Remote synchronous measurement system and method for wind farm collector line fault monitoring

Abstract

The present invention provides a remote synchronous measurement system for monitoring faults in wind farm collector lines, comprising: a plurality of synchronous measurement units, each installed in a corresponding wind turbine chassis transformer cabinet. The synchronous measurement unit comprises: a main processor, responsible for controlling the synchronous measurement unit, including setting a sampling cycle time; a GPS module, for receiving a satellite pulse-second signal; a counter module, for generating a first count value, clearing the first count value to zero and restarting counting based on the pulse-second signal output by the GPS module; a comparison module, for generating a corresponding count time based on the first count value, and generating a synchronous sampling pulse signal and a clearing signal when the count time is equal to the sampling cycle time; an A / D conversion module, triggered and started by the synchronous sampling pulse signal, to achieve analog-to-digital conversion of wind turbine electrical quantities, and to provide the conversion result to the main processor. The present invention also provides a remote synchronous measurement method for monitoring faults in wind farm collector lines.

Description

Technical Field

[0001] The present invention relates to the electronic technical field of wind farm collector line fault detection, and in particular to a remote synchronous measurement system and method for wind farm collector line fault monitoring. Background Art

[0002] A wind farm contains multiple collector lines, such as Figure 1 As shown, each collector line connects multiple wind turbine chassis-type transformers. The electricity generated by each wind turbine is collected by the wind turbine chassis-type transformer (a simple box-type substation) and then transmitted to the line through a transformer at a booster station. During wind farm operation, short circuits in the collector line can occur, causing power outages. Therefore, timely and accurate short-circuit fault location is crucial for minimizing power losses in wind farms.

[0003] When a collector line short-circuit fault occurs, it causes changes in line voltage and current, and also in the output current of each wind turbine box transformer branch (the branch connecting the wind turbine box transformer to the collector line). Locating a collector line short-circuit fault based on fault analysis requires the synchronized phasors of the output currents of each wind turbine box transformer branch as an analysis basis, so the output current signals of each wind turbine box transformer branch must be measured simultaneously.

[0004] Since the wind turbines are geographically dispersed, how to achieve accurate and synchronous measurement of the electrical quantities of each wind turbine box transformer branch has become a difficult problem that needs to be solved urgently. Summary of the Invention

[0005] The purpose of the present invention is to provide a remote synchronous measurement system and method for wind farm collector line fault monitoring, which can accurately collect multiple current signals output by multiple geographically dispersed wind turbines and ensure high synchronization of the collected data to meet the needs of wind farm collector line fault monitoring.

[0006] To achieve the above-mentioned object, the present invention provides a remote synchronous measurement system for monitoring faults in a wind farm collector line, wherein the wind farm comprises an electrically connected collector line and a plurality of wind turbines, and the remote synchronous measurement system comprises: a plurality of synchronous measurement units, each for performing real-time synchronous measurement of electrical quantity signals of the plurality of wind turbines;

[0007] The synchronous measurement unit comprises:

[0008] The main processor is responsible for the overall control of the synchronous measurement unit, including setting the sampling cycle time for real-time synchronous measurement;

[0009] GPS module, used to receive satellite pulse-second signals;

[0010] a counter module for performing nanosecond counting and generating a first count value; the counter module signal is connected to the GPS module, and resets the first count value to zero and restarts counting based on the received second pulse signal, so as to achieve second-level synchronization between the synchronous measurement units;

[0011] a comparison module connected to the counter module, generating a corresponding counting time based on the first counting value; when the counting time is equal to the sampling cycle time, the comparison module generates a synchronous sampling pulse signal and a reset signal; the counter module resets the first counting value to zero and restarts counting based on the reset signal;

[0012] The A / D conversion module receives the electrical quantity signal of the corresponding fan and connects the comparison module and the main processor through digital signals. The A / D conversion module is triggered and started by the synchronous sampling pulse signal to realize the analog-to-digital conversion of the fan electrical quantity signal and provide the conversion result to the main processor.

[0013] Optionally, the counter module includes: a crystal oscillator and a counter; the crystal oscillator is used to generate a clock signal, and the counter generates a first count value based on the clock signal.

[0014] Optionally, the remote synchronous measurement system for wind farm collector line fault monitoring further includes a sampling cycle time storage module, whose digital signal is connected to the main processor and the comparison module, and is used to receive and store the sampling cycle time sent by the main processor and provide it to the comparison module.

[0015] Optionally, the GPS module also provides a second pulse signal to the main processor; the main processor generates a corresponding second count value based on the number of received A / D conversion results, and when the main processor receives the second pulse signal, the second count value is cleared and restarts counting; the main processor also generates a corresponding four-tuple based on the received A / D conversion result, and the four-tuple includes: the corresponding wind turbine number, the A / D conversion result, the corresponding second pulse sequence number, and the corresponding second count value.

[0016] Optionally, the remote synchronous measurement system for wind farm collector line fault monitoring further includes a wireless communication module, which is connected between the main processor and the host computer and is used to send the quadruple to the host computer.

[0017] Optionally, the host computer generates a corresponding measurement data vector X based on the received quaternary group t,j ,in M represents the total number of fans; i represents the fan number; j represents the second count value; t represents the second pulse number; It indicates the jth A / D conversion result collected for the fan numbered i between the second pulses numbered t and t+1.

[0018] Optionally, the main processing module adopts a CPU or FPGA.

[0019] The present invention also provides a remote synchronous measurement method for monitoring faults in wind farm collector lines, which is applied to the remote synchronous measurement system for monitoring faults in wind farm collector lines as described in the present invention. The remote synchronous measurement method comprises the following steps:

[0020] S1. The main processor sets the sampling cycle time and stores it in the sampling cycle storage module; the first count value is reset to zero;

[0021] S2, the counter module starts nanosecond counting and generates a first count value; if the counter module receives a second pulse signal, the first count value is reset to zero and step S2 is repeated; otherwise, the process proceeds to S3;

[0022] S3. When the counting time is equal to the sampling cycle time, the comparison module generates a synchronous sampling pulse signal and a reset signal; the synchronous sampling pulse signal triggers the A / D conversion module to convert the electrical quantity signal of the corresponding fan into the corresponding A / D conversion result, and the A / D conversion result is sent to the host computer through the main processor; the counter module resets the first count value based on the reset signal; and enters S2.

[0023] Optionally, the step S3 of sending the A / D conversion result to the host computer through the main processor includes the following steps:

[0024] S31, the main processor further generates a corresponding second count value based on the number of received A / D conversion results, and when the main processor receives a second pulse signal, the second count value is reset to zero and restarts counting;

[0025] S32. The main processor generates a corresponding four-tuple based on the received A / D conversion result, wherein the four-tuple includes: a corresponding wind turbine number, an A / D conversion result, a corresponding second pulse sequence number, and a corresponding second count value;

[0026] S33. The main processor sends the quaternary group to the host computer.

[0027] Optionally, step S33 further includes: the host computer generates multiple measurement data vectors based on the received quaternary group, wherein the measurement data vectors include A / D conversion results of multiple wind turbines collected at the same time, and different measurement data vectors correspond to different collection times.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1) The remote synchronous measurement system and method for wind farm collector line fault monitoring of the present invention uses the second pulse signal of the global positioning system (GPS) as the synchronization signal provided to the counter module to ensure second-level time synchronization between multiple synchronous measurement units in different locations. When the second pulse signal arrives, the counter modules of multiple synchronous measurement units are reset to zero at the same time, and start nanosecond-level precise counting and synchronization. The comparison modules of multiple synchronous measurement units can trigger the corresponding A / D conversion modules to perform analog / digital conversion based on the counting results of the corresponding counter modules to ensure high synchronization of the A / D conversion results of each wind turbine box transformer branch collected. The synchronization accuracy of the synchronous measurement unit of the present invention can reach more than 10 nanoseconds. The present invention solves the problem that the current data of the wind turbine box transformer branch collected has low synchronization due to the dispersed geographical locations of the wind turbines, which cannot meet the needs of wind farm collector line fault monitoring.

[0030] 2) The remote synchronous measurement system and method of the present invention can also be used to perform high-precision synchronous measurement of electrical quantity signals of wind turbines in different wind farms. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings required for the description. Obviously, the drawings described below are one embodiment of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort:

[0032] Figure 1 Schematic diagram of wind farm;

[0033] Figure 2 Schematic diagram of a remote synchronous measurement system for wind farm collector line fault monitoring according to an embodiment of the present invention;

[0034] Figure 3 A schematic diagram of a synchronous measurement unit in an embodiment of the present invention;

[0035] Figure 4 The flowchart of the remote synchronous measurement method for wind farm collector line fault monitoring in an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0037] It will be understood that when used in this specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0038] It should also be understood that the terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit the present application. As used in this specification and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0039] It should be further understood that the term "and / or" used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0040] As used in this specification and the appended claims, the term "if" can be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "upon determination" or "in response to determining" or "upon detection of [described condition or event]" or "in response to detecting [described condition or event]," depending on the context.

[0041] In addition, in the description of the present application, the terms "first", "second", "third", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0042] To detect faults in wind farm collector lines, synchronous sampling of the electrical signals from each wind turbine is required. Typically, an A / D conversion module acquires the wind turbine's electrical signal (analog signal) and converts it into a corresponding digital signal for sampling (also known as A / D sampling). Accurately detecting short-circuit faults in the collector line requires at least 1024 A / D samples of the 50Hz power frequency signal (the wind turbine's electrical signal) within each cycle (20ms), achieving a sampling rate of 51200 SPS (samples per second).

[0043] High synchronization of electrical signal sampling across wind turbines is crucial for accurately monitoring wind farm collector line faults. This requires that the angular deviation of each wind turbine's A / D converter module at each A / D conversion moment be less than 1 minute. Given a 20ms power frequency cycle, this translates to a time deviation of less than 18µs for each A / D converter module at each conversion moment, a challenge for geographically dispersed wind turbines.

[0044] like Figure 2 As shown, a wind farm includes electrically connected collector lines and multiple wind turbines. The present invention provides a remote synchronous measurement system for monitoring faults in wind farm collector lines, comprising: multiple synchronous measurement units 1, each receiving electrical quantity signals from multiple wind turbines.

[0045] like Figure 3 As shown, the synchronous measurement unit 1 includes: a main processor 11 , a GPS module 12 , a counter module 13 , a comparison module 14 , an A / D conversion module 15 , a sampling period storage module 16 , and a wireless communication module 17 .

[0046] The main processor 11 is used to set the sampling cycle time and store it in the sampling cycle storage module 16. The sampling cycle time can be set according to actual needs and is not limited in the present invention. The main processing module can be a CPU or FPGA, which is not limited in the present invention.

[0047] The GPS module 12 is used to output a second pulse signal representing GPS time. The second pulse signal of the GPS module 12 is used to synchronize the multiple synchronous measurement units 1 with each other in the second level.

[0048] The counter module 13 is used for performing nanosecond counting and synchronization. The first count value is generated by the counter module 13. Figure 3 As shown, counter module 13 is signal-connected to GPS module 12. When counter module 13 receives the second pulse signal, it resets the first count value and restarts counting. In other words, the second pulse signal serves as a reference signal for counter module 13 to count. In this embodiment, counter module 13 includes a crystal oscillator 132 and a counter 131. Crystal oscillator 132 generates a clock signal, and counter 131 generates a first count value based on the clock signal. Generating the first count value is well known in the art. For example, the first count value increments by 1 for each cycle of the clock signal generated by crystal oscillator 132.

[0049] like Figure 3As shown, the comparison module 14 is communicatively connected to the counter module 13 and the sampling cycle storage module 16, and obtains the first count value and the sampling cycle time from the counter module 13 and the sampling cycle storage module 16, respectively. The comparison module 14 generates a corresponding count time based on the first count value. As is easy to understand, given the cycle time of the clock signal generated by the crystal oscillator 132, the count time is the product of the first count value and the cycle time of the clock signal. When the count time equals the sampling cycle time, the comparison module 14 generates a synchronous sampling pulse signal and a reset signal. When the counter module 13 receives the reset signal, it resets the first count value and restarts counting.

[0050] like Figure 3 As shown, the A / D conversion module 15 receives the electrical quantity signal from the corresponding fan and is signal-connected to the comparison module 14 and the main processor 11. In this embodiment, the A / D conversion module 15 is connected to the corresponding fan box transformer branch to receive the electrical quantity signal from the corresponding fan. The synchronous sampling pulse signal generated by the comparison module 14 triggers the A / D conversion module 15 to convert the electrical quantity signal output by the corresponding fan into the corresponding A / D conversion result, which is then provided to the main processor 11.

[0051] In one embodiment, the sampling period is 1 ms, the frequency of the crystal oscillator 132 is 100 MHz, and a sampling rate of 1 kSPS can be achieved for the electrical quantity signal output by the fan.

[0052] In one embodiment, the GPS module 12 also provides a second pulse signal to the main processor 11. The main processor 11 generates a corresponding second count value based on the number of received A / D conversion results. When the main processor 11 receives the second pulse signal, the second count value is reset and the count restarts. In other words, the second count value is used to count the number of A / D conversion results received between two adjacent second pulse signals. The main processor 11 also generates a corresponding four-tuple based on the received A / D conversion results. The four-tuple includes: the corresponding wind turbine number, the A / D conversion result, the corresponding second pulse sequence number, and the corresponding second count value. It is easy to understand that the second pulse signal and the second count value can accurately determine the acquisition time of the A / D conversion result, and the wind turbine number can uniquely identify the source of the corresponding A / D conversion result.

[0053] like Figure 3 As shown, the wireless communication module 17 is connected between the main processor 11 and the host computer 18 and is used to send the quadruple to the host computer 18.

[0054] In one embodiment, the host computer 18 generates a corresponding measurement data vector X based on the received quaternary data. t,j .in M represents the total number of fans; i represents the fan number; j represents the second count value; t represents the second pulse number; It indicates the jth A / D conversion result collected for the fan numbered i between the second pulses numbered t and t+1.

[0055] The present invention also provides a remote synchronous measurement method for wind farm collector line fault monitoring, which is applied to the remote synchronous measurement system for wind farm collector line fault monitoring as described in the present invention, such as Figure 4 As shown, the remote synchronous measurement method includes the steps of:

[0056] S1. The main processor sets the sampling cycle time and stores it in the sampling cycle storage module; the first count value is reset to zero;

[0057] S2, the counter module starts nanosecond counting and generates a first count value; if the counter module receives a second pulse signal, the first count value is reset to zero and step S2 is repeated; otherwise, the process proceeds to S3;

[0058] S3. When the counting time is equal to the sampling cycle time, the comparison module generates a synchronous sampling pulse signal and a reset signal; the synchronous sampling pulse signal triggers the A / D conversion module to convert the electrical quantity signal of the corresponding fan into the corresponding A / D conversion result, and the A / D conversion result is sent to the host computer through the main processor; the counter module resets the first count value based on the reset signal; and enters S2.

[0059] The step S3 in which the A / D conversion result is sent to the host computer via the main processor comprises the following steps:

[0060] S31, the main processor further generates a corresponding second count value based on the number of received A / D conversion results, and when the main processor receives a second pulse signal, the second count value is reset to zero and restarts counting;

[0061] S32. The main processor generates a corresponding quaternary group based on the received A / D conversion result, wherein the quaternary group includes: a corresponding wind turbine number, an A / D conversion result, a corresponding pulse-per-second signal, and a corresponding second count value;

[0062] S33. The main processor sends the quaternary group to the host computer.

[0063] In one embodiment, the host computer generates multiple measurement data vectors based on the received quaternary group. The measurement data vectors include A / D conversion results of multiple wind turbines collected at the same time. Different measurement data vectors correspond to different collection times.

[0064] The remote synchronous measurement system and method for wind farm collector line fault monitoring of the present invention uses the second pulse signal of the global positioning system (GPS) as the synchronization signal provided to the counter module to ensure second-level time synchronization between multiple synchronous measurement units 1 in different locations. When the second pulse signal arrives, the counter modules of multiple synchronous measurement units 1 are simultaneously reset to zero and start nanosecond-level precise counting and synchronization. The comparison modules of multiple synchronous measurement units 1 can simultaneously trigger the corresponding A / D conversion modules to perform analog / digital conversion based on the counting results of the corresponding counter modules to ensure high synchronization of the A / D conversion results of each wind turbine box transformer branch collected. The synchronization accuracy of the synchronous measurement unit 1 of the present invention (the same as the accuracy of the crystal oscillator 132) can reach above 10 nanoseconds. The present invention solves the problem that the current data of the wind turbine box transformer branch collected has low synchronization due to the dispersed geographical locations of the wind turbines, which cannot meet the needs of wind farm collector line fault monitoring.

[0065] Although the above embodiment describes in detail the high-precision synchronous sampling of electrical quantity signals of different wind turbines in a wind farm by multiple synchronous measurement units 1, it is easy to understand that the remote synchronous measurement system and method of the present invention can also be used to perform high-precision synchronous measurement of electrical quantity signals of wind turbines in different wind farms, which will not be described in detail here.

[0066] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0067] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and such modifications or substitutions are intended to be within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A remote synchronous measurement system for monitoring faults in a wind farm collector line, wherein the wind farm comprises an electrically connected collector line and a plurality of wind turbines, characterized in that: The remote synchronous measurement system comprises: a plurality of synchronous measurement units, each used for performing real-time synchronous measurement of electrical quantity signals of the plurality of wind turbines; The synchronous measurement unit comprises: The main processor is responsible for the overall control of the synchronous measurement unit, including setting the sampling cycle time for real-time synchronous measurement; GPS module, used to receive satellite pulse-second signals; a counter module for performing nanosecond counting and generating a first count value; the counter module signal is connected to the GPS module, and resets the first count value to zero and restarts counting based on the received second pulse signal, so as to achieve second-level synchronization between the synchronous measurement units; a comparison module connected to the counter module, generating a corresponding counting time based on the first counting value; when the counting time is equal to the sampling cycle time, the comparison module generates a synchronous sampling pulse signal and a reset signal; the counter module resets the first counting value to zero and restarts counting based on the reset signal; The A / D conversion module receives the electrical quantity signal of the corresponding fan and connects the comparison module and the main processor through digital signals. The A / D conversion module is triggered and started by the synchronous sampling pulse signal to realize the analog-to-digital conversion of the fan electrical quantity signal and provide the conversion result to the main processor.

2. The remote synchronous measurement system for wind farm collector line fault monitoring according to claim 1, characterized in that: The counter module includes: a crystal oscillator and a counter; the crystal oscillator is used to generate a clock signal, and the counter generates a first count value based on the clock signal.

3. The remote synchronous measurement system for wind farm collector line fault monitoring according to claim 1, characterized in that: It also includes a sampling cycle time storage module, whose digital signal is connected to the main processor and the comparison module, and is used to receive and store the sampling cycle time sent by the main processor and provide it to the comparison module.

4. The remote synchronous measurement system for wind farm collector line fault monitoring according to claim 1, characterized in that: The GPS module also provides a second pulse signal to the main processor; the main processor generates a corresponding second count value based on the number of received A / D conversion results. When the main processor receives the second pulse signal, the second count value is cleared and restarts counting; the main processor also generates a corresponding four-tuple based on the received A / D conversion result, and the four-tuple includes: the corresponding wind turbine number, the A / D conversion result, the corresponding second pulse sequence number, and the corresponding second count value.

5. The remote synchronous measurement system for wind farm collector line fault monitoring according to claim 4, characterized in that: It also includes a wireless communication module, which is connected between the main processor and the host computer and is used to send the quadruple to the host computer.

6. The remote synchronous measurement system for wind farm collector line fault monitoring according to claim 5, characterized in that: The host computer generates the corresponding measurement data vector X based on the received quaternion t,j ,in M represents the total number of fans; i represents the fan number; j represents the second count value; t represents the second pulse number; It indicates the jth A / D conversion result collected for the fan numbered i between the second pulses numbered t and t+1.

7. The remote synchronous measurement system for wind farm collector line fault monitoring according to claim 1, characterized in that: The main processing module uses CPU or FPGA.

8. A remote synchronous measurement method for wind farm collector line fault monitoring, applied to the remote synchronous measurement system for wind farm collector line fault monitoring according to any one of claims 1 to 7, characterized in that: The remote synchronous measurement method comprises the following steps: S1. The main processor sets the sampling cycle time and stores it in the sampling cycle storage module; the first count value is reset to zero; S2, the counter module starts nanosecond counting and generates a first count value; if the counter module receives a second pulse signal, the first count value is reset to zero and step S2 is repeated; otherwise, the process proceeds to S3; S3. When the counting time is equal to the sampling cycle time, the comparison module generates a synchronous sampling pulse signal and a reset signal; the synchronous sampling pulse signal triggers the A / D conversion module to convert the electrical quantity signal of the corresponding fan into the corresponding A / D conversion result, and the A / D conversion result is sent to the host computer through the main processor; the counter module resets the first count value based on the reset signal; and enters S2.

9. The remote synchronous measurement method for wind farm collector line fault monitoring according to claim 8, characterized in that: The step S3 in which the A / D conversion result is sent to the host computer via the main processor comprises the following steps: S31, the main processor further generates a corresponding second count value based on the number of received A / D conversion results, and when the main processor receives a second pulse signal, the second count value is reset to zero and restarts counting; S32. The main processor generates a corresponding four-tuple based on the received A / D conversion result, wherein the four-tuple includes: a corresponding wind turbine number, an A / D conversion result, a corresponding second pulse sequence number, and a corresponding second count value; S33. The main processor sends the quaternary group to the host computer.

10. The remote synchronous measurement method for wind farm collector line fault monitoring according to claim 8, characterized in that: Step S33 further includes: the host computer generates multiple measurement data vectors based on the received quaternary group, wherein the measurement data vectors include A / D conversion results of multiple wind turbines collected at the same time, and different measurement data vectors correspond to different collection times.

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