CN102830375A - Device and method for measuring temperature properties of permanent magnet and permanent magnet material in open circuit - Google Patents
Device and method for measuring temperature properties of permanent magnet and permanent magnet material in open circuit Download PDFInfo
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Abstract
Description
技术领域 technical field
本发明涉及永磁材料特性测量技术领域,尤其涉及一种在开路中测量永磁体和永磁材料温度特性的装置及方法。 The invention relates to the technical field of measuring the characteristics of permanent magnet materials, in particular to a device and method for measuring the temperature characteristics of permanent magnets and permanent magnet materials in an open circuit. the
背景技术 Background technique
温度特性是永磁材料的重要特性参数,包括可逆温度系数和不可损失,在永磁材料的应用中尤为关注,因此温度特性的测量变得更为重要。目前,永磁材料的温度特性测量方法有三类:⑴第一类,如国家标准GB/T24270-2009“永磁材料磁性能温度系数测量方法”所要求的方法:在闭合磁路下测量不同温度下永磁材料的磁滞回线或退磁曲线,由此得到不同温度下的永磁材料的特性参数顽磁Br、磁通密度矫顽力HcB以及磁极化强度矫顽力HcJ和BH能积的最大值(BH)max,然后计算对应参数的温度系数。实现该方法的现有装置的不足之处是只能测量室温以上的情况,而且实现负温或250℃以上温度较为困难;控温精度和测量精度较低。⑵第二类,在开磁路下用振动样品磁强计测量不同温度下测试样品的磁矩;或用磁强计测量不同温度下测试样品的磁通密度;或利用电磁感应原理采用探测线圈测量样品的磁通,然后计算温度特性。第一种振动或提拉样品磁强计测量磁矩法是现有技术常用的测量方法,该方法的缺点是要求测试样品的尺寸小,样品定位困难,测量重复性较差,且设备复杂昂贵。CN2114169U是改进型的提拉样品磁强计,该方法增加了一个无场探测线圈测量开路磁通。第二种在开磁路下用磁强计(特斯拉计)测量磁通密度法。CN1036835A测量的是磁路中的气隙磁通密度,而不是永磁材料本身的参数,且控温精度低;CN2352958Y的缺点是测量霍尔探头离样品距离远,感应信号较弱,即使采用了磁屏蔽特殊装置也难解决信号较弱、灵敏度不足的问题;CN1797023A的缺点是测量霍尔探头本身的控温困难,测量重复性差,样品形状限定为环形,且尺寸较大。第三种采用探测线圈测量温度特性有许多不足,CN2352958Y专利对第三种方法的不足之处进行了说明;CN2384229Y对此方法进行了改进,并实现了多样品测量,不足之处是所样品之间互相干扰;CN101587175也是对第三种的改进,克服了已有方法的许多不足,但探测线圈的耐温问题受限制。⑶第三类,在开磁路下采用核磁共振法测量磁感强度。CN101109720B就是采用该方法;CN101109720B要求提供核磁共振所需的磁场非常均匀,且不能受环境温度的影响,因此实现较为困难。在磁测量方法中,核磁共振磁强计的准确度最高,电磁感应法磁通计其次,霍尔效应法的磁强计第三。上述三类测量温度特性方法中,第一类早期测量磁场强度H采用霍尔效应法的霍尔探 头,测量磁通密度B或磁极化强度J采用电磁感应法的线圈,目前主流采用电磁感应法的双线圈测量磁场强度H和磁通密度B或磁极化强度J;第二类也分别采用了电磁感应法和霍尔效应法;第三类采用的是核磁共振法。它们各有优缺点,其测量装置存在各种不足。在永磁材料温度特性的测量实践中,尤其测量温度系数较小(温度系数小于0.01%/℃)的永磁材料,现有方法存在分辨率不足、重复性差的问题,需要一种更好的测量方法。 Temperature characteristics are important characteristic parameters of permanent magnet materials, including reversible temperature coefficient and non-loss, which are especially concerned in the application of permanent magnet materials, so the measurement of temperature characteristics becomes more important. At present, there are three types of measurement methods for the temperature characteristics of permanent magnet materials: (1) The first type, such as the method required by the national standard GB/T24270-2009 "Measurement Method for Temperature Coefficient of Magnetic Properties of Permanent Magnetic Materials": measure different temperatures under a closed magnetic circuit The hysteresis loop or demagnetization curve of the permanent magnet material can be used to obtain the characteristic parameters of the permanent magnet material at different temperatures: coercive force B r , magnetic flux density coercive force H cB and magnetic polarization coercive force H cJ and BH The maximum value of the energy product (BH) max , and then calculate the temperature coefficient of the corresponding parameter. The disadvantage of the existing device for realizing this method is that it can only measure the situation above room temperature, and it is difficult to realize negative temperature or temperature above 250°C; the temperature control accuracy and measurement accuracy are low. (2) The second category, use a vibrating sample magnetometer to measure the magnetic moment of the test sample at different temperatures under the open magnetic circuit; or use a magnetometer to measure the magnetic flux density of the test sample at different temperatures; or use the principle of electromagnetic induction to use the detection coil The magnetic flux of the sample is measured, and then the temperature characteristic is calculated. The first method of vibrating or pulling the sample magnetometer to measure the magnetic moment is a commonly used measurement method in the prior art. The disadvantages of this method are that the size of the test sample is small, the sample positioning is difficult, the measurement repeatability is poor, and the equipment is complicated and expensive. . CN2114169U is an improved pull sample magnetometer, the method adds a field-free detection coil to measure open-circuit magnetic flux. The second method uses a magnetometer (Tesla meter) to measure the magnetic flux density under an open magnetic circuit. CN1036835A measures the air gap magnetic flux density in the magnetic circuit, rather than the parameters of the permanent magnet material itself, and the temperature control accuracy is low; the disadvantage of CN2352958Y is that the distance between the Hall probe and the sample is far, and the induction signal is weak. The special magnetic shielding device is also difficult to solve the problems of weak signal and insufficient sensitivity; the disadvantage of CN1797023A is that it is difficult to measure the temperature control of the Hall probe itself, the measurement repeatability is poor, the shape of the sample is limited to a ring, and the size is large. The third method adopts detection coils to measure temperature characteristics and has many shortcomings, and the CN2352958Y patent has explained the shortcomings of the third method; CN2384229Y has improved this method and realized multi-sample measurement. Interference between each other; CN101587175 is also an improvement to the third type, which overcomes many shortcomings of the existing methods, but the temperature resistance of the detection coil is limited. (3) The third category, the magnetic induction intensity is measured by nuclear magnetic resonance method under the open magnetic circuit. CN101109720B adopts this method exactly; CN101109720B requires that the magnetic field required for nuclear magnetic resonance is very uniform and cannot be affected by ambient temperature, so it is difficult to realize. Among the magnetic measurement methods, the accuracy of the NMR magnetometer is the highest, followed by the fluxmeter of the electromagnetic induction method, and the third of the magnetometer of the Hall effect method. Among the above three methods of measuring temperature characteristics, the first type uses Hall effect probes to measure magnetic field strength H in the early stage, and coils to measure magnetic flux density B or magnetic polarization J using electromagnetic induction methods. At present, the mainstream uses electromagnetic induction methods. The double coil measures the magnetic field strength H and the magnetic flux density B or the magnetic polarization J; the second type also uses the electromagnetic induction method and the Hall effect method respectively; the third type uses the nuclear magnetic resonance method. They have their own advantages and disadvantages, and there are various deficiencies in their measuring devices. In the practice of measuring the temperature characteristics of permanent magnet materials, especially permanent magnet materials with small temperature coefficients (temperature coefficients less than 0.01%/°C), the existing methods have problems of insufficient resolution and poor repeatability, and a better method is needed Measurement methods.
发明内容 Contents of the invention
为了克服现有的永磁材料温度特性测量方法的不足,本发明提出了一种在开路中测量永磁体和永磁材料温度特性的装置及方法,解决现有技术中存在分辨率不足、重复性差的问题。 In order to overcome the shortcomings of the existing methods for measuring the temperature characteristics of permanent magnet materials, the present invention proposes a device and method for measuring the temperature characteristics of permanent magnets and permanent magnet materials in an open circuit, which solves the problems of insufficient resolution and poor repeatability in the prior art The problem. the
本发明提供了一种在开路中测量永磁体和永磁材料温度特性的装置,包括样品盒、温度检测与处理单元、感应电压产生单元、感应电压检测和处理单元、样品提拉控制单元、温度实现单元、计算机控制和处理单元。所述的样品盒用于放置待测样品,并对待测样品保温;所述样品盒为底部是平面的柱体。 The invention provides a device for measuring the temperature characteristics of permanent magnets and permanent magnet materials in an open circuit, including a sample box, a temperature detection and processing unit, an induced voltage generation unit, an induced voltage detection and processing unit, a sample pulling control unit, a temperature Implementation unit, computer control and processing unit. The sample box is used to place the sample to be tested and keep it warm; the sample box is a cylinder with a flat bottom. the
作为本发明的进一步改进:所述的样品盒包括:样品盒体,由非导磁材料而成;样品盒上盖,由非导磁材料而成,中部有通孔;样品盒保温层;以及样品盒内腔,用于放置待测样品。 As a further improvement of the present invention: the sample box includes: the sample box body, made of non-magnetic material; the upper cover of the sample box, made of non-magnetic material, with a through hole in the middle; the sample box insulation layer; and The inner cavity of the sample box is used to place the sample to be tested. the
作为本发明的进一步改进:所述的温度检测与处理单元用于检测待测样品的温度,并对温度进行显示、处理,所述温度检测与处理单元包括:温度传感器和温度测量仪;所述温度传感器用于测量温度信号,并安装在所述的样品盒上盖的通孔中,与待测样品接触;所述温度测量仪用于接受温度传感器的信号,实时显示温度值,并将温度信号传送到所述的计算机控制和处理单元。 As a further improvement of the present invention: the temperature detection and processing unit is used to detect the temperature of the sample to be tested, and display and process the temperature, the temperature detection and processing unit includes: a temperature sensor and a temperature measuring instrument; The temperature sensor is used to measure the temperature signal, and is installed in the through hole of the upper cover of the sample box, and is in contact with the sample to be tested; the temperature measuring instrument is used to receive the signal of the temperature sensor, display the temperature value in real time, and record the temperature The signal is sent to the computer control and processing unit. the
作为本发明的进一步改进:所述的感应电压产生单元用于获取待测样品产生的感应电压信号,所述感应电压产生单元包括:亥姆霍兹线圈,用于感应由待测样品产生的感应电压信号;以及亥姆霍兹线圈的基座,基座端面的上下面互相平行以保证亥姆霍兹线圈的轴线与基座端面的平面垂直,基座上有一个定位槽。 As a further improvement of the present invention: the induced voltage generation unit is used to obtain the induced voltage signal generated by the sample to be tested, and the induced voltage generation unit includes: a Helmholtz coil, used to induce the induced voltage signal generated by the sample to be tested voltage signal; and the base of the Helmholtz coil, the upper and lower sides of the end face of the base are parallel to each other to ensure that the axis of the Helmholtz coil is perpendicular to the plane of the end face of the base, and there is a positioning groove on the base. the
作为本发明的进一步改进:所述的感应电压检测和处理单元,用于检测和处理感应电压信号,将感应电压信号转换成磁通数据,所述感应电压检测和处理单元包括:数字电压积分器,其输入端与所述亥姆霍兹线圈的输出端连接,用于接收该亥姆霍兹线圈的感应电压与时间信号;以及信号放大器,其输入端与上述数字电压积分器的输出端连接,将信号放大后由其输出端与所述的计算机控制和处理单元连接。 As a further improvement of the present invention: the induced voltage detection and processing unit is used to detect and process the induced voltage signal, and convert the induced voltage signal into magnetic flux data, and the induced voltage detection and processing unit includes: a digital voltage integrator , whose input end is connected to the output end of the Helmholtz coil, for receiving the induced voltage and time signal of the Helmholtz coil; and a signal amplifier, whose input end is connected to the output end of the above-mentioned digital voltage integrator After the signal is amplified, its output terminal is connected with the computer control and processing unit. the
作为本发明的进一步改进:所述的感应电压检测和处理单元,用于检测和处理感应电压信号,将感应电压信号转换成磁通数据;所述感应电压检测和处理单元是数字磁通计,数字磁通计输入端与上述亥姆霍兹线圈的输出端连接,其输出端与所述的计算机控制和处理单元连接。 As a further improvement of the present invention: the induced voltage detection and processing unit is used to detect and process the induced voltage signal, and convert the induced voltage signal into magnetic flux data; the induced voltage detection and processing unit is a digital fluxmeter, The input end of the digital fluxmeter is connected with the output end of the Helmholtz coil, and the output end is connected with the computer control and processing unit. the
作为本发明的进一步改进:所述的样品提拉控制单元,用于控制和提拉样品盒,将样品盒提拉到规定的位置,所述的样品提拉控制单元包括:样品夹具,用于放置样品盒,并被样品提拉控制单元提拉;样品夹具滑轨,通过样品夹具的三个通孔与样品夹具相连接,用于保证样品夹具沿与亥姆霍兹线圈轴线平行的轴线移动;电机,用于驱动样品夹具沿与亥姆霍兹线圈轴线平行的轴线移动;以及样品夹具限位装置,用于限定样品夹具的位置;样品夹具和样品夹具滑轨为非导磁材料而成。 As a further improvement of the present invention: the sample lifting control unit is used to control and pull the sample box, and pull the sample box to a specified position, and the sample lifting control unit includes: a sample clamp for The sample box is placed and pulled by the sample lifting control unit; the sample holder slide rail is connected with the sample holder through the three through holes of the sample holder to ensure that the sample holder moves along the axis parallel to the Helmholtz coil axis ; The motor is used to drive the sample holder to move along the axis parallel to the Helmholtz coil axis; and the sample holder limit device is used to limit the position of the sample holder; the sample holder and the sample holder sliding rail are made of non-magnetic materials . the
作为本发明的进一步改进:所述的温度实现单元,使待测样品的温度控制到预定的温度,并保持温度稳定;其包括:工作室,用于放置含有待测样品和安装温度传感器的样品盒;加热装置,用于将所述工作室加热升温,该加热装置受控于所述的计算机控制和处理单元;冷却装置,用于将所述工作室冷却降温,该冷却装置受控于所述的计算机控制和处理单元;以及温度检测与显示装置,用于检测上述工作室的温度,并实时显示温度值。 As a further improvement of the present invention: the temperature realization unit controls the temperature of the sample to be tested to a predetermined temperature and keeps the temperature stable; it includes: a working room for placing the sample containing the sample to be tested and installing a temperature sensor box; a heating device, used to heat up the working chamber, the heating device is controlled by the computer control and processing unit; a cooling device, used to cool down the working chamber, the cooling device is controlled by the The above-mentioned computer control and processing unit; and a temperature detection and display device for detecting the temperature of the above-mentioned working room and displaying the temperature value in real time. the
作为本发明的进一步改进:所述的温度实现单元,使待测样品的温度控制到预定的温度,并保持温度稳定;其是带温度检测与显示装置的高低温度试验箱。 As a further improvement of the present invention: the temperature realization unit controls the temperature of the sample to be tested to a predetermined temperature and keeps the temperature stable; it is a high and low temperature test chamber with a temperature detection and display device. the
作为本发明的进一步改进:所述的感应电压产生单元、样品提拉控制单元与温度实现单元是分离的,感应电压产生单元和样品提拉控制单元没有放置于温度实现单元中。 As a further improvement of the present invention: the induced voltage generating unit, the sample pulling control unit and the temperature realization unit are separated, and the induced voltage generation unit and the sample pulling control unit are not placed in the temperature realization unit. the
作为本发明的进一步改进:所述的待测样品为具有单一磁化方向的永磁体。 As a further improvement of the present invention: the sample to be tested is a permanent magnet with a single magnetization direction. the
本发明同时提供了一种在开路中测量永磁体和永磁材料温度特性的装置的方法,根据电磁感应原理,采用提拉法利用样品提拉控制单元使待测样品在感应电压产生单元的亥姆霍兹线圈中产生感应电动势,由感应电压检测和处理单元的数字电压积分器或磁通计检测并获取感应电动势的,经信号放大后,将信号转送到计算机控制和处理单元,计算机控制和处理单元获取不同温度下参数的温度系数;所述参数包括待测样品的磁矩m、工作点的磁化强度Md、工作点的磁通密度Bd,以及所用永磁材料的顽磁Br、磁通密度矫顽力HcB以及BH能积的最大值(BH)max,所述温度特性包括在测量温度范围的平均温度系数、不可逆损失以及任意点的温度系数。 The present invention also provides a method for measuring the temperature characteristics of permanent magnets and permanent magnet materials in an open circuit. According to the principle of electromagnetic induction, the pulling method is used to use the sample pulling control unit to make the sample to be tested in the position of the induced voltage generating unit. The induced electromotive force generated in the Holtz coil is detected and obtained by the digital voltage integrator or fluxmeter of the induced voltage detection and processing unit. After the signal is amplified, the signal is transferred to the computer control and processing unit, and the computer control and The processing unit obtains the temperature coefficient of the parameters at different temperatures; the parameters include the magnetic moment m of the sample to be tested, the magnetization M d of the working point, the magnetic flux density B d of the working point, and the coercive B r of the permanent magnetic material used , the magnetic flux density coercive force H cB and the maximum value of the BH energy product (BH) max , the temperature characteristics include the average temperature coefficient in the measurement temperature range, the irreversible loss and the temperature coefficient at any point.
本发明的有益效果是:待测样品形状没有限制,只要求为单一磁化方向,适用范围宽;能够实现自动测量,测量重复性好;该方法的测量准确度高,特别适合于测量温度系数 较小(如温度系数小于0.01%/℃)的永磁材料。 The beneficial effects of the invention are: the shape of the sample to be tested is not limited, only a single magnetization direction is required, and the application range is wide; automatic measurement can be realized, and the measurement repeatability is good; the measurement accuracy of the method is high, and it is especially suitable for measuring temperature coefficients. Small (such as temperature coefficient less than 0.01%/℃) permanent magnet materials. the
【附图说明】 【Description of drawings】
图1为本发明实施例1的装置示意图;
Fig. 1 is the device schematic diagram of
图2为本发明感应电压产生单元示意图; 2 is a schematic diagram of an induced voltage generating unit of the present invention;
图3为本发明样品盒示意图; Fig. 3 is a schematic diagram of a sample box of the present invention;
图4为本发明样品提拉控制单元示意图; Fig. 4 is a schematic diagram of the sample pulling control unit of the present invention;
图5为本发明样品提拉控制单元的样品夹具底部俯视图; Fig. 5 is a bottom plan view of the sample holder of the sample pulling control unit of the present invention;
图6为本发明实施例2的装置示意图;
Fig. 6 is the schematic diagram of the device of
图7为本发明实施例3的装置示意图。
Fig. 7 is a schematic diagram of the device of
【具体实施方式】 【Detailed ways】
下面结合附图说明及具体实施方式对本发明进一步说明。 The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.
本发明提供了一种在开路中测量永磁体和永磁材料温度特性的装置,包括样品盒2、温度检测与处理单元3、感应电压产生单元4、感应电压检测和处理单元5、样品提拉控制单元6、温度实现单元7、计算机控制和处理单元8。所述的样品盒2用于放置待测样品1,并对待测样品1保温;所述样品盒2为底部是平面的柱体,为任意形状的柱体,优选设计之一是圆柱体。
The invention provides a device for measuring the temperature characteristics of permanent magnets and permanent magnet materials in an open circuit, including a
所述的样品盒2包括:样品盒体21,由非导磁材料而成,优选方案之一为聚四氟乙烯;样品盒上盖22,由非导磁材料而成,中部有通孔;样品盒保温层23;以及样品盒内腔24,用于放置待测样品1。一实施例中,样品盒上盖22,采用样品盒体21相同的方案,中部有可以安装温度传感器31的通孔;样品盒保温层23;填充保温材料,优选方案之一为石棉;以及样品盒内腔24,用于放置待测样品1,内腔形状根据待测样品1的形状设计,优选方案之一为圆柱形。
The
所述的温度检测与处理单元3用于检测待测样品1的温度,并对温度进行显示、处理,所述温度检测与处理单元3包括:温度传感器31和温度测量仪32;所述温度传感器31用于测量温度信号,并安装在所述的样品盒上盖22的通孔中,与待测样品1接触;所述温度测量仪32用于接受温度传感器31的信号,实时显示温度值,并将温度信号传送到所述的计算机控制和处理单元8。
The temperature detection and
温度传感器31优选方案之一为铂电阻,可以用于-60℃到260℃的温度测量;优选方案之二为热电偶,可以用于-210℃到1300℃的温度测量。
One of the preferred solutions of the
所述的感应电压产生单元4用于获取待测样品1产生的感应电压信号,所述感应电 压产生单元4包括:亥姆霍兹线圈41,用于感应由待测样品1产生的感应电压信号;以及亥姆霍兹线圈41的基座42,基座42端面的上下面互相平行以保证亥姆霍兹线圈41的轴线与基座42端面的平面垂直,基座42上有一个定位槽。
The induced voltage generating unit 4 is used to obtain the induced voltage signal generated by the sample to be tested 1, and the induced voltage generating unit 4 includes: a
所述的感应电压检测和处理单元5,用于检测和处理感应电压信号,将感应电压信号转换成磁通数据,所述感应电压检测和处理单元5包括:数字电压积分器51,其输入端与所述亥姆霍兹线圈41的输出端连接,用于接收该亥姆霍兹线圈41的感应电压与时间信号;以及信号放大器52,其输入端与上述数字电压积分器51的输出端连接,将信号放大后由其输出端与所述的计算机控制和处理单元8连接。
The induced voltage detection and processing unit 5 is used to detect and process the induced voltage signal, and convert the induced voltage signal into magnetic flux data. The induced voltage detection and processing unit 5 includes: a
所述的感应电压检测和处理单元5,用于检测和处理感应电压信号,将感应电压信号转换成磁通数据;所述感应电压检测和处理单元5是数字磁通计,数字磁通计输入端与上述亥姆霍兹线圈41的输出端连接,其输出端与所述的计算机控制和处理单元8连接。
The induced voltage detection and processing unit 5 is used to detect and process the induced voltage signal, and convert the induced voltage signal into magnetic flux data; the induced voltage detection and processing unit 5 is a digital fluxmeter, and the digital fluxmeter input The terminal is connected with the output terminal of the above-mentioned
所述的样品提拉控制单元6,用于控制和提拉样品盒,将样品盒提拉到规定的位置,所述的样品提拉控制单元6包括:样品夹具61,用于放置样品盒2,并被样品提拉控制单元6提拉;样品夹具滑轨62,通过样品夹具61的三个通孔611与样品夹具61相连接,用于保证样品夹具61沿与亥姆霍兹线圈41轴线平行的轴线移动;电机63,用于驱动样品夹具61沿与亥姆霍兹线圈41轴线平行的轴线移动;以及样品夹具限位装置64,用于限定样品夹具61的位置;样品夹具61和样品夹具滑轨62为非导磁材料而成。
The sample
所述的温度实现单元7,使待测样品1的温度控制到预定的温度,并保持温度稳定;其包括:工作室71,用于放置含有待测样品1和安装温度传感器31的样品盒2;加热装置72,用于将所述工作室71加热升温,该加热装置72受控于所述的计算机控制和处理单元8;冷却装置73,用于将所述工作室71冷却降温,该冷却装置73受控于所述的计算机控制和处理单元8;以及温度检测与显示装置74,用于检测上述工作室71的温度,并实时显示温度值。
The
所述的温度实现单元7,使待测样品1的温度控制到预定的温度,并保持温度稳定;其是带温度检测与显示装置74的高低温度试验箱。
The
所述的感应电压产生单元4、样品提拉控制单元6与温度实现单元7是分离的,感应电压产生单元4和样品提拉控制单元6没有放置于温度实现单元7中,从而消除了温度对感应电压产生单元4的不利影响。
The induced voltage generation unit 4, the sample pulling
所述的待测样品1为具有单一磁化方向的永磁体。 The sample to be tested 1 is a permanent magnet with a single magnetization direction. the
本发明同时提供了一种在开路中测量永磁体和永磁材料温度特性的装置的方法,根 据电磁感应原理,采用提拉法利用样品提拉控制单元6使待测样品1在感应电压产生单元4的亥姆霍兹线圈41中产生感应电动势,由感应电压检测和处理单元5的数字电压积分器51或磁通计检测并获取感应电动势的,经信号放大后,将信号转送到计算机控制和处理单元8,计算机控制和处理单元8获取不同温度下参数的温度系数;所述参数包括待测样品1的磁矩m、工作点的磁化强度Md、工作点的磁通密度Bd,以及所用永磁材料的顽磁Br、磁通密度矫顽力HcB以及BH能积的最大值(BH)max,所述温度特性包括在测量温度范围的平均温度系数、不可逆损失以及任意点的温度系数。
The present invention also provides a method for measuring the temperature characteristics of permanent magnets and permanent magnet materials in an open circuit. According to the principle of electromagnetic induction, the sample pulling
以下通过几个实施例来进一步说明。 Further description will be given below through several examples. the
实施例1:参考图1所示,本实施例为一个自动化实施例,用于在开磁路中永磁体和永磁材料温度特性的测量。 Embodiment 1: As shown in FIG. 1 , this embodiment is an automatic embodiment for measuring the temperature characteristics of permanent magnets and permanent magnetic materials in an open magnetic circuit. the
本实施例由样品盒2、温度检测与处理单元3、感应电压产生单元4、感应电压检测和处理单元5、样品提拉控制单元6、温度实现单元7、计算机实现和处理单元8组成。
This embodiment consists of a
样品盒2用于放置待测样品1和对待测样品1保温,如图3所示,样品盒2由盒体21、上盖22、保温层23和内腔24组成,待测样品1放置在内腔中。
The
温度检测与处理单元3用于测量待测样品1温度,并将温度信号输送到计算机控制和处理单元8,由温度传感器31和温度测量仪32组成。温度传感器31为铂电阻或热电偶,与温度测量仪32连接。
The temperature detection and
感应电压产生单元4用于感应由待测样品1产生的感应电压信号,如图2所示,由亥姆霍兹线圈41和带有一个定位槽、用于样品夹具61的定位的基座42组成。提拉控制单元6将样品盒2从亥姆霍兹线圈41中提拉出去,使亥姆霍兹线圈41产生感应电压信号。
The induced voltage generating unit 4 is used for inducing the induced voltage signal generated by the sample to be tested 1, as shown in FIG. composition. The pulling
感应电压检测和处理单元5,用于亥姆霍兹线圈41感应的电压与时间信号采集、放大并输送,由数字电压积分器51和信号放大器52组成,数字电压积分器51的输入端与亥姆霍兹线圈41的输出端连接,用于采集亥姆霍兹线圈41感应的电压与时间信号,输出端与信号放大器52的输入端连接,信号放大器52的输出端与计算机实现和处理单元8连接。
The induced voltage detection and processing unit 5 is used for collecting, amplifying and transmitting the voltage and time signals induced by the
样品提拉控制单元6用于将样品盒2从亥姆霍兹线圈41中提拉出去,如图4、图5所示,由样品夹具61、滑轨62、电机63和样品夹具限位装置64组成;样品提拉控制单元6的输出端与计算机实现和处理单元8连接,并由计算机实现和处理单元8控制提拉位置。
The sample pulling
温度实现单元7由工作室71、加热装置72、冷却装置73和温度检测与显示装置74组成,并与计算机实现和处理单元8连接和控制。
The
加热装置72,用于将放置在工作室71中的样品盒2内腔24中的待测样品1加热升 温,具体可由电阻丝、鼓风机等组成,电阻丝主要用来加热提高工作室71中的样品盒2内腔24中的待测样品1的温度;当待测样品1的温度大于预先要求温度时,依靠鼓风机对工作室71的鼓风冷却来散热,直到到达预先要求温度。
The
冷却装置73,用于将放置在工作室71中的样品盒2内腔24中待测样品1冷却降温,具体可由压缩机和制冷剂组成,或者采用液氮装置;当待测样品1的温度低于预先要求温度时,依靠加热装置72对工作室71的加热来提高温度,直到到达预先要求温度。
The
计算机控制和处理单元8向温度实现单元7发出温度控制指令,控制加热装置72、冷却装置73进行工作;记录并存储温度检测与处理单元3输送的温度信号;接收感应电压检测和处理单元5输送的信号,并转换成相应磁通值。
The computer control and processing unit 8 sends temperature control instructions to the
实施例2,参考图6所示,本实施例中感应电压检测和处理单元5是数字磁通计,数字磁通计输入端与亥姆霍兹线圈41的输出端连接,其输出端与计算机控制和处理单元8连接。温度实现单元7是带温度检测与显示装置的高低温度试验箱。其它结构与实施例1相同。
实施例3,参考图7所示,本实施例所有工作由人工操作。本实施例中感应电压检测和处理单元5是数字磁通计。温度实现单元7是带温度检测与显示装置的高低温度试验箱,不由计算机控制和处理单元8向温度实现单元7发出温度控制指令,控制加热装置72、冷却装置73进行工作。人工操作将样品盒2从亥姆霍兹线圈41中提拉出去,其它结构与实施例1相同。
一种在开路下永磁材料温度特性的测量方法,利用电磁感应法原理,使用亥姆霍兹线圈和磁通计等,准确测量永磁体的磁矩m、工作点的磁化强度Md、工作点的磁通密度Bd,以及永磁体所用永磁材料的顽磁Br以及磁通密度矫顽力HcB等温度系数以及不可逆损失。本发明推导了永磁体的磁矩m与这些参数之间的关系。 A method for measuring the temperature characteristics of permanent magnet materials in an open circuit, using the principle of electromagnetic induction, using Helmholtz coils and fluxmeters, etc., to accurately measure the magnetic moment m of permanent magnets, the magnetization M d at the working point, and the working The magnetic flux density B d of the point, and the temperature coefficient of the permanent magnetic material used in the permanent magnet B r and the magnetic flux density coercive force H cB and irreversible loss. The present invention derives the relationship between the magnetic moment m of a permanent magnet and these parameters.
该方法的原理基于电磁感应法。在亥姆霍兹线圈磁场均匀区内,永磁体看成是一磁偶极子。因此,处于开磁路状态、磁矩为m的永磁体在亥姆霍兹线圈中产生的感应电动势可以表示成[1]: The principle of the method is based on the electromagnetic induction method. In the homogeneous area of the Helmholtz coil magnetic field, the permanent magnet is regarded as a magnetic dipole. Therefore, the induced electromotive force generated in the Helmholtz coil by a permanent magnet with a magnetic moment m in an open magnetic circuit state can be expressed as [1] :
μ0Md=Bd+μ0Hd ......................................(11) μ 0 M d = B d + μ 0 H d ............................( 11)
式⑴中: In formula (1):
mz——磁矩m在亥姆霍兹线圈轴线上的分量,A·m2; m z ——the component of the magnetic moment m on the axis of the Helmholtz coil, A·m 2 ;
E——磁矩m在亥姆霍兹线圈中从t1瞬间(即开始时)到t2瞬间(即结束时)产生的感应电动势,V; E——The induced electromotive force generated by the magnetic moment m in the Helmholtz coil from the moment t 1 (that is, the beginning) to the moment t 2 (that is, the end), V;
C——亥姆霍兹线圈常数,m; C——Helmholtz coil constant, m;
——磁常数,μ0=4π×10-7H/m。 ——Magnetic constant, μ 0 =4π×10 -7 H/m.
根据法拉第电磁感应原理,由永磁体在亥姆霍兹线圈中的磁通量变化(△Φ),产生的感应电动势可以表示为: According to Faraday's principle of electromagnetic induction, the induced electromotive force generated by the change of the magnetic flux (△Φ) of the permanent magnet in the Helmholtz coil can be expressed as:
式⑵中: In formula (2):
ΔΦ——永磁体在亥姆霍兹线圈中的磁通量变化,Wb; ΔΦ——the magnetic flux change of the permanent magnet in the Helmholtz coil, Wb;
Φ1——永磁体在亥姆霍兹线圈中t1瞬间产生的磁通量,Wb; Φ 1 ——The magnetic flux generated by the permanent magnet in the Helmholtz coil at t 1 instant, Wb;
Φ2——永磁体在亥姆霍兹线圈中t2瞬间产生的磁通量,Wb; Φ 2 ——The magnetic flux generated by the permanent magnet in the Helmholtz coil at t 2 instant, Wb;
E——永磁体在亥姆霍兹线圈中产生的感应电动势,V; E——the induced electromotive force generated by the permanent magnet in the Helmholtz coil, V;
如果t1瞬间(即开始时)产生的磁通量Φ1=0Wb,t2瞬间(即结束时)产生的磁通量Φ2=Φ,则: If the magnetic flux Φ 1 = 0Wb generated at the instant t 1 (i.e. at the beginning), and the magnetic flux Φ 2 = Φ generated at the instant t 2 (i.e. at the end), then:
因此,根据式⑴和式⑶,通过测量永磁体在亥姆霍兹线圈中的磁通量变化,便能测量永磁体的磁矩m和磁矩的平均温度系数am,即: Therefore, according to formula (1) and formula (3), the magnetic moment m and the average temperature coefficient a m of the permanent magnet can be measured by measuring the change of the magnetic flux of the permanent magnet in the Helmholtz coil, namely:
式⑸中,由亥姆霍兹线圈和磁通计(电压积分器)分别测量在温度T1和T2下的磁通值Φ(T1)和Φ(T2),可以计算出永磁体的磁矩平均温度系数am。实际上,由此得到的温度系数是在温度T1和T2范围内的平均温度系数。 In formula (5), the magnetic flux values Φ(T 1 ) and Φ(T 2 ) at temperatures T 1 and T 2 are measured by the Helmholtz coil and the fluxmeter (voltage integrator), respectively, and the permanent magnet can be calculated The average temperature coefficient of magnetic moment a m . In practice, the resulting temperature coefficient is the average temperature coefficient over the range of temperatures T1 and T2 .
要得到在温度T1和T2范围内任意温度点的温度系数,在测量温度区域内,至少测量五个温度点的磁通量,然后利用最小二乘法原理将测量数据拟合成磁通与温度的多项式曲线,即: To obtain the temperature coefficient of any temperature point within the range of temperature T 1 and T 2 , measure the magnetic flux at least five temperature points in the measurement temperature area, and then use the principle of least squares to fit the measured data into the relationship between magnetic flux and temperature Polynomial curves, namely:
式⑹中: In formula (6):
n——磁通Φ(T1)与温度的多项式曲线的多项式最高价数; n——the polynomial highest valence of the polynomial curve of magnetic flux Φ(T 1 ) and temperature;
ai——其多项式的系数。 a i —coefficients of its polynomial.
任意温度点T的温度系数可表示为: The temperature coefficient of any temperature point T can be expressed as:
同理,由亥姆霍兹线圈和磁通计测量得到永磁体的不可逆损失,即: Similarly, the irreversible loss of the permanent magnet is measured by the Helmholtz coil and the fluxmeter, namely:
式⑻中: In formula (8):
m1——温度为T1时的磁矩,A·m2; m 1 ——magnetic moment when the temperature is T 1 , A·m 2 ;
m2——从温度T2恢复至温度T1时的磁矩,A·m2; m 2 ——magnetic moment when returning from temperature T 2 to temperature T 1 , A·m 2 ;
ηm——永磁体的不可逆损失,%。 η m ——Irreversible loss of permanent magnet, %.
根据磁导系数(或工作点)Pc的定义,磁导系数Pc为: According to the definition of permeability coefficient (or working point) P c , the permeability coefficient P c is:
式⑼中: In formula (9):
Bd——永磁体产生的磁感应强度,T; B d ——The magnetic induction intensity produced by the permanent magnet, T;
Hd——永磁体的内部退磁场强度,A·m-1。 H d ——the internal demagnetization field strength of the permanent magnet, A·m -1 .
根据磁化强度的定义,则磁化强度为: According to the definition of magnetization, the magnetization is:
式⑽中: In formula ⑽:
m——永磁体的磁矩,A·m2; m——Magnetic moment of permanent magnet, A·m 2 ;
V——永磁体的体积,m3; V——the volume of the permanent magnet, m 3 ;
ρ——永磁体的密度,kg·m-3; ρ——the density of the permanent magnet, kg·m -3 ;
mA——永磁体的质量,kg m A ——mass of permanent magnet, kg
M——永磁体的磁化强度,A·m-1。 M——The magnetization intensity of the permanent magnet, A·m -1 .
根据磁化强度与磁感应强度的关系,在永磁体工作点下,则有: According to the relationship between the magnetization intensity and the magnetic induction intensity, at the working point of the permanent magnet, there are:
式⑾中: In formula ⑾:
Md——永磁体的磁化强度,A·m-1。 M d ——the magnetization intensity of the permanent magnet, A·m -1 .
由于永磁材料的B-H退磁曲线近似为直线,其回复磁导率μr与顽磁Br、磁通密度矫顽力HcB以及BH能积的最大值(BH)max的关系为: Since the BH demagnetization curve of the permanent magnet material is approximately a straight line, the relationship between the recovery permeability μ r and the coercive force B r , the magnetic flux density coercive force H cB and the maximum value of the BH energy product (BH) max is:
根据式⑷和式⑽,由亥姆霍兹线圈和磁通计(电压积分器),可测量得到永磁体的磁通与永磁体磁化强度和磁感应强度的关系: According to formula ⑷ and formula ⑽, the relationship between the magnetic flux of the permanent magnet and the magnetization and magnetic induction of the permanent magnet can be measured by the Helmholtz coil and the fluxmeter (voltage integrator):
式⒁和⒂是使用亥姆霍兹线圈和磁通计测量永磁体磁化强度和磁感应强度的原理和方法。 Formulas ⒁ and ⒂ are the principles and methods for measuring the magnetization and magnetic induction of permanent magnets using Helmholtz coils and fluxmeters.
根据式⑼、⑿、⒀和式⒁,由亥姆霍兹线圈和磁通计(电压积分器),可测量得到永磁体的磁通与其材料的顽磁Br、磁通密度矫顽力HcB以及BH能积的最大值(BH)max的关系:式⒃、⒄和⒅分别是使用亥姆霍兹线圈和磁通计测量永磁体所用材料的顽磁、磁通密度矫顽力和能积的最大值的原理和方法。 According to formulas ⑼, ⑿, ⒀ and formula ⒁, the magnetic flux of the permanent magnet and the coercivity B r of the material, the magnetic flux density coercive force H The relationship between cB and the maximum value of the BH energy product (BH) max : Equations ⒃, ⒄ and ⒅ are the coercive force, magnetic flux density coercive force and energy The principle and method of the maximum value of the product.
根据以上原理以及温度系数的定义,利用亥姆霍兹线圈、磁通计以及温度实现装置,准确测量永磁体磁矩m、磁化强度Md、磁感应强度Bd以及其材料的顽磁Br、磁通密度矫顽力HcB和能积的最大值(BH)max等参数对应的温度系数,还可测量得到不可逆损失。 According to the above principles and the definition of temperature coefficient, using the Helmholtz coil, fluxmeter and temperature realization device, the magnetic moment m, magnetization M d , magnetic induction B d of the permanent magnet and the remanence B r of the material are accurately measured. The temperature coefficient corresponding to parameters such as magnetic flux density coercive force H cB and energy product maximum (BH) max can also be measured to obtain irreversible loss.
以上内容是结合具体的优选实施方式对本发明所作的进一步详细说明,不能认定本发明的具体实施只局限于这些说明。对于本发明所属技术领域的普通技术人员来说,在不脱离本发明构思的前提下,还可以做出若干简单推演或替换,都应当视为属于本发明的保护范围。 The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and it cannot be assumed that the specific implementation of the present invention is limited to these descriptions. For those of ordinary skill in the technical field of the present invention, without departing from the concept of the present invention, some simple deduction or replacement can be made, which should be regarded as belonging to the protection scope of the present invention. the
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CN105588958A (en) * | 2016-01-22 | 2016-05-18 | 中山大学 | Rapid multifunctional electronic component temperature characteristic measuring instrument and testing cavity |
CN105785291A (en) * | 2014-12-25 | 2016-07-20 | 北京中科三环高技术股份有限公司 | Permanent magnet material magnetic flux temperature stability measuring device and method thereof |
CN105823993A (en) * | 2016-03-11 | 2016-08-03 | 宁波市计量测试研究院(宁波市衡器管理所) | Magnetic declination measuring system |
CN106932740A (en) * | 2015-12-31 | 2017-07-07 | 北京中科三环高技术股份有限公司 | Permanent magnet magnetic flux device for investigating temperature coefficient and method |
CN109613457A (en) * | 2018-12-29 | 2019-04-12 | 陕西宝成航空仪表有限责任公司 | Magnet steel method for testing performance |
CN110471009A (en) * | 2018-05-11 | 2019-11-19 | 中国科学院宁波材料技术与工程研究所 | Device and method for measuring magnetic flux temperature characteristics in wide temperature range |
CN112269156A (en) * | 2020-10-23 | 2021-01-26 | 河北工业大学 | Permanent magnet magnetic property temperature coefficient measuring and variable temperature/high temperature permanent magnet magnetic property monitoring device |
CN112730595A (en) * | 2020-12-18 | 2021-04-30 | 哈尔滨工业大学 | Magnetic flux online measurement method of permanent magnet material in high-temperature state |
CN113126008A (en) * | 2019-12-31 | 2021-07-16 | 北京中科三环高技术股份有限公司 | Method for determining permeability coefficient |
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CN105785291A (en) * | 2014-12-25 | 2016-07-20 | 北京中科三环高技术股份有限公司 | Permanent magnet material magnetic flux temperature stability measuring device and method thereof |
CN106932740A (en) * | 2015-12-31 | 2017-07-07 | 北京中科三环高技术股份有限公司 | Permanent magnet magnetic flux device for investigating temperature coefficient and method |
CN105588958A (en) * | 2016-01-22 | 2016-05-18 | 中山大学 | Rapid multifunctional electronic component temperature characteristic measuring instrument and testing cavity |
CN105588958B (en) * | 2016-01-22 | 2018-10-09 | 中山大学 | A kind of quick multifunctional electronic component temperature characteristic measuring instrument and test cavity |
CN105823993A (en) * | 2016-03-11 | 2016-08-03 | 宁波市计量测试研究院(宁波市衡器管理所) | Magnetic declination measuring system |
CN110471009A (en) * | 2018-05-11 | 2019-11-19 | 中国科学院宁波材料技术与工程研究所 | Device and method for measuring magnetic flux temperature characteristics in wide temperature range |
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CN109613457A (en) * | 2018-12-29 | 2019-04-12 | 陕西宝成航空仪表有限责任公司 | Magnet steel method for testing performance |
CN109613457B (en) * | 2018-12-29 | 2020-12-25 | 陕西宝成航空仪表有限责任公司 | Magnetic steel performance detection method |
CN113126008B (en) * | 2019-12-31 | 2022-05-31 | 北京中科三环高技术股份有限公司 | Method for determining permeability coefficient |
CN113126008A (en) * | 2019-12-31 | 2021-07-16 | 北京中科三环高技术股份有限公司 | Method for determining permeability coefficient |
CN112269156B (en) * | 2020-10-23 | 2022-07-26 | 河北工业大学 | Permanent magnet magnetic property temperature coefficient measuring and variable temperature/high temperature permanent magnet magnetic property monitoring device |
CN112269156A (en) * | 2020-10-23 | 2021-01-26 | 河北工业大学 | Permanent magnet magnetic property temperature coefficient measuring and variable temperature/high temperature permanent magnet magnetic property monitoring device |
CN112730595A (en) * | 2020-12-18 | 2021-04-30 | 哈尔滨工业大学 | Magnetic flux online measurement method of permanent magnet material in high-temperature state |
CN113325346A (en) * | 2021-06-15 | 2021-08-31 | 叶陈金 | Permanent magnet motor permanent magnet tolerance temperature loss magnetic test device |
CN113325346B (en) * | 2021-06-15 | 2023-11-17 | 山西高米麦恩工业科技有限公司 | Temperature-resistant loss-of-field test device for permanent magnet of permanent magnet motor |
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