CN102508055B

CN102508055B - Device and method for detecting wind power generation grid-connected system

Info

Publication number: CN102508055B
Application number: CN201110295112.0A
Authority: CN
Inventors: 孙秋野; 张化光; 滕菲; 何志强; 郭靖; 刘振伟; 马大中; 杨珺; 刘鑫蕊
Original assignee: Northeastern University China
Current assignee: Northeastern University China
Priority date: 2011-09-29
Filing date: 2011-09-29
Publication date: 2014-05-14
Anticipated expiration: 2031-09-29
Also published as: CN102508055A

Abstract

A wind energy generation grid-connected system detection device, including a power generation unit, a storage battery unit, an inverter unit, a load simulation and simulated grid unit control unit, a control unit and a detection unit; the power generation unit includes a wind generator and a wind turbine access controller; the inverter Transformation unit includes inverter and inverter access controller; load simulation and simulated grid unit includes load selector and simulated load, grid-connected controller and simulated grid; control unit includes DSP, storage device and communication module; The detection unit includes a fan state detection mechanism and an electrical performance detection mechanism, and the battery unit includes a battery, a battery controller and a Boost circuit. The method of the invention respectively detects the island operation of the wind turbine to be tested, the grid-connected operation of the wind turbine to be tested, and the working status of the inverter to be tested when the standard wind turbine is connected to the grid, so as to realize the detection of the wind turbine or the inverter under various loads, and meet the requirements of multiple wind turbines or inverters. Switching between inverters improves detection efficiency and accuracy.

Description

A detection device and method for a wind power generation grid-connected system

技术领域 technical field

本发明属于风能发电与电气技术领域，具体涉及一种风能发电并网系统检测装置及方法。The invention belongs to the field of wind power generation and electrical technology, and in particular relates to a detection device and method for a wind power generation grid-connected system.

背景技术 Background technique

目前存在的风机检测系统是在风机运行的过程中，实现性能基本参数的采集、分析、计算风机性能参数并绘制性能曲线，并通过采集预处理的信号对风机的传递的变频调速控制的过程。风机性能试验对于成品的检验和新产品的设计开发都至关重要，特别是对于大型，特性风机以及单件，小批量而且气流特性有特殊要求的情况，性能试验尤为重要。目前，我国风机性能检测大多以手工为主，存在试验手段落后，劳动量大和实验结果不准确等缺点。此外国内外发展的最新科技风电发电检测机构不能对发电系统进行选择，只能在发生故障的时候对发电系统进行故障判断。同时检测工具只能对风力发电机和逆变器在单一负载条件下分别进行检测，没有办法检测风力发电机和逆变器在多样负载工作条件下的匹配情况。The current fan detection system is in the process of fan operation, which realizes the collection, analysis, calculation of fan performance parameters and drawing performance curves of basic performance parameters, and the process of frequency conversion and speed regulation control of fan transmission by collecting preprocessed signals . Fan performance test is very important for the inspection of finished products and the design and development of new products, especially for large-scale, characteristic fans and single-piece, small-batch and special requirements for airflow characteristics, performance test is particularly important. At present, the performance testing of wind turbines in my country is mostly done manually, which has disadvantages such as backward test methods, heavy labor and inaccurate test results. In addition, the latest technology wind power generation detection mechanism developed at home and abroad cannot select the power generation system, but can only judge the fault of the power generation system when a fault occurs. At the same time, the detection tool can only detect the wind turbine and the inverter separately under a single load condition, and there is no way to detect the matching of the wind turbine and the inverter under various load working conditions.

发明内容 Contents of the invention

针对现有技术的不足，本发明提供一种风能发电并网系统检测装置及方法。Aiming at the deficiencies of the prior art, the present invention provides a detection device and method for a wind power generation grid-connected system.

本发明的风能发电并网系统检测装置，包括发电单元，蓄电池单元，逆变单元，负载模拟和模拟电网单元控制单元，控制单元和检测单元；The wind power generation grid-connected system detection device of the present invention includes a power generation unit, a storage battery unit, an inverter unit, a load simulation and simulation grid unit control unit, a control unit and a detection unit;

发电单元包括风力发电机和风机接入控制器；The power generation unit includes a wind generator and a wind turbine access controller;

逆变单元包括逆变器和逆变器接入控制器；The inverter unit includes an inverter and an inverter access controller;

负载模拟和模拟电网单元包括负载选择器和模拟负载，并网接入控制器和模拟电网；Load simulation and simulated grid unit includes load selector and simulated load, grid-connected controller and simulated grid;

控制单元包括DSP、储存设备和通信模块；The control unit includes DSP, storage device and communication module;

检测单元包括风机状态检测机构和电气性能检测机构；The detection unit includes a fan state detection mechanism and an electrical performance detection mechanism;

蓄电池单元包括蓄电池、蓄电池控制器和Boost电路；The battery unit includes a battery, a battery controller and a Boost circuit;

装置的具体连接是：风力发电机通过风力发电机接入控制器连接至带有蓄电池控制器的蓄电池单元，风力发电机通过风力发电机接入控制器连接带有逆变器接入控制器的逆变器，逆变单元的输出经负载选择器接至模拟负载，模拟出不同检测模式下的负载，风力发电机接有风机状态检测机构，风机状态检测机构的输出连接至电气性能检测机构，电气性能检测机构与模拟电网相连，模拟电网经并网接入控制器连接至逆变单元的输出端，风力发电机接入控制器、逆变器接入控制器、负载选择器、电气性能检测机构和并网接入控制器均连至DSP的IO端口，通信模块和存储设备外接于DSP。The specific connection of the device is: the wind generator is connected to the battery unit with the battery controller through the wind generator access controller, and the wind generator is connected to the battery unit with the inverter access controller through the wind generator access controller. Inverter, the output of the inverter unit is connected to the simulated load through the load selector, and the load under different detection modes is simulated. The wind turbine is connected to the fan state detection mechanism, and the output of the fan state detection mechanism is connected to the electrical performance detection mechanism. The electrical performance testing mechanism is connected to the simulated power grid, and the simulated power grid is connected to the output terminal of the inverter unit through the grid-connected access controller. The wind turbine is connected to the controller, the inverter is connected to the controller, the load selector, and the electrical performance detection Both the organization and the grid-connected access controller are connected to the IO port of the DSP, and the communication module and the storage device are externally connected to the DSP.

所述发电单元的风机接入控制器采用多个单刀单掷开关，每个开关其中一端连接起来作为发电单元的输出端，另一端分别连接不同风力发电机。The fan connection controller of the power generation unit adopts multiple single-pole single-throw switches, one end of each switch is connected as the output end of the power generation unit, and the other end is respectively connected to different wind power generators.

所述逆变单元的逆变器接入控制器采用多个单刀单掷开关，分别位于逆变器的输入端和输出端，控制逆变器的接入，逆变器的输入端与发电单元的输出端和蓄电池单元的输出端相连，逆变器接入控制器的输出端与负载模拟和模拟电网单元相连。The inverter access controller of the inverter unit adopts a plurality of single-pole single-throw switches, which are respectively located at the input end and output end of the inverter to control the access of the inverter. The input end of the inverter and the power generation unit The output end of the inverter is connected with the output end of the storage battery unit, and the output end of the inverter access controller is connected with the load simulation and the simulation grid unit.

所述负载模拟和模拟电网单元的负载选择器包括单刀单掷开关和控制电路，采用多个单刀单掷开关并联，控制电路接于DSP输出端，控制电路输出端接于单刀单掷开关；The load selector of the load simulation and simulation grid unit includes a single-pole single-throw switch and a control circuit, and a plurality of single-pole single-throw switches are connected in parallel, the control circuit is connected to the DSP output terminal, and the control circuit output terminal is connected to the single-pole single-throw switch;

所述模拟负载包括三种连接方式：孤岛运行时风机检测的模拟负载包括串联的断路器和熔断器和三相星形连接的电容，电感，电阻阵；并网时风机检测的模拟负载包括串联的断路器和熔断器、三相六边形连接的电容、电感和电阻阵；并网时逆变器检测的模拟负载包括熔断器，断路器和三相星形连接、角接并联的电容，电感和电阻。The simulated load includes three connection modes: the simulated load detected by the wind turbine during island operation includes series circuit breakers and fuses and three-phase star-connected capacitors, inductors, and resistance arrays; the simulated load detected by the wind turbine when connected to the grid includes series Circuit breakers and fuses, three-phase hexagonal capacitors, inductors and resistor arrays; the simulated load detected by the inverter during grid connection includes fuses, circuit breakers and three-phase star-connected, delta-connected parallel capacitors, inductance and resistance.

所述模拟电网包括保护电路，稳压电路和可调电容，可调电阻，可控交流电压源，并网接入控制器采用多个单刀单掷开关并联，并网接入控制器的输入端与逆变器接入控制器输出相连，并网接入控制器输出端依次连接保护电路和稳压电路，稳压电路的三相输出端接并联后的可调电容与可调电阻，可控交流电压源接至并联后的可调电容与可调电阻的输出端，形成星形连接。The simulated power grid includes a protection circuit, a voltage stabilizing circuit, an adjustable capacitor, an adjustable resistor, and a controllable AC voltage source. It is connected to the output of the inverter access controller, and the output of the grid-connected access controller is connected to the protection circuit and the voltage stabilization circuit in turn. The AC voltage source is connected to the output terminals of the adjustable capacitor and the adjustable resistor connected in parallel to form a star connection.

所述检测单元的风机状态检测机构采用风速仪；电气性能检测机构包括电能质量分析仪和示波器。The fan state detection mechanism of the detection unit adopts an anemometer; the electrical performance detection mechanism includes a power quality analyzer and an oscilloscope.

所述蓄电池单元的蓄电池采用铅酸蓄电池，各蓄电池之间并联；蓄电池控制器包括稳压芯片、供电电源控制芯片和输出调压芯片，蓄电池连接稳压芯片输入端，稳压芯片的输出连接供电电源控制芯片的输入，输出调压芯片输入端接至供电电源控制芯片的输出；Boost电路的输入作为蓄电池单元的输入，Boost电路的输出同蓄电池控制器的输出相连，作为蓄电池单元的输出。The storage battery of the storage battery unit adopts lead-acid storage battery, and each storage battery is connected in parallel; the storage battery controller includes a voltage stabilizing chip, a power supply control chip and an output voltage regulating chip, and the storage battery is connected to the input terminal of the voltage stabilizing chip, and the output of the voltage stabilizing chip is connected to the power supply The input of the power supply control chip and the input terminal of the output voltage regulating chip are connected to the output of the power supply control chip; the input of the Boost circuit is used as the input of the battery unit, and the output of the Boost circuit is connected with the output of the battery controller as the output of the battery unit.

本发明检测方法包括：孤岛运行时待测风力发电机的工作状态检测、并网时待测风力发电机的工作状态检测和并网时待测逆变器工作状态的检测。The detection method of the present invention includes: detection of the working state of the wind power generator to be tested during isolated island operation, detection of the working state of the wind power generator to be tested when connected to the grid, and detection of the working state of the inverter to be tested when connected to the grid.

待测风力发电机孤岛运行时，风力发电机检测是在标准逆变器和稳定模拟负载条件下进行的，主要检测风力发电机发出的电能的质量，判定在孤岛运行的模式下风力发电机的工作状态，通过DSP控制负载选择器选择相应的模拟负载。此时，电网对发电系统没有影响。When the wind turbine to be tested runs in an island, the detection of the wind turbine is carried out under the condition of a standard inverter and a stable simulated load, mainly to detect the quality of the electric energy generated by the wind turbine, and to determine the performance of the wind turbine in the island operation mode. In the working state, select the corresponding analog load through the DSP control load selector. At this time, the grid has no influence on the power generation system.

孤岛运行时，待测风力发电机工作状态检测步骤如下：When the island is running, the detection steps of the working status of the wind turbine to be tested are as follows:

步骤1：风力发电机检测条件的确定：风力发电机检测系统的蓄电池单元，逆变器，变压器，负载选择器以及模拟负载的额定功率大于等于风力发电机的视在功率；Step 1: Determination of wind turbine detection conditions: the rated power of the battery unit, inverter, transformer, load selector and simulated load of the wind turbine detection system is greater than or equal to the apparent power of the wind turbine;

步骤2：进行风力发电机离网功率性能检测；Step 2: Perform off-grid power performance testing of wind turbines;

步骤2.1：通过DSP调节风速，并启动风力发电机，风机检测机构通过风速仪，电能质量分析仪和示波器采集数据，包括：线电压、线电流和风速，设定采样周期和采样频率。Step 2.1: Adjust the wind speed through DSP and start the wind turbine. The wind turbine detection mechanism collects data through anemometer, power quality analyzer and oscilloscope, including: line voltage, line current and wind speed, and set the sampling period and sampling frequency.

步骤2.2：示波器根据采集的风机线电压绘制风机电压特性曲线，并计算绘制出的风机电压特性曲线与标准的风机电压特性曲线之间的相似度。Step 2.2: The oscilloscope draws the fan voltage characteristic curve according to the collected fan line voltage, and calculates the similarity between the drawn fan voltage characteristic curve and the standard fan voltage characteristic curve.

$S S = = ((\frac{{Σ Σ}_{i i = = 11}^{n no} (({A A}_{i i} + + {B B}_{i i}))}{{Σ Σ}_{i i = = 11}^{n no} (({A A}_{i i} \times \times {B B}_{i i}))} \overset{&OverBar; &OverBar;}{U u} + + {Σ Σ}_{i i = = 11}^{n no} ln ln (({A A}_{i i}^{22} + + {B B}_{i i}^{22})) \overset{&OverBar; &OverBar;}{P P})) \times \times {Σ Σ}_{i i = = 11}^{n no} (({A A}_{i i} - - {B B}_{i i})) - - - - - - ((11))$

其中，in,

S，风机电压特性曲线相似度；S, the similarity of the fan voltage characteristic curve;

A_i，为采样得到的风机电压特性曲线上标准时间点上的电压值，A _i , is the voltage value at the standard time point on the fan voltage characteristic curve obtained by sampling,

B_i，为标准的风机电压特性曲线上标准时间点上的电压值，B _i , is the voltage value at the standard time point on the standard fan voltage characteristic curve,

为电压的平均值，

is the average value of the voltage,

为功率的平均值，

is the mean value of the power,

n，采样数据个数。n, the number of sampled data.

步骤2.2.1：对示波器采集来的数据随机采样，将采样的数据与系统存储的伏安特性标准曲线进行对比，由公式(1)算出两曲线的相似度。其中，系统对每一时钟周期内采集500个点；Step 2.2.1: Randomly sample the data collected by the oscilloscope, compare the sampled data with the standard curve of volt-ampere characteristics stored in the system, and calculate the similarity between the two curves by formula (1). Among them, the system collects 500 points in each clock cycle;

步骤2.2.2：计算所有采样周期的整体相似度S_p，即对每一采样周期的相似度取平均值：Step 2.2.2: Calculate the overall similarity S _p of all sampling periods, that is, average the similarity of each sampling period:

${S S}_{p p} = = \frac{11}{n no} {Σ Σ}_{i i = = 11}^{n no} {S S}_{i i} - - - - - - ((22))$

步骤2.2.3：计算所有采样周期的平均风速

和平均功率

Step 2.2.3: Compute the average wind speed over all sampling periods

and average power

$\overset{&OverBar; &OverBar;}{v v} = = \frac{11}{n no} {Σ Σ}_{i i = = 11}^{n no} {v v}_{i i}$ $\overset{&OverBar; &OverBar;}{P P} = = \frac{11}{n no} {Σ Σ}_{i i = = 11}^{n no} {P P}_{i i}$

步骤2.3：DSP再次调节风速，重复步骤2.2，其中，每次调节风速比上次增加1m/s的风速，风速上限为12m/s。Step 2.3: DSP adjusts the wind speed again, and repeats step 2.2, wherein each time the wind speed is adjusted, the wind speed is 1m/s higher than the last time, and the upper limit of the wind speed is 12m/s.

步骤3：在不同风速条件下，检测风机工作状态。Step 3: Check the working status of the fan under different wind speed conditions.

步骤3.1：计算风机总体风能转换效率η_con。Step 3.1: Calculate the overall wind energy conversion efficiency η _con of the fan.

${η η}_{con con} = = \frac{22 {P P}_{n no}}{ρπ ρπ {R R}^{22} {v v}_{n no}^{33}} - - - - - - ((33))$

其中：in:

P_n为风机输出的整体效率P _n is the overall efficiency of fan output

ρ为此时的空气密度ρ is the air density at this time

R为扇叶半径R is the blade radius

v_n为此时风速测量测量下的风速v _n is the wind speed measured by the wind speed measurement at this time

步骤3.2：计算采样周期内每一点的转换效率，绘制总体动态转换效率曲线。转换效率采用如下公式计算：Step 3.2: Calculate the conversion efficiency of each point in the sampling period, and draw the overall dynamic conversion efficiency curve. The conversion efficiency is calculated using the following formula:

η_n ^*＝0.8η_n+0.1η_n-1+0.05η_n-2+0.025×η_n-3+0.00625×η_n-4+0.00625×η_n-5+0.00625×η_n-6+0.00625×η_n-7 η _n ^* =0.8η _n +0.1η _n-1 +0.05η _n-2 +0.025×η _n-3 +0.00625×η n- ₄ +0.00625×η _n-5 +0.00625×η _n-6 +0.00625× ηn _-7

其中η_n ^*由存储器存储，是由该采样点前7个采样点的值计算得出的，主要是对存储的数据进行缓存和滤波处理，使得到的功率曲线更平滑，最大的减小了风机机械结构不稳定对实验处理的影响。Among them, η _n ^* is stored in the memory and is calculated from the values of the first 7 sampling points of the sampling point. It mainly caches and filters the stored data to make the obtained power curve smoother and reduce the maximum Influence of mechanical instability of fan on experimental treatment.

步骤3.3，计算孤岛条件下，风机的工作评价指标D_vi：Step 3.3, calculate the work evaluation index D _vi of the wind turbine under the island condition:

${D D.}_{vi vi} = = \frac{{η η}_{vi vi} \times \times \frac{ρ ρ}{{v v}_{i i}}}{1010} + + 22 ln ln {Σ Σ}_{i i = = 11}^{n no} Δ Δ {f f}_{i i} + + ln ln {Σ Σ}_{i i = = 11}^{n no} ((| | \overset{&OverBar; &OverBar;}{{P P}_{ni ni} - - {P P}_{Bni Bni}})) | | + + S S - - - - - - ((44))$

其中：in:

D_vi为风速在vi情况下风机的评价指标，D _vi is the evaluation index of the wind turbine under the condition of wind speed vi,

η_vi为风速在vi情况下风机的转换效率，η _vi is the conversion efficiency of the fan when the wind speed is vi,

为在采样周期内，取n个点的频率与额定频率的差的和，

In the sampling period, take the sum of the difference between the frequency of n points and the rated frequency,

为在采样周期内，取n个点的功率与额定频率的差的和，其中，P_ni表示第n个采样周期内第i个采样点的实际功率，P_Bni表示第n个采样周期内第i个采样点的标准功率。

In the sampling period, take the sum of the difference between the power of n points and the rated frequency, where P _ni represents the actual power of the i-th sampling point in the n-th sampling period, and P _Bni represents the actual power of the i-th sampling point in the n-th sampling period. The standard power of i sampling points.

步骤3.4，对不同vi下的风机的工作评价指标D_vi取平均值D。Step 3.4, take the average value D of the work evaluation index D _vi of the fan under different vi.

$D D. = = \frac{{D D.}_{v v 11} + + {D D.}_{v v 22} + + {D D.}_{v v 33} \cdot \cdot \cdot \cdot \cdot \cdot {D D.}_{vn vn - - 11} + + {D D.}_{vn vn}}{n no} - - - - - - ((55))$

步骤4，检查风机当前检测环境；Step 4, check the current detection environment of the fan;

步骤4.1，检查发电系统是否满足风机检测条件，如果满足进入下一步，如果不满足，将所得的数据视为错误数据。Step 4.1, check whether the power generation system meets the wind turbine detection conditions, if so, go to the next step, if not, treat the obtained data as error data.

步骤4.2，检查所绘制出的曲线是否存在数据突变点，如果存在，检查原因，将所得的数据保存在存储器中，以备查看。In step 4.2, check whether there is a data mutation point in the drawn curve, and if so, check the reason, and save the obtained data in the memory for viewing.

步骤5，如果D＞1，说明所检测的风机若接入发电系统，在孤岛运行的情况下无法进行正常工作；如果D＜1，说明该风力发电机适合接入发电系统，在孤岛运行的情况下能正常工作。Step 5, if D>1, it means that if the detected wind turbine is connected to the power generation system, it cannot work normally in the case of island operation; if D<1, it means that the wind turbine is suitable for connection to the power generation system can work normally.

待测风力发电机并网运行时，风力发电机检测是在标准逆变器和稳定模拟负载条件下进行的，风力发电机在并网运行下，通过DSP选择相应的模拟负载，通过构建模拟电网及并网接入控制器来模拟风力发电机在并入模拟电网时的工作状态，分析在特殊情况下风机对电网的影响，主要检测风力发电机输出的电能质量，判定在并网运行的模式下风力发电机的工作状态，此时，电网对发电系统产生影响。When the wind turbine to be tested is connected to the grid, the detection of the wind turbine is carried out under the standard inverter and stable simulated load conditions. And grid-connected access controller to simulate the working status of wind turbines when they are integrated into the simulated grid, analyze the impact of wind turbines on the grid under special circumstances, mainly detect the power quality output by wind turbines, and determine the mode of grid-connected operation Under the working state of the wind turbine, at this time, the power grid has an impact on the power generation system.

待测风力发电机接入模拟电网前，需确定检测条件，具体如下：Before the wind turbine to be tested is connected to the simulated power grid, the detection conditions need to be determined, as follows:

1.风力发电机通过的Boost电路，蓄电池，逆变器，变压器，并网接入控制器，模拟电网，负载选择器以及模拟负载的额定功率大于或等于风力发电机的视在功率。1. The rated power of the Boost circuit, battery, inverter, transformer, grid-connected controller, simulated grid, load selector and simulated load that the wind turbine passes through is greater than or equal to the apparent power of the wind turbine.

2.模拟电网的短路功率为风力发电机短路功率的50倍；50次谐波内的电压总畸变率必须低于10min平均值的5％。2. The short-circuit power of the simulated power grid is 50 times the short-circuit power of the wind turbine; the total distortion rate of the voltage within the 50th harmonic must be lower than 5% of the 10-min average value.

3.模拟电网在任意0.2s内的测量值在额定定值的±1％，并确保在检测期间电网频率不会发生变化，如果在检测结束后发现电网频率不满足要求，将检测期间的测量值和结论全部视为虚假数据。3. The measured value of the simulated power grid within any 0.2s is within ±1% of the rated value, and ensure that the power grid frequency will not change during the detection period. If the power grid frequency does not meet the requirements after the detection, the measurement during the detection period will be Values and conclusions are all treated as spurious data.

并网时，待测风力发电机工作状态的检测步骤如下：When connected to the grid, the detection steps of the working status of the wind turbine to be tested are as follows:

步骤1：确定并网检测条件。Step 1: Determine the grid-connected detection conditions.

步骤2：采集风力发电机组并网功率性能参数，设定采样周期和采样频率。Step 2: Collect the grid-connected power performance parameters of wind turbines, and set the sampling period and sampling frequency.

通过DSP将风速调节到风力发电机的额定风速，风机检测机构通过风速仪，电能质量分析仪和示波器采集参数数据，包括：线电压、线电流和风速。The wind speed is adjusted to the rated wind speed of the wind turbine through DSP, and the wind turbine detection mechanism collects parameter data through anemometer, power quality analyzer and oscilloscope, including: line voltage, line current and wind speed.

步骤3：计算每一采样周期内每一采样点的数据，包括风机输出电压、逆变器输出电压、风机输出电能频率，分别绘制出动态曲线，按下式计算数据：Step 3: Calculate the data of each sampling point in each sampling period, including the output voltage of the fan, the output voltage of the inverter, and the output power frequency of the fan, draw the dynamic curves respectively, and calculate the data according to the following formula:

Q_n ^*＝0.8Q_n+0.1Q_n-1+0.05Q_n-2+0.025×Q_n-3+0.00625×Q_n-4+0.00625×Q_n-5+0.00625×Q_n-6+0.00625×Q_n-7 Q _n ^* ＝0.8Q _n +0.1Q _n-1 +0.05Q _n-2 +0.025×Q n _- 3 +0.00625×Q n- ₄ +0.00625×Q _n-5 +0.00625×Q _n-6 +0.00625× Q _n-7

其中Q_n ^*由存储器存储，是由该时刻前7个采样周期的值共同计算得出，目的是对存储的数据进行缓存，滤波处理使得到的功率曲线更平滑，最大的减小了风机机械结构不稳定对实验处理的影响。Among them, Q _n ^* is stored in the memory, and is jointly calculated by the values of the first 7 sampling periods at this moment. The purpose is to cache the stored data, and the filtering process makes the obtained power curve smoother, and reduces the mechanical Effects of structural instability on experimental treatments.

步骤4：根据计算得出的风机输出电压、逆变器输出电压、风机输出电能频率和此时风机输出的线电流值计算风机输出功率和风机转换效率，并绘制相应动态曲线。Step 4: Calculate the fan output power and fan conversion efficiency based on the calculated fan output voltage, inverter output voltage, fan output power frequency, and fan output line current value at this time, and draw the corresponding dynamic curve.

步骤5：计算绘制出的风机输出电压曲线、逆变器输出电压曲线、风机输出电能频率曲线、风机输出功率曲线和风机转换效率曲线与相应的标准曲线的相似度S：Step 5: Calculate the similarity S between the drawn fan output voltage curve, inverter output voltage curve, fan output power frequency curve, fan output power curve, and fan conversion efficiency curve and the corresponding standard curve:

$S S = = (({Σ Σ}_{i i = = 11}^{n no} (({α α}_{i i} + + {β β}_{i i})) \times \times {Σ Σ}_{i i = = 11}^{n no} (({α α}_{i i} \times \times {β β}_{i i})) + + {Σ Σ}_{i i = = 11}^{n no} ln ln (({α α}_{i i}^{22} + + {β β}_{i i}^{22})))) \times \times {Σ Σ}_{i i = = 11}^{n no} (({α α}_{i i} - - {β β}_{i i})) - - - - - - ((66))$

其中，in,

α_i，表示所测量的实际曲线到原点之间的距离；α _i , represents the distance between the measured actual curve and the origin;

β_i，表示标准曲线到所对应的点到原点间的距离。β _i represents the distance from the standard curve to the corresponding point to the origin.

步骤5.1：对示波器采集的数据随机采样，将采样的数据与系统存储的标准曲线进行对比，使用上述公式算出两曲线的相似度。其中，系统对每一时钟周期内采集500个点，计算所有采样周期的整体相似度S_p，即对每一采样周期的相似度取平均值：Step 5.1: Randomly sample the data collected by the oscilloscope, compare the sampled data with the standard curve stored in the system, and use the above formula to calculate the similarity between the two curves. Among them, the system collects 500 points in each clock cycle, and calculates the overall similarity S _p of all sampling periods, that is, averages the similarity of each sampling period:

对每一周期的相似度取平均为整体相似度S：Take the average of the similarity of each cycle as the overall similarity S:

$S S = = \frac{{Σ Σ}_{i i}^{n no} (({S S}_{p p}))}{n no} - - - - - - ((77))$

步骤5.2：将风机输出电压曲线相似度代入上式得到整体风机输出电压相似度S_UO；将逆变器输出电压曲线相似度代入上式得到整体逆变器输出电压相似度S_UO′；将风机输出电能频率曲线相似度代入上式得到整体风机输出电能频率相似度S_f；将功率曲线相似度代入上式得到整体风机输出功率相似度S_p，将转换效率曲线相似度代入上式得到整体风机转换效率相似度S_η。Step 5.2: Substituting the similarity of the fan output voltage curve into the above formula to obtain the overall fan output voltage similarity S _UO ; substituting the inverter output voltage curve similarity into the above formula to obtain the overall inverter output voltage similarity S _UO ′; Substituting the similarity of the output power frequency curve into the above formula to obtain the frequency similarity S _f of the overall fan output power; substituting the similarity of the power curve into the above formula to obtain the similarity S _p of the overall fan output power, and substituting the similarity of the conversion efficiency curve into the above formula to obtain the overall fan Conversion efficiency similarity S _η .

步骤6：计算并网条件下，风机的工作评价指标D_G：Step 6: Calculate the work evaluation index D _G of the wind turbine under the grid-connected condition:

${D D.}_{G G} = = \frac{\frac{{S S}_{UO UO} + + {S S}_{UO UO}^{' '}}{22} + + {S S}_{F f} + + {S S}_{η η}}{33} - - - - - - ((88))$

其中：in:

D_G为风机并网的工作评价指标；D _G is the work evaluation index of wind turbine grid connection;

S_UO为风机输出电压相似度；S _UO is the similarity of fan output voltage;

S_UO′为逆变器输出电压相似度；S _UO ′ is the similarity of inverter output voltage;

S_f为风机输出电能频率相似度；S _f is the frequency similarity of the fan output power;

S_η为转换效率相似度。S _η is the conversion efficiency similarity.

步骤7：评价指标判断，如果D_G＞1，说明该风机在接入发电系统时，在并网的情况下无法进行正常工作；如果D_G＜1说明该风力发电机适合接入发电系统，在并网条件下能正常工作。Step 7: Evaluation index judgment, if D _G > 1, it means that the wind turbine cannot work normally when it is connected to the power generation system; if D _G < 1, it means that the wind turbine is suitable for connection to the power generation system, It can work normally under grid-connected conditions.

检测逆变器时，接入待测逆变器和标准风力发电机，并通过并网接入控制器接入模拟电网，此时通过DSP控制负载选择器选择相应的模拟负载。When testing the inverter, connect the inverter to be tested and the standard wind turbine, and connect to the simulated grid through the grid-connected controller. At this time, the DSP controls the load selector to select the corresponding simulated load.

并网时，待测逆变器工作状态的检测步骤如下：When connected to the grid, the detection steps for the working status of the inverter to be tested are as follows:

第1步：将风能发电单元输出电压调整至逆变器输入电压的额定值；微调负载使逆变器的输出功率为额定功率，缓慢调整风力发电机的输出电压，使其在额定值的80％～120％内变化并测量输出电压不同时逆变器输出电压。Step 1: Adjust the output voltage of the wind power generation unit to the rated value of the input voltage of the inverter; fine-tune the load to make the output power of the inverter equal to the rated power, and slowly adjust the output voltage of the wind turbine to make it 80% of the rated value % to 120% and measure the output voltage of the inverter when the output voltage is different.

第2步：将风力发电机输出电压调整至逆变器输入电压的额定电压值的80％；将示波器接至逆变器输出端进行测试；绘制逆变器输出电压与时间的曲线，计算其与存储器中的标准80％额定电压下的电压与时间曲线的相似度：Step 2: Adjust the output voltage of the wind turbine to 80% of the rated voltage value of the inverter input voltage; connect the oscilloscope to the output terminal of the inverter for testing; draw the curve of the inverter output voltage and time, and calculate its Similarity to the standard 80% rated voltage vs. time curve in memory:

$S S {((U u))}_{8080 % %} = = {Σ Σ}_{i i = = 11}^{N N} (({α α}_{i i 8080 % %} + + {β β}_{i i 8080 % %})) \times \times {Σ Σ}_{i i = = 11}^{n no} (({α α}_{i i 8080 % %} \times \times {β β}_{i i 8080 % %})) \times \times {Σ Σ}_{i i = = 11}^{n no} (({α α}_{i i 8080 % %} - - {β β}_{i i 8080 % %})) - - - - - - ((99))$

其中，in,

第3步：将风力发电机的输出电压变化为90％额定电压，计算90％额定电压相似度S(U)_90％；将风力发电机的输出电压变化为100％额定电压，计算100％额定电压电压相似度S(U)_100％；将风力发电机的输出电压变化为110％额定电压，计算110％额定电压电压相似度S(U)_110％；将风力发电机的输出电压变化为120％额定电压，计算120％额定电压电压相似度S(U)_120％。Step 3: Change the output voltage of the wind turbine to 90% of the rated voltage, and calculate the 90% rated voltage similarity S(U) _90% ; change the output voltage of the wind turbine to 100% of the rated voltage, and calculate 100% of the rated voltage Voltage similarity S(U) _100% ; change the output voltage of the wind generator to 110% rated voltage, calculate 110% rated voltage voltage similarity S(U) _110% ; change the output voltage of the wind generator to 120% % rated voltage, calculate 120% rated voltage voltage similarity S(U) _120% .

第4步：绘制风机发电在额定电压的80％～120％下，线电流与时间的曲线，采用步骤2～3同样的操作得到80％额定电压电流相似度S(I)_80％，90％额定电压电流相似度S(I)_90％；100％额定电压电流相似度S(I)_100％；110％额定电压电流相似度S(I)_110％；120％额定电压电流相似度S(I)_120％。Step 4: Draw the curve of line current and time for wind power generation at 80% to 120% of the rated voltage, and use the same operation in steps 2 to 3 to obtain 80% rated voltage and current similarity S(I) _80% , 90% Rated voltage and current similarity S (I) _90% ; 100% rated voltage and current similarity S (I) _100% ; 110% rated voltage and current similarity S (I) _110% ; 120% rated voltage and current similarity S (I) ) _120% .

${S S ((I I))}_{8080 % %} = = {Σ Σ}_{i i = = 11}^{n no} (({ϵ ϵ}_{i i 8080 % %} + + {μ μ}_{i i 8080 % %})) \times \times {Σ Σ}_{i i = = 11}^{n no} (({ϵ ϵ}_{i i 8080 % %} \times \times {μ μ}_{i i 8080 % %})) \times \times {Σ Σ}_{i i = = 11}^{n no} (({ϵ ϵ}_{i i 8080 % %} - - {μ μ}_{i i 8080 % %})) - - - - - - ((1010))$

第5步：通过示波器测量逆变器输入线电流I_DC、线电压U_DC和输出的线电流I_AC、线电压U_AC，并计算逆变器转换效率η：Step 5: Measure the inverter input line current I _DC , line voltage U _DC and output line current I _AC , line voltage U _AC through an oscilloscope, and calculate the inverter conversion efficiency η:

$η η = = \frac{{U u}_{AC AC} \times \times {I I}_{AC AC}}{{U u}_{DC DC} \times \times {I I}_{DC DC}} - - - - - - ((1111))$

第6步：将逆变器输入电压调到额定电压值，调节输出电流为额定值，连续可靠工作不少于8h；调节输出电流为125％额定值，连续可靠工作不少于1min；输入电压调到125％额定值，调节输出电流为额定值，连续可靠工作不少于连续可靠工作不少于10s。判断三种情况下逆变器工作是否正常工作。如果三种情况下均能正常工作，则逆变器带载指标为D_P＝3；两种情况下能正常工作，则带载指标D_P＝1.5；如果三种情况下均不能正常工作带载指标D_P＝0。Step 6: Adjust the input voltage of the inverter to the rated voltage value, adjust the output current to the rated value, and work continuously and reliably for no less than 8 hours; adjust the output current to 125% of the rated value, and work continuously and reliably for no less than 1 minute; input voltage Adjust to 125% of the rated value, adjust the output current to the rated value, and the continuous and reliable operation shall not be less than 10s. Judge whether the inverter is working normally under the three conditions. If it can work normally under the three conditions, the load index of the inverter is D _P = 3; if it can work normally under the two conditions, the load index D _P = 1.5; Load index D _P =0.

第7步：计算逆变器评价指标：Step 7: Calculate the inverter evaluation index:

逆变器整体相似度评价指标D_S：Inverter overall similarity evaluation index D _S :

${D D.}_{S S} = = \frac{\frac{S S {((I I))}_{8080 % %} + + S S {((U u))}_{8080 % %}}{22} + + \frac{S S {((I I))}_{9090 % %} + + S S {((U u))}_{9090 % %}}{22} + + \frac{S S {((I I))}_{100100 % %} + + S S {((U u))}_{100100 % %}}{22} + + \frac{S S {((I I))}_{110110 % %} + + S S {((U u))}_{110110 % %}}{22} + + \frac{S S {((I I))}_{120120 % %} + + S S {((U u))}_{120120 % %}}{22}}{55}$

逆变器转换效率评价指标D_η：Inverter conversion efficiency evaluation index D _η :

${D D.}_{η η} = = \frac{η η - - {η η}_{B B}}{{η η}_{B B}} - - - - - - ((1212))$

连续工作状态性能评价指标D_P如所示第6步得出。The continuous working state performance evaluation index D _P is obtained as shown in step 6.

第8步：计算逆变器总体评价指标：Step 8: Calculate the overall evaluation index of the inverter:

D_N＝D_η+D_S+LnD_P D _N ＝D _η +D _S +LnD _P

第9步：如果D_N≤1，说明逆变器适合在所接入的发电系统中并网发电。否则，逆变器不适合接入该发电系统，不能直接连入逆变单元中并网发电。Step 9: If D _N ≤ 1, it means that the inverter is suitable for grid-connected power generation in the connected power generation system. Otherwise, the inverter is not suitable for connecting to the power generation system, and cannot be directly connected to the inverter unit for grid-connected power generation.

有益效果：Beneficial effect:

(1)本发明采用分开检测的方式，首先通过风力发电机接入电路将待测风力发电机接入发电系统，并且通过逆变器接入电路将标准逆变器接入发电系统，通过采集的数据判断待测风力发电机的运行情况；然后，通过逆变器接入电路将待测逆变器接入发电系统，风力发电机接入电路将标准风力发电机接入发电系统，通过采集的数据判断待测逆变器的运行情况，通过分别判断可得出发电系统的故障的具体原因；(1) The present invention adopts the mode of separate detection. First, the wind power generator to be tested is connected to the power generation system through the wind power generator connection circuit, and the standard inverter is connected to the power generation system through the inverter connection circuit. Then, the inverter to be tested is connected to the power generation system through the inverter connection circuit, and the standard wind power generator is connected to the power generation system through the wind power generator connection circuit. Judging the operation status of the inverter to be tested based on the data, and the specific cause of the failure of the power generation system can be obtained through separate judgments;

(2)实现风力发电机在多样负载工作条件下的检测，并且检测的同时可以满足多个待测风力发电机间的切换，实现多个风力发电机发电状态的比较和检测；极大的提高了风力发电机检测的效率和准确性；(2) Realize the detection of wind turbines under various load working conditions, and at the same time, it can meet the switching between multiple wind turbines to be tested, and realize the comparison and detection of the power generation status of multiple wind turbines; greatly improve Improve the efficiency and accuracy of wind turbine detection;

(3)实现逆变器在多样负载工作条件下的检测，检测的同时可以满足多个待测逆变器间的切换，实现多个逆变器逆变工作状态的比较和检测，极大的提高了逆变器检测的效率和准确性。(3) Realize the detection of inverters under various load working conditions, and at the same time, it can meet the switching between multiple inverters to be tested, and realize the comparison and detection of the inverter working status of multiple inverters. The efficiency and accuracy of inverter detection are improved.

附图说明 Description of drawings

图1本发明实施例检测装置总体结构框图；Fig. 1 overall structural block diagram of the detection device of the embodiment of the present invention;

图2本发明实施例风机孤岛运行检测原理图；Figure 2 is a schematic diagram of the detection principle of fan island operation in the embodiment of the present invention;

图3本发明实施例风机性能检测机构原理图；Fig. 3 is a schematic diagram of the fan performance detection mechanism of the embodiment of the present invention;

图4本发明实施例孤岛运行时负载原理图；Fig. 4 is a schematic diagram of loads during island operation according to an embodiment of the present invention;

图5本发明实施例风机并网时检测原理图；Figure 5 is a schematic diagram of the detection principle when the fan is connected to the grid according to the embodiment of the present invention;

图6本发明实施例模拟电网结构原理图；Fig. 6 is a schematic diagram of a simulated power grid structure according to an embodiment of the present invention;

图7本发明实施例风机并网状态下负载原理图；Fig. 7 is a schematic diagram of the load in the grid-connected state of the wind turbine according to the embodiment of the present invention;

图8本发明实施例蓄电池的连接原理图；Fig. 8 is a schematic diagram of the connection principle of the storage battery of the embodiment of the present invention;

图9本发明实施例逆变器检测负载的连接原理图；Fig. 9 is a schematic diagram of the connection principle of the load detected by the inverter of the embodiment of the present invention;

图10本发明实施例负载选择器控制电路原理图；Fig. 10 is a schematic diagram of a load selector control circuit according to an embodiment of the present invention;

图11本发明实施例风力发电机接入控制器连接原理图；Fig. 11 is a connection schematic diagram of a wind power generator access controller according to an embodiment of the present invention;

图12本发明实施例蓄电池控制器电路原理图，其中，(a)是供电电源控制芯片原理图(b)是稳压芯片原理图(c)是输出调压芯片原理图；Fig. 12 is the schematic diagram of the battery controller circuit according to the embodiment of the present invention, wherein (a) is the schematic diagram of the power supply control chip (b) is the schematic diagram of the voltage stabilizing chip (c) is the schematic diagram of the output voltage regulating chip;

图13本发明实施例通信模块电路连接原理图。Fig. 13 is a schematic diagram of circuit connection of the communication module according to the embodiment of the present invention.

具体实施方式 Detailed ways

下面结合附图和实施例对本发明风能发电并网系统检测装置做进一步说明。The detection device for the grid-connected system of wind power generation according to the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

本发明检测系统包括发电单元，蓄电池单元，逆变单元，负载模拟和模拟电网单元控制单元，控制单元和检测单元，如图1所示；The detection system of the present invention includes a power generation unit, a storage battery unit, an inverter unit, a load simulation and simulation grid unit control unit, a control unit and a detection unit, as shown in Figure 1;

发电单元包括风力发电机和风机接入控制器，标准风力发电机的初始装机型号为SKYWING 1000W，待测风力发电机的初始装机型号为FD2.8-1.0KW76。The power generation unit includes a wind turbine and a wind turbine access controller. The initial installed model of the standard wind turbine is SKYWING 1000W, and the initial installed model of the wind turbine to be tested is FD2.8-1.0KW76.

逆变单元包括待测逆变器和逆变器接入控制器，标准逆变器的初始装机型号为KorkieK-1000W；待测逆变器的初始装机型号为FD3.0-1000。该逆变器由KCD7-11单刀单掷船形开关和DKB0保护开关组成的逆变器接入控制器连入逆变单元。The inverter unit includes the inverter to be tested and the inverter access controller. The initial installed model of the standard inverter is KorkieK-1000W; the initial installed model of the tested inverter is FD3.0-1000. The inverter is connected to the inverter unit by the inverter access controller composed of KCD7-11 SPST rocker switch and DKB0 protection switch.

控制单元包括DSP、存储设备和通信模块，DSP采用TMS320F2407A，通信模块型号MAX232与计算机相连。通信模块电路连接原理图如图13所示。存储设备由12片并联IS61LV256-15J的SRAM和12片并联的SST25VF080B-50-4C-QAF的8Mbit的SPI Flash组成。功能在于储存标准信息和存储检测系统的中间量。The control unit includes DSP, storage device and communication module. The DSP adopts TMS320F2407A, and the communication module model MAX232 is connected with the computer. The schematic diagram of the circuit connection of the communication module is shown in Figure 13. The storage device consists of 12 parallel IS61LV256-15J SRAMs and 12 parallel SST25VF080B-50-4C-QAF 8Mbit SPI Flash. The function is to store the standard information and store the intermediate quantity of the detection system.

检测单元包括风机状态检测机构和电气性能检测机构，风机性能检测机构原理图如图3所示，风机状态检测机构包括风速仪，主要进行风力发电机检测，风速仪选用+E EE65-VB5的风速传感器；电气性能检测机构由三台A，B，C相间的电能质量分析仪和三台单路输入单路输出的示波器组成。电能质量分析仪输出的信号传递给DSP中的电能质量分析单元，主要判定三相电能的稳定情况。示波器输出的信号同FLASH中存储的标准信号进行比较，通过DSP中的波形比较单元进行分析，判定三相电能的动态情况，具体搭建如图3所示。The detection unit includes a fan state detection mechanism and an electrical performance detection mechanism. The schematic diagram of the fan performance detection mechanism is shown in Figure 3. The fan state detection mechanism includes an anemometer, which mainly detects wind turbines. The anemometer uses +E EE65-VB5 wind speed Sensor; the electrical performance testing mechanism consists of three power quality analyzers between A, B, and C phases and three oscilloscopes with single input and single output. The signal output by the power quality analyzer is transmitted to the power quality analysis unit in the DSP, which mainly determines the stability of the three-phase power. The signal output by the oscilloscope is compared with the standard signal stored in the FLASH, and analyzed by the waveform comparison unit in the DSP to determine the dynamic situation of the three-phase electric energy. The specific structure is shown in Figure 3.

所述蓄电池和蓄电池控制器，蓄电池采用铅酸蓄电池，蓄电池采用6-GFM-200Ah，各蓄电池之间并联。蓄电池主要是将太阳能发电机组发出的多余电能进行储存，在电能紧缺的时候充当补充电源，平衡逆变器与发电机组的功率差。蓄电池控制器是对蓄电池状态进行控制。其中TPS787D318是供电电源控制芯片，LM7812CT是稳压芯片，IMB17是输出调压芯片，蓄电池的连接原理图如图8所示，蓄电池控制器电路原理图如图12所示。The battery and the battery controller, the battery is a lead-acid battery, the battery is 6-GFM-200Ah, and the batteries are connected in parallel. The storage battery is mainly to store the excess electric energy generated by the solar generator set, and act as a supplementary power supply when the electric energy is in short supply, and balance the power difference between the inverter and the generator set. The battery controller controls the state of the battery. Among them, TPS787D318 is the power supply control chip, LM7812CT is the voltage regulator chip, IMB17 is the output voltage regulation chip, the connection schematic diagram of the battery is shown in Figure 8, and the circuit schematic diagram of the battery controller is shown in Figure 12.

风力发电机检测和逆变器检测中的接入控制器由4块压型DNLAS4501DFT2G通用单刀单掷开关组成。风机接入控制器将其中的将每一块的一端连接起来作为输出连接到蓄电池上，另外每块的端接口分别连接到4块不同的风力发电机上，其中1，2，3，4分别与DSP中的ADCIN10，ADCIN11，ADCIN12，ADCIN13相连，连接如图11所示，逆变器接入控制器同理。The access controller in wind turbine detection and inverter detection is composed of 4 press-type DNLAS4501DFT2G general-purpose single-pole single-throw switches. The fan access controller connects one end of each block as an output to the battery, and the end interface of each block is connected to 4 different wind turbines, of which 1, 2, 3, and 4 are respectively connected to the DSP ADCIN10, ADCIN11, ADCIN12, and ADCIN13 are connected as shown in Figure 11, and the inverter is connected to the controller in the same way.

负载模拟和模拟电网单元包括负载选择器和模拟负载，并网接入控制器和模拟电网，负载选择器包括单刀单掷开关和控制电路，采用ADG1334+12V四通道单刀单掷开关阵列，控制电路接于DSP输出端，控制电路输出端接于单刀单掷开关，模拟负载包括三相断路器、三相熔断器和三相模拟负载；模拟电网结构原理图如图6所示，包括保护电路，稳压电路和可调电容，可调电阻，可控交流电压源，并网接入控制器采用多个单刀单掷开关并联，并网接入控制器的输入端与逆变器接入控制器输出相连，并网接入控制器输出端依次连接保护电路和稳压电路，稳压电路的三相输出端接并联后的可调电容与可调电阻，可控交流电压源接至并联后的可调电容与可调电阻的输出端，形成星形连接。其中可调交流电压源，可调电阻，电容有效的模拟了在不同的功率因数下电网的多种情况，增加了模拟电网的准确性。模拟负载包括三相断路器、三相熔断器和三相模拟负载。Load simulation and simulated grid unit includes load selector and simulated load, grid-connected controller and simulated grid, load selector includes SPST switch and control circuit, adopts ADG1334+12V four-channel SPST switch array, control circuit Connected to the DSP output terminal, the output terminal of the control circuit is connected to the single-pole single-throw switch, the simulated load includes a three-phase circuit breaker, a three-phase fuse and a three-phase simulated load; the schematic diagram of the simulated grid structure is shown in Figure 6, including the protection circuit, The voltage stabilizing circuit and adjustable capacitor, adjustable resistance, and controllable AC voltage source. The grid-connected access controller adopts multiple single-pole single-throw switches in parallel, and the input terminal of the grid-connected access controller and the inverter are connected to the controller. The output is connected, and connected to the grid. The output of the controller is connected to the protection circuit and the voltage stabilizing circuit in turn. The three-phase output of the voltage stabilizing circuit is connected to the adjustable capacitor and adjustable resistor connected in parallel. The output terminals of the adjustable capacitor and the adjustable resistor form a star connection. Among them, the adjustable AC voltage source, adjustable resistance, and capacitor effectively simulate various situations of the power grid under different power factors, increasing the accuracy of the simulated power grid. Simulated loads include three-phase circuit breakers, three-phase fuses, and three-phase simulated loads.

为了优化功能，对负载选择器外加以TI/SN74HCT574N为控制芯片的控制电路，其硬件连接如图10所示。K_M为1时为风力发电机检测模式，此时，K_m为0时为孤岛检测模式，K_m为1时为风力发电机并网检测模式；K_M为0时为逆变器检测模式。A0，A1，B0，B1分别接入DSP中的ADCIN06，ADCIN07，ADCIN08，ADCIN09引脚来控制接入模式。In order to optimize the function, the control circuit with TI/SN74HCT574N as the control chip is added to the load selector, and its hardware connection is shown in Figure 10. When K _M is 1, it is the wind turbine detection mode. At this time, when K _m is 0, it is the island detection mode. When K _m is 1, it is the wind turbine grid-connected detection mode; when K _M is 0, it is the inverter detection mode. . A0, A1, B0, and B1 are respectively connected to the ADCIN06, ADCIN07, ADCIN08, and ADCIN09 pins in the DSP to control the access mode.

本发明装置的具体连接是：风力发电机通过风力发电机接入控制器连接至带有蓄电池控制器的蓄电池单元；风力发电机通过风力发电机接入控制器连接带有逆变器接入控制器的逆变器，逆变单元的输出经负载选择器接至模拟负载，模拟出不同检测模式下的负载，风力发电机接有风机状态检测机构，风机状态检测机构的输出连接至电气性能检测机构，电气性能检测机构与模拟电网相连，模拟电网经并网接入控制器连接至逆变单元的输出端，风力发电机接入控制器、逆变器接入控制器、负载选择器、电气性能检测机构和并网接入控制器均连至DSP的IO端口，通信模块和存储设备外接于DSP。The specific connection of the device of the present invention is: the wind power generator is connected to the battery unit with the battery controller through the wind power generator access controller; the wind power generator is connected with the inverter access control through the wind power generator access controller The inverter of the inverter, the output of the inverter unit is connected to the simulated load through the load selector, and the load under different detection modes is simulated. The wind turbine is connected to the fan status detection mechanism, and the output of the fan status detection mechanism is connected to the electrical performance detection Mechanism, the electrical performance testing mechanism is connected to the simulated power grid, the simulated power grid is connected to the output end of the inverter unit through the grid-connected access controller, the wind turbine is connected to the controller, the inverter is connected to the controller, the load selector, the electrical Both the performance testing mechanism and the grid-connected access controller are connected to the IO port of the DSP, and the communication module and the storage device are externally connected to the DSP.

负载模拟和模拟电网单元控制单元通过负载选择器调整三种负载连接方式：孤岛运行时风机检测的负载搭建，并网运行时风机检测的负载搭建和并网时逆变器检测的负载搭建情况。The control unit of load simulation and simulation grid unit adjusts three load connection modes through the load selector: load setup for wind turbine detection during island operation, load setup for wind turbine detection during grid-connected operation, and load setup for inverter detection during grid-connected operation.

(1)孤岛运行时风机检测的模拟负载包括串联的断路器和熔断器和三相星接的电容，电感，电阻阵，具体为由可变电阻R₁～R₂，不变电阻R₃～R₆；可变电容C₁～C₃恒定电容C₄～C₆；可变电感X₁～X₃不变电感X₄～X₆共同组成，连接方式如图4所示。(1) The simulated load detected by the wind turbine during island operation includes series circuit breakers and fuses and three-phase star-connected capacitors, inductors, and resistor arrays, specifically composed of variable resistors R ₁ ~ R ₂ , constant resistors R ₃ ~ R ₆ ; variable capacitors C ₁ to C ₃ constant capacitors C ₄ to C ₆ ; variable inductances X ₁ to X ₃ constant inductances X ₄ to X ₆ together, the connection method is shown in Figure 4 .

(2)并网运行时风机检测的模拟负载包括串联的断路器和熔断器、三相六边形连接的电容、电感和电阻阵，具体为由可变电阻R₁，不变电阻R₂～R₆；可变电容C₁～C₃恒定电容C₄～C₆；可变电感X₁～X₂不变电感X₃～X₆共同组成，连接方式如图7所示。(2) The simulated load detected by the wind turbine during grid-connected operation includes circuit breakers and fuses in series, capacitors, inductors and resistor arrays connected in a three-phase hexagon, specifically composed of variable resistor R ₁ and constant resistor R ₂ ~ R ₆ ; variable capacitors C ₁ to C ₃ constant capacitors C ₄ to C ₆ ; variable inductances X ₁ to X ₂ and constant inductances X ₃ to X ₆ together, the connection method is shown in Figure 7 .

(3)并网时逆变器检测的模拟负载包括熔断器，断路器组成和三相星接，角接并联的电容，电感和电阻，R₁，X₁，C₁角接，R₂，X₂，C₂星接，具体连接如图9。(3) The simulated load detected by the inverter when connected to the grid includes fuses, circuit breakers, three-phase star connection, delta connection parallel capacitance, inductance and resistance, R ₁ , X ₁ , C ₁ delta connection, R ₂ , X ₂ , C ₂ star connection, the specific connection is shown in Figure 9.

本发明检测方法包括：孤岛运行时待测风力发电机的工作状态检测、并网时待测风力发电机的工作状态检测和并网时待测逆变器工作状态的检测。The detection method of the invention includes: detection of the working state of the wind power generator to be tested during isolated island operation, detection of the working state of the wind power generator to be tested when connected to the grid, and detection of the working state of the inverter to be tested when connected to the grid.

本实施例中，风机孤岛运行检测原理图如图2所示，所述的风力发电机孤岛系统检测方法，包括以下步骤：In this embodiment, the schematic diagram of wind turbine island operation detection is shown in Figure 2, and the wind turbine island system detection method includes the following steps:

步骤1：确定风力发电机检测条件，将待测风机和标准逆变器接入发电系统。Step 1: Determine the detection conditions of the wind turbine, and connect the wind turbine to be tested and the standard inverter to the power generation system.

步骤2：风力发电机离网功率性能检测；Step 2: Off-grid power performance detection of wind turbines;

步骤2.1：通过DSP调节风速到5m/s，并启动风力发电机，风机检测机构通过风速仪，电能质量分析仪和示波器采集数据。Step 2.1: Adjust the wind speed to 5m/s through DSP, and start the wind turbine. The wind turbine detection mechanism collects data through anemometer, power quality analyzer and oscilloscope.

$S S = = ((\frac{{Σ Σ}_{i i = = 11}^{n no} (({A A}_{i i} + + {B B}_{i i}))}{{Σ Σ}_{i i = = 11}^{n no} (({A A}_{i i} \times \times {B B}_{i i}))} \overset{&OverBar; &OverBar;}{U u} + + {Σ Σ}_{i i = = 11}^{n no} ln ln (({A A}_{i i}^{22} + + {B B}_{i i}^{22})) \overset{&OverBar; &OverBar;}{P P})) \times \times {Σ Σ}_{i i = = 11}^{n no} (({A A}_{i i} - - {B B}_{i i})) \approx \approx 0.2715 0.2715 - - - - - - ((11))$

其中，in,

为电压的平均值， is the average value of the voltage,

为功率的平均值，

is the mean value of the power,

n，采样数据个数。n, the number of sampled data.

${S S}_{p p} = = \frac{11}{n no} {Σ Σ}_{i i = = 11}^{n no} {S S}_{i i} \approx \approx 0.2634 0.2634 - - - - - - ((22))$

步骤2.2.3：计算所有采样周期的平均风速和平均功率

Step 2.2.3: Compute the average wind speed over all sampling periods and average power

$\overset{&OverBar; &OverBar;}{v v} = = \frac{11}{n no} {Σ Σ}_{i i = = 11}^{n no} {v v}_{i i} \approx \approx 5.013 5.013 m m / / s the s$ $\overset{&OverBar; &OverBar;}{P P} = = \frac{11}{n no} {Σ Σ}_{i i = = 11}^{n no} {P P}_{i i} \approx \approx 1031.54 1031.54 W W$

步骤3：在5m/s风速条件下，检测风机工作状态。Step 3: Under the condition of 5m/s wind speed, check the working status of the fan.

${η η}_{con con} = = \frac{22 {P P}_{n no}}{ρπ ρπ {R R}^{22} {v v}_{n no}^{33}} \approx \approx 82.65 82.65 % % - - - - - - ((33))$

其中：in:

P_n为风机输出的整体效率P _n is the overall efficiency of fan output

ρ为此时的空气密度ρ is the air density at this time

R为扇叶半径R is the blade radius

v_n为此时风速测量测量下的风速，即5m/sv _n is the wind speed measured by the wind speed measurement at this time, that is, 5m/s

η_n ^*＝0.8η_n+0.1η_n-1+0.05η_n-2+0.025×η_n-3+0.00625×η_n-4+0.00625×η_n-5+0.00625×η_n-6+0.00625×η_n-7≈83.24％η _n ^* =0.8η _n +0.1η _n-1 +0.05η _n-2 +0.025×η _n-3 +0.00625×η n- ₄ +0.00625×η _n-5 +0.00625×η _n-6 +0.00625× η _n-7 ≈83.24%

${D D.}_{vi vi} = = \frac{{η η}_{vi vi} \times \times \frac{ρ ρ}{{v v}_{i i}}}{1010} + + 22 ln ln {Σ Σ}_{i i = = 11}^{n no} Δ Δ {f f}_{i i} + + ln ln {Σ Σ}_{i i = = 11}^{n no} ((| | \overset{&OverBar; &OverBar;}{{P P}_{ni ni} - - {P P}_{Bni Bni}})) | | + + S S \approx \approx 0.8527 0.8527 - - - - - - ((44))$

其中：in:

为在采样周期内，取n个点的频率与额定频率的差的和，

$D D. = = \frac{{D D.}_{v v 11} + + {D D.}_{v v 22} + + {D D.}_{v v 33} \cdot \cdot \cdot \cdot \cdot \cdot {D D.}_{vn vn - - 11} + + {D D.}_{vn vn}}{n no} \approx \approx 0.8324 0.8324 - - - - - - ((55))$

步骤4，检查风机当前检测环境，是否满足进入下一步的要求。Step 4, check whether the current detection environment of the fan meets the requirements for entering the next step.

步骤5，D＜1，说明该风力发电机适合接入发电系统，在孤岛运行的情况下能正常工作。Step 5, D<1, it means that the wind turbine is suitable for connecting to the power generation system and can work normally in the case of island operation.

风机并网时检测原理图如图5所示，并网状态下，待测风力发电机并网工作状态的检测按如下步骤进行：The schematic diagram of the detection when the wind turbine is connected to the grid is shown in Figure 5. In the grid-connected state, the detection of the grid-connected working status of the wind turbine to be tested is carried out as follows:

步骤1：确定并网检测条件，将待测风机和标准逆变器接入发电系统。Step 1: Determine the grid-connected detection conditions, and connect the wind turbine to be tested and the standard inverter to the power generation system.

步骤2：采集风力发电机组并网功率性能参数，设定采样周期为1μs和采样频率500HZ。Step 2: Collect the grid-connected power performance parameters of wind turbines, set the sampling period to 1μs and the sampling frequency to 500HZ.

通过DSP将风速调节到风力发电机的额定风速，风机检测机构通过风速仪，电能质量分析仪和示波器采集参数数据。The wind speed is adjusted to the rated wind speed of the wind turbine through DSP, and the wind turbine detection mechanism collects parameter data through anemometer, power quality analyzer and oscilloscope.

步骤3：计算每一采样周期内每一采样点的数据，包括风机输出电压、逆变器输出电压、风机输出电能频率，分别绘制出动态曲线，按下式计算数据：Q_n ^*＝0.8Q_n+0.1Q_n-1+0.05Q_n-2+0.025×Q_n-3+0.00625×Q_n-4+0.00625×Q_n-5+0.00625×Q_n-6+0.00625×Q_n-7其中Q_n ^*由存储器存储，是由该时刻前7个采样周期的值共同计算得出，目的是对存储的数据进行缓存，滤波处理使得到的功率曲线更平滑，最大的减小了风机机械结构不稳定对实验处理的影响。Step 3: Calculate the data of each sampling point in each sampling period, including the output voltage of the fan, the output voltage of the inverter, and the output power frequency of the fan, draw the dynamic curves respectively, and calculate the data according to the following formula: Q _n ^* ＝0.8Q _n +0.1Q _n-1 +0.05Q _n-2 +0.025×Q _n- ₃ +0.00625×Q _{n-4 +0.00625×Q n-5} +0.00625×Q _n-6 +0.00625×Q _n-7 where Q _n ^* is stored in the memory and is jointly calculated from the values of the first 7 sampling periods at this moment. The purpose is to cache the stored data. The filtering process makes the obtained power curve smoother and minimizes the mechanical structure of the fan. Effect of stabilization on experimental treatments.

其中，in,

$S S = = \frac{{Σ Σ}_{i i}^{n no} (({S S}_{p p}))}{n no} - - - - - - ((77))$

步骤5.2：将风机输出电压曲线相似度代入上式得到整体风机输出电压相似度S_UO≈0.8725；将逆变器输出电压曲线相似度代入上式得到整体逆变器输出电压相似度S_UO′≈0.8636；将风机输出电能频率曲线相似度代入上式得到整体风机输出电能频率相似度S_f≈0.6714；将功率曲线相似度代入上式得到整体风机输出功率相似度S_p≈1.0371，将转换效率曲线相似度代入上式得到整体风机转换效率相似度S_η≈0.5638。Step 5.2: Substituting the similarity of the fan output voltage curve into the above formula to obtain the overall fan output voltage similarity S _UO ≈ 0.8725; substituting the inverter output voltage curve similarity into the above formula to obtain the overall inverter output voltage similarity S _UO ′≈ 0.8636; substituting the similarity of fan output power frequency curve into the above formula to get the overall fan output power frequency similarity S _f ≈ 0.6714; substituting the power curve similarity into the above formula to get the overall fan output power similarity S _p ≈ 1.0371, and converting the conversion efficiency curve The similarity is substituted into the above formula to obtain the similarity S _η ≈ 0.5638 of the overall fan conversion efficiency.

${D D.}_{G G} = = \frac{\frac{{S S}_{UO UO} + + {S S}_{UO UO}^{' '}}{22} + + {S S}_{F f} + + {S S}_{η η}}{33} \approx \approx 0.8017 0.8017 - - - - - - ((88))$

其中：in:

S_η为转换效率相似度。S _η is the conversion efficiency similarity.

步骤7：D_G＜1说明该风力发电机适合接入发电系统，在并网条件下能正常工作。Step 7: D _G < 1 indicates that the wind turbine is suitable for connecting to the power generation system and can work normally under grid-connected conditions.

第1步：将风能发电单元输出电压调整至逆变器输入电压的额定值约12V；微调负载使逆变器的输出功率为额定功率约1000W，缓慢调整风力发电机的输出电压约380V，使其在额定值的80％～120％内变化并测量输出电压不同时逆变器输出电压。Step 1: Adjust the output voltage of the wind power generation unit to the rated value of the inverter input voltage of about 12V; fine-tune the load so that the output power of the inverter is about 1000W, and slowly adjust the output voltage of the wind generator to about 380V, so that It varies from 80% to 120% of the rated value and measures the output voltage of the inverter when the output voltage is different.

$S S {((U u))}_{8080 % %} = = {Σ Σ}_{i i = = 11}^{N N} (({α α}_{i i 8080 % %} + + {β β}_{i i 8080 % %})) \times \times {Σ Σ}_{i i = = 11}^{n no} (({α α}_{i i 8080 % %} \times \times {β β}_{i i 8080 % %})) \times \times {Σ Σ}_{i i = = 11}^{n no} (({α α}_{i i 8080 % %} - - {β β}_{i i 8080 % %})) \approx \approx 0.8359 0.8359 - - - - - - ((99))$

其中，in,

第3步：将风力发电机的输出电压变化为90％额定电压，计算90％额定电压相似度S(U)_90％≈0.8721；将风力发电机的输出电压变化为100％额定电压，计算100％额定电压电压相似度S(U)_100％≈0.7935；将风力发电机的输出电压变化为110％额定电压，计算110％额定电压电压相似度S(U)_110％≈0.8036；将风力发电机的输出电压变化为120％额定电压，计算120％额定电压电压相似度S(U)_120％≈0.8148。Step 3: Change the output voltage of the wind turbine to 90% of the rated voltage, calculate the 90% rated voltage similarity S(U) _90% ≈ 0.8721; change the output voltage of the wind turbine to 100% of the rated voltage, calculate 100 % rated voltage voltage similarity S(U) _100% ≈0.7935; change the output voltage of the wind turbine to 110% rated voltage, calculate the 110% rated voltage voltage similarity S(U) _110% ≈0.8036; The output voltage change is 120% of the rated voltage, and the calculated 120% rated voltage voltage similarity S(U) _120% ≈ 0.8148.

第4步：绘制风机发电在额定电压的80％～120％下，线电流与时间的曲线，采用步骤2～3同样的操作得到80％额定电压电流相似度S(I)_80％≈0.6398，90％额定电压电流相似度S(I)_90％≈0.7025；100％额定电压电流相似度S(I)_100％≈0.7135；110％额定电压电流相似度S(I)_110％≈0.6991；120％额定电压电流相似度S(I)_120％≈0.7183。Step 4: Draw the curve of line current and time for wind power generation at 80% to 120% of the rated voltage, and use the same operation in steps 2 to 3 to obtain 80% rated voltage and current similarity S(I) _80% ≈ 0.6398, 90% rated voltage and current similarity S(I) _90% ≈0.7025; 100% rated voltage and current similarity S(I) _100% ≈0.7135; 110% rated voltage and current similarity S(I) _110% ≈0.6991; 120% Rated voltage and current similarity S(I) _120% ≈0.7183.

$η η = = \frac{{U u}_{AC AC} \times \times {I I}_{AC AC}}{{U u}_{DC DC} \times \times {I I}_{DC DC}} \approx \approx 83.12 83.12 % % - - - - - - ((1111))$

第6步：将逆变器输入电压调到额定电压值，调节输出电流为额定值，连续可靠工作不少于8h；调节输出电流为125％额定值，连续可靠工作不少于1min；输入电压调到125％额定值，调节输出电流为额定值，连续可靠工作不少于连续可靠工作不少于10s。判断三种情况下逆变器工作是否正常工作。如果三种情况下均能正常工作，则逆变器带载指标为D_P＝3；Step 6: Adjust the input voltage of the inverter to the rated voltage value, adjust the output current to the rated value, and work continuously and reliably for no less than 8 hours; adjust the output current to 125% of the rated value, and work continuously and reliably for no less than 1 minute; input voltage Adjust to 125% of the rated value, adjust the output current to the rated value, and the continuous and reliable operation shall not be less than 10s. Judge whether the inverter is working normally under the three conditions. If all three situations can work normally, the load index of the inverter is D _P =3;

${D D.}_{S S} = = \frac{\frac{S S {((I I))}_{8080 % %} + + S S {((U u))}_{8080 % %}}{22} + + \frac{S S {((I I))}_{9090 % %} + + S S {((U u))}_{9090 % %}}{22} + + \frac{S S {((I I))}_{100100 % %} + + S S {((U u))}_{100100 % %}}{22} + + \frac{S S {((I I))}_{110110 % %} + + S S {((U u))}_{110110 % %}}{22} + + \frac{S S {((I I))}_{120120 % %} + + S S {((U u))}_{120120 % %}}{22}}{55} \approx \approx 0.7593 0.7593$

${D D.}_{η η} = = \frac{η η - - {η η}_{B B}}{{η η}_{B B}} \approx \approx 0.2154 0.2154 - - - - - - ((1212))$

D_N＝D_η+D_S+LnD_P＝2.0733D _N ＝D _η +D _S +LnD _P ＝2.0733

第9步：如果D_N≥1说明逆变器不适合接入该发电系统，不能直接连入逆变单元中并网发电。Step 9: If D _N ≥ 1, it means that the inverter is not suitable for connecting to the power generation system, and cannot be directly connected to the inverter unit for grid-connected power generation.

Claims

1. The utility model provides a wind power generation grid-connected system detection device which characterized in that: the system comprises a power generation unit, a storage battery unit, an inversion unit, a load simulation and simulation power grid unit, a control unit and a detection unit;

the power generation unit comprises a wind driven generator and a fan access controller;

the inversion unit comprises an inverter and an inverter access controller;

the load simulation and simulation power grid unit comprises a load selector, a simulation load, a grid-connected access controller and a simulation power grid;

the control unit comprises a DSP, a storage device and a communication module;

the detection unit comprises a fan state detection mechanism and an electrical performance detection mechanism;

the storage battery unit comprises a storage battery, a storage battery controller and a Boost circuit;

the specific connections of the device are as follows: the wind driven generator is connected to a storage battery unit with a storage battery controller through a wind driven generator access controller, the wind driven generator is connected to an inverter with an inverter access controller through the wind driven generator access controller, the output of an inversion unit is connected to a simulation load through a load selector to simulate the load in different detection modes, the wind driven generator is connected with a fan state detection mechanism, the output of the fan state detection mechanism is connected to an electrical performance detection mechanism, the electrical performance detection mechanism is connected with a simulation power grid, the simulation power grid is connected to the output end of the inversion unit through a grid-connected access controller, the wind driven generator access controller, the inverter access controller, the load selector, the electrical performance detection mechanism and the grid-connected access controller are all connected to an IO port of a DSP, and a communication module and a storage device are externally connected to the.

2. The wind power generation grid-connected system detection device according to claim 1, characterized in that: the fan access controller of the power generation unit adopts a plurality of single-pole single-throw switches, one end of each switch is connected to serve as the output end of the power generation unit, and the other end of each switch is connected with different wind driven generators.

3. The wind power generation grid-connected system detection device according to claim 1, characterized in that: the inverter access controller of the inversion unit adopts a plurality of single-pole single-throw switches which are respectively positioned at the input end and the output end of the inverter to control the access of the inverter, the input end of the inverter is connected with the output end of the power generation unit and the output end of the storage battery unit, and the output end of the inverter access controller is connected with the load simulation and simulation power grid unit.

4. The wind power generation grid-connected system detection device according to claim 1, characterized in that: the load selector of the load simulation and simulation power grid unit comprises single-pole single-throw switches and a control circuit, the single-pole single-throw switches are connected in parallel, the control circuit is connected with the output end of a DSP (digital signal processor), the output end of the control circuit is connected with the single-pole single-throw switches, and the simulation load comprises three types: the simulation load for detecting the fan in the island operation comprises a circuit breaker and a fuse which are connected in series, and a capacitor, an inductor and a resistor array which are connected in a three-phase star shape; the simulation load detected by the fan during grid connection comprises a circuit breaker and a fuse connected in series, and a capacitor, an inductor and a resistor array connected in a three-phase hexagonal manner; the analog load detected by the inverter during grid connection comprises a fuse, a circuit breaker, a three-phase capacitor, an inductor and a resistor, wherein the capacitor, the inductor and the resistor are connected in star connection and in angular connection in parallel; the analog power grid comprises a protection circuit, a voltage stabilizing circuit, an adjustable capacitor, an adjustable resistor and a controllable alternating current voltage source, a grid-connected access controller adopts a plurality of single-pole single-throw switches to be connected in parallel, the input end of the grid-connected access controller is connected with the output end of an inverter access controller, the output end of the grid-connected access controller is sequentially connected with the protection circuit and the voltage stabilizing circuit, the three-phase output end of the voltage stabilizing circuit is connected with the adjustable capacitor and the adjustable resistor which are connected in parallel, and the controllable alternating current voltage source is connected to the output ends of the adjustable capacitor and the.

5. The wind power generation grid-connected system detection device according to claim 1, characterized in that: a fan state detection mechanism of the detection unit adopts an anemometer; the electric performance detection mechanism comprises a power quality analyzer and an oscilloscope.

6. The wind power generation grid-connected system detection device according to claim 1, characterized in that: the storage batteries of the storage battery unit adopt lead-acid storage batteries, and the storage batteries are connected in parallel; the storage battery controller comprises a voltage stabilizing chip, a power supply control chip and an output voltage regulating chip, the storage battery is connected with the input end of the voltage stabilizing chip, the output of the voltage stabilizing chip is connected with the input of the power supply control chip, and the input end of the output voltage regulating chip is connected with the output of the power supply control chip; the input of the Boost circuit is used as the input of the storage battery unit, and the output of the Boost circuit is connected with the output of the storage battery controller and used as the output of the storage battery unit.

7. The detection method of the wind power generation grid-connected system detection device according to claim 1, characterized in that: the method comprises the following steps: detecting the working state of a wind driven generator to be detected during island operation, detecting the working state of the wind driven generator to be detected during grid connection and detecting the working state of an inverter to be detected during grid connection;

when the island is operated, the working state detection steps of the wind driven generator to be detected are as follows:

step 1: determination of wind turbine detection conditions: the rated power of a storage battery unit, an inverter, a transformer, a load selector and a simulation load of the wind driven generator detection system is more than or equal to the apparent power of the wind driven generator;

step 2: detecting the off-grid power performance of the wind driven generator;

step 2.1: adjust wind speed through DSP to start aerogenerator, fan state detection mechanism passes through anemograph, electric energy quality analysis appearance and oscilloscope data acquisition, includes: setting a sampling period and a sampling frequency according to line voltage, line current and wind speed;

step 2.2: the oscilloscope draws a fan voltage characteristic curve according to the collected fan line voltage, and calculates the similarity between the drawn fan voltage characteristic curve and a standard fan voltage characteristic curve;

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wherein,

S₁similarity of voltage characteristic curves of the fans;

A_ithe voltage value at the standard time point on the fan voltage characteristic curve obtained by sampling,

B_ithe voltage value at the standard time point on the standard fan voltage characteristic curve,

is the average value of the voltage and is,

is the average value of the power and is,

n, the number of sampling periods;

step 2.2.1: randomly sampling data acquired by an oscilloscope, comparing the sampled data with a volt-ampere characteristic standard curve stored in a system, and calculating the similarity of the two curves by a formula (1), wherein the system acquires 500 points in each clock period;

step 2.2.2: calculating the overall similarity S of all sampling periods_pThat is, the similarity of each sampling period is summed and then averaged:

step 2.2.3: calculating the average of all sampling periodsWind speed

And average power

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Step 2.3: the DSP regulates the wind speed again, and the step 2.2 is repeated, wherein the wind speed is increased by 1m/s in the last time when the wind speed ratio is regulated each time, and the upper limit of the wind speed is 12 m/s;

and step 3: detecting the working state of the fan under different wind speeds;

step 3.1: calculating the total wind energy conversion efficiency eta of the fan_con；

Wherein:

P_nfor the overall efficiency of the fan output

ρ is the air density at that time

R is the radius of the fan blade

v_nFor the wind speed measured at that time

Step 3.2: calculating the conversion efficiency of each point in the sampling period, drawing a total dynamic conversion efficiency curve, wherein the conversion efficiency is calculated by adopting the following formula:

η_n ^*＝0.8η_n+0.1η_n-1+0.05η_n-2+0.025×η_n-3+0.00625×η_n-4+0.00625×η_n-5+0.00625×η_n-6+0.00625×η_n-7

wherein eta_n ^*The power curve is stored by a memory, is calculated by values of the first 7 sampling points of the sampling points, and is mainly subjected to caching and filtering processing on the stored data, so that the obtained power curve is smoother, and the influence of instability of a mechanical structure of the fan on experimental processing is reduced to the maximum extent;

step 3.3, calculating the work evaluation index D of the fan under the island condition_vi：

<math> <mrow> <msub> <mi>D</mi> <mi>vi</mi> </msub> <mo>=</mo> <mfrac> <mrow> <msub> <mi>η</mi> <mi>vi</mi> </msub> <mo>×</mo> <mfrac> <mi>ρ</mi> <msub> <mi>v</mi> <mi>i</mi> </msub> </mfrac> </mrow> <mn>10</mn> </mfrac> <mo>+</mo> <mn>2</mn> <mi>ln</mi> <munderover> <mi>Σ</mi> <mrow> <mi>i</mi> <mo>=</mo> <mn>1</mn> </mrow> <mi>n</mi> </munderover> <mi>Δ</mi> <msub> <mi>f</mi> <mi>i</mi> </msub> <mo>+</mo> <mi>ln</mi> <munderover> <mi>Σ</mi> <mrow> <mi>i</mi> <mo>=</mo> <mn>1</mn> </mrow> <mi>n</mi> </munderover> <mrow> <mo>(</mo> <mo>|</mo> <mover> <mrow> <msub> <mi>P</mi> <mi>ni</mi> </msub> <mo>-</mo> <msub> <mi>P</mi> <mi>Bni</mi> </msub> </mrow> <mo>&OverBar;</mo> </mover> <mo>)</mo> </mrow> <mo>|</mo> <mo>+</mo> <msub> <mi>S</mi> <mn>1</mn> </msub> <mo>-</mo> <mo>-</mo> <mo>-</mo> <mrow> <mo>(</mo> <mn>4</mn> <mo>)</mo> </mrow> </mrow> </math>

Wherein:

D_vithe evaluation index of the fan under the condition of vi wind speed,

η_vifor the wind speed at vi the conversion efficiency of the fan,

in order to take the sum of the differences of the frequencies of n points and the rated frequency in the sampling period,

in order to sum the difference between the power and the rated frequency at n points in a sampling period, wherein P_niRepresenting the actual power, P, of the ith sample point in the nth sample period_BniRepresenting the standard power of the ith sampling point in the nth sampling period;

step 3.4, evaluating the work indexes D of the fans under different vi_viTaking an average value D;

step 4, checking the current detection environment of the fan;

step 4.1, checking whether the power generation system meets the fan detection condition, entering the next step if the power generation system meets the fan detection condition, and regarding the obtained data as error data if the power generation system does not meet the fan detection condition;

step 4.2, checking whether the drawn curve has data mutation points, if so, checking reasons, and storing the obtained data in a memory for checking;

step 5, if D is larger than 1, the detected fan cannot work normally under the condition of island operation if the detected fan is connected to a power generation system; if D <1, the wind driven generator is suitable for being connected into a power generation system and can normally work under the condition of island operation;

the detection method of the working state of the wind driven generator to be detected during grid connection comprises the following steps:

step 1: determining grid connection detection conditions;

step 2: collecting grid-connected power performance parameters of the wind generating set, and setting a sampling period and sampling frequency;

adjust the rated wind speed of aerogenerator to through DSP, fan state detection mechanism passes through the anemoscope, and electric energy quality analyzer and oscilloscope gather parameter data, include: line voltage, line current, and wind speed;

and step 3: calculating data of each sampling point in each sampling period, wherein the data comprises fan output voltage, inverter output voltage and fan output electric energy frequency, and respectively drawing a dynamic curve;

and 4, step 4: calculating the output power and the conversion efficiency of the fan according to the calculated output voltage of the fan, the output voltage of the inverter, the output electric energy frequency of the fan and the line current value output by the fan at the moment, and drawing a corresponding dynamic curve;

and 5: calculating the similarity S between the drawn fan output voltage curve, inverter output voltage curve, fan output electric energy frequency curve, fan output power curve and fan conversion efficiency curve and the corresponding standard curve₂：

Wherein,

α_irepresenting the distance between the measured actual curve to the origin;

β_irepresenting the distance between the corresponding point of the standard curve and the origin;

step 5.1: randomly sampling data collected by oscilloscope, and storing the sampled data with systemComparing the stored standard curves, and calculating the similarity of the two curves, wherein the system collects 500 points in each clock cycle and calculates the similarity S of each cycle_pSimilarity obtained for data in each sampling period:

the obtained similarity summation and average of each sampling period is the overall similarity S₃：

Step 5.2: substituting the similarity of the fan output voltage curve into formula (7) to obtain the similarity S of the integral fan output voltage_UO(ii) a Substituting the similarity of the output voltage curve of the inverter into the above formula to obtain the similarity S of the output voltage of the whole inverter_UO'; substituting the fan output electric energy frequency curve similarity into the above formula to obtain the integral fan output electric energy frequency similarity S_f(ii) a Substituting the power curve similarity into the formula to obtain the overall fan output power similarity S'_pSubstituting the conversion efficiency curve similarity into the formula to obtain the overall fan conversion efficiency similarity S_η；

Step 6: calculating the work evaluation index D of the fan under the condition of grid connection_G：

Wherein:

D_Gthe working evaluation index is the fan grid-connected work evaluation index;

S_UOoutputting voltage similarity for the fan;

S_UO' is inverter output voltage similarity;

S_foutputting the electric energy frequency similarity for the fan;

S_ηto conversion efficiency similarity;

and 7: evaluation index judgment, if D_G>1, when the fan is connected to a power generation system, the fan cannot normally work under the condition of grid connection; if D is_G<1, the wind driven generator is suitable for being connected into a power generation system and can normally work under the condition of grid connection;

the detection steps of the working state of the inverter to be detected during grid connection are as follows:

step 1: adjusting the output voltage of the wind power generation unit to a rated value of the input voltage of the inverter; finely adjusting the load to enable the output power of the inverter to be rated power, and slowly adjusting the output voltage of the wind driven generator to enable the output voltage to change within 80% -120% of the rated power and measure that the output voltage is different from the output voltage;

step 2: adjusting the output voltage of the wind driven generator to 80% of the rated voltage value of the input voltage of the inverter; connecting an oscilloscope to the output end of the inverter for testing; and (3) drawing a curve of the output voltage of the inverter and the time, and calculating the similarity of the curve and the voltage of the standard 80% rated voltage in the memory:

and 3, step 3: changing the output voltage of the wind power generator into 90% rated voltage, calculating the similarity of 90% rated voltage S (U)_90%(ii) a Changing the output voltage of the wind power generator into 100% rated voltage, calculating 100% rated voltage similarity S (U)_100%(ii) a Changing the output voltage of the wind power generator into 110% rated voltage, calculating the 110% rated voltage similarity S (U)_110%(ii) a Changing the output voltage of the wind power generator into 120% rated voltage, calculating the similarity of the 120% rated voltage and the voltage S (U)_120%；

And 4, step 4: drawing a curve of line current and time when the power generation of the fan is 80% -120% of the rated voltage, and obtaining the 80% rated voltage current similarity S (I) by adopting the same operations of the steps 2-3_80%90% nominal voltage current similarity S (I)_90%(ii) a 100% rated voltage current similarity S (I)_100%(ii) a 110% rated voltage current similarity S (I)_110%(ii) a 120% nominal voltage current similarity S (I)_120%；

And 5, step 5: measuring inverter input line current I by oscilloscope_DCLine voltage U_DCAnd the line current I of the output_ACLine voltage U_ACAnd calculating the inverter conversion efficiency eta:

and 6, step 6: regulating the input voltage of the inverter to a rated voltage value, regulating the output current to the rated value, and continuously and reliably working for not less than 8 h; regulating the output current to 125% rated value, and continuously and reliably working for not less than 1 min; the input voltage is regulated to 125% of rated value, the output current is regulated to the rated value, and the continuous reliable work is not less than 10 s; judging whether the inverter works normally under three conditions: if the inverter can normally work under three conditions, the inverter has a load index D_P3; under two conditions, the device can work normally, and then the loading index D is obtained_P1.5; if the load index D can not work normally under three conditions_P＝0；

And 7, step 7: calculating an inverter evaluation index:

evaluation index D of overall similarity of inverter_S：

D_{S} = \frac{\frac{S {(I)}_{80 %} + S {(U)}_{80 %}}{2} + \frac{{S (I)}_{90 %} + S {(U)}_{90 %}}{2} + \frac{{S (I)}_{100 %} + {S (U)}_{100 %}}{2} + \frac{{S (I)}_{110 %} + {S (U)}_{110 %}}{2} + \frac{{S (I)}_{120 %} + S {(U)}_{120 %}}{2}}{5}

Inverter conversion efficiency evaluation index D_η：

Continuous working state performance evaluation index D_PAs shown in step 6;

and 8, step 8: calculating the overall evaluation index of the inverter:

D_N＝D_η+D_S+LnD_P

step 9: if D is_NThe condition that the inverter is suitable for grid-connected power generation in the connected power generation system is less than or equal to 1; otherwise, the inverter is not suitable for being connected into the power generation system and cannot be directly connected into the power generation systemAnd connecting the power generation grid into an inversion unit for grid-connected power generation.