Lock-in Calibration for Space Charge Measurement

Space charge will inevitably appear in practical applications, like cables that have been applied HVDC, in which space charge is concerned to be existed. As the space charge distribution has a strong link with the degradation of insulation material and it also is a core point for insulation technology upgrade. So, a method to observe space charge in insulation material is needed, to certain if it exists or not. The presentation will deal with the acquisition of the reference signal when the pulsed electroacoustic measurement on space charge in insulating materials is carried out. By superposing pulse voltage on specimens made by XLPE films which is applicated -3kV and -4kV DC voltage, a method as lock-in acquisition to take the reference signal at the same time of the acquisition of the target signal is proposed.