CN102393497A - Portable electronic transformer polarity calibrator - Google Patents

Abstract

The invention discloses a portable electronic transformer polarity calibrator.A lithium battery charges a high-voltage capacitor through a DC/DC converter, the DC/DC converter sends charging information to a PWM controller, the PWM controller is connected with a battery management unit, a capacitor management unit, the DC/DC converter, an operation control unit and a display unit and performs output control on the units, a series resistor is connected behind the high-voltage capacitor, the capacitor management unit is connected with the high-voltage capacitor, and the operation control unit sends a command signal for measurement. The invention has the characteristics of accurate polarity judgment, interference resistance, portability, simple operation and the like.

Description

Portable electronic transformer polarity calibrator

technical field

The invention is a portable electronic transformer polarity calibrator, which is suitable for the electronic transformer polarity calibration and belongs to the technical field of electric power automation.

Background technique

The transformer is one of the most basic and important equipment in the power transmission and transformation system. It is the front-end sensor of various electrical parameters during the operation of the power grid. dependent signal source. The correctness of the polarity of the transformer plays a vital role in the operation of the secondary system of the power grid, and it is directly related to whether the system equipment can work normally.

In order to prevent the polarity error of the transformer during operation, a polarity check must be carried out before the transformer is put into operation to ensure that the polarity of the transformer is correct. The principle of the electronic transformer is different from the traditional transformer. The traditional electromagnetic transformer realizes the current transformation through the principle of electromagnetic induction. The polarity of the transformer can be observed through the DC pointer meter by using the dry battery point polarity method.

There are two main types of electronic transformers currently operating online: one is the hollow coil type (Rogowski hollow coil), and the other is the pure optical magneto-optical glass type. The basic working principle of Rogowski coil (Rogowski hollow coil) electronic transformer: Rogowski coil induces a voltage signal and then calculates it through the integrator. The signal is converted into an optical signal at the high voltage end and then transmitted to the low voltage side through the optical fiber. The basic working principle of the pure optical electronic transformer: the pure optical electronic transformer obeys the law of the Ampere loop, uses the Faraday magneto-optic effect principle, installs the Faraday magneto-optic effect element in the magnetic field generated by the primary current conductor, and then measures the line The optical signal quantity of the polarization plane of the polarized light is transmitted to the secondary processing system through the optical fiber to obtain the primary quantity. Whether it is a Rogowski coil electronic transformer or a pure optical electronic transformer, they all provide digital signals and use optical fiber to transmit signals. Since the electronic transformer uses new principles and new technologies, the original test method is no longer suitable for the verification of the polarity of the electronic transformer. A new type of device is needed to verify the polarity of the electronic transformer.

Patent No. 200910026359.5 provides a polarity test method for electronic transformers. Use the relay protection tester to check the polarity of the electronic transformer. The relay protection tester applies pulse current to the electronic transformer and judges the polarity of the transformer according to the waveform.

The above-mentioned patents are different from the present invention: the content of the patent "Polarity Test System and Polarity Test Method for Electronic Transformer" only provides a method for polarity test of electronic transformers, while this patent invented a Electronic transformer polarity calibration device. The patent "Polarity Test System and Polarity Test Method of Electronic Transformer" uses the current pulse output by the relay protection tester, while this patent uses the discharge of a high-voltage capacitor to generate a high current pulse. The principle of current pulse generation is different. "Electronic Transformer Polarity Test System and Polarity Test Method" patent In the actual field test, the relay protection tester can only output 10-30A of current. The electromagnetic environment of the substation is relatively complex, and the minimum code values of the electronic current transformers with different transformation ratios correspond to different primary current values. In the case of large transformation ratios or abnormal electromagnetic environments, the above patents cannot achieve the purpose of polarity verification. This patent comprehensively considers the factors affecting the polarity test in the complex environment such as the test site, and proposes a portable electronic transformer polarity calibrator to generate a high pulse current of 100-600A, which can obtain a clear pulse signal and accurately determine the electronic transformer polarity. transformer polarity.

Contents of the invention

The technical problem to be solved by the present invention is to provide a portable electronic transformer polarity calibrator.

Technical scheme of the present invention is realized like this:

The lithium battery charges the high-voltage capacitor through the DC/DC converter, and the DC/DC converter sends the charging information to the PWM controller, and the PWM controller is connected to the battery management unit, capacitor management unit, DC/DC converter, operation control unit and display unit, and control the output of the above-mentioned units, the high-voltage capacitor capacitor is connected with a series resistor, the capacitor management unit is connected with a high-voltage capacitor, and the operation control unit sends out a command signal for testing life.

There are two sets of series resistors, one is the charging circuit resistance, and the other is the discharging circuit resistance.

The lithium battery charges the high-voltage capacitor through a DC/DC converter.

The calibrator generates a large pulse current of 100-600A.

The advantages of the present invention are: 1. The portable electronic transformer polarity calibrator of the present invention can apply a high pulse current to the transformer, and its pulse current can reach 100-600A, and the obtained test data is true and reliable, and can accurately determine Electronic transformer polarity. 2. Instantly display the output value, and at the same time judge the polarity of the electronic transformer according to the wave recording of the transformer pulse, with high real-time performance. 3. The calibrator has simple wiring and easy operation. Just connect the positive and negative poles of the calibrator with the electronic transformers P1 and P2, and operate the discharge control switch. 4. No need for external power supply, portable.

Description of drawings

Fig. 1 is a schematic structural diagram of a portable electronic transformer calibrator in the present invention

Fig. 2 is the wiring schematic diagram of electronic transformer polarity experiment in the present invention

Fig. 3 is the wiring schematic diagram of the polarity checking experiment of the electronic transformer in a certain 750kV intelligent substation of the present invention

Fig. 4 a is the forward pulse experimental diagram of 750kV electronic current transformer among the present invention

Fig. 4b is the negative pulse experiment diagram of 750kV electronic current transformer in the present invention

Detailed ways

The content of the present invention will be further described below in conjunction with the accompanying drawings and examples.

The lithium battery charges the high-voltage capacitor through the DC/DC converter, and the high-voltage capacitor discharges the electronic transformer to generate a current pulse, and the transformer will produce a transient response. The polarity of the electronic transformer can be verified by comparing the relationship between the rising or falling transient process of the waveform and the direction of the applied current pulse and the connection of the transformer. The waveform sampling is intuitively displayed to the experimenter through the message acquisition device and the graphics processing system, and the experimenter can conveniently and quickly analyze the polarity of the electronic transformer according to the data waveform data.

The portable electronic transformer polarity calibrator described in the present invention applies a pulse current to the electronic transformer, and then transmits the working status and real-time data of the electronic transformer to the message analysis device through the data collector, Analyze the collected data, and then use the waveform visualization module to obtain the waveform graph of the data value, and conduct in-depth analysis on the sampled value. The polarity of the electronic transformer can be analyzed by comparing the data sampling value with the value applied on the primary side of the electronic transformer.

specific experiment

The two stages of the electronic transformer are connected to the polarity of the calibrator. When the charging gear is selected, it is charging. When the charging voltage remains unchanged, the charging ends; when the testing gear is selected, the calibrator discharges the electronic transformer. , the electronic transformer produces a transient response, the wave recorder records the pulse waveform, and the test ends. Determine the polarity of the electronic transformer according to the waveform diagram displayed by the wave recorder and the connection mode between the polarity of the electronic transformer and the polarity of the calibrator.

The invention is applied to the polarity checking experiment of the electronic transformer of a certain 750kV intelligent substation, and has achieved good results. The field wiring diagram is shown in Figure 2.

Fig. 2 is the wiring diagram of the electronic transformer polarity experiment in the present invention, and Fig. 3 is the wiring diagram of the present invention in the polarity checking experiment of the electronic transformer in a 750kV intelligent substation. Connect the portable electronic transformer polarity calibrator to the circuit, disconnect the isolating switches k1 and k3, close the isolating switches k2 and k4, and test the polarity of the electronic transformers p1 and p2. At the beginning of the experiment, the portable electronic transformer polarity calibrator applies a pulse current to the electronic transformer, and the pulse signal (optical signal) generated by the electronic transformer is transmitted to the wave recording analysis device through the merging unit. The polarity waveform of the electronic transformer can be obtained by visual processing. If the polarity of the electronic transformer is the same as that of the portable electronic transformer polarity calibrator, the oscilloscope will display the waveform as shown in Figure 4a, and the waveform will show a positive pulse. If the polarity of the electronic transformer is opposite to that of the portable electronic transformer polarity calibrator, the oscilloscope will display a waveform as shown in Figure 4b, and the waveform will show a negative pulse.

Fig. 4a is the forward pulse experiment diagram of the electronic current transformer of a certain 750kV intelligent substation in the present invention

Fig. 4b is the negative pulse experiment diagram of the electronic current transformer of a certain 750kV intelligent substation in the present invention

The positive terminal of the portable electronic transformer polarity calibrator is connected to the p1 pole of the electronic current transformer, and the applied current can reach 100-600A. The polarity direction of the electronic current transformer can be judged from Figure 4, which is accurate and clear The polarity waveform of the electronic current transformer is accurately recorded, and the polarity can be judged quickly.

Claims (3)

1. A portable electronic transformer polarity calibrator, comprising a high-voltage capacitor, a capacitor management unit, a DC/DC converter, a PWM controller, a series resistor, an operation control unit, a display unit, a lithium battery and a battery management unit, It is characterized in that the lithium battery charges the high-voltage capacitor through the DC/DC converter, and the DC/DC converter sends the charging information to the PWM controller, and the PWM controller is connected to the battery management unit, the capacitor management unit, the DC/DC converter, and the operation Control unit and display unit, and control the output of the above units. The high-voltage capacitor capacitor is connected with a series resistor, the capacitor management unit is connected with a high-voltage capacitor, and the operation control unit sends a command signal to test life. There are two sets of series resistors, one is the charging circuit resistance , and one group is the discharge circuit resistance. 2. The portable electronic transformer polarity calibrator according to claim 1, wherein the lithium battery charges the high-voltage capacitor through a DC/DC converter. 3. The portable electronic transformer polarity calibrator according to claim 1, characterized in that the calibrator generates a large pulse current of 100-600A. the

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