Development of sensor scanning type space charge measurement system

Non-destructive space charge measurement techniques have been used to investigate space charge behavior in insulating materials. Real time space charge measurement systems are also required to observe the localized space charge distribution in insulating materials. Since the space charge behavior is generally in transient, a real time measurement system will be also required in the two or three (2D or 3D) dimensional space charge measurement systems. In the pulsed electro-acoustic (PEA) method, the three dimensional (3D) space charge measurement systems using acoustic lens have been developed, and the real time 2D space charge measurement system has been also developed using multi-sensor array. However, the 3D system takes measuring time of movement of the lens and the 2D system takes cost of system because A/D converters must be connected to each sensor in the sensor array. A 2D dimensional space charge measurement system in lateral and thickness direction for transient space charge has been developed using the sensor array and semiconductor analog switch unit in the PEA method. In this report, fundamental performances of the developed 2D space charge measurement system are introduced.