CN103454553A - Secondary side phase checking device of voltage transformer - Google Patents
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Abstract
本发明公开了一种电力系统用的电压互感器二次侧核相装置,包括,第一组三相接线柱ABC、第二组三相接线柱A1B1C1、三个数字电压表和三个数字相位表。有益效果是,使用极为方便,现场作业时,能够实行单人操作,能够核对电压互感器二次侧的每两相电压之间的幅值和相位,数值显示精确,节约工时,提高工作效率。
The invention discloses a secondary-side verification device of a voltage transformer used in a power system, which comprises a first group of three-phase terminal ABC, a second group of three-phase terminal A1B1C1, three digital voltmeters and three digital phase surface. The beneficial effect is that it is extremely convenient to use, and can be operated by a single person during on-site operations, and can check the amplitude and phase between each two-phase voltage on the secondary side of the voltage transformer, and the numerical display is accurate, saving man-hours and improving work efficiency.
Description
技术领域 technical field
本发明涉及电力行业系统继电保护专业技术领域;特别是涉及一种电压互感器的二次侧核相装置。 The invention relates to the technical field of system relay protection in the electric power industry; in particular, it relates to a secondary-side phase verification device of a voltage transformer.
背景技术 Background technique
电力行业系统使用的电压互感器,实际上是一个带铁芯的变压器。它主要由一、二次线圈、铁芯和绝缘层组成。当在一次绕组上施加一个电压U1时,在铁芯中就产生一个磁通φ,根据电磁感应定律,则在二次绕组中就产生一个二次电压U2。改变一次或二次绕组的匝数,可以产生不同的一次侧电压与二次侧电压比,这就可以组成不同比例的电压互感器。电压互感器将一次侧的高电压按比例转换成二次侧的低电压,即100V,电压互感器一次侧接在一次系统中,电压互感器二次侧接测量仪表、继电保护系统中。电压互感器主要是电磁式的(电容式电压互感器应用广泛),另有非电磁式的,如电子式、光电式等。 电压互感器的运行情况,相当于二次侧开路的变压器,其负载为阻抗较大的测量仪表。电压互感器的作用是,将一次侧的高电压按比例关系变换成100V或更低等级的标准的二次侧电压,供保护、计量和仪表装置使用。同时,使用电压互感器,可以将一次侧的高电压与电气工作人员隔离。电压互感器虽然也是按照电磁感应原理工作的设备,但它的电磁结构关系与电流互感器相比正好相反。电压互感器二次侧回路是高阻抗回路,二次侧电流的大小由回路的阻抗决定。当二次侧负载阻抗减小时,二次侧电流增大,使得一次侧的电流自动增大一个分量来满足一、二次侧之间的电磁平衡关系。可以说,电压互感器是一个被限定结构和使用形式的特殊变压器。电压互感器的接线方式很多,常见的有以下几种: (1) 用一台单相电压互感器来测量某一相对地电压或相间电压的接线方式。 (2) 用两台单相互感器接成不完全星形,也称V-V接线,用来测量各相间电压,但不能测量相线对地电压,广泛应用在20KV以下中性点不接地或经消弧线圈接地的电网中。 (3) 用三台单相三绕组电压互感器构成YN,yn,d0或YN,y,d0的接线形式,广泛应用于3~220KV系统中,其二次绕组用于测量相间电压和相对地电压,辅助二次绕组接成开口三角形,供接入交流电网绝缘监视仪表和继电器使用。用一台三相五柱式电压互感器代替上述三个单相三绕组电压互感器构成的接线,一般只用于3~15KV电力系统。 (4) 电容式电压互感器接线形式。 在中性点不接地或经消弧线圈接地的系统中,为了测量相对地电压,电压互感器一次绕组必须接成星形接地的方式。 在3~60KV电网中,通常采用三只单相三绕组电压互感器,或者一只三相五柱式电压互感器的接线形式。必须指出,不能用三相三柱式电压互感器做这种测量。当系统发生单相接地短路时,在互感器的三相中将有零序电流通过,产生大小相等、相位相同的零序磁通。在三相三柱式互感器中,零序磁通,只能通过磁阻很大的气隙和铁外壳形成闭合磁路,零序电流很大,使互感器绕组过热,甚至损坏设备。而在三相五柱式电压互感器中,零序磁通可通过两侧的铁芯构成回路,磁阻较小,所以零序电流值不大,对互感器不会造成损害。电流互感器二次侧不能开路的原因是,电流互感器的一次电流很大,如果二次出现开路就相当于把一次侧的电流直接加到二次侧,轻则造成互感器的烧毁,使电流表读数不准确,重则造成烧毁电器设备和威胁人身安全。 The voltage transformer used in the power industry system is actually a transformer with an iron core. It is mainly composed of primary and secondary coils, iron core and insulating layer. When a voltage U1 is applied to the primary winding, a magnetic flux φ is generated in the iron core, and according to the law of electromagnetic induction, a secondary voltage U2 is generated in the secondary winding. Changing the number of turns of the primary or secondary winding can produce different ratios of primary side voltage to secondary side voltage, which can form voltage transformers with different ratios. The voltage transformer converts the high voltage of the primary side into the low voltage of the secondary side in proportion, that is, 100V. The primary side of the voltage transformer is connected to the primary system, and the secondary side of the voltage transformer is connected to the measuring instrument and the relay protection system. Voltage transformers are mainly electromagnetic (capacitive voltage transformers are widely used), and non-electromagnetic, such as electronic, photoelectric, etc. The operation of the voltage transformer is equivalent to a transformer with an open circuit on the secondary side, and its load is a measuring instrument with a large impedance. The function of the voltage transformer is to convert the high voltage of the primary side into a standard secondary side voltage of 100V or lower in proportion, for protection, metering and instrumentation devices. At the same time, with the use of voltage transformers, the high voltage on the primary side can be isolated from electrical workers. Although the voltage transformer is also a device that works according to the principle of electromagnetic induction, its electromagnetic structure relationship is just the opposite of that of the current transformer. The secondary side circuit of the voltage transformer is a high impedance circuit, and the magnitude of the secondary side current is determined by the impedance of the circuit. When the load impedance of the secondary side decreases, the current of the secondary side increases, so that the current of the primary side automatically increases by a component to satisfy the electromagnetic balance relationship between the primary and secondary sides. It can be said that a voltage transformer is a special transformer with a limited structure and use form. There are many wiring methods for voltage transformers, and the common ones are as follows: (1) Use a single-phase voltage transformer to measure a certain phase-to-ground voltage or phase-to-phase voltage. (2) Use two single-phase inductors to form an incomplete star, also known as V-V connection, to measure the voltage between phases, but not to measure the voltage between phase lines and ground. It is widely used in ungrounded neutral points below 20KV or through In the grid where the arc suppression coil is grounded. (3) Use three single-phase three-winding voltage transformers to form the wiring form of YN, yn, d0 or YN, y, d0, which is widely used in 3~220KV systems, and its secondary winding is used to measure phase-to-phase voltage and relative ground Voltage, the auxiliary secondary winding is connected into an open triangle, which is used for insulation monitoring instruments and relays connected to the AC grid. A three-phase five-column voltage transformer is used to replace the above three single-phase three-winding voltage transformers for wiring, which is generally only used in 3~15KV power systems. (4) Wiring form of capacitor voltage transformer. In the system where the neutral point is not grounded or grounded by the arc suppressing coil, in order to measure the voltage relative to the ground, the primary winding of the voltage transformer must be connected in a star-shaped grounding manner. In the 3~60KV power grid, three single-phase three-winding voltage transformers or one three-phase five-column voltage transformer are usually used in the wiring form. It must be pointed out that this measurement cannot be done with three-phase three-column voltage transformers. When a single-phase ground short circuit occurs in the system, zero-sequence current will pass through the three phases of the transformer, generating zero-sequence magnetic flux with equal magnitude and same phase. In the three-phase three-column transformer, the zero-sequence flux can only form a closed magnetic circuit through the air gap with a large reluctance and the iron shell, and the zero-sequence current is very large, which will cause the transformer winding to overheat and even damage the equipment. In the three-phase five-column voltage transformer, the zero-sequence flux can form a circuit through the iron cores on both sides, and the reluctance is small, so the zero-sequence current value is not large and will not cause damage to the transformer. The reason why the secondary side of the current transformer cannot be opened is that the primary current of the current transformer is very large. If the secondary side is open, it is equivalent to directly adding the current from the primary side to the secondary side, which may cause the transformer to burn out. Ammeter readings are inaccurate, and in severe cases, electrical equipment may be burned and personal safety may be threatened.
目前,现场电压互感器二次侧核相时没有专用的测量装置,只是用数字式万用表进行每相的测量,核对每两相电压之间的幅值,判断电压互感器二次接线是否正确,不能对每两相电压之间的相位差进行测量,且需要两人配合操作完成,工作效率低。 At present, there is no special measuring device for phase verification on the secondary side of the field voltage transformer, but a digital multimeter is used to measure each phase, to check the amplitude between the voltages of each two phases, and to judge whether the secondary wiring of the voltage transformer is correct. The phase difference between each two-phase voltage cannot be measured, and two people are required to cooperate to complete the operation, and the work efficiency is low.
发明内容 Contents of the invention
本发明所要解决的技术问题是,提供一种能够核对每两相电压之间的幅值和相位节约工时的电压互感器的二次侧核相装置。 The technical problem to be solved by the present invention is to provide a secondary side phase checking device of a voltage transformer capable of checking the amplitude and phase between each two-phase voltage and saving man-hours.
本发明所采用的技术方案是,一种电压互感器二次侧核相装置,其特征在于,包括,第一组三相接线柱ABC、第二组三相接线柱A1B1C1、三个数字电压表和三个数字相位表; The technical solution adopted in the present invention is a phase verification device on the secondary side of a voltage transformer, which is characterized in that it includes the first group of three-phase binding posts ABC, the second group of three-phase binding posts A1B1C1, and three digital voltmeters and three digital phase meters;
第一数字电压表和第一数字相位表的输入端分别并联连接,所述第一组三相电A相接线柱与第一数字电压表和第一数字相位表的并联输入的一端电连接,所述第二组三相电A1相接线柱与第一数字电压表和第一数字相位表的并联输入的另一端电连接; The input ends of the first digital voltmeter and the first digital phase meter are respectively connected in parallel, and the first group of three-phase electric phase A terminal is electrically connected with one end of the parallel input of the first digital voltmeter and the first digital phase meter, The second group of three-phase electricity A1-phase terminal is electrically connected to the other end of the parallel input of the first digital voltmeter and the first digital phase meter;
第二数字电压表和第二数字相位表的输入端分别并联连接,所述第一组三相电B相接线柱与第二数字电压表和第二数字相位表的并联输入的一端电连接,所述第二组三相电B1相接线柱与第二数字电压表和第二数字相位表的并联输入的另一端电连接; The input terminals of the second digital voltmeter and the second digital phase meter are respectively connected in parallel, and the first group of three-phase electric B-phase terminal is electrically connected with one end of the parallel input of the second digital voltmeter and the second digital phase meter, The second group of three-phase electricity B1 phase terminal is electrically connected to the other end of the parallel input of the second digital voltmeter and the second digital phase meter;
第三数字电压表和第三数字相位表的输入端分别并联连接,所述第一组三相电C相接线柱与第三数字电压表和第三数字相位表的并联输入的一端电连接,所述第二组三相电C1相接线柱与第三数字电压表和第三数字相位表的并联输入的另一端电连接。 The input terminals of the third digital voltmeter and the third digital phase meter are respectively connected in parallel, and the first group of three-phase electric phase C terminal is electrically connected with one end of the parallel input of the third digital voltmeter and the third digital phase meter, The second group of three-phase electricity C1-phase terminal is electrically connected to the other end of the parallel input of the third digital voltmeter and the third digital phase meter.
本发明的有益效果是,使用方便,现场作业时能够实行单人操作,能够核对每两相电压之间的幅值和相位,数值显示精确,节约工时,提高工作效率。 The beneficial effect of the invention is that it is easy to use, can be operated by a single person during on-site operation, can check the amplitude and phase of each two-phase voltage, can display accurate values, save man-hours, and improve work efficiency.
附图说明 Description of drawings
图1是本发明电压互感器二次侧核相装置组成结构示意图。 Fig. 1 is a schematic diagram of the composition and structure of the secondary side nuclear phase device of the voltage transformer of the present invention.
具体实施方式 Detailed ways
下面结合附图和具体实施方式对本发明作进一步详细说明: Below in conjunction with accompanying drawing and specific embodiment the present invention is described in further detail:
如图1所示,本发明电压互感器二次侧核相装置,包括,第一组三相接线柱ABC、第二组三相接线柱A1B1C1、三个数字电压表和三个数字相位表; As shown in Figure 1, the phase verification device on the secondary side of the voltage transformer of the present invention includes a first group of three-phase terminal ABC, a second group of three-phase terminal A1B1C1, three digital voltmeters and three digital phase meters;
第一数字电压表和第一数字相位表的输入端分别并联连接,所述第一组三相电A相接线柱与第一数字电压表和第一数字相位表的并联输入的一端电连接,所述第二组三相电A1相接线柱与第一数字电压表和第一数字相位表的并联输入的另一端电连接。 The input ends of the first digital voltmeter and the first digital phase meter are respectively connected in parallel, and the first group of three-phase electric phase A terminal is electrically connected with one end of the parallel input of the first digital voltmeter and the first digital phase meter, The second group of three-phase electricity A1-phase terminal is electrically connected to the other end of the parallel input of the first digital voltmeter and the first digital phase meter.
第二数字电压表和第二数字相位表的输入端分别并联连接,所述第一组三相电B相接线柱与第二数字电压表和第二数字相位表的并联输入的一端电连接,所述第二组三相电B1相接线柱与第二数字电压表和第二数字相位表的并联输入的另一端电连接。 The input terminals of the second digital voltmeter and the second digital phase meter are respectively connected in parallel, and the first group of three-phase electric B-phase terminal is electrically connected with one end of the parallel input of the second digital voltmeter and the second digital phase meter, The second group of three-phase electricity B1-phase terminal is electrically connected to the other end of the parallel input of the second digital voltmeter and the second digital phase meter.
第三数字电压表和第三数字相位表的输入端分别并联连接,所述第一组三相电C相接线柱与第三数字电压表和第三数字相位表的并联输入的一端电连接,所述第二组三相电C1相接线柱与第三数字电压表和第三数字相位表的并联输入的另一端电连接。 The input terminals of the third digital voltmeter and the third digital phase meter are respectively connected in parallel, and the first group of three-phase electric phase C terminal is electrically connected with one end of the parallel input of the third digital voltmeter and the third digital phase meter, The second group of three-phase electricity C1-phase terminal is electrically connected to the other end of the parallel input of the third digital voltmeter and the third digital phase meter.
本发明采用数字表显示被核交流电的幅度和相位差的数值,直观准确,装置两侧装设两组ABC三相接线柱,通过测试用连接导线,分别接入两组电压互感器二次侧,按照对应相别分别接线,对两组电压互感器二次侧每相电压进行测量,能够方便显示数值。现场作业时能够实行单人操作,不仅能够核对每两相电压之间的幅值,还能核对每两相电压之间的相位,数值显示精确,节约工时,提高工作效率。 The invention adopts a digital meter to display the value of the amplitude and phase difference of the verified alternating current, which is intuitive and accurate. Two sets of ABC three-phase terminal posts are installed on both sides of the device, and are respectively connected to two sets of secondary sides of voltage transformers through connecting wires for testing. , respectively connect according to the corresponding phases, and measure the voltage of each phase on the secondary side of the two sets of voltage transformers, which can conveniently display the values. One-person operation can be implemented during on-site operations, not only can check the amplitude between each two-phase voltage, but also check the phase between each two-phase voltage, the numerical display is accurate, saving man-hours and improving work efficiency.
测量时要注意极性的正确性,为了确保人在接触测量仪表和继电器时的安全,电压互感器二次绕组必须有一点接地。因为接地后,当一次和二次绕组间的绝缘损坏时,可以防止仪表和继电器出现高电压危及人身安全。电压互感器二次侧不允许短路。由于电压互感器内阻抗很小,若二次回路短路时,会出现很大的电流,将损坏二次设备甚至危及人身安全。接在电压互感器二次侧负荷的容量应合适,接在电压互感器二次侧的负荷不应超过其额定容量,否则,会使互感器的误差增大,难以达到测量的正确性。 Pay attention to the correctness of the polarity when measuring. In order to ensure the safety of people when they are in contact with measuring instruments and relays, the secondary winding of the voltage transformer must be grounded at one point. Because after grounding, when the insulation between the primary and secondary windings is damaged, it can prevent the high voltage of the instrument and relay from endangering personal safety. The secondary side of the voltage transformer is not allowed to be short-circuited. Since the internal impedance of the voltage transformer is very small, if the secondary circuit is short-circuited, a large current will appear, which will damage the secondary equipment and even endanger personal safety. The capacity of the load connected to the secondary side of the voltage transformer should be appropriate, and the load connected to the secondary side of the voltage transformer should not exceed its rated capacity, otherwise, the error of the transformer will increase and it will be difficult to achieve the accuracy of the measurement. the
值得指出的是,本发明的保护范围并不局限于上述具体实例方式,根据本发明的基本技术构思,也可用基本相同的结构,可以实现本发明的目的,只要本领域普通技术人员无需经过创造性劳动,即可联想到的实施方式,均属于本发明的保护范围。 It is worth pointing out that the scope of protection of the present invention is not limited to the above-mentioned specific examples. According to the basic technical concept of the present invention, basically the same structure can also be used to achieve the purpose of the present invention, as long as those of ordinary skill in the art do not need to be creative Labor, that is, the conceivable implementation modes, all belong to the protection scope of the present invention.
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105510714A (en) * | 2015-12-18 | 2016-04-20 | 国家电网公司 | Intelligent substation pressure transmitter secondary automatic phase tester |
CN106772194A (en) * | 2016-12-26 | 2017-05-31 | 国网山东省电力公司青岛供电公司 | A kind of voltage transformer secondary voltage nuclear-phase method, device and detection means |
CN107329007A (en) * | 2017-06-09 | 2017-11-07 | 国网上海市电力公司 | A kind of universal secondary nuclear phase instrument for transformer station |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101614771A (en) * | 2009-07-22 | 2009-12-30 | 天津市电力公司 | Detection method of digital substation PT secondary nuclear phase checking |
CN102680807A (en) * | 2012-07-10 | 2012-09-19 | 江苏省电力公司电力科学研究院 | Optical fiber digitized remote phase-checking system and phase-checking method thereof |
-
2013
- 2013-08-23 CN CN2013103731945A patent/CN103454553A/en active Pending
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101614771A (en) * | 2009-07-22 | 2009-12-30 | 天津市电力公司 | Detection method of digital substation PT secondary nuclear phase checking |
CN102680807A (en) * | 2012-07-10 | 2012-09-19 | 江苏省电力公司电力科学研究院 | Optical fiber digitized remote phase-checking system and phase-checking method thereof |
Non-Patent Citations (3)
Title |
---|
杨建堂 等: "两台变压器并联运行用电压表、相序表、进行核相", 《中国电力教育》 * |
邓贻名: "电力系统核相分析与应用", 《农村电气化》 * |
陈辉 等: "电压互感器的二次回路核相及接线", 《科技资讯》 * |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105510714A (en) * | 2015-12-18 | 2016-04-20 | 国家电网公司 | Intelligent substation pressure transmitter secondary automatic phase tester |
CN106772194A (en) * | 2016-12-26 | 2017-05-31 | 国网山东省电力公司青岛供电公司 | A kind of voltage transformer secondary voltage nuclear-phase method, device and detection means |
CN107329007A (en) * | 2017-06-09 | 2017-11-07 | 国网上海市电力公司 | A kind of universal secondary nuclear phase instrument for transformer station |
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