A method and system for testing the efficiency of a drive train of an offshore wind turbine in the field

Abstract

The application relates to a kind of offshore wind turbine transmission chain efficiency field test method and system, the system includes: main shaft torque test system, main shaft speed test system, high-speed shaft torque test system, high-speed shaft speed test system and data acquisition system;The application adopts high-low speed shaft speed and torque real-time measurement mode, realizes the field test of offshore wind turbine transmission chain efficiency under high-speed operation condition, is important for iterative optimization wind turbine transmission chain structure design, improves the operation reliability of wind turbine, and is important for guaranteeing the stable operation of unit.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of power quality, in particular to a method and system for testing the efficiency of a drive chain of an offshore wind turbine. BACKGROUND

[0002] China is the largest and fastest growing country in the world in terms of wind power. As of the end of 2020, the cumulative installed capacity of wind power nationwide reached 281.53 million kilowatts, an increase of 34.6% compared with the end of 2019. With the continuous increase in the design structure size and rated capacity of wind turbines, the design size and power output level of the drive chain of the wind turbine are also increasing. The efficiency of the drive chain of the wind turbine is a key indicator that affects the output level of the wind turbine, which is determined by the efficiency of each subsystem of the drive chain. This indicator has been a concern for wind turbine manufacturers and wind farm operators. The environmental conditions at wind farms are generally harsh, and the energy loss of the drive chain of the wind turbine under different environmental conditions varies. As the service time of the wind turbine increases, the level of the efficiency of the drive chain of the wind turbine has a particularly significant impact on the output performance of the wind turbine, which in turn has a significant impact on the annual power generation of the entire wind farm. Field testing and verification of the efficiency of the drive chain of the wind turbine can study the efficiency characteristics of the drive chain under different operating conditions, providing input conditions for the design and development of wind turbines.

[0003] For the test of the efficiency of the drive chain of the wind turbine, the current domestic and foreign wind turbine manufacturers generally use the theoretical calculation value of the efficiency of the drive chain to develop the modeling and control strategy of the wind turbine, resulting in a significant difference between the actual performance of the wind turbine and the theoretical design. In particular, after a long period of in-service operation, the structure of the drive chain of the wind turbine ages and the friction intensifies, which directly leads to a significant change in the efficiency level of the drive chain. Currently, the field test of the efficiency of the drive chain of the wind turbine mainly involves pasting a torque strain gauge at the front end of the main shaft (close to the impeller), transmitting the torque signal to the hub, outputting the torque signal via the slip ring communication of the wind turbine, and calculating the active power of the wind turbine to obtain the efficiency of the drive chain. However, the torque measured by this method couples the bending moment signal of the main shaft of the wind turbine, resulting in low accuracy of the torque signal test and failing to truly reflect the efficiency level of the drive chain. It can be seen that the existing test method for the efficiency of the drive chain of the wind turbine has defects such as poor test accuracy and large uncertainty, and cannot realize real-time field testing of the efficiency of the drive chain of the wind turbine. Therefore, there is an urgent need for a field test method and system for the efficiency of the drive chain of the wind turbine suitable for the operating environment. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides a system for testing the efficiency of the drive chain of an offshore wind turbine, which comprises a main shaft torque test system, a main shaft speed test system, a high-speed shaft torque test system, a high-speed shaft speed test system, and a data acquisition system.

[0005] The main shaft torque test system is used for measuring the main shaft torque and outputting a signal.

[0006] The main shaft speed test system is used for measuring the real-time speed of the main shaft.

[0007] The high-speed shaft torque test system is used for measuring the output torque of the high-speed shaft.

[0008] The high-speed shaft speed test system is used for measuring the real-time speed of the high-speed shaft.

[0009] The data acquisition system is used for acquiring test data required for transmission chain efficiency characteristic analysis.

[0010] Further, the offshore wind turbine transmission chain efficiency field test system further comprises a test calculation system, which is used for test calculation based on the signals acquired by the data acquisition system.

[0011] Further, the main shaft torque is measured by pasting strain gauges on the surface of the main shaft to form a Wheatstone bridge.

[0012] Further, a 45-degree type strain gauge is pasted for measurement.

[0013] Further, the main shaft speed is measured by installing a speed encoder or a proximity switch.

[0014] Further, the main shaft torque test system adopts an inductive power supply mode.

[0015] Further, the high-speed shaft speed is measured by installing a speed encoder or a proximity switch.

[0016] Further, the test data required for transmission chain efficiency characteristic analysis is specifically: acquiring main shaft torque signals, main shaft speed signals, high-speed shaft torque signals, high-speed shaft speed signals, and wind turbine control signals.

[0017] Further, the control signals include cabin wind speed, active power, impeller speed, and variable pitch angle.

[0018] Further, the test calculation system is used for test calculation based on the signals acquired by the data acquisition system; specifically, the following formulas (6) to (8) are used for test calculation.

[0019]

[0020]

[0021]

[0022] In the formula, η Shaft , η Generator respectively represent the transmission efficiency of the main shaft and the generator set; η Total represents the efficiency of the transmission chain; M LSS , M HSS respectively represent the torque of the main shaft and the high-speed shaft; ω LSS , ω HSS respectively represent the rotational speed of the main shaft and the high-speed shaft; and P represents the active power of the wind turbine generator set.

[0023] Based on the same inventive concept, the present application provides an offshore wind turbine generator set transmission chain efficiency field test method based on the offshore wind turbine generator set transmission chain efficiency field test system, and the method comprises the following steps:

[0024] Step S1: paste the main shaft torque strain gauge on the surface of the main shaft, measure the main shaft torque and output the signal;

[0025] Step S2: measure the real-time rotational speed of the main shaft;

[0026] Step S3: paste the high-speed shaft torque strain gauge on the surface of the high-speed shaft, and measure the output torque of the high-speed shaft;

[0027] Step S4: measure the real-time rotational speed of the high-speed shaft;

[0028] Step S5: collect the test data required for transmission chain efficiency characteristic analysis;

[0029] Step S6: perform test calculation based on the collected signals.

[0030] Further, the measurement of the main shaft torque and the output of the signal are as follows: when the strain gauge is deformed, the voltage signal output by the Wheatstone bridge is measured, and the strain signal is calculated; after the strain signal is isolated, conditioned, amplified and encoded, it is transmitted through the signal transmission system; the fixed component receives the signal and performs signal demodulation and decoding, and finally decodes the main shaft torque strain signal into an analog voltage signal.

[0031] Based on the same inventive concept, the present application provides an offshore wind turbine generator set transmission chain efficiency field test server, which is used for receiving the collected signals sent by the offshore wind turbine generator set transmission chain efficiency field test system and performing test calculation.

[0032] Based on the same inventive concept, the present application provides an offshore wind turbine generator set transmission chain efficiency field test platform, which comprises the offshore wind turbine generator set transmission chain efficiency field test system and the server; wherein: the offshore wind turbine generator set transmission chain efficiency field test system is used for sending the collected signals to the server; and the server is used for receiving the collected signals and performing test calculation.

[0033] Further, the offshore wind turbine transmission chain efficiency field test system and the server communicate through wired and / or wireless mode.

[0034] Based on the same inventive concept, the present application provides a processor for running a program, wherein the program performs the offshore wind turbine transmission chain efficiency field test method when running.

[0035] Based on the same inventive concept, the present application provides an execution device comprising a processor and a memory coupled to the processor, wherein the memory stores program instructions, and the program instructions stored in the memory, when executed by the processor, implement the offshore wind turbine transmission chain efficiency field test method.

[0036] Based on the same inventive concept, the present application provides a computer readable storage medium comprising a program, which, when running on a computer, causes the computer to execute the offshore wind turbine transmission chain efficiency field test method.

[0037] Compared with the prior art, the present application has the beneficial effects that: the high and low speed shaft rotation speed and torque are measured in real time, the measurement of the wind turbine transmission chain efficiency under high speed operation is realized, the iterative optimization of the wind turbine transmission chain structure design is improved, the operation reliability of the wind turbine is improved, and the stable operation of the unit is important. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 is a typical wind turbine transmission chain structure schematic diagram;

[0039] Figure 2 is a schematic diagram of the offshore wind turbine transmission chain efficiency field test system structure provided by the present application;

[0040] Figure 3 is a schematic diagram of the main shaft torque test system structure of the present application. DETAILED DESCRIPTION

[0041] In order to better understand the present application, the content of the present application will be further described below in combination with the drawings and examples of the specification.

[0042] The offshore wind turbine transmission chain is used to convert the mechanical energy captured by the impeller into electrical energy; as shown in the accompanying Figure 1 The offshore wind turbine transmission chain is composed of a hub, a main shaft, a gear box, a shaft coupling, a generator, etc. The essential characteristic property of the transmission chain is the transmission of torque, i.e. the mechanical torque generated by the rotation of the impeller is transmitted to the input end of the generator.

[0043] Generally, the output characteristics of the wind turbine can be expressed as:

[0044] P(v i )=f(v i )=0.5×ρ×A×v i 3 ×C p (λ,β)×η Equation (1)

[0045] In the formula, ρ is the density of air, in kg·m³. -3 A – Impeller swept area, m 2 ;v i —Wind speed in the i-th interval, m / s; C p (λ,β)——Power coefficient of the i-th interval; λ——Tip speed ratio; β——Blade pitch angle, rad; η represents the transmission chain efficiency. As can be seen from equation (1), the efficiency η of the wind turbine transmission chain is a key indicator affecting the output level of the wind turbine, which is determined by the efficiency of each subsystem of the transmission chain.

[0046] Example 1:

[0047] This invention proposes an on-site testing system for the transmission efficiency of offshore wind turbines. It adopts a method of real-time measurement of shaft speed and torque at high and low speeds to realize on-site testing of the transmission efficiency of offshore wind turbines under high-speed operation conditions. At the same time, by real-time acquisition of signals such as nacelle wind speed, active power, rotor speed, and pitch angle output by the wind turbine main control system, the output characteristics of the wind turbine transmission efficiency are analyzed.

[0048] The structural principle of the offshore wind turbine drivetrain efficiency field testing system is shown in the attached figure. Figure 2 As shown, this transmission chain efficiency characteristic measurement system consists of a spindle torque testing system, a spindle speed testing system, a high-speed shaft torque testing system, a high-speed shaft speed testing system, and a data acquisition system. The functions of each system are described below:

[0049] The spindle torque testing system is used to measure spindle torque and output a signal; preferably, the spindle torque is measured by attaching strain gauges to the spindle surface to form a Wheatstone bridge, for example, by attaching 45-degree strain gauges for measurement.

[0050] As attached Figure 3As shown, considering that the main shaft is in a rotating state during normal operation of the wind turbine, the main shaft torque testing system adopts an inductive power supply mode; the main shaft torque testing system comprises an inductive power supply system, a strain conditioning system, a signal coding system, a signal transmitting system, a signal receiving system and a signal demodulation system; wherein: the inductive power supply system is used to provide energy for the strain conditioning system, the signal coding system and the signal transmitting system in an inductive mode; the signal receiving system and the signal demodulation system are provided with energy by a fixed power supply; when the strain gauge is deformed, the voltage signal output by the Wheatstone bridge is measured, and the strain signal is calculated; after the strain signal is isolated, conditioned, amplified and coded, it is transmitted by the signal transmitting system; the signal receiving system receives the signal transmitted by the signal transmitting system and performs signal demodulation and decoding, finally decodes the main shaft torque strain signal into an analog voltage signal, thereby realizing the measurement of the main shaft torque, and accessing the data acquisition system.

[0051] Preferably: the analog voltage signal is a 0-10V analog voltage signal.

[0052] When the measured structure is deformed, the bridge arm resistance values on the bridge are changed to R1+△R1, R2+△R2, R3+△R3 and R4+△R4 respectively, at which time the output voltage of the bridge is:

[0053]

[0054]

[0055]

[0056] The strain signal is:

[0057] ε d = ε1- ε2- ε3+ ε4 Formula (5)

[0058] The main shaft speed testing system is used to measure the real-time speed of the main shaft. The measurement of the main shaft speed is realized by installing a speed encoder or a proximity switch, and the measured speed signal is accessed to the data acquisition system.

[0059] The high-speed shaft torque testing system is used to measure the output torque of the high-speed shaft, and the measurement method is the same as that of the main shaft torque testing system, which also adopts an inductive power supply mode.

[0060] The high-speed shaft speed testing system is used to measure the real-time speed of the high-speed shaft. The measurement of the high-speed shaft speed is realized by installing a speed encoder or a proximity switch, and the measured speed signal is accessed to the data acquisition system.

[0061] The data acquisition system is used for acquiring test data required for transmission chain efficiency characteristic analysis, specifically, acquiring main shaft torque signals, main shaft speed signals, high-speed shaft torque signals, high-speed shaft speed signals and control signals of the wind turbine itself, wherein the control signals of the wind turbine itself include cabin wind speed, active power, impeller speed, variable pitch angle and the like.

[0062] The offshore wind turbine transmission chain efficiency field test system further comprises a test calculation system, which is used for test calculation based on the signals acquired by the data acquisition system, specifically, test calculation is performed by using the following formulas (6) to (8).

[0063]

[0064]

[0065]

[0066] In the formula, η Shaft , η Generator respectively represent the transmission efficiency of the main shaft and the transmission efficiency of the generator set; η Total represents the efficiency of the transmission chain; M LSS , M HSS respectively represent the torque of the main shaft and the high-speed shaft; ω LSS , ω HSS respectively represent the speed of the main shaft and the high-speed shaft; and P represents the active power of the wind turbine.

[0067] Embodiment 2

[0068] Based on the same inventive concept, the present application proposes an offshore wind turbine transmission chain efficiency field test method, which comprises the following steps:

[0069] Step S1: Paste the main shaft torque strain gauge on the surface of the main shaft; measure the main shaft torque and output signals; specifically, when the strain gauge deforms, measure the voltage signal output by the Wheatstone bridge and calculate the strain signal; after isolation conditioning amplification and coding of the strain signal, the signal is transmitted through the signal transmission system; the fixed component receives the signal and performs signal demodulation and decoding, and finally decodes the main shaft torque strain signal into an analog voltage signal of 0-10V.

[0070] Preferably, a 45-degree type strain gauge is used for measurement.

[0071] The measurement of the main shaft torque adopts an inductive power supply mode, and a copper coil is wound on the surface of the main shaft to form an inductive power supply.

[0072] Step S2: measuring the real-time rotating speed of the main shaft. The measurement of the rotating speed of the main shaft is realized by installing a rotating speed encoder or a proximity switch, and the measured rotating speed signal is connected to a data acquisition system.

[0073] Step S3: sticking the high-speed shaft torque strain gauge on the surface of the high-speed shaft; measuring the output torque of the high-speed shaft; specifically, when the strain gauge deforms, the voltage signal output by the Wheatstone bridge is measured, and the strain signal is calculated; after the strain signal is isolated, conditioned, amplified and encoded, it is transmitted through a signal transmission system; after the signal is received by the fixed component, signal demodulation and decoding are performed, and finally the high-speed shaft torque strain signal is decoded into an analog voltage signal.

[0074] Preferably, the measurement of the high-speed shaft is realized by inductive power supply, that is, a copper coil is wound on the surface of the high-speed shaft to form an inductive power supply.

[0075] Step S4: measuring the real-time rotating speed of the high-speed shaft. The measurement of the rotating speed of the high-speed shaft is realized by installing a rotating speed encoder or a proximity switch.

[0076] Step S5: collecting the test data required for the efficiency characteristic analysis of the transmission chain; specifically, the main shaft torque signal, the main shaft rotating speed signal, the high-speed shaft torque signal, the high-speed shaft rotating speed signal and the control signal of the wind turbine generator system itself are collected; wherein, the control signal of the wind turbine generator system itself includes the nacelle wind speed, the active power, the impeller rotating speed, the variable pitch angle, etc.

[0077] Step S6: performing test calculation based on the collected signals; specifically, the following formula (6) to (8) are used for test calculation.

[0078]

[0079]

[0080]

[0081] In the formula, η Shaft , η Generator respectively represent the transmission efficiency of the main shaft and the transmission efficiency of the generator set; η Total represents the efficiency of the transmission chain; M LSS , M HSS respectively represent the torque of the main shaft and the high-speed shaft; ω LSS , ω HSS respectively represent the rotating speed of the main shaft and the high-speed shaft; P represents the active power of the wind turbine generator system.

[0082] Example 3

[0083] Based on the same inventive concept, the application provides a server for testing efficiency of a transmission chain of an offshore wind turbine, which is used for receiving collected signals transmitted by the system for testing efficiency of the transmission chain of the offshore wind turbine and performing test calculation.

[0084] Preferably, the server is a distributed server.

[0085] Preferably, the server is a cloud server.

[0086] Embodiment 4

[0087] Based on the same inventive concept, the application provides a platform for testing efficiency of a transmission chain of an offshore wind turbine, which comprises the system for testing efficiency of the transmission chain of the offshore wind turbine and a server, wherein the system for testing efficiency of the transmission chain of the offshore wind turbine is used for transmitting collected signals to the server, and the server is used for receiving the collected signals and performing test calculation.

[0088] Preferably, the system for testing efficiency of the transmission chain of the offshore wind turbine and the server communicate through wired and / or wireless mode.

[0089] Preferably, the collected signals are transmitted through a network.

[0090] Alternatively, the collected signals are transmitted through a message.

[0091] Those skilled in the art should understand that the embodiments of the application can be provided as a method, a system, or a computer program product. Therefore, the application can be in the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the application can be in the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memory, CD-ROM, optical memory, etc.) containing computer-usable program code.

[0092] The application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of the flows and / or blocks, can be implemented by computer program instructions. These computer program instructions can be provided to a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to produce a machine, so that the instructions executed by the computer or other programmable data processing devices produce a device that implements the functions specified in the flowcharts and / or block diagrams. Figure 1 The functions specified in one or more flows and / or blocks Figure 1 The device that implements the functions specified in one or more flows and / or blocks.

[0093] These computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture including instructions which implement the flow Figure 1 of the flow or flows and / or blocks Figure 1 of the block or blocks specified in the flow.

[0094] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the flow Figure 1 of the flow or flows and / or blocks Figure 1 of the block or blocks specified in the flow.

[0095] Finally, it should be noted that the above-mentioned embodiments are merely used to illustrate the technical solutions of the present application, rather than limit the present application. Although the present application has been described in detail with reference to the above-mentioned embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or equivalent replaced without departing from the spirit and scope of the present application, and any modification or equivalent replacement should be covered in the protection scope of the claims of the present application.

Claims

1. A field testing system for the efficiency of an offshore wind turbine drive train, characterized in that, The system includes: a spindle torque testing system, a spindle speed testing system, a high-speed shaft torque testing system, a high-speed shaft speed testing system, and a data acquisition system; The spindle torque testing system is used to measure the spindle torque and output a signal; The spindle speed testing system is used to measure the real-time speed of the spindle; The high-speed shaft torque testing system is used to measure the output torque of the high-speed shaft; The high-speed shaft speed testing system is used to measure the real-time speed of the high-speed shaft. The data acquisition system is used to collect test data required for the analysis of transmission chain efficiency characteristics; The offshore wind turbine drive train efficiency field testing system also includes a test calculation system, which is used to perform test calculations based on the signals collected by the data acquisition system. The test calculation system is used to perform test calculations based on the signals acquired by the data acquisition system; specifically, it uses the following formulas (6) to (8) to perform test calculations. In the formula, η Shaft η Generator η represents the transmission efficiency of the main shaft and the transmission efficiency of the generator set, respectively. Total Indicates the efficiency of the transmission chain; M LSS M HSS These represent the torques of the main spindle and the high-speed shaft, respectively; ω LSS ω HSS These represent the rotational speeds of the main shaft and the high-speed shaft, respectively; P represents the active power of the wind turbine.

2. The system as described in claim 1, characterized in that, The spindle torque is measured by attaching strain gauges to the spindle surface to form a Wheatstone bridge.

3. The system as described in claim 2, characterized in that, Measurements were taken using 45-degree adhesive strain gauges.

4. The system as described in claim 2, characterized in that, The spindle speed is measured by installing a speed encoder or proximity switch.

5. The system as described in claim 2, characterized in that, The spindle torque testing system uses inductive power supply.

6. The system as described in claim 2, characterized in that, The high-speed shaft speed is measured by installing a speed encoder or proximity switch.

7. The system as described in claim 2, characterized in that, The test data required for collecting transmission chain efficiency characteristics analysis specifically includes: collecting main shaft torque signal, main shaft speed signal, high-speed shaft torque signal, high-speed shaft speed signal, and the wind turbine's own control signals.

8. The system as described in claim 7, characterized in that, The control signals of the engine itself include nacelle wind speed, active power, impeller speed, and pitch angle.

9. A method for on-site testing of the efficiency of an offshore wind turbine drivetrain based on the on-site testing system for the efficiency of an offshore wind turbine drivetrain according to any one of claims 1-8, characterized in that, The method includes: Step S1: Attach the spindle torque strain gauge to the spindle surface, measure the spindle torque and output a signal; Step S2: Measure the real-time speed of the spindle; Step S3: Attach the high-speed shaft torque strain gauge to the surface of the high-speed shaft and measure the output torque of the high-speed shaft; Step S4: Measure the real-time rotational speed of the high-speed shaft; Step S5: Collect the test data required for transmission chain efficiency characteristic analysis; Step S6: Perform test calculations based on the acquired signals.

10. The method as described in claim 9, characterized in that, The process of measuring spindle torque and outputting a signal specifically involves: measuring the voltage signal output by the Wheatstone bridge when the strain gauge deforms, and calculating the strain signal; isolating, conditioning, amplifying, and encoding the strain signal, and then transmitting it through a signal transmission system; receiving the signal and demodulating and decoding it, ultimately decoding the spindle torque strain signal into an analog voltage signal.

11. A field test server for the efficiency of an offshore wind turbine drive train, characterized in that, The server is used to receive the acquisition signals sent by the offshore wind turbine drive train efficiency field test system as described in any one of claims 1-8 and to perform test calculations.

12. A field testing platform for the efficiency of an offshore wind turbine drive train, characterized in that, The platform includes an offshore wind turbine drivetrain efficiency field testing system and a server as described in any one of claims 1-8; wherein: the offshore wind turbine drivetrain efficiency field testing system is used to send the collected signals to the server; the server is used to receive the collected signals and perform test calculations.

13. The platform as described in claim 12, characterized in that, The offshore wind turbine drivetrain efficiency field testing system and the server communicate via wired and / or wireless means.

14. A processor, characterized in that, The processor is used to run a program, wherein the program executes the on-site testing method for the efficiency of the offshore wind turbine drive train as described in claim 9.

15. An execution device, characterized in that, The device includes a processor coupled to a memory, the memory storing program instructions, which, when executed by the processor, implement the on-site testing method for the transmission chain efficiency of an offshore wind turbine as described in claim 9.

16. A computer-readable storage medium, characterized in that, Includes a program that, when run on a computer, causes the computer to perform the field test method for the efficiency of the offshore wind turbine drive train as described in claim 9.

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