CN114089009A - Inrush current suppression type voltage transformer based on current sensitive resistor technology - Google Patents
Inrush current suppression type voltage transformer based on current sensitive resistor technology Download PDFInfo
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- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
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Abstract
The invention discloses an inrush current suppression type voltage transformer based on a current sensitive resistor technology, and belongs to the technical field of voltage transformers. The device comprises a device body, wherein the device body comprises a fixed base and a closed installation shell, the closed installation shell is fixedly connected to the fixed base, and a first high-voltage winding, a second high-voltage winding and a third high-voltage winding are fixedly installed inside the closed installation shell; secondary winding voltage transformers are fixedly arranged on the first high-voltage winding, the second high-voltage winding and the third high-voltage winding, the first high-voltage winding, the second high-voltage winding and the third high-voltage winding respectively form corresponding voltage mutual induction units together with the corresponding secondary winding voltage transformers, and a flow-sensitive resonance elimination mechanism is arranged between the adjacent voltage mutual induction units; the invention effectively solves the problems that the PT high-voltage fuse is easy to be frequently fused and the body is easily burnt in the use process of the voltage transformer, and the inrush current of the voltage transformer cannot be effectively inhibited.
Description
Technical Field
The invention relates to the technical field of voltage transformers, in particular to an inrush current suppression type voltage transformer based on a current sensitive resistor technology.
Background
The flow-sensitive resistor is actually called as PTC thermistor, and is a material with positive temperature coefficient characteristic, and is an oxide ceramic element with main components; the voltage transformer is an important device for measurement and protection in a power system, and mainly has the function of providing information for a measuring instrument, an instrument or a relay protection and control device; isolating the measurement, protection and control devices from the high voltage plays an important role in power systems. The electromagnetic voltage transformer is a voltage transformer which converts a primary voltage into a secondary voltage in proportion by electromagnetic induction. The magnetic field generating device is manufactured by utilizing the electromagnetic induction principle and has the characteristics of small capacity and long-term stable operation.
The neutral point of a common voltage transformer on the market is usually directly grounded, and the saturated resonance theory shows that the iron core inductance is saturated due to the increase of current or the increase of voltage due to the nonlinear relation between the magnetic flux and the current of the iron core inductance of the transformer, so that the voltage transformer is easy to generate ferromagnetic resonance.
Disclosure of Invention
The invention aims to solve the following problems in the prior art:
the problems of frequent fusing of PT high-voltage fuse and body burnout of the voltage transformer easily occur in the use process, and the problem of inrush current of the voltage transformer cannot be solved in the existing design.
In order to achieve the purpose, the invention adopts the following technical scheme:
an inrush current suppression type voltage transformer based on a current-sensitive resistor technology comprises a device body, wherein the device body comprises a fixed base and a closed installation shell, the closed installation shell is fixedly connected to the fixed base, a first high-voltage winding, a second high-voltage winding and a third high-voltage winding are fixedly installed inside the closed installation shell, the tail ends of the first high-voltage winding, the second high-voltage winding and the third high-voltage winding are mutually short-circuited, and the head ends of the first high-voltage winding, the second high-voltage winding and the third high-voltage winding respectively correspond to the three ends of external three-phase electricity; secondary winding voltage transformers are fixedly mounted on the first high-voltage winding, the second high-voltage winding and the third high-voltage winding, the first high-voltage winding, the second high-voltage winding and the third high-voltage winding respectively form corresponding voltage mutual induction units with the corresponding secondary winding voltage transformers, and a flow-sensitive resonance elimination mechanism is mounted between every two adjacent voltage mutual induction units.
Preferably, the current-sensitive harmonic elimination mechanism comprises a conductive groove and a current-sensitive primary harmonic eliminator, the conductive groove is a metal flange groove, the conductive groove is fixedly connected to the outer side wall of the closed installation shell between the voltage mutual induction units, the current-sensitive primary harmonic eliminator is also connected with a connecting mechanism, and the current-sensitive primary harmonic eliminator is inserted in the conductive groove through the connecting mechanism; and a binding post is fixedly connected to the side wall of the flow-sensitive primary resonance eliminator.
Preferably, the connecting mechanism comprises a conductive column, the conductive column is fixedly connected to the bottom end of the flow-sensitive primary resonance eliminator, a metal connecting lug is fixedly connected to the side wall of the conductive column, a columnar bump is fixedly connected to the edge of the metal connecting lug close to the outer side, and metal elastic sheets are fixedly connected to the upper surface and the lower surface of the metal connecting lug; one end of the current-sensitive primary harmonic eliminator is horizontally inserted and connected onto the conductive groove through a connecting mechanism and is connected with a neutral point of an adjacent high-voltage winding in series, and the other end of the current-sensitive primary harmonic eliminator is grounded.
Preferably, a temperature sensor and a current sensor are integrally installed inside the secondary winding voltage transformer, a temperature signal uploading interface is fixedly connected to the temperature sensor and used for measuring the operating temperature of the voltage transformer in real time, and a current signal uploading interface is fixedly connected to the current sensor and used for collecting current flowing on the current-sensitive primary resonance eliminator.
Preferably, the method further comprises a performance test method of the inrush current suppression type voltage transformer, and specifically comprises the following steps:
s1, designing a contrast experiment, namely taking a common voltage transformer as a contrast group of the experiment, taking the device body as an experiment group, and connecting the common voltage transformer and the device body into the same experiment circuit;
s2, directly grounding neutral points of the control group and the experimental group, performing a simulation experiment, connecting a circuit, and collecting three-phase voltages of the overvoltage transformers flowing in the control group and the experimental group and current between the neutral points and the ground by using an oscilloscope;
s3, arranging the voltage and current data of the control group and the experimental group acquired in the S2, and carrying out graph acquisition on the data through an oscilloscope;
and S4, processing and analyzing the data obtained in the S3, and verifying the capability of the device body and the common voltage transformer for inhibiting the primary neutral point inrush current of the voltage transformer.
Preferably, the step of connecting the device body to the experimental circuit in S1 specifically includes the following steps:
a1, testing the flow-sensitive primary harmonic eliminator of the flow-sensitive harmonic elimination mechanism, and testing the insulation resistance of the flow-sensitive primary harmonic eliminator by using a 1000V megger;
a2, judging whether the current-sensitive primary harmonic eliminator is normal or not according to the insulation resistance value measured by A1, if the insulation resistance value is 40-210 k omega, the current-sensitive primary harmonic eliminator is normal, installing the current-sensitive primary harmonic eliminator into a conductive groove on the outer side wall of a closed installation shell of the device body through a connecting mechanism at the bottom end of the current-sensitive primary harmonic eliminator, and otherwise, replacing a current-sensitive primary harmonic eliminator element and repeating the operation of A1;
a3, after the operation of A2 is completed, the bottom end of the current-sensitive primary harmonic eliminator is grounded, and meanwhile, the current-sensitive primary harmonic eliminator is connected into an experimental circuit in series through a lead and a binding post at the other end of the current-sensitive primary harmonic eliminator, wherein the first high-voltage winding, the second high-voltage winding and the third high-voltage winding are connected with a three-phase circuit of the experimental circuit, and the head ends of the first high-voltage winding, the second high-voltage winding and the third high-voltage winding respectively correspond to three ends of three-phase electricity; and the tail ends of the first high-voltage winding, the second high-voltage winding and the third high-voltage winding are connected with a grounding circuit of the experimental circuit in series.
Preferably, the method further comprises the step of connecting the device body into an experimental circuit under the condition that the flow-sensitive type primary resonance eliminator is not installed, taking the device body as a new experimental group, and repeating the operations from S2 to S4 to verify the anti-resonance performance of the device body.
Compared with the prior art, the invention provides an inrush current suppression type voltage transformer based on a current sensitive resistor technology, which has the following beneficial effects:
(1) the high-voltage winding and the secondary winding voltage transformer form a voltage mutual inductance unit, a conductive groove is fixedly connected on the outer side wall of a closed installation shell between adjacent voltage mutual inductance units, a current-sensitive resonance elimination mechanism is also inserted on the conductive groove and is installed between the neutral point of the secondary winding voltage transformer and the ground, when the secondary winding voltage transformer resonates, zero-sequence voltage rises, current flows through the current-sensitive resonance elimination mechanism, under the normal operation state, the current-sensitive resonance elimination mechanism is in a low resistance state, the zero-sequence loop of the secondary winding voltage transformer is not changed, the measurement precision of the secondary winding voltage transformer is not influenced, the unbalanced voltage of the neutral point is not amplified, when the voltage transformer generates inrush current or resonance, the resistance tends to infinity, which is equivalent to the grounding of the transformer, the zero-sequence resonance loop is destroyed, and the resonance problems of frequent fusing of the high-voltage transformer, burning of a body and the like can be effectively solved; one end of a current sensitive primary harmonic eliminator of the current sensitive harmonic elimination mechanism is horizontally inserted and connected onto the conductive groove through a connecting mechanism, a columnar bulge is fixedly connected onto the side wall of the connecting mechanism, the connecting structure is conveniently inserted into the conductive groove, and meanwhile, a metal elastic sheet is fixedly connected onto the metal connecting lug, so that the stability of connection between the current sensitive primary harmonic eliminator and the conductive groove can be better ensured on the basis of ensuring the convenience of installation and connection; furthermore, the flow-sensitive primary harmonic eliminator is horizontally installed, so that the space is greatly saved, and the total volume of the harmonic eliminating voltage transformer is smaller than that of the conventional design.
(2) The invention also provides a performance test method of the inrush current suppression type voltage transformer based on the current-sensitive resistance technology, and the suppression effect of the inrush current suppression type voltage transformer based on the current-sensitive resistance technology on the resonance problem of the voltage transformer during working is effectively verified through a design comparison experiment; when the voltage transformer generates inrush current or ferromagnetic resonance, the resistance of the current-sensitive primary resonance eliminator can be suddenly increased in a short time, the inrush current is quickly inhibited, resonance parameters are destroyed, and accordingly continuous and quick resonance elimination can be realized; under overvoltage, the current-sensitive primary resonance eliminator can effectively control the exciting current of the secondary winding voltage transformer below a threshold value, and normal work of a circuit is guaranteed.
Drawings
Fig. 1 is a schematic structural diagram of an inrush current suppression type voltage transformer based on a current-sensitive resistor technology according to the present invention;
fig. 2 is a schematic structural diagram of a connection mechanism of an inrush current suppression type voltage transformer based on a current-sensitive resistor technology according to the present invention;
fig. 3 is an experimental wiring schematic diagram in embodiment 2 of an inrush current suppression type voltage transformer based on a current-sensitive resistor technology according to the present invention;
fig. 4 is a schematic diagram of an inrush current suppression type voltage transformer in an embodiment 2 of the invention based on a current sensing resistor technology, wherein the diagram is acquired by a first oscilloscope in the next working condition;
fig. 5 is a schematic diagram of a second oscilloscope collected graph in the working condition of the embodiment 2 in the inrush current suppression type voltage transformer based on the current-sensitive resistor technology, which is provided by the invention;
fig. 6 is a schematic diagram of a third-time oscilloscope collection graph in an embodiment 2 of the inrush current suppression type voltage transformer based on the current-sensitive resistor technology;
fig. 7 is a schematic diagram of a graph acquired by a first oscilloscope in the working condition of example 2 in the inrush current suppression type voltage transformer based on the technology of the current sensing resistor, which is provided by the invention;
fig. 8 is a schematic diagram of a second oscilloscope acquisition graph in working condition two in embodiment 2 of an inrush current suppression type voltage transformer based on a current-sensitive resistor technology provided by the present invention;
fig. 9 is a schematic diagram of a third-time oscilloscope acquisition graph in working condition two in embodiment 2 of the inrush current suppression type voltage transformer based on the technology of the current sensing resistor.
The reference numbers in the figures illustrate:
1. a fixed base; 2. a closed mounting housing; 3. a first high voltage winding; 4. a second high voltage winding; 5. a third high voltage winding; 6. a secondary winding voltage transformer; 7. a conductive slot; 8. A flow-sensitive primary resonance eliminator; 9. a connecting mechanism; 901. a conductive post; 902. a metal connecting lug; 903. a columnar bulge; 904. a metal spring.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.
Example 1:
referring to fig. 1-2, an inrush current suppression type voltage transformer based on a current-sensitive resistor technology includes a device body, the device body includes a fixed base and a closed installation shell, the closed installation shell is fixedly connected to the fixed base, a first high-voltage winding, a second high-voltage winding and a third high-voltage winding are fixedly installed inside the closed installation shell, ends of the first high-voltage winding, the second high-voltage winding and the third high-voltage winding are in short circuit with each other, and head ends of the first high-voltage winding, the second high-voltage winding and the third high-voltage winding respectively correspond to three ends of an external three-phase current; secondary winding voltage transformers are fixedly mounted on the first high-voltage winding, the second high-voltage winding and the third high-voltage winding, the first high-voltage winding, the second high-voltage winding and the third high-voltage winding respectively form corresponding voltage mutual induction units with the corresponding secondary winding voltage transformers, and a flow-sensitive resonance elimination mechanism is mounted between every two adjacent voltage mutual induction units.
The current-sensitive harmonic elimination mechanism comprises a conductive groove and a current-sensitive primary harmonic eliminator, the conductive groove is a metal flange groove, the conductive groove is fixedly connected to the outer side wall of the closed installation shell between the voltage mutual induction units, the current-sensitive primary harmonic eliminator is also connected with a connecting mechanism, and the current-sensitive primary harmonic eliminator is inserted in the conductive groove through the connecting mechanism; and a binding post is fixedly connected to the side wall of the flow-sensitive primary resonance eliminator.
The connecting mechanism comprises a conductive column, the conductive column is fixedly connected with the bottom end of the flow-sensitive primary harmonic eliminator, a metal connecting lug is fixedly connected to the side wall of the conductive column, a columnar bulge is fixedly connected to the edge of the metal connecting lug close to the outer side, and metal elastic sheets are fixedly connected to the upper surface and the lower surface of the metal connecting lug; one end of the current-sensitive primary harmonic eliminator is horizontally inserted and connected onto the conductive groove through a connecting mechanism and is connected with a neutral point of an adjacent high-voltage winding in series, and the other end of the current-sensitive primary harmonic eliminator is grounded.
The temperature sensor and the current sensor are integrally installed in the secondary winding voltage transformer, the temperature sensor is fixedly connected with a temperature signal uploading interface and used for measuring the operating temperature of the voltage transformer in real time, and the current sensor is fixedly connected with a current signal uploading interface and used for collecting current flowing on the current-sensitive primary resonance eliminator.
The method for testing the performance of the inrush current suppression type voltage transformer comprises the following steps:
s1, designing a contrast experiment, namely taking a common voltage transformer as a contrast group of the experiment, taking the device body as an experiment group, and connecting the common voltage transformer and the device body into the same experiment circuit;
the step of connecting the device body to the experimental circuit mentioned in S1 specifically includes the steps of:
a1, testing the flow-sensitive primary harmonic eliminator of the flow-sensitive harmonic elimination mechanism, and testing the insulation resistance of the flow-sensitive primary harmonic eliminator by using a 1000V megger;
a2, judging whether the current-sensitive primary harmonic eliminator is normal or not according to the insulation resistance value measured by A1, if the insulation resistance value is 40-210 k omega, the current-sensitive primary harmonic eliminator is normal, installing the current-sensitive primary harmonic eliminator into a conductive groove on the outer side wall of a closed installation shell of the device body through a connecting mechanism at the bottom end of the current-sensitive primary harmonic eliminator, and otherwise, replacing a current-sensitive primary harmonic eliminator element and repeating the operation of A1;
a3, after the operation of A2 is completed, the bottom end of the current-sensitive primary harmonic eliminator is grounded, and meanwhile, the current-sensitive primary harmonic eliminator is connected into an experimental circuit in series through a lead and a binding post at the other end of the current-sensitive primary harmonic eliminator, wherein the first high-voltage winding, the second high-voltage winding and the third high-voltage winding are connected with a three-phase circuit of the experimental circuit, and the head ends of the first high-voltage winding, the second high-voltage winding and the third high-voltage winding respectively correspond to three ends of three-phase electricity; the tail ends of the first high-voltage winding, the second high-voltage winding and the third high-voltage winding are connected with a grounding circuit of the experimental circuit in series;
s2, directly grounding neutral points of the control group and the experimental group, carrying out a simulation experiment, switching on a circuit, and collecting three-phase voltages of the overvoltage transformers flowing in the control group and the experimental group and currents between the neutral points and the ground by using a universal meter;
s3, the voltage and current data of the control group and the experimental group acquired in the S2 are sorted, and the data are subjected to graphic acquisition through an oscilloscope;
and S4, processing and analyzing the data obtained in the S3, and verifying the capability of the device body and the common voltage transformer for inhibiting the primary neutral point inrush current of the voltage transformer.
The method also comprises the steps of connecting the device body into an experimental circuit under the condition that the flow-sensitive primary resonance eliminator is not installed, taking the device body as a new experimental group, repeating the operations from S2 to S4, and verifying the anti-resonance performance of the device body.
The high-voltage winding and a secondary winding voltage transformer 6 of the invention form a voltage mutual inductance unit, a conductive groove 7 is fixedly connected on the outer side wall of a closed installation shell 2 between adjacent voltage mutual inductance units, a current-sensitive resonance elimination mechanism is also inserted on the conductive groove 7 and is installed between the neutral point and the ground of the secondary winding voltage transformer 6, when the secondary winding voltage transformer 6 resonates, zero-sequence voltage rises, current flows through the current-sensitive resonance elimination mechanism, under the normal operation state, the current-sensitive resonance elimination mechanism is in a low resistance state, the zero-sequence loop of the secondary winding voltage transformer 6 is not changed, the measurement precision of the secondary winding voltage transformer 6 is not influenced, the neutral point unbalanced voltage is not amplified, when the voltage transformer generates inrush current or resonance, the resistance tends to infinity, which is equivalent to that the transformer is not grounded, the zero-sequence resonance loop is damaged, therefore, the resonance problems of frequent fusing of the high-voltage fuse of the voltage transformer, burning of the body and the like can be effectively solved; one end of a current-sensitive primary harmonic eliminator 8 of the current-sensitive harmonic elimination mechanism is horizontally inserted and connected onto the conductive groove 7 through a connecting mechanism 9, a columnar bulge 903 is fixedly connected onto the side wall of the connecting mechanism 9, so that the connecting structure can be conveniently inserted into the conductive groove 7, and meanwhile, a metal elastic sheet 904 is fixedly connected onto the metal connecting lug 902, so that the stability of connection between the current-sensitive primary harmonic eliminator 8 and the conductive groove 7 can be better ensured on the basis of ensuring convenient installation and connection; furthermore, the flow-sensitive primary harmonic eliminator 8 adopts a horizontal installation mode, so that the space is greatly saved, and the total volume of the harmonic eliminating voltage transformer is smaller than that of the existing design. The invention also provides a performance test method of the inrush current suppression type voltage transformer based on the current-sensitive resistance technology, which effectively verifies the suppression effect of the inrush current suppression type voltage transformer based on the current-sensitive resistance technology on the inrush current problem of the voltage transformer during working through a design comparison experiment, and the experiment shows that under the normal operation working condition, the resistance of the current-sensitive primary resonance eliminator 8 is in a low-resistance state, the installation of the current-sensitive primary resonance eliminator 8 does not affect the performances of the secondary winding voltage transformer 6, and simultaneously, the parameters of the system cannot be obviously changed; when ferromagnetic resonance occurs, the flow-sensitive primary resonance eliminator 8 can suppress inrush current in a short time, thereby eliminating resonance continuously and rapidly; under overvoltage, the current-sensitive primary resonance eliminator 8 can effectively control the exciting current of the secondary winding voltage transformer 6 below a threshold value, and normal operation of the circuit is ensured.
Example 2:
referring to fig. 3-9, the difference between the embodiments of the present invention is:
respectively carrying out simulation tests when the neutral point of the voltage transformer is directly grounded and the neutral point of the inrush current suppression type voltage transformer is directly grounded under 2 working conditions, namely, the single-phase grounding is carried out, and collecting the three-phase voltage of the voltage transformer A, B, C and the current between the neutral point and the ground.
And comparing the voltage of the overvoltage transformer A and the amplitude of the current between the neutral point and the ground under two working conditions, and verifying the ferromagnetic resonance eliminating capability of the inrush current suppression type voltage transformer. The experimental schematic is shown in fig. 3.
Test equipment and parameters:
1. a voltage regulator: TSJA-250KVA
2. A transformer: S11-M-160/A
3. Simulating an overhead cable: 4.2km
4. Current to ground: 4.2A
5. The capacitor C1/C2/C3 is connected in series with 2.305uF, and the phase is as follows: 0.242uF
6. Inductance L1/L2/L3:2.78mH
7. An oscilloscope: HS 45 MHZ
8.CT:0.5A/V
PT of 10kV PT
The test working conditions of the tested object are firstly and secondly corresponding to the following two conditions respectively:
firstly, a common voltage transformer experiment;
secondly, an inrush current suppression type voltage transformer experiment is carried out;
the test steps are as follows:
s1, connecting the circuit according to the working conditions I and II, and collecting 3 times of test oscillograms in each working condition, as shown in figures 4-6.
One common voltage transformer with direct earthing neutral point (total 3 times acquisition)
Table 1: working condition is that data statistical table
Secondly, an inrush current suppression type voltage transformer experiment:
table 2: working condition 2 lower data statistical table
According to working conditions (i) and (ii), summarized data of each working condition are as follows:
table 3: working conditions of first and second data statistical tables
And (4) test conclusion:
under the condition of the same circuit parameters, under the 2 working conditions, the limiting effect of the direct grounding working condition of the inrush current suppression type voltage transformer on the current is obvious, the maximum value of the current is about 0.04A-0.2A and is far lower than the rated current of PT (potential transformer) insurance, the inrush current generated during single-phase grounding is effectively suppressed, and the scheme for optimally limiting the single-phase grounding to cause ferromagnetic resonance overvoltage control is provided. Under the working condition, the PT neutral point is directly grounded and has the maximum current for the voltage transformer, and the peak value of the rated current of the PT fuse is exceeded.
After the single-phase ground fault is removed, the faulty phase is to be restored from the ground voltage to the phase voltage, and the normal phase is to be dropped from the line voltage to the phase voltage. During this phase voltage change the charge stored in the phase-to-ground capacitors of the grid needs to be redistributed. In a system with a non-grounded neutral point, only the PT neutral point is grounded, and these charges must be looped through the PT winding and the neutral point. Due to the saturation characteristics of the PT core, the surge of impact through the PT can reach very high amplitudes. As the length of the line increases, the capacitance value of the power grid to the ground increases or intermittent arc grounding occurs (which can be understood as multiple single-phase grounding disappearance processes occurring in a short time), the duration of the three-phase current inrush current of the voltage transformer A, B, C will further increase, so that PT saturation is easily caused to induce ferromagnetic resonance, and the probability of PT explosion insurance will also increase.
The inrush current suppression type voltage transformer can effectively suppress current flowing between a PT neutral point and the ground and PT primary side current when single-phase grounding disappears, and avoids burning out PT due to excitation current surge. Meanwhile, when the system works normally, the zero-sequence current is very small, the PT opening triangular voltage is almost zero, and the secondary side relay protection action cannot be influenced. When single-phase grounding occurs, the PT opening triangular voltage amplitude is not obviously changed.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (7)
1. The utility model provides an inrush current suppression type voltage transformer based on current sensing resistor technique, including the device body, the device body is including unable adjustment base (1) and closed installation casing (2), its characterized in that: the closed installation shell (2) is fixedly connected to the fixed base (1), a first high-voltage winding (3), a second high-voltage winding (4) and a third high-voltage winding (5) are fixedly installed inside the closed installation shell (2), the tail ends of the first high-voltage winding (3), the second high-voltage winding (4) and the third high-voltage winding (5) are in short circuit, and the head ends of the first high-voltage winding (3), the second high-voltage winding (4) and the third high-voltage winding (5) correspond to the three ends of external three-phase power respectively; and secondary winding voltage transformers (6) are fixedly mounted on the first high-voltage winding (3), the second high-voltage winding (4) and the third high-voltage winding (5), the first high-voltage winding (3), the second high-voltage winding (4) and the third high-voltage winding (5) respectively form corresponding voltage mutual induction units with the corresponding secondary winding voltage transformers (6), and a flow-sensitive harmonic elimination mechanism is mounted between the adjacent voltage mutual induction units.
2. The inrush current suppression type voltage transformer based on the current sensing resistor technology as claimed in claim 1, wherein: the current-sensitive harmonic elimination mechanism comprises a conductive groove (7) and a current-sensitive primary harmonic eliminator (8), the conductive groove (7) is a metal flange groove, the conductive groove (7) is fixedly connected to the outer side wall of the closed installation shell (2) between the voltage mutual induction units, the current-sensitive primary harmonic eliminator (8) is further connected with a connecting mechanism (9), and the current-sensitive primary harmonic eliminator (8) is inserted into the conductive groove (7) through the connecting mechanism (9); and a binding post is also fixedly connected on the side wall of the flow-sensitive primary harmonic eliminator (8).
3. The inrush current suppression type voltage transformer based on the current sensing resistor technology of claim 2, wherein: the connecting mechanism (9) comprises a conductive column (901), the conductive column (901) is fixedly connected to the bottom end of the flow-sensitive primary resonance eliminator (8), a metal connecting lug (902) is fixedly connected to the side wall of the conductive column (901), a columnar bump (903) is fixedly connected to the outer side edge of the metal connecting lug (902), and metal elastic sheets (904) are fixedly connected to the upper surface and the lower surface of the metal connecting lug (902); one end of the current-sensitive primary harmonic eliminator (8) is horizontally inserted and connected onto the conductive groove (7) through a connecting mechanism (9) and is connected with the neutral point of the adjacent high-voltage winding in series, and the other end of the current-sensitive primary harmonic eliminator (8) is grounded.
4. The inrush current suppression type voltage transformer based on the current sensing resistor technology of claim 3, wherein: the temperature sensor and the current sensor are integrally installed in the secondary winding voltage transformer (6), a temperature signal uploading interface is fixedly connected to the temperature sensor and used for measuring the operating temperature of the voltage transformer (6) in real time, and a current signal uploading interface is fixedly connected to the current sensor and used for collecting current flowing on the current-sensitive primary harmonic eliminator (8).
5. The inrush current suppression type voltage transformer based on the current sensing resistor technology as claimed in claim 1, wherein: the method also comprises a performance test method of the inrush current suppression type voltage transformer, and specifically comprises the following steps:
s1, designing a comparison experiment, wherein a common voltage transformer is used as a comparison group of the experiment, the device body is used as an experiment group, and the common voltage transformer and the experiment group are connected into the same experiment circuit;
s2, directly grounding neutral points of the control group and the experimental group, performing a simulation experiment, connecting a circuit, and collecting three-phase voltages of the overvoltage transformers flowing in the control group and the experimental group and current between the neutral points and the ground by using an oscilloscope;
s3, arranging the voltage and current data of the control group and the experimental group acquired in the S2, and carrying out graph acquisition on the data through an oscilloscope;
and S4, processing and analyzing the data obtained in the S3, and verifying the capability of the device body and the common voltage transformer for eliminating the ferromagnetic resonance.
6. The inrush current suppression type voltage transformer based on the current sensing resistor technology of claim 5, wherein: the step of connecting the device body to the experimental circuit in S1 specifically includes the steps of:
a1, testing a flow-sensitive primary harmonic eliminator (8) of the flow-sensitive harmonic elimination mechanism, and testing the insulation resistance of the flow-sensitive primary harmonic eliminator (8) by using a 1000V megger;
a2, judging whether the current-sensitive primary resonance eliminator (8) is normal or not according to the insulation resistance value measured by A1, if the insulation resistance value is 40-210 k omega, indicating that the current-sensitive primary resonance eliminator (8) is normal, installing the current-sensitive primary resonance eliminator (8) into a conductive groove on the outer side wall of the device body closed installation shell (2) through a connecting mechanism at the bottom end of the current-sensitive primary resonance eliminator (8), otherwise, replacing elements of the current-sensitive primary resonance eliminator (8), and repeating the operation of A1;
a3, after the operation of A2 is completed, the bottom end of the current-sensitive primary harmonic eliminator is grounded, meanwhile, the other end of the current-sensitive primary harmonic eliminator is connected into an experimental circuit in series through a lead and a binding post, wherein the first high-voltage winding (3), the second high-voltage winding (4) and the third high-voltage winding (5) are connected with a three-phase circuit of the experimental circuit, and the head ends of the first high-voltage winding, the second high-voltage winding and the third high-voltage winding correspond to three ends of three-phase electricity respectively; the tail ends of the first high-voltage winding (3), the second high-voltage winding (4) and the third high-voltage winding (5) are connected with a grounding circuit of the experimental circuit in series.
7. The inrush current suppression type voltage transformer based on the current sensing resistor technology as claimed in claim 5, wherein: the method further comprises the steps of connecting the device body to an experimental circuit under the condition that the flow-sensitive primary harmonic eliminator (8) is not installed, using the device body as a new experimental group, repeating the operations from S2 to S4, and verifying the performance of the device body in inhibiting the primary neutral point inrush current of the voltage transformer.
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