CN107167758B - Transformer ratio and polarity tester with waveform display function - Google Patents
Transformer ratio and polarity tester with waveform display function Download PDFInfo
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- CN107167758B CN107167758B CN201710560723.0A CN201710560723A CN107167758B CN 107167758 B CN107167758 B CN 107167758B CN 201710560723 A CN201710560723 A CN 201710560723A CN 107167758 B CN107167758 B CN 107167758B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R35/00—Testing or calibrating of apparatus covered by the other groups of this subclass
- G01R35/02—Testing or calibrating of apparatus covered by the other groups of this subclass of auxiliary devices, e.g. of instrument transformers according to prescribed transformation ratio, phase angle, or wattage rating
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/20—Measuring number of turns; Measuring transformation ratio or coupling factor of windings
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/72—Testing of electric windings
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Abstract
带波形显示功能的互感器变比、极性测试仪属于电力系统继电保护试验仪器技术领域，尤其涉及一种带波形显示功能的互感器变比、极性测试仪。本发明提供一种使用方便、测试可靠的带波形显示功能的互感器变比、极性测试仪。本发明包括逆变器、电池、电压调节器和带有波形显示功能的能够测量电压互感器一次加入电压有效值及电压互感器二次电压输出值的测量表计，其结构要点逆变器的电源输入端与电池相连，逆变器的电源输出端与电压调节器的电源输入端相连，电压调节器的电源输出端与电压互感器一次线圈相连，电压互感器一次线圈与测量表计一次线圈测量端相连，电压互感器二次线圈与测量表计二次线圈测量端相连，测量表计电源端与电池相连。
A transformer ratio and polarity tester with a waveform display function belongs to the technical field of power system relay protection test instruments, and in particular relates to a transformer ratio and polarity tester with a waveform display function. The invention provides a transformer transformation ratio and polarity tester with waveform display function which is convenient to use and reliable in testing. The invention includes an inverter, a battery, a voltage regulator and a measuring meter with a waveform display function capable of measuring the effective value of the primary voltage added to the voltage transformer and the secondary voltage output value of the voltage transformer. The power input terminal is connected to the battery, the power output terminal of the inverter is connected to the power input terminal of the voltage regulator, the power output terminal of the voltage regulator is connected to the primary coil of the voltage transformer, and the primary coil of the voltage transformer is connected to the primary coil of the measuring meter. The measuring end is connected, the secondary coil of the voltage transformer is connected with the measuring end of the secondary coil of the measuring meter, and the power supply end of the measuring meter is connected with the battery.
Description
技术领域technical field
本发明属于电力系统继电保护试验仪器技术领域，尤其涉及一种带波形显示功能的互感器变比、极性测试仪。The invention belongs to the technical field of power system relay protection test instruments, in particular to a transformer ratio and polarity tester with a waveform display function.
背景技术Background technique
电流、电压互感器在正式带电运行前的“极性”、“变比”校验工作必不可少、校验结果的正确性又非常重要。The verification of the "polarity" and "transformation ratio" of the current and voltage transformers before the official live operation is indispensable, and the correctness of the verification results is very important.
传统的电流互感器(CT)极性试验方法是：采用干电池点极性的方法。The traditional current transformer (CT) polarity test method is to use the method of dry cell point polarity.
如图1：CT一次侧开关K合闸瞬间，CT二次感应电流从K1流出，经电流表流回K2端，电流从直流电流表的+端流入，从-端流出，直流电流表指针正向偏转，反之断开K的瞬间，电流表指针反向偏转。说明电流互感器一次线圈的L1端与二次线圈的K1端为同极性端。这种校验极性的方法，试验环节多、效果不明显、试验结果容易因接线错误或方法不对头而出错。As shown in Figure 1: When the CT primary side switch K is closed, the CT secondary induced current flows out from K1 and flows back to the K2 terminal through the ammeter. The current flows in from the + terminal of the DC ammeter and flows out from the - terminal. On the contrary, when K is disconnected, the pointer of the ammeter deflects in the opposite direction. Explain that the L1 end of the primary coil of the current transformer and the K1 end of the secondary coil are the same polarity ends. This method of verifying the polarity has many test links, the effect is not obvious, and the test results are prone to errors due to incorrect wiring or incorrect methods.
传统的电流互感器(CT)变比试验方法是：在CT的一次线圈通入大电流i1,再测量CT二次电流i2，计算出i1与i2的比值就是CT的变比。该方法的缺点是：实验仪器笨重，达到几十斤、不易携带，试验线粗、重，试验结果的精度差，工作量大。The traditional current transformer (CT) transformation ratio test method is: pass a large current i1 to the primary coil of the CT, and then measure the CT secondary current i2, and calculate the ratio of i1 to i2 is the CT transformation ratio. The disadvantages of this method are: the experimental instrument is cumbersome, reaching dozens of kilograms, not easy to carry, the test line is thick and heavy, the accuracy of the test results is poor, and the workload is large.
发明内容SUMMARY OF THE INVENTION
本发明就是针对上述问题，提供一种使用方便、测试可靠的带波形显示功能的互感器变比、极性测试仪。In view of the above problems, the present invention provides a transformer ratio and polarity tester with a waveform display function that is convenient to use and reliable in testing.
为实现上述目的，本发明采用如下技术方案，本发明包括逆变器、电池、电压调节器和带有波形显示功能的能够测量电压互感器一次加入电压有效值及电压互感器二次电压输出值的测量表计，其结构要点逆变器的电源输入端与电池相连，逆变器的电源输出端与电压调节器的电源输入端相连，电压调节器的电源输出端与电压互感器一次线圈相连，电压互感器一次线圈与测量表计一次线圈测量端相连，电压互感器二次线圈与测量表计二次线圈测量端相连，测量表计电源端与电池相连。In order to achieve the above purpose, the present invention adopts the following technical solutions. The present invention includes an inverter, a battery, a voltage regulator, and a voltage transformer with a waveform display function capable of measuring the effective value of the primary voltage added by the voltage transformer and the secondary voltage output value of the voltage transformer. The main point of its structure is that the power input terminal of the inverter is connected to the battery, the power output terminal of the inverter is connected to the power input terminal of the voltage regulator, and the power output terminal of the voltage regulator is connected to the primary coil of the voltage transformer. The primary coil of the voltage transformer is connected to the measuring end of the primary coil of the measuring meter, the secondary coil of the voltage transformer is connected to the measuring end of the secondary coil of the measuring meter, and the power end of the measuring meter is connected to the battery.
测量表计包括交流输入部分、波形输出及相位检测电路、整流滤波电路、模数转换电路、主控部分、稳压电路和显示屏幕，交流输入部分的输入端口分别与测量表计一次线圈测量端、测量表计二次线圈测量端、增益切换控制部分输出端口相连，交流输入部分的输出端口分别与整流滤波电路的输入端口、波形输出及相位检测电路的输入端口相连，整流滤波电路的输出端口与模数转换电路的输入端口相连。The measuring meter includes an AC input part, a waveform output and phase detection circuit, a rectifier filter circuit, an analog-to-digital conversion circuit, a main control part, a voltage regulator circuit and a display screen. , The measurement terminal of the secondary coil of the measuring meter is connected to the output port of the gain switching control part, the output port of the AC input part is connected to the input port of the rectifier filter circuit, the waveform output and the input port of the phase detection circuit respectively, and the output port of the rectifier filter circuit is connected. Connect with the input port of the analog-to-digital conversion circuit.
主控部分分别与增益切换控制部分的输入端口、波形输出及相位检测电路的输出端口、模数转换电路的输出端口、显示屏幕、稳压电路相连。The main control part is respectively connected with the input port of the gain switching control part, the output port of the waveform output and the phase detection circuit, the output port of the analog-digital conversion circuit, the display screen and the voltage regulator circuit.
作为一种优选方案，本发明所述逆变器为功率500W或1000W、输入为直流12伏、输出为交流220伏正弦波的逆变器，电池为12伏、20-100安时的锂离子电池或铅酸免维护电池，电压调节器为输入220交流、输出0-250伏的电压功率500W的电压调整器。As a preferred solution, the inverter of the present invention is an inverter with a power of 500W or 1000W, an input of 12 volts DC, and an output of a sine wave of 220 volts of AC, and the battery is a lithium ion of 12 volts and 20-100 amp hours. Battery or lead-acid maintenance-free battery, the voltage regulator is a voltage regulator with an input of 220 AC and an output voltage of 0-250 volts and a power of 500W.
作为另一种优选方案，本发明所述主控部分包括STM32F103VDT6芯片U7和STM32F103VDT6芯片U21。As another preferred solution, the main control part of the present invention includes STM32F103VDT6 chip U7 and STM32F103VDT6 chip U21.
波形输出及相位检测电路包括opa2333芯片UA7和opa2333芯片UA8。The waveform output and phase detection circuit includes opa2333 chip UA7 and opa2333 chip UA8.
模数转换电路包括ad7705芯片U1。The analog-to-digital conversion circuit includes the ad7705 chip U1.
交流输入部分包括opa2333芯片UA1和opa2333芯片UA2，UA1的3脚分别与二极管D1阳极、二极管D2阴极、电阻R4一端、电阻R9一端、电阻R11一端、电阻R14一端、电阻R16一端相连，电阻R4另一端依次通过电阻R5、电容C5与电压互感器一次线圈一端相连，二极管D1阴极接AVCC5V端，二极管D2阳极接AGND端；电阻R9另一端与SN74LVC1G3157DCKR芯片U2的1脚相连，U2的6脚与U7的53脚相连。The AC input part includes opa2333 chip UA1 and opa2333 chip UA2. The 3 pins of UA1 are respectively connected to the anode of diode D1, the cathode of diode D2, one end of resistor R4, one end of resistor R9, one end of resistor R11, one end of resistor R14, one end of resistor R16, and the other end of resistor R4. One end is connected to one end of the primary coil of the voltage transformer through the resistor R5 and the capacitor C5 in turn, the cathode of the diode D1 is connected to the AVCC5V terminal, the anode of the diode D2 is connected to the AGND terminal; the other end of the resistor R9 is connected to the 1 pin of the SN74LVC1G3157DCKR chip U2, and the 6 pin of U2 is connected to U7 connected to pin 53.
电阻R11另一端与SN74LVC1G3157DCKR芯片U3的1脚相连，U3的6脚与U7的52脚相连。The other end of resistor R11 is connected to
电阻R14另一端与SN74LVC1G3157DCKR芯片U4的1脚相连，U4的6脚与U7的51脚相连。The other end of resistor R14 is connected to
电阻R16另一端与SN74LVC1G3157DCKR芯片U6的1脚相连，U6的6脚与U7的48脚相连。The other end of resistor R16 is connected to
UA1的1脚分别与电阻R2一端、电容C6一端、电阻R12一端相连，电阻R12另一端分别与UA1的2脚、电阻R15一端相连，电阻R15另一端接2.5V，阻R2另一端分别与UA7的3脚、电容C21一端相连；电容C6另一端通过R8分别与电阻R7一端、电容C8一端、电容C10一端、电阻R13一端、UA1的6脚相连，电阻R7另一端分别与电阻R6一端、电容C8另一端、二极管D4阴极相连，电阻R6另一端分别与电容C7一端、电阻R3一端相连，电阻R3另一端分别与电容C9一端、U1的7脚相连，电容C9另一端分别与电容C7另一端、U1的8脚、电容C10另一端、电阻R13另一端、二极管D5阳极相连，二极管D5阴极分别与二极管D4阳极、UA1的7脚相连，UA1的5脚接2.5V电压并通过电容C146接AGND。
UA2的3脚分别与二极管D6阳极、二极管D7阴极、电阻R20一端、电阻R26一端、电阻R27一端、电阻R31一端、电阻R33一端相连，电阻R20另一端依次通过电阻R21、电容C24与电压互感器二次线圈一端相连，二极管D6阴极接AVCC5V端，二极管D7阳极接AGND端；电阻R26另一端与SN74LVC1G3157DCKR芯片U9的1脚相连，U9的6脚与U7的47脚相连。The 3 pins of UA2 are respectively connected with the anode of diode D6, the cathode of diode D7, one end of resistor R20, one end of resistor R26, one end of resistor R27, one end of resistor R31 and one end of resistor R33, and the other end of resistor R20 is connected to the voltage transformer through resistor R21 and capacitor C24 in turn. One end of the secondary coil is connected, the cathode of the diode D6 is connected to the AVCC5V terminal, and the anode of the diode D7 is connected to the AGND terminal; the other end of the resistor R26 is connected to the 1 pin of the SN74LVC1G3157DCKR chip U9, and the 6 pin of U9 is connected to the 47 pin of U7.
电阻R27另一端与SN74LVC1G3157DCKR芯片U10的1脚相连，U10的6脚与U7的46脚相连。The other end of resistor R27 is connected to
电阻R31另一端与SN74LVC1G3157DCKR芯片U11的1脚相连，U11的6脚与U7的45脚相连。The other end of resistor R31 is connected to
电阻R33另一端与SN74LVC1G3157DCKR芯片U12的1脚相连，U12的6脚与U7的44脚相连。The other end of resistor R33 is connected to
UA2的1脚分别与电阻R17一端、电容C23一端、电阻R29一端相连，电阻R29另一端分别与UA2的2脚、电阻R32一端相连，电阻R32另一端接2.5V，阻R17另一端分别与UA8的3脚、电容C33一端相连；电容C23另一端通过电阻R25分别与电阻R24一端、电容C28一端、电容C31一端、电阻R30一端、UA2的6脚相连，电阻R24另一端分别与电阻R23一端、电容C28另一端、二极管D8阴极相连，电阻R23另一端分别与电容C26一端、电阻R22一端相连，电阻R22另一端分别与电容C30一端、U1的6脚相连，电容C30另一端分别与电容C26另一端、U1的11脚、电容C31另一端、电阻R30另一端、二极管D9阳极相连，二极管D9阴极分别与二极管D8阳极、UA2的7脚相连，UA2的5脚接2.5V电压并通过电容C147接AGND。
电压互感器一次线圈另一端和电压互感器二次线圈另一端接AGND。The other end of the primary coil of the voltage transformer and the other end of the secondary coil of the voltage transformer are connected to AGND.
UA7的2脚接2.7V电压并通过电容C130分别与AGND、电容C29一端相连，电容C29另一端接AVCC5V电源，UA7的1脚分别与U21的97脚、U7的97脚相连；电容C21通过电阻R19分别与UA7的6脚、电阻R28一端相连，电阻R28另一端分别与UA7的7脚、电阻R18一端相连，电阻R18另一端分别与U21的31脚、电容C22一端相连，电容C22另一端接AGND；UA7的5脚接1.5V电压。
UA8的2脚接2.7V电压并通过电容C152分别与AGND、电容C43一端相连，电容C43另一端接AVCC5V电源，UA8的1脚分别与U21的98脚、U7的98脚相连；电容C33通过电阻R36分别与UA8的6脚、电阻R38一端相连，电阻R38另一端分别与UA8的7脚、电阻R37一端相连，电阻R37另一端分别与U21的32脚、电容C34一端相连，电容C34另一端接AGND；UA8的5脚接1.5V电压。
U1的1脚接U7的71脚，U1的2脚分别与晶振Y1一端、电容C11一端相连，电容C11另一端通过电容C12分别与晶振Y1另一端U1的3脚相连，U1的4脚接U7的70脚，U1的5脚接U7的29脚，U1的6脚接U7的29脚，U1的14脚接U7的68脚，U1的13脚接U7的67脚，U1的12脚接U7的66脚，U1的10脚分别与电阻R134一端、电容C1一端、电容C2一端、电容C3一端、电容C4一端相连，电阻R134另一端分别与AGND、变阻器R1一端相连，变阻器R1另一端接AVCC5V电源相连，变阻器R1调节端分别与电容C1另一端、电容C2另一端、电容C3另一端、电容C4另一端、U1的9脚相连。
U7的26脚与U21的78脚相连，U7的25脚与U21的79脚相连。Pin 26 of U7 is connected to
另外，本发明所述稳压电路包括REF02芯片U30、LM358芯片UA13、KA34063A芯片U31和PAM2312芯片U32，U30的2脚通过电阻R110接电池，U30的6脚分别与电阻R111一端、电阻R119一端相连，电阻R119另一端分别与电阻R122一端、UA13的5脚相连，电阻R122另一端分别与AGND、U30的4脚相连，UA13的7脚分别与UA13的6脚、电阻R125一端相连，电阻R125另一端通过电容C127接地；电阻R125另一端为2.5V电压端；电阻R111另一端接UA13的3脚，UA13的1脚通过电阻R114接NPN三极管Q1的基极，三极管Q1的集电极接U30的2脚，三极管Q1的发射极为VCC5V电源端并分别与UA13的2脚、电阻R112一端、可变电阻R115一端、电阻R113一端相连，电阻R112另一端为1.5V电压端并分别与电阻R117一端、电容C119一端相连，电阻R117另一端、电容C119另一端接地；可变电阻R115调节端为2.7V电压端并通过电容C120接地，可变电阻R115另一端接地；电阻R113另一端为3V电压端并分别与电阻R118一端、电容C121一端相连，电阻R118另一端、电容C121另一端接地。In addition, the voltage regulator circuit of the present invention includes REF02 chip U30, LM358 chip UA13, KA34063A chip U31 and PAM2312 chip U32.
U31的1脚分别与二极管D27阳极、电感L2一端相连，二极管D27阴极分别与电阻R121一端、电池相连，电阻R121另一端分别与电阻R126一端、U31的5脚相连，电阻R126另一端接地，电感L2另一端分别与电阻R120一端、电阻R123一端、U31的6脚、VCC5V电源端相连，电阻R120另一端接U31的8脚，电阻R123另一端接U31的7脚。
U32的1脚通过电阻R127接VCC5电源端，U32的2脚通过电阻R130分别与电阻R131、U32的5脚相连，电阻R131另一端分别与电感L4一端、电感L5一端相连，电感L4另一端接U32的3脚，电感L5另一端为VCC3.3电源端；U32的4脚接VCC5电源端。
本发明有益效果。The present invention has beneficial effects.
本发明将试验仪和测量表计综合在一起，生产出一个轻便试验仪、能够一次性完成CT变比、极性的测试。The invention integrates the tester and the measuring meter to produce a portable tester, which can complete the CT transformation ratio and polarity tests at one time.
本发明测试仪具备波形显示功能、及正弦波有效值测试功能，且对大小电压均具有高精度的测试效果。The tester of the invention has a waveform display function and a sine wave effective value test function, and has a high-precision test effect for both large and small voltages.
本发明改用变压比的方式进行变比测试；用波形显示功能进行极性测试。并将两步测试合并成一步测试；将测试仪与测试表计合二为一，成为一个综合测试仪。The present invention uses the transformation ratio method to carry out the transformation ratio test, and uses the waveform display function to carry out the polarity test. The two-step test is combined into one-step test; the tester and the test meter are combined into one, becoming a comprehensive tester.
和传统的、目前广泛使用的互感器变比极性测试方法不同，本发明专利利用带波形显示功能的电流互感器、电压互感器变比、极性测试仪将变比、极性测试的两项工作合并为一项来完成。Different from the traditional and currently widely used transformer ratio and polarity testing methods, the patent of the present invention uses the current transformer with waveform display function, the voltage transformer ratio, and the polarity tester to test the ratio and polarity. The work is combined into one to complete.
本发明利用加小电压对大变比的电压互感器进行变比、极性的校验。In the invention, the voltage transformer with large transformation ratio is used to check the transformation ratio and polarity by applying a small voltage.
本发明可用电压比的方法代替电流比的方法对电流互感器进行变比校验，利用波形显示、比较的方法进行电流互感器极性校验。The invention can use the method of voltage ratio instead of the method of current ratio to check the transformation ratio of the current transformer, and use the method of waveform display and comparison to check the polarity of the current transformer.
附图说明Description of drawings
下面结合附图和具体实施方式对本发明做进一步说明。本发明保护范围不仅局限于以下内容的表述。The present invention will be further described below with reference to the accompanying drawings and specific embodiments. The protection scope of the present invention is not limited to the following descriptions.
图1电流互感器极性校验传统试验方法试验接线图。Figure 1. The test wiring diagram of the traditional test method for the polarity verification of the current transformer.
图2互感器A与C为同极性端时，一二次线圈的电压波形。Figure 2 When the transformers A and C are the same polarity terminals, the voltage waveform of the primary and secondary coils.
图3互感器A与C为反极性端时，一二次线圈的电压波形。Figure 3 When the transformers A and C are opposite polarity terminals, the voltage waveform of the primary and secondary coils.
图4是本发明结构框图。Figure 4 is a structural block diagram of the present invention.
图5是本发明交流输入部分电路和整流滤波电路原理图。FIG. 5 is a schematic diagram of the AC input circuit and the rectifier filter circuit of the present invention.
图6是本发明波形输出及相位检测电路图。Fig. 6 is the circuit diagram of waveform output and phase detection of the present invention.
图7是图5中整流滤波电路图。FIG. 7 is a diagram of the rectifier filter circuit in FIG. 5 .
图8、图9是本发明模数转换电路图。8 and 9 are the analog-to-digital conversion circuit diagrams of the present invention.
图10是本发明主控部分电路原理图。Fig. 10 is a circuit schematic diagram of the main control part of the present invention.
图11-14是图10由上至下分解放大图。11-14 are exploded and enlarged views of FIG. 10 from top to bottom.
图15-17是本发明稳压电路原理图。15-17 are schematic diagrams of the voltage stabilizing circuit of the present invention.
图18是图5中交流输入部分电路原理图。FIG. 18 is a circuit schematic diagram of the AC input part in FIG. 5 .
具体实施方式Detailed ways
如图所示，本发明包括逆变器、电池、电压调节器和带有波形显示功能的能够测量电压互感器一次加入电压有效值及电压互感器二次电压输出值的测量表计，逆变器的电源输入端与电池相连，逆变器的电源输出端与电压调节器的电源输入端相连，电压调节器的电源输出端与电压互感器一次线圈相连，电压互感器一次线圈与测量表计一次线圈测量端相连，电压互感器二次线圈与测量表计二次线圈测量端相连，测量表计电源端与电池相连。As shown in the figure, the present invention includes an inverter, a battery, a voltage regulator and a measuring meter with a waveform display function capable of measuring the effective value of the primary voltage added to the voltage transformer and the secondary voltage output value of the voltage transformer. The power input terminal of the inverter is connected to the battery, the power output terminal of the inverter is connected to the power input terminal of the voltage regulator, the power output terminal of the voltage regulator is connected to the primary coil of the voltage transformer, and the primary coil of the voltage transformer is connected to the measuring meter. The measuring end of the primary coil is connected, the secondary coil of the voltage transformer is connected with the measuring end of the secondary coil of the measuring meter, and the power supply end of the measuring meter is connected with the battery.
测量表计包括交流输入部分、波形输出及相位检测电路、整流滤波电路、模数转换电路、主控部分、稳压电路和显示屏幕，交流输入部分的输入端口分别与测量表计一次线圈测量端、测量表计二次线圈测量端、增益切换控制部分输出端口相连，交流输入部分的输出端口分别与整流滤波电路的输入端口、波形输出及相位检测电路的输入端口相连，整流滤波电路的输出端口与模数转换电路的输入端口相连。The measuring meter includes an AC input part, a waveform output and phase detection circuit, a rectifier filter circuit, an analog-to-digital conversion circuit, a main control part, a voltage regulator circuit and a display screen. , The measurement terminal of the secondary coil of the measuring meter is connected to the output port of the gain switching control part, the output port of the AC input part is connected to the input port of the rectifier filter circuit, the waveform output and the input port of the phase detection circuit respectively, and the output port of the rectifier filter circuit is connected. Connect with the input port of the analog-to-digital conversion circuit.
主控部分分别与增益切换控制部分的输入端口、波形输出及相位检测电路的输出端口、模数转换电路的输出端口、显示屏幕、稳压电路相连。The main control part is respectively connected with the input port of the gain switching control part, the output port of the waveform output and the phase detection circuit, the output port of the analog-digital conversion circuit, the display screen and the voltage regulator circuit.
所述逆变器为功率500W或1000W、输入为直流12伏、输出为交流220伏正弦波的逆变器，电池为12伏、20-100安时的锂离子电池或铅酸免维护电池，电压调节器为输入220交流、输出0-250伏的电压功率500W的电压调整器。The inverter is an inverter with a power of 500W or 1000W, the input is DC 12V, and the output is AC 220V sine wave, and the battery is a 12V, 20-100Ah lithium-ion battery or lead-acid maintenance-free battery, The voltage regulator is a voltage regulator with an input of 220 AC and an output voltage of 0-250 volts and a power of 500W.
所述主控部分包括STM32F103VDT6芯片U7和STM32F103VDT6芯片U21。The main control part includes STM32F103VDT6 chip U7 and STM32F103VDT6 chip U21.
波形输出及相位检测电路包括opa2333芯片UA7和opa2333芯片UA8。The waveform output and phase detection circuit includes opa2333 chip UA7 and opa2333 chip UA8.
模数转换电路包括ad7705芯片U1。The analog-to-digital conversion circuit includes the ad7705 chip U1.
交流输入部分包括opa2333芯片UA1和opa2333芯片UA2，UA1的3脚分别与二极管D1阳极、二极管D2阴极、电阻R4一端、电阻R9一端、电阻R11一端、电阻R14一端、电阻R16一端相连，电阻R4另一端依次通过电阻R5、电容C5与电压互感器一次线圈一端（图4中电压互感器的A端）相连，二极管D1阴极接AVCC5V端，二极管D2阳极接AGND端；电阻R9另一端与SN74LVC1G3157DCKR芯片U2的1脚相连，U2的6脚与U7的53脚相连。The AC input part includes opa2333 chip UA1 and opa2333 chip UA2. The 3 pins of UA1 are respectively connected to the anode of diode D1, the cathode of diode D2, one end of resistor R4, one end of resistor R9, one end of resistor R11, one end of resistor R14, one end of resistor R16, and the other end of resistor R4. One end is connected to one end of the primary coil of the voltage transformer (the A terminal of the voltage transformer in Figure 4) through the resistor R5 and the capacitor C5 in turn, the cathode of the diode D1 is connected to the AVCC5V terminal, and the anode of the diode D2 is connected to the AGND terminal; the other end of the resistor R9 is connected to the SN74LVC1G3157DCKR
电阻R11另一端与SN74LVC1G3157DCKR芯片U3的1脚相连，U3的6脚与U7的52脚相连。The other end of resistor R11 is connected to pin 1 of U3 of SN74LVC1G3157DCKR chip, and
电阻R14另一端与SN74LVC1G3157DCKR芯片U4的1脚相连，U4的6脚与U7的51脚相连。The other end of resistor R14 is connected to pin 1 of U4 of SN74LVC1G3157DCKR chip, and
电阻R16另一端与SN74LVC1G3157DCKR芯片U6的1脚相连，U6的6脚与U7的48脚相连。The other end of resistor R16 is connected to pin 1 of U6 of SN74LVC1G3157DCKR chip, and
UA1的1脚分别与电阻R2一端、电容C6一端、电阻R12一端相连，电阻R12另一端分别与UA1的2脚、电阻R15一端相连，电阻R15另一端接2.5V，阻R2另一端分别与UA7的3脚、电容C21一端相连；电容C6另一端通过R8分别与电阻R7一端、电容C8一端、电容C10一端、电阻R13一端、UA1的6脚相连，电阻R7另一端分别与电阻R6一端、电容C8另一端、二极管D4阴极相连，电阻R6另一端分别与电容C7一端、电阻R3一端相连，电阻R3另一端分别与电容C9一端、U1的7脚相连，电容C9另一端分别与电容C7另一端、U1的8脚、电容C10另一端、电阻R13另一端、二极管D5阳极相连，二极管D5阴极分别与二极管D4阳极、UA1的7脚相连，UA1的5脚接2.5V电压并通过电容C146接AGND。
UA2的3脚分别与二极管D6阳极、二极管D7阴极、电阻R20一端、电阻R26一端、电阻R27一端、电阻R31一端、电阻R33一端相连，电阻R20另一端依次通过电阻R21、电容C24与电压互感器二次线圈一端（图4中电压互感器的B端）相连，二极管D6阴极接AVCC5V端，二极管D7阳极接AGND端；电阻R26另一端与SN74LVC1G3157DCKR芯片U9的1脚相连，U9的6脚与U7的47脚相连。The 3 pins of UA2 are respectively connected with the anode of diode D6, the cathode of diode D7, one end of resistor R20, one end of resistor R26, one end of resistor R27, one end of resistor R31 and one end of resistor R33, and the other end of resistor R20 is connected to the voltage transformer through resistor R21 and capacitor C24 in turn. One end of the secondary coil (the B end of the voltage transformer in Figure 4) is connected, the cathode of the diode D6 is connected to the AVCC5V end, the anode of the diode D7 is connected to the AGND end; the other end of the resistor R26 is connected to the 1 pin of the SN74LVC1G3157DCKR chip U9, and the 6 pin of U9 is connected to the U7 47 pins are connected.
电阻R27另一端与SN74LVC1G3157DCKR芯片U10的1脚相连，U10的6脚与U7的46脚相连。The other end of resistor R27 is connected to pin 1 of U10 of SN74LVC1G3157DCKR chip, and
电阻R31另一端与SN74LVC1G3157DCKR芯片U11的1脚相连，U11的6脚与U7的45脚相连。The other end of resistor R31 is connected to pin 1 of U11 of SN74LVC1G3157DCKR chip, and
电阻R33另一端与SN74LVC1G3157DCKR芯片U12的1脚相连，U12的6脚与U7的44脚相连。The other end of resistor R33 is connected to pin 1 of U12 of the SN74LVC1G3157DCKR chip, and
UA2的1脚分别与电阻R17一端、电容C23一端、电阻R29一端相连，电阻R29另一端分别与UA2的2脚、电阻R32一端相连，电阻R32另一端接2.5V，阻R17另一端分别与UA8的3脚、电容C33一端相连；电容C23另一端通过电阻R25分别与电阻R24一端、电容C28一端、电容C31一端、电阻R30一端、UA2的6脚相连，电阻R24另一端分别与电阻R23一端、电容C28另一端、二极管D8阴极相连，电阻R23另一端分别与电容C26一端、电阻R22一端相连，电阻R22另一端分别与电容C30一端、U1的6脚相连，电容C30另一端分别与电容C26另一端、U1的11脚、电容C31另一端、电阻R30另一端、二极管D9阳极相连，二极管D9阴极分别与二极管D8阳极、UA2的7脚相连，UA2的5脚接2.5V电压并通过电容C147接AGND。
电压互感器一次线圈另一端和电压互感器二次线圈另一端接AGND。The other end of the primary coil of the voltage transformer and the other end of the secondary coil of the voltage transformer are connected to AGND.
UA7的2脚接2.7V电压并通过电容C130分别与AGND、电容C29一端相连，电容C29另一端接AVCC5V电源，UA7的1脚分别与U21的97脚、U7的97脚相连；电容C21通过电阻R19分别与UA7的6脚、电阻R28一端相连，电阻R28另一端分别与UA7的7脚、电阻R18一端相连，电阻R18另一端分别与U21的31脚、电容C22一端相连，电容C22另一端接AGND；UA7的5脚接1.5V电压。
UA8的2脚接2.7V电压并通过电容C152分别与AGND、电容C43一端相连，电容C43另一端接AVCC5V电源，UA8的1脚分别与U21的98脚、U7的98脚相连；电容C33通过电阻R36分别与UA8的6脚、电阻R38一端相连，电阻R38另一端分别与UA8的7脚、电阻R37一端相连，电阻R37另一端分别与U21的32脚、电容C34一端相连，电容C34另一端接AGND；UA8的5脚接1.5V电压。
U1的1脚接U7的71脚，U1的2脚分别与晶振Y1一端、电容C11一端相连，电容C11另一端通过电容C12分别与晶振Y1另一端U1的3脚相连，U1的4脚接U7的70脚，U1的5脚接U7的29脚，U1的6脚接U7的29脚，U1的14脚接U7的68脚，U1的13脚接U7的67脚，U1的12脚接U7的66脚，U1的10脚分别与电阻R134一端、电容C1一端、电容C2一端、电容C3一端、电容C4一端相连，电阻R134另一端分别与AGND、变阻器R1一端相连，变阻器R1另一端接AVCC5V电源相连，变阻器R1调节端分别与电容C1另一端、电容C2另一端、电容C3另一端、电容C4另一端、U1的9脚相连。
U7的26脚与U21的78脚相连，U7的25脚与U21的79脚相连。Pin 26 of U7 is connected to pin 78 of U21, and pin 25 of U7 is connected to pin 79 of U21.
本发明电压采集是通过整流滤波之后经过高精度ad采集，既有波形显示，同时兼有万用表的精度。The voltage acquisition in the present invention is collected by high-precision ad after rectification and filtering, and has both waveform display and the precision of a multimeter.
所述稳压电路包括REF02芯片U30、LM358芯片UA13、KA34063A芯片U31和PAM2312芯片U32，U30的2脚通过电阻R110接电池，U30的6脚分别与电阻R111一端、电阻R119一端相连，电阻R119另一端分别与电阻R122一端、UA13的5脚相连，电阻R122另一端分别与AGND、U30的4脚相连，UA13的7脚分别与UA13的6脚、电阻R125一端相连，电阻R125另一端通过电容C127接地；电阻R125另一端为2.5V电压端；电阻R111另一端接UA13的3脚，UA13的1脚通过电阻R114接NPN三极管Q1的基极，三极管Q1的集电极接U30的2脚，三极管Q1的发射极为VCC5V电源端并分别与UA13的2脚、电阻R112一端、可变电阻R115一端、电阻R113一端相连，电阻R112另一端为1.5V电压端并分别与电阻R117一端、电容C119一端相连，电阻R117另一端、电容C119另一端接地；可变电阻R115调节端为2.7V电压端并通过电容C120接地，可变电阻R115另一端接地；电阻R113另一端为3V电压端并分别与电阻R118一端、电容C121一端相连，电阻R118另一端、电容C121另一端接地。The voltage regulator circuit includes REF02 chip U30, LM358 chip UA13, KA34063A chip U31 and PAM2312 chip U32.
U31的1脚分别与二极管D27阳极、电感L2一端相连，二极管D27阴极分别与电阻R121一端、电池相连，电阻R121另一端分别与电阻R126一端、U31的5脚相连，电阻R126另一端接地，电感L2另一端分别与电阻R120一端、电阻R123一端、U31的6脚、VCC5V电源端相连，电阻R120另一端接U31的8脚，电阻R123另一端接U31的7脚。
U32的1脚通过电阻R127接VCC5电源端，U32的2脚通过电阻R130分别与电阻R131、U32的5脚相连，电阻R131另一端分别与电感L4一端、电感L5一端相连，电感L4另一端接U32的3脚，电感L5另一端为VCC3.3电源端；U32的4脚接VCC5电源端。
图18的交流输入部分，采用电阻分压方式实现电压增益自动控制，输入电压分成0-200mV、200mV-2V、2V-20V、20V-200V、200V-500V五个档位。D1、D2防止超压损坏运算放大器。高精密运放实现以2.5V为中心线的最大波峰不超过5V的正弦波输出。档位调整是通过处理器控制R9,R11,R14,R16，分别接2.5v实现的输入信号对2.5v分压产生5个挡位。In the AC input part of Figure 18, the voltage gain automatic control is realized by the resistance voltage division method, and the input voltage is divided into five gears: 0-200mV, 200mV-2V, 2V-20V, 20V-200V, and 200V-500V. D1 and D2 prevent overvoltage from damaging the operational amplifier. The high-precision op amp realizes a sine wave output with a maximum peak value of no more than 5V with 2.5V as the center line. Gear adjustment is to control R9, R11, R14, R16 through the processor, and connect the input signal realized by 2.5v to generate 5 gears for the partial pressure of 2.5v.
如图6为正弦波整形输出电路和相位检测电路，波形通过C21输入到压限运放UA7B中，输出以1.5V为中心0-3V区间波动的正弦波输出到中央处理器内部高速ADC。UA7A运放工作在比较器模式下，当电压大于2.7V输出时，运放输出高电平触发处理器实现相位检测。INT1、INT2为过零触发端。Figure 6 shows the sine wave shaping output circuit and phase detection circuit. The waveform is input to the voltage-limiting op amp UA7B through C21, and the output sine wave fluctuating in the 0-3V interval with 1.5V as the center is output to the high-speed ADC inside the central processing unit. The UA7A op amp works in comparator mode. When the output voltage is greater than 2.7V, the op amp outputs a high level to trigger the processor to achieve phase detection. INT1 and INT2 are zero-cross trigger terminals.
如图7，高精度电压采集电路采用差分电压输出（V1+、V1-）形式，波形通过C6输入到UA1B中进行平均值整流滤波。As shown in Figure 7, the high-precision voltage acquisition circuit adopts the form of differential voltage output (V1+, V1-), and the waveform is input to UA1B through C6 for average rectification and filtering.
如图8，高精度模数转换电路采用16位AD7705转换芯片实现高精度电压采集，电压采集精度4位半。As shown in Figure 8, the high-precision analog-to-digital conversion circuit uses a 16-bit AD7705 conversion chip to achieve high-precision voltage acquisition, and the voltage acquisition accuracy is 4 and a half digits.
本发明利用锂离子电池提供的12伏直流，接入到逆变器的A/B输入端，经过逆变器的转换，从C/D端输出频率为50HZ的交流正弦波电源。该电源作为电压互感器变比、极性测试用的工作电源，以代替普通的墙壁电源，电源与试验仪表一体化设计，省力的同时减少试验接线的数量级重量。The invention utilizes the 12-volt direct current provided by the lithium ion battery, which is connected to the A/B input end of the inverter, and after the inverter is converted, the AC sine wave power supply with a frequency of 50HZ is output from the C/D end. The power supply is used as a working power supply for voltage transformer ratio and polarity testing to replace ordinary wall power supplies. The integrated design of power supply and test instrument saves effort and reduces the weight of test wiring.
本发明将逆变器产生的50HZ交流正弦波电源，接入电压调整器的输入端A/B，通过电压调整器内部的空开K及隔离变压器，经端子C/D输出0-250伏的测试电压互感器变比极性所需的工作电压。In the present invention, the 50HZ AC sine wave power supply generated by the inverter is connected to the input terminal A/B of the voltage regulator, through the air switch K and the isolation transformer inside the voltage regulator, and outputs 0-250V through the terminal C/D. The working voltage required to test the ratio polarity of the voltage transformer.
再将上述电压调整器输出的C/D电压同时加入到电压互感器的一次线圈A/B及带波形显示功能的测试表计的A/B端；另外再把电压互感器（或电流互感器）二次线圈端子C/D接入带波形显示功能的测量表计的C/D端。Then add the C/D voltage output by the above voltage regulator to the primary coil A/B of the voltage transformer and the A/B terminal of the test meter with the waveform display function at the same time; ) The secondary coil terminal C/D is connected to the C/D terminal of the measuring meter with the waveform display function.
测量表计的A/B端读取的交流电压U1及C/D端电压U2之比U2/U1即为变比大小。The ratio U2/U1 of the AC voltage U1 and the C/D terminal voltage U2 read by the A/B terminal of the measuring meter is the transformation ratio.
显示出的U1电压波形如果与U2电压波形相同,如图2，则电压互感器或电流互感器的A与C端子为同极性端(同时B与D为同极性端）。If the displayed U1 voltage waveform is the same as the U2 voltage waveform, as shown in Figure 2, the A and C terminals of the voltage transformer or current transformer are the same polarity terminals (and B and D are the same polarity terminals).
显示出的U1电压波形如果U1与U2电压波形相反，如图3，则电压互感器或电流互感器的A与C端子为反极性端(同时B与D为反极性端）。The displayed U1 voltage waveform If the U1 and U2 voltage waveforms are opposite, as shown in Figure 3, then the A and C terminals of the voltage transformer or current transformer are opposite polarity terminals (and B and D are opposite polarity terminals).
如此便一次性完成了互感器变比与极性的测试。In this way, the transformer ratio and polarity tests are completed at one time.
可以理解的是，以上关于本发明的具体描述，仅用于说明本发明而并非受限于本发明实施例所描述的技术方案，本领域的普通技术人员应当理解，仍然可以对本发明进行修改或等同替换，以达到相同的技术效果；只要满足使用需要，都在本发明的保护范围之内。It can be understood that the above specific description of the present invention is only used to illustrate the present invention and is not limited to the technical solutions described in the embodiments of the present invention. Those of ordinary skill in the art should understand that the present invention can still be modified or It is equivalent to replacement to achieve the same technical effect; as long as it meets the needs of use, it is within the protection scope of the present invention.
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| CN110261726A (en) * | 2019-07-25 | 2019-09-20 | 国网河北省电力有限公司邢台供电分公司 | A discharge coil polarity testing device |
| CN110988572A (en) * | 2019-12-27 | 2020-04-10 | 焦洋 | Voltage generator |
| CN112526412A (en) * | 2020-11-17 | 2021-03-19 | 国网湖南省电力有限公司 | Method and system for testing polarity of current transformer of transformer lifting seat |
| CN114137469A (en) * | 2021-11-25 | 2022-03-04 | 国网陕西省电力公司西咸新区供电公司 | Method and system for realizing intelligent calibration of multi-tap current transformer |
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