generator 120 may be a doubly fed induction generator (DFIG) 120. Accordingly, the DFIG 120 can include a rotor and a stator. Further, as shown, the DFIG 120 is typically coupled to a stator bus 154 and a power converter 162 via a rotor bus 156. The stator bus 154 provides an output multiphase power (e.g. three-phase power) from a stator of the DFIG 120 and the rotor bus 156 provides an output multiphase power (e.g. three-phase power) of a rotor of the DFIG 120. Referring to the power converter 162, the DFIG 120 is coupled via the rotor bus 156 to a rotor side converter 166. The rotor side converter 166 is coupled to a line side converter 168 which in turn is coupled to a line side bus 188.
In example configurations, the rotor side converter 166 and the line side converter 168 are configured for normal operating mode in a three-phase, pulse width modulation (PWM) arrangement using insulated gate bipolar transistor (IGBT) or similar switching elements. The rotor side converter 166 and the line side converter 168 can be coupled via a DC link 136 across which is the DC link capacitor 138. In an embodiment, a transformer 178, such as a three-winding transformer, can be coupled to the line bus 188, the stator bus 154, and a system bus 160. The transformer 178 can convert the voltage of power from the line bus 188 and the stator bus 154 to a voltage suitable for providing to an electrical grid 184 via system bus 160.
The power conversion system 162 can be coupled to a control device 174 to control the operation of the rotor side converter 166 and the line side converter 168. It should be noted that the control device 174, in typical embodiments, is configured as an interface between the power conversion system 162 and a turbine control system 176. In one implementation, the control device 174 can include a processing device (e.g. microprocessor, microcontroller, etc.) executing computer-readable instructions stored in a computer-readable medium. The instructions when executed by the processing device can cause the processing device to perform operations, including providing control commands (e.g. pulse width modulation commands) to the switching elements of the power converter 162 and other aspects of the wind turbine system 100.
In operation, alternating current power generated at the DFIG 120 by rotation of the rotor 106 is provided via a dual path to electrical grid 184. The dual paths are defined by the stator bus 154 and the rotor bus 156. On the rotor bus side 156, sinusoidal multi-phase (e.g. three-phase) alternating current (AC) power is provided to the power converter 162. The rotor side power converter 166 converts the AC power provided from the rotor bus 156 into direct current (DC) power and provides the DC power to the DC link 136. Switching elements (e.g. IGBTs) used in bridge circuits of the rotor side power converter 166 can be modulated to convert the AC power provided from the rotor bus 156 into DC power suitable for the DC link 136.
The line side converter 168 converts the DC power on the DC link 136 into AC output power suitable for the electrical grid 184, such as AC power synchronous to the electrical grid 184, which can be transformed by the transformer 178 before being provided to the electrical grid 184. In particular, switching elements (e.g. IGBTs) used in bridge circuits of the line side power converter 168 can be modulated to convert the DC power on the DC link 136 into AC power on the line side bus 188. The AC power from the power converter 162 can be combined with the power from the stator of DFIG 120 to provide multi-phase power (e.g. three-phase power) having a frequency maintained substantially at the frequency of the electrical grid 184 (e.g. 50 Hz/60 Hz).
The power converter 162 can receive control signals from, for instance, the control system 174. The control signals can be based, among other things, on sensed conditions or operating characteristics of the wind turbine system 100. Typically, the control signals provide for control of the operation of the power converter 162. For example, feedback in the form of sensed speed of the DFIG 120 can be used to control the conversion of the output power from the rotor bus 156 to maintain a proper and balanced multi-phase (e.g. three-phase) power supply. Other feedback from other sensors can also be used by the controller 174 to control the power converter 162, including, for example, stator and rotor bus voltages and current feedbacks. Using the various forms of feedback information, switching control signals (e.g. gate timing commands for IGBTs), stator synchronizing control signals, and circuit breaker signals can be generated.
Various circuit breakers and switches, such as a line bus breaker 186, stator bus breaker 158, and grid breaker 182 can be included in the system 100 to connect or disconnect corresponding buses, for example, when current flow is excessive and can damage components of the wind turbine system 100 or for other operational considerations. Additional protection components can also be included in the wind turbine system 100.
Referring now to
Referring now to
In contrast to conventional systems such as those illustrated in
In addition, as shown, the transformers 140, 142, 144 may be connected to a main line 155 that combines the voltage from each cluster 137 before sending the power to the grid. Further, as mentioned, each of the clusters 137 may be communicatively coupled with a cluster-level controller 109 that controls each of the transformers 140, 142, 144. In addition, as shown, the wind farm 105 may include one or more automatic voltage regulators (e.g. tap changers 164) arranged with each of the transformers 140, 142, 144 and/or one or more reactive power devices 170. For example, as shown, the reactive power devices 170 may include any one of the following: a capacitor bank 172, a reactor bank 175, and/or a static synchronous compensator (STATCOM) 177.
In addition, as shown, the wind turbine systems 100 described herein may include one or more controllers. For example, the system 100 may include a farm-level controller 190, one or more cluster-level controllers 179, one or more turbine-level controllers 176 and/or one or more converter controllers 174. As such, the various controllers described herein are configured to control any of the components of the wind farm 105, the wind turbine clusters 137, and/or the individual wind turbines 100 and/or implement the method steps as described herein.
Referring now to
The processor(s) 512 and memory device(s) 514 can be configured to perform a variety of computer-implemented functions and/or instructions (e.g., performing the methods, steps, calculations and the like and storing relevant data as disclosed herein). The instructions when executed by the processor(s) 512 can cause the processor(s) 512 to perform operations according to example aspects of the present disclosure. For instance, the instructions when executed by the processor(s) 512 can cause the processor(s) 512 to implement the methods discussed herein.
Additionally, the control device 510 can include a communication interface 516 to facilitate communications between the control device 510 and various components of a wind turbine system, wind farm, or power system, including reactive power production requirements or sensed operating parameters as described herein. Further, the communication interface 518 can include a sensor interface 518 (e.g., one or more analog-to-digital converters) to permit signals transmitted from one or more sensors 520, 522 to be converted into signals that can be understood and processed by the processor(s) 512. It should be appreciated that the sensors (e.g. sensors 520, 522) can be communicatively coupled to the communications interface 518 using any suitable means, such as a wired or wireless connection. The signals can be communicated using any suitable communications protocol. The sensors (520, 522) can be, for example, voltage sensors, current sensors, power sensors, DFIG rotational speed sensors, temperature sensors, or any other sensor device described herein.
As such, the processor(s) 512 can be configured to receive one or more signals from the sensors 520, 522. For instance, in some embodiments, the processor(s) 512 can receive signals indicative of a voltage or current from the sensor 520. In some embodiments, the processor(s) 512 can receive signals indicative of temperature (e.g. DFIG temperature, line side converter temperature) from sensor 522.
As used herein, the term “processor” refers not only to integrated circuits referred to in the art as being included in a computer, but also refers to a control device, a microcontrol device, a microcomputer, a programmable logic control device (PLC), an application specific integrated circuit, and other programmable circuits. Additionally, the memory device(s) 514 can generally include memory element(s) including, but not limited to, computer readable medium (e.g., random access memory (RAM)), computer readable non-volatile medium (e.g., a flash memory), a compact disc-read only memory (CD-ROM), a magneto-optical disk (MOD), a digital versatile disc (DVD) and/or other suitable memory elements. Such memory device(s) 514 can generally be configured to store suitable computer-readable instructions that, when implemented by the processor(s) 512, configure the control device 510 to perform the various functions as described herein.
Referring now to
As shown at 302, the method 300 can include obtaining wind forecast data of the wind turbine(s) 100 by the controller. For example, in an embodiment, the method 300 may include determining the wind forecast data of the wind turbine 100 for any suitable future time frame, such as at most five days in advance. In addition, it should be understood that the wind forecast data may include data corresponding to wind speed, wind turbulence, wind gusts, wind direction, wind acceleration, wind shear, wind veer, wake, or any other wind parameter. Further, the controller described herein can be operatively connected to one or more sensors, such as one or more wind sensors, and can be configured to receive measurements indicative of various wind conditions in the wind farm 200 that can be used to estimate the wind forecast data. Moreover, the step of obtaining the wind forecast data of the wind turbine 100 may further include calibrating estimated patterns of wind data with actual measured wind data and predicting the wind forecast data based on the calibrations.
Referring still to
Thus, in certain embodiments, the controller may include an algorithm which optimizes the schedule of such health checks by utilizing wind forecast data to ensure the health checks occur during a low wind speed period. In certain instances, for example, the controller may utilize specialized software, such as edge computing, which generally refers to a distributed computing paradigm that brings computation and data storage closer to the location where it is needed to improve response times and save bandwidth. Accordingly, in an embodiment, the algorithm may optimize scheduling of the health check(s) based on the wind forecast data (e.g. by scheduling the health check(s) during periods of low or no wind), previous test data (e.g. by scheduling the health check(s) a predetermined time after a previous test has been completed successfully), a maximum power output of the wind farm 200, and/or a maximum power loss allowed per wind turbine in the wind farm 200. In further embodiments, the method 300 may also include prioritizing the health check(s) for the plurality of wind turbines 100 in the wind farm 200 based on the wind forecast and/or previous test data. In another embodiment, the method 300 may include scheduling the health check(s) for determining the overall health of the wind turbine 100 automatically or manually.
Moreover, in additional embodiments, the method 300 may also include adjusting the scheduling based on changes in wind data that differs from the wind forecast data of the wind turbine system 100. For example, in certain instances, the algorithm may schedule for a better window of opportunity (e.g. less or no wind), if available, when the forecast wind speed changes. In additional embodiments, the method 300 may also include tracking the health check(s) and monitoring a time elapsed between health checks. Accordingly, the controller may consider the elapsed time between health check(s) when developing the schedule.
Referring back to
Referring now to
As shown at 402, the method 400 can include obtaining one or more wind conditions at the wind turbine(s) 100 by the controller. For example, in an embodiment, the one or more wind conditions at the wind turbine(s) 100 may include data corresponding to wind speed, wind turbulence, wind gusts, wind direction, wind acceleration, wind shear, wind veer, wake, or any other wind parameter. Further, as mentioned, the controller described herein can be operatively connected to one or more sensors, such as one or more wind sensors, and can be configured to receive measurements indicative of various wind conditions in the wind farm 200.
As shown at 404, the method 400 may include scheduling, by the controller, one or more health checks for one or more components of the wind turbine 100 based, at least in part, on the one or more wind conditions. As shown at 406, the method 400 may include implementing, via the controller, the health check(s) based on the scheduling such that the health check(s) are implemented during time periods with a power output below a predetermined threshold.
The technology discussed herein makes reference to computer-based systems and actions taken by and information sent to and from computer-based systems. One of ordinary skill in the art will recognize that the inherent flexibility of computer-based systems allows for a great variety of possible configurations, combinations, and divisions of tasks and functionality between and among components. For instance, processes discussed herein can be implemented using a single computing device or multiple computing devices working in combination. Databases, memory, instructions, and applications can be implemented on a single system or distributed across multiple systems. Distributed components can operate sequentially or in parallel.
Although specific features of various embodiments may be shown in some drawings and not in others, this is for convenience only. In accordance with the principles of the present disclosure, any feature of a drawing may be referenced and/or claimed in combination with any feature of any other drawing.
Various aspects and embodiments of the present invention are defined by the following numbered clauses:
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 devices or systems and performing any incorporated methods. 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 include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
Number | Date | Country | Kind |
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201921042374 | Oct 2019 | IN | national |