CN102043099A - Device for testing dielectric loss at high voltage - Google Patents

Abstract

The invention belongs to the technical field of power system detection and discloses a device for testing dielectric loss under high voltage, which is composed of a variable frequency power supply controller, an excitation transformer, a voltage divider, a high-voltage standard capacitor, a dielectric loss testing bridge and at least one The above compensating reactors are connected in series, wherein, the variable frequency power supply controller, the excitation transformer, the compensating reactor and the parallel circuit formed by the voltage divider and the high voltage standard capacitor are sequentially connected in series to form a power line, and the power output end of the power line is connected to the On the test equipment, the variable frequency power supply controller is connected to an AC power supply, and the dielectric loss test bridge is connected to the device under test through a signal transmission line. The device can realize the accurate test of the dielectric loss of electrical equipment under high voltage, and the device has the advantages of reasonable structure design, easy operation, small power supply capacity, no need for overvoltage protection, small size, light weight, simple wiring, etc., especially Suitable for field use.

Description

A device for testing dielectric loss under high voltage

technical field

The invention belongs to the technical field of power system detection, in particular to a device for testing dielectric loss under high voltage.

Background technique

In the well-known electric power technology, "Electrical Equipment Installation Engineering Electrical Equipment Handover Test Standard" stipulates that the dielectric loss voltage should be measured at 10Kv. When there is doubt about the insulation performance, the dielectric loss test should be carried out under high voltage. However, the measurement voltage of our existing equipment for dielectric loss can only reach 10Kv. When there is doubt about the insulation performance of the equipment, we can only strengthen the chromatographic analysis of insulating oil, but cannot conduct dielectric loss tests under high voltage, so that the equipment cannot be accurately judged. If the insulation condition is poor, it is easy to cause equipment operation failure. So far, this problem has not been satisfactorily resolved.

Contents of the invention

The object of the present invention is to provide a device for testing the dielectric loss of electrical equipment under high voltage, accurately judging the insulation condition of the equipment, and reliably ensuring the normal operation of the electrical equipment.

The technical solution adopted to realize the object of the present invention is: the device is composed of a variable frequency power supply controller, an excitation transformer, a voltage divider, a high voltage standard capacitor, a dielectric loss test bridge and at least one compensation reactor connection, wherein, The variable frequency power supply controller, excitation transformer, compensation reactor and the parallel circuit composed of voltage divider and high voltage standard capacitor are connected in series to form a power supply line. The power output end of the power supply line is connected to the equipment under test, and the variable frequency power supply controller is There is an AC power supply, and the dielectric loss test bridge is connected to the device under test through a signal transmission line.

The device for testing dielectric loss under high voltage made according to the above scheme can realize accurate testing of dielectric loss under high voltage of electrical equipment, thereby ensuring reliable operation of electrical equipment, and the device has reasonable structure design, easy operation, and requires power supply capacity Small, no need for overvoltage protection, small size, light weight, simple wiring and other advantages, especially suitable for field use.

Description of drawings

Fig. 1 is a schematic structural view of the present invention.

Detailed ways

As shown in Figure 1, the device of testing dielectric loss under the high voltage of the present invention is made of variable frequency power supply controller 2, excitation transformer 3, voltage divider 5, high voltage standard capacitor 6, dielectric loss testing electric bridge 9 and at least 1 The above compensating reactors 4 are connected in series, wherein the variable frequency power supply controller 2, the excitation transformer 3, the compensating reactor 4, and the parallel circuit formed by the voltage divider 5 and the high voltage standard capacitor 6 are sequentially connected in series to form a power line. The power output end of the power line is connected to the device under test 7, the variable frequency power controller 2 is connected to the AC power supply 1, and the dielectric loss test bridge 9 is connected to the device under test 7 through a signal transmission line. In the power line, the number of compensating reactors 4 is determined according to the inductance parameter and test frequency of a single compensating reactor. The variable frequency power supply controller 2, excitation transformer 3, compensation reactor 4, voltage divider 5, high voltage standard capacitor 6 and dielectric loss test bridge 9 can all be directly purchased in the market, and their structures will not be described in detail. Number 8 in the figure is an electric bridge connecting the voltage divider 5 and the high-voltage standard capacitor 6 . When the device is used to measure the dielectric loss under high voltage, the transformer is mainly a capacitive load. Using the different properties of inductive reactance and capacitive reactance, the variable frequency power supply controller 2, excitation transformer 3, compensation reactor 4, voltage divider The device 5 and the high-voltage standard capacitor 6 together form a series resonance test power supply, which can greatly reduce the capacity of the test power supply, has a good output current waveform, has an automatic frequency modulation function, and requires a small power supply capacity and does not need overvoltage protection. At the same time, using the series resonant line as the test power supply has the advantages of small size, light weight, and easy wiring, and is especially suitable for on-site use. In addition, the device uses a dielectric loss test bridge 9 as a dielectric loss tester, which is connected to the device under test 7, and can directly measure the dielectric loss under high voltage.

Claims (1)

1. A device for testing dielectric loss under high voltage, characterized in that: it is connected by variable frequency power controller, excitation transformer, voltage divider, high voltage standard capacitor, dielectric loss testing bridge and at least one compensation reactor Composition, wherein, the frequency conversion power supply controller, the excitation transformer, the compensation reactor and the parallel circuit formed by the voltage divider and the high voltage standard capacitor are sequentially connected in series to form a power line, and the power output end of the power line is connected to the equipment under test, and the frequency conversion The power controller is connected with an AC power supply, and the dielectric loss test bridge is connected with the device under test through a signal transmission line.