Test and diagnostic system for high voltage cables up to 230 kV HV DAC 270

The HV DAC 270 high-voltage complex is a set of test equipment using a damped alternating voltage (DAC) source with a maximum value of 270 kV. The test set can be used to carry out acceptance tests in accordance with IEC 62067 for cables with rated voltages up to 230 kV. The system can also be used to analyze the technical condition of old cable lines. The main area of ​​application of DAC test systems is the detection, evaluation and location of partial discharges (PD) in cable insulation and fittings of all types of high-voltage power cables. The presence of PD is a sign of slowly developing insulation failures, based on this technique is considered one of the best for the purpose of early detection of aging of the insulation of high and medium voltage cables. Since the frequency of the test voltage DAC is close to the nominal frequency of the operating AC voltage, then all cases of recorded PD activity can be objectively assessed as corresponding to the actual operating conditions of the cables. Due to the attenuation of the test voltage, it is easy to determine the values ​​of the onset (PDIV) and damping (PDEV) voltages of the PD. Critical PD levels characterizing the degree of insulation degradation serve as important evaluation criteria. Analysis and evaluation of the parameters of a typical PD, as well as determining the place of its occurrence, help to set criteria for the reliability of equipment during its operation, as well as to plan maintenance or replacement work. The system consists of a laptop, which is used as a control unit, and a high-voltage part. The high voltage part (HV) includes a high voltage source, an electronic switch and a resonant inductor that generates a damped AC test voltage. The high voltage divider and coupling capacitor used for PD detection and localization are combined in a separate unit.

Storage, analysis and processing of the received information is carried out in a laptop. These works can be performed both in the field and in the office. All units of the system are stored in separate transport boxes (suitcases) that can be transported by air.