CN105158341B - Transformer winding material discrimination method based on the velocity of sound - Google Patents
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- 238000004804 winding Methods 0.000 title claims abstract description 59
- 239000000463 material Substances 0.000 title claims abstract description 30
- 238000012850 discrimination method Methods 0.000 title 1
- 238000000034 method Methods 0.000 claims abstract description 13
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 abstract description 15
- 229910052802 copper Inorganic materials 0.000 abstract description 15
- 239000010949 copper Substances 0.000 abstract description 15
- 238000009413 insulation Methods 0.000 abstract description 5
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 16
- 229910052782 aluminium Inorganic materials 0.000 description 16
- 238000012360 testing method Methods 0.000 description 12
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Abstract
本发明公开了一种基于声速的变压器绕组材质鉴别方法，该方法具体包括以下步骤：S1.利用激振器在变压器绕组首端产生可听声波；S2.安装在变压器绕组首末两端的声音传感器分别接收声波信号；S3.声音传感器采集到的信号接入示波器，两波形首波时间差即为声波传播时间；利用公式v＝L/t计算声波传播速度，其中，v为声速；L为声波传播距离；t为声波传播时间；S4.将计算获得的声波传播速度与已知声波传播速度鉴别变压器绕组的材质。本发明在不破坏绕组绝缘的情况下，可以简单快捷地进行变压器绕组材质是否为铜材质的鉴别。
The invention discloses a method for identifying materials of transformer windings based on sound velocity. The method specifically includes the following steps: S1. using an exciter to generate audible sound waves at the head end of the transformer winding; S2. installing sound sensors at the first and last ends of the transformer winding Respectively receive the sound wave signal; S3. The signal collected by the sound sensor is connected to the oscilloscope, and the time difference of the first wave of the two waveforms is the sound wave propagation time; the sound wave propagation speed is calculated by using the formula v=L/t, wherein, v is the sound speed; L is the sound wave propagation Distance; t is the sound wave propagation time; S4. Identify the material of the transformer winding by comparing the calculated sound wave propagation speed with the known sound wave propagation speed. The invention can simply and quickly identify whether the material of the transformer winding is copper without damaging the insulation of the winding.
Description
技术领域technical field
本发明涉及变压器检测领域，特别涉及一种基于声速的变压器绕组材质鉴别方法。The invention relates to the field of transformer detection, in particular to a method for identifying materials of transformer windings based on sound velocity.
背景技术Background technique
电力变压器，尤其是10kV级别的配电变压器中，长期存在着使用铝线代替铜线的现象。特别是近年来，由于国内外铜价居高不下，铝绕组变压器的数量呈现大幅度增加的趋势。我国现行国标未对变压器绕组的材质做出限定，但要求若使用铝绕组需在变压器型号上明确标识。目前市面上存在的铝绕组变压器绝大部分则属于生产厂家为了节省成本将绕组由铜线偷换为铝线的情况，电力用户在购买和运行时并不知情。In power transformers, especially 10kV distribution transformers, there has been a long-term phenomenon of using aluminum wires instead of copper wires. Especially in recent years, due to high copper prices at home and abroad, the number of aluminum winding transformers has shown a trend of substantial increase. my country's current national standard does not limit the material of transformer windings, but requires that if aluminum windings are used, they must be clearly marked on the transformer model. At present, most of the aluminum winding transformers on the market belong to the situation that the manufacturers have secretly replaced the windings from copper wires to aluminum wires in order to save costs, and power users do not know when purchasing and operating.
由于铜铝材质特性上的差异，铝绕组变压器本身存在着性能上的不足。同时变压器生产企业数量巨大，许多不具备质量控制和试验检测等必要能力的小企业混迹其中，其生产的铝绕组变压器质量更是难以保证。根据国家电网公司变压器类设备事故统计分析表明：变压器绕组是变压器损坏事故的主要损坏部位，超过总损坏事故的70％，其中绕组抗短路强度不够和绝缘有缺陷是损坏事故的主要原因。由事故分析可见，变压器绕组的质量问题极易引起安全事故，使用现有的铝绕组变压器将极大地增加变压器损坏的风险，在整个电力系统运行中埋下安全隐患。因此必须加强变压器绕组的质量控制，甄别出电力系统中以次充好的铝绕组变压器。Due to the difference in the characteristics of copper and aluminum materials, the aluminum winding transformer itself has insufficient performance. At the same time, there are a huge number of transformer manufacturing enterprises, and many small enterprises that do not have the necessary capabilities such as quality control and testing and testing are among them. It is even more difficult to guarantee the quality of the aluminum winding transformers they produce. According to the statistical analysis of transformer equipment accidents of the State Grid Corporation of China, it shows that transformer windings are the main damage parts of transformer damage accidents, exceeding 70% of the total damage accidents. Among them, insufficient short-circuit resistance of windings and defective insulation are the main reasons for damage accidents. It can be seen from the accident analysis that the quality problems of transformer windings can easily cause safety accidents, and the use of existing aluminum winding transformers will greatly increase the risk of transformer damage and bury safety hazards in the operation of the entire power system. Therefore, the quality control of transformer windings must be strengthened to identify substandard aluminum winding transformers in power systems.
我国电力变压器出厂必须经过例行试验、型式试验和特殊试验，其中与变压器绕组密切相关的试验包括：绕组电阻测量、短路试验、空载试验、温升试验等。这些试验都不能用于检测铝绕组变压器，国内外也没有相关的研究。目前，电力运检部门只能通过吊罩后破坏绕组绝缘才能检测出绕组导体类型。但是，该方法费时费力、准确度不高同时具有不可逆性。my country's power transformers must go through routine tests, type tests and special tests before leaving the factory. The tests closely related to transformer windings include: winding resistance measurement, short circuit test, no-load test, temperature rise test, etc. None of these tests can be used to detect aluminum winding transformers, and there is no relevant research at home and abroad. At present, the power inspection department can only detect the type of winding conductor by destroying the winding insulation behind the hood. However, this method is time-consuming, has low accuracy and is irreversible.
目前，国内外均没有有效的可用于鉴别变压器绕组材质的检测方法。只能通过吊罩后破坏绕组绝缘才能检测出绕组导体类型。At present, there is no effective detection method that can be used to identify the material of transformer windings at home and abroad. The winding conductor type can only be detected by breaking the winding insulation after passing through the hood.
发明内容Contents of the invention
鉴于此，本发明的目的是提供一种基于声的变压器绕组材质鉴别方法。In view of this, the object of the present invention is to provide a method for identifying the material of transformer windings based on sound.
本发明的目的是通过以下技术方案实现的，一种基于声速的变压器绕组材质鉴别方法，根据声波在变压器绕组中传播的速度，判断绕组的材质。The object of the present invention is achieved through the following technical solutions, a method for identifying the material of a transformer winding based on the speed of sound, which judges the material of the winding according to the speed at which sound waves propagate in the transformer winding.
优选的，该方法具体包括以下步骤：Preferably, the method specifically includes the following steps:
S1.利用激振器在变压器绕组首端产生可听声波；S1. Use the exciter to generate audible sound waves at the head end of the transformer winding;
S2.安装在变压器绕组首末两端的声音传感器分别接收声波信号；S2. The sound sensors installed at the first and last ends of the transformer winding respectively receive the sound wave signals;
S3.声音传感器采集到的信号接入示波器，两波形首波时间差即为声波传播时间；利用公式v＝L/t计算声波传播速度，其中，v为声速；L为声波传播距离；t为声波传播时间；S3. The signal collected by the sound sensor is connected to the oscilloscope, and the time difference between the first waves of the two waveforms is the sound wave propagation time; the sound wave propagation speed is calculated using the formula v=L/t, wherein, v is the sound speed; L is the sound wave propagation distance; t is the sound wave propagation time;
S4.将计算获得的声波传播速度与已知声波传播速度鉴别变压器绕组的材质。S4. Discriminate the material of the transformer winding from the calculated sound wave propagation speed and the known sound wave propagation speed.
优选的，所述可听声波的频率为20Hz～20000。Preferably, the frequency of the audible sound wave is 20Hz-20000Hz.
由于采用了上述技术方案，本发明具有如下的优点：Owing to adopting above-mentioned technical scheme, the present invention has following advantage:
本发明在不破坏绕组绝缘的情况下，可以简单快捷地进行变压器绕组材质是否为铜材质的鉴别。The invention can simply and quickly identify whether the material of the transformer winding is copper without damaging the insulation of the winding.
附图说明Description of drawings
为了使本发明的目的、技术方案和优点更加清楚，下面将结合附图对本发明作进一步的详细描述，其中：In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail below in conjunction with the accompanying drawings, wherein:
图1为变压器绕组材质鉴别方法流程图；Fig. 1 is a flow chart of the identification method of transformer winding material;
图2为变压器绕组回路声速试验原理图；Figure 2 is a schematic diagram of the sound velocity test of the transformer winding circuit;
图3为典型波形图。Figure 3 is a typical waveform diagram.
具体实施方式Detailed ways
以下将结合附图，对本发明的优选实施例进行详细的描述；应当理解，优选实施例仅为了说明本发明，而不是为了限制本发明的保护范围。The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings; it should be understood that the preferred embodiments are only for illustrating the present invention, rather than limiting the protection scope of the present invention.
声波是在弹性介质(固体、液体、气体)中传播的一种机械振动。声波的传播速度几乎与频率无关，主要由介质的密度、杨氏模量和泊松比等弹性参数决定。本发明中传播介质为固体，声速主要由材质特性决定。Sound waves are mechanical vibrations that propagate in elastic media (solids, liquids, gases). The propagation speed of sound waves has almost nothing to do with frequency, and is mainly determined by elastic parameters such as the density of the medium, Young's modulus and Poisson's ratio. In the present invention, the propagation medium is solid, and the sound velocity is mainly determined by the material properties.
目前变压器绕组材质主要为铜材和铝材两种。室温下，声音在铜中的传播速度为3810m·s-1，在铝中的传播速度为5000m·s-1，差异为31.2％。因此，利用声速的差异可以有效的判断变压器绕组材质是铜材还是铝材。At present, the transformer winding materials are mainly copper and aluminum. At room temperature, the propagation velocity of sound in copper is 3810m·s -1 , and that in aluminum is 5000m·s -1 , the difference is 31.2%. Therefore, the difference in sound velocity can be used to effectively determine whether the transformer winding material is copper or aluminum.
根据前述，本发明提供一种基于声速的变压器绕组材质鉴别方法，所述方法是利用声波在不同材质变压器绕组中的传播速度差异进行材质鉴别。其具体步骤为：According to the foregoing, the present invention provides a method for identifying materials of transformer windings based on sound velocity, which uses the difference in propagation speed of sound waves in transformer windings of different materials to identify materials. The specific steps are:
S1.利用激振器在变压器绕组首端产生可听声波；S1. Use the exciter to generate audible sound waves at the head end of the transformer winding;
S2.安装在变压器绕组首末两端的声音传感器分别接收声波信号；S2. The sound sensors installed at the first and last ends of the transformer winding respectively receive the sound wave signals;
S3.声音传感器采集到的信号接入示波器，两波形首波时间差即为声波传播时间；利用公式v＝L/t计算声波传播速度，其中，v为声速；L为声波传播距离；t为声波传播时间；S3. The signal collected by the sound sensor is connected to the oscilloscope, and the time difference between the first waves of the two waveforms is the sound wave propagation time; the sound wave propagation speed is calculated using the formula v=L/t, wherein, v is the sound speed; L is the sound wave propagation distance; t is the sound wave propagation time;
S4.将计算获得的声波传播速度与已知声波传播速度鉴别变压器绕组的材质。S4. Discriminate the material of the transformer winding from the calculated sound wave propagation speed and the known sound wave propagation speed.
声速的种类主要由频率不同来划分。频率在20～20000Hz的声波称为可听声波；频率高于20000Hz声波称为超声波；频率低于20Hz的机械波称为次声波。介质对声波的吸收与声波频率有关，对于同一物质，声波的频率越高，吸收越强，声波衰减也就越快。因此本发明中不适合使用超声波，采用频率较低的20～20000Hz的可听声波。The types of sound speed are mainly divided by frequency. Sound waves with a frequency between 20 and 20,000 Hz are called audible sound waves; sound waves with a frequency higher than 20,000 Hz are called ultrasonic waves; mechanical waves with a frequency lower than 20 Hz are called infrasonic waves. The absorption of sound waves by the medium is related to the frequency of the sound waves. For the same substance, the higher the frequency of the sound waves, the stronger the absorption and the faster the attenuation of the sound waves. Therefore, ultrasonic waves are not suitable for use in the present invention, and audible sound waves with a lower frequency of 20-20000 Hz are used.
声波激励由标准的激振器产生，使用时激振器安装在变压器绕组首端。The sound wave excitation is generated by a standard exciter, which is installed at the head end of the transformer winding when in use.
声波接收采用接触式声音传感器：试验选用的传感器为CM-01接触式传感器。CM-01B接触式传声器是由灵敏度好，性能稳定的压电薄膜结合一个低噪音的前置放大器电路组成，能以缓冲输出的方式提供唯一的声音和振动信号的拾取。在产品的结构设计时，尽量将外部的噪音干扰降到最低，从而当产品中间的橡胶垫接收到振动信号的时候，能输出一个高灵敏度的信号。下表为传感器性能参数：Sound wave reception adopts contact sound sensor: the sensor selected for the test is CM-01 contact sensor. The CM-01B contact microphone is composed of a piezoelectric film with good sensitivity and stable performance combined with a low-noise preamplifier circuit, which can provide only sound and vibration signal pickup in the form of buffered output. In the structural design of the product, try to minimize the external noise interference, so that when the rubber pad in the middle of the product receives a vibration signal, it can output a high-sensitivity signal. The following table shows the sensor performance parameters:
表1传感器性能参数Table 1 Sensor Performance Parameters
已知变压器绕组材质主要为铜材和铝材两种。室温下，声音在铜中的传播速度为3810m·s-1，在铝中的传播速度为5000m·s-1，差异为31.2％。It is known that the materials of transformer windings are mainly copper and aluminum. At room temperature, the propagation velocity of sound in copper is 3810m·s -1 , and that in aluminum is 5000m·s -1 , the difference is 31.2%.
将试验测得的声速v与已知铜材的声速进行比较，考虑一定的裕度，取(3500，4100)m·s-1区间作为变压器绕组材质为铜材的判据。试验测得的声速v在(3500，4100)m·s-1区间范围内时判断变压器绕组材质为铜材，否则变压器绕组材质为非纯铜材。Comparing the sound velocity v measured by the test with the sound velocity of known copper materials, and considering a certain margin, the (3500, 4100) m·s -1 interval is taken as the criterion for the transformer winding material to be copper. When the sound velocity v measured by the test is in the range of (3500, 4100) m·s -1 , it is judged that the material of the transformer winding is copper, otherwise the material of the transformer winding is not pure copper.
以上所述仅为本发明的优选实施例，并不用于限制本发明，显然，本领域的技术人员可以对本发明进行各种改动和变型而不脱离本发明的精神和范围。这样，倘若本发明的这些修改和变型属于本发明权利要求及其等同技术的范围之内，则本发明也意图包含这些改动和变型在内。The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.
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| 金属材料声参量的初步研究及应用;田彦平;《中国优秀硕士学位论文全文数据库 工程科技Ⅰ辑》;20150215(第2期);第8页第1-3段，第12页第3.2.2节，第31页倒数第2段 * |
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| CN105158341A (en) | 2015-12-16 |
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