SYSTEM FOR TESTING POWER CABLE LINES Russian patent published in 2022 - IPC G01R31/14 G01R31/58 

FIELD: power equipment insulation testing.

SUBSTANCE: invention relates to systems for testing the insulation of power equipment and can be used to test power cable lines with XLPE insulation or other objects with a large insulation capacitance. The system for testing power cable lines contains an AC voltage amplitude modulation device to create a sinusoidal "extra low frequency" (ELF) amplitude modulation; step-up AC voltage transformer connected in a circuit with an amplitude modulation AC voltage device to obtain a sinusoidal-amplitude-modulated AC voltage ELF-VN; a high-voltage module in a circuit with a step-up AC voltage transformer for demodulating a sinusoidal-amplitude-modulated AC voltage ELF-VN to obtain sinusoidal electric waves ELF-VN; the high-voltage module, located in a closed housing, contains: a rectifier in a circuit with a step-up transformer; an output circuit for connecting the high-voltage module to AC power cable lines for supplying high-voltage sinusoidal ELF electric waves; a high voltage switching system including a polarity reversal device in a circuit between the rectifying device and an output circuit for supplying high voltage ELF sinusoidal electrical waves to the output circuit, and high voltage switching of resistive discharge paths, which includes a plurality of resistive discharge paths composed of a plurality of resistors; high voltage polarity switches; many magnetic contactors; many high-voltage contacts; many electromagnets; fan. The high-voltage module is made with the possibility of cooling its elements. The amplitude modulation device is made in the form of a non-contact electronic voltage regulator that forms a sinusoidal low-frequency envelope, has the function of automatically limiting the output current at a given level, connected to a digital control system, through which the overall control of the test system is carried out. The elements of the high-voltage module are in the air. During the operation of the fan system, an intense air flow is created, which cools the high-voltage switches and resistors, as well as extinguishing the electric arc that occurs when the high-voltage contacts are closed. The high-voltage switching system is made with the possibility of changing the polarity.

EFFECT: increasing the reliability of operation and reducing the labor intensity of servicing the system for testing power cable lines, increasing the efficiency of arc extinguishing, providing a mode for maintaining breakdowns, generating a constant voltage of any polarity, the ability to save test results.

1 cl, 4 dwg