System and method for pea space charge measurement of full-scale high-voltage DC cable under temperature control gradient

Abstract

The invention discloses a PEA space charge measurement system under a full-size high-voltage direct current cable temperature control gradient. The system comprises a direct current cable insulation layer temperature gradient control device (2), an electrode system (3), a PEA space charge measurement device (4) and an external measurement control device (6). The direct current cable insulation layer temperature gradient control device is provided with a closed space surrounding a test cable, the electrode system (3) is connected to the test cable inside the closed space and is connected with a high-voltage impulse source (5) outside the closed space through a wire, the PEA space charge measurement device (4) is connected to the electrode system (3), and the external measurement control device (6) is located outside the closed space and is connected with the PEA space charge measurement device (4). The PEA space charge measurement system and method are used for space charge measurement of an insulation layer of a full-size high-voltage direct current cable under the temperature control gradient in the research and development test period, the prequalification test period, the load cycle test period and the long-term aging test period, and the high resolution ratio and measurement precision can be achieved.

Description

technical field [0001] The invention relates to a PEA (electroacoustic pulse method) space charge measurement system under the temperature gradient control of a full-scale high-voltage direct-current cable. The system is based on the PEA measurement method and can be used for a full-scale high-voltage direct-current cable (engineering application level, such as a voltage level of 160kV) or above, insulation thickness between 10mm and 20mm) space charge measurement of extruded insulation layers (such as cross-linked polyethylene XLPE) under controlled temperature gradients during development tests, pre-qualification tests, load cycle tests and long-term aging tests. The present invention also relates to a method for measuring the space charge of a full-scale high-voltage direct current cable under a temperature gradient controlled by PEA (pulse electroacoustic method) using the above-mentioned system. Background technique [0002] In recent years, HVDC transmission technology...

AI Technical Summary

Problems solved by technology

[0007] Finally, the metal electrode in the existing coaxial model cable PEA measurement system is processed into a fan shape to fit the cable with a cylindrical outer surface. This electrode design is only suitable for a single-sized cable sample. Once the outer diameter of the cable changes Changes, the original electrode system will no longer be applicable, which will bring great inconvenience to the measurement

For another flat electrode design, when measuring large-sized cables, it will be difficult to ensure that the measurement is carried out at the same fixed point due to the temperature change caused by the change of the test load and the influence of the self-weight of the PEA measurement device.

Images