Whole shielding capacitor voltage transformer

Abstract

The invention discloses a wholly shielded capacitor voltage transformer which comprises a capacitor divider part and an electromagnetism device positioned in the sealed casing of filling with the insulating medium. The capacitor divider part is the high-voltage electrode and the medium-voltage electrode positioned in the wholly shielded capacitor voltage transformer, the high-voltage electrode is an electrode at the center, the medium-voltage electrode is a cylinder-shaped electrode with the same shaft of the high-voltage electrode and surrounds the high-voltage electrode. The wholly shielded casing of the capacitor divider part is a cylinder with the same shaft of the high-voltage electrode and surrounds the medium-voltage electrode. The medium-voltage electrode, the high-voltage electrode and the casing are of the structure of the same shaft, the electric field force generated between them evenly distributes at the circumference and offsets mutually under the role of the voltage, the relative position between the electrodes does not shift, the capacitor between the electrodes is extremely stable, thereby promoting the precision of the transformer.

Description

(1) Technical field: [0001] The invention belongs to the field of transformers, and relates to a capacitive voltage transformer used in a power transmission and transformation system, in particular to a fully shielded capacitive voltage transformer. (two) background technology: [0002] In the power system, it is necessary to use the voltage transformer to extract the voltage from the high voltage terminal in proportion to measure the voltage and electric energy, and provide signals to the relay protection circuit. At present, oil-immersed capacitor voltage transformers are commonly used in power transmission and transformation systems. This type of voltage transformer includes a capacitor voltage divider and an electromagnetic device. The high-voltage capacitors and medium-voltage capacitors in the capacitor voltage divider are connected in series by multiple capacitor elements. Composition, installed in the shell filled with insulating oil. This type of transformer has th...

AI Technical Summary

Problems solved by technology

The environmental additional error of the commonly used oil-immersed capacitive voltage transformer reaches 0.3%, and with the increase of the operating voltage, the number of series series of high-voltage capacitors increases correspondingly, and the additional error will increase, which will greatly reduce the transformer in the environment. Accuracy in Measurement and Metering of Power System

[0015] 2. Large dielectric loss

[0016] The dielectric loss tangent of the oil-immersed capacitor voltage transformer is relatively large, about 1.2×10 -3 Left or right, it will generate a large power loss during operation, and cause the temperature to rise, which is not good for the operation of the transformer

[0017] 3. Potential threats to the environment

The leaked insulating oil not only pollutes the environment, but also the high temperature generated by the electrical breakdown causes the overflowed insulating oil to burn in the air, which can easily cause a fire

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