ISEIM 2014 - DEI/IEEJ

General info > PEA meas. special session

Special session for space charge measurement technology including demonstration and tutorial programs

Introduction
The broad HVDC power network is getting to move forward with full-scale implementation, especially in Europe area. In order to estimate the HVDC stress on insulating materials, space charge distribution with the pulsed electro-acoustic (PEA) method - based measurement has been paid much attention. The organizing committee is planning to hold a special session introduces the advanced technique for measuring the space charge distribution in insulating material using PEA method.

Click here to learn the principal of PEA systems (courtesy to the system manufacturer, Five Lab., Ltd.)

Special Oral Session
One or two oral sessions will be held during the symposium, including key note lectures by invited speakers.

Tutorial Program
This is a practice program to lean the basic space charge measurement for beginners using standard measurement system. Participants can touch the conventional PEA system and learn the procedure of measurement and calibration step by step, conform to the IEC Technical Specification (IEC/TS 62758) procedure.
Note: audiences who want to take part in this program are needed to apply through the registration system. The registration system will be ready soon. We are sorry for your inconvenience.

Demonstration Session
This is a demonstration session of advanced measurement systems brought by some researchers in Japan. Following eight types of state-of-the-art PEA systems will be gathered and audiences can see how they work.
Note: Most of the measurement systems cannot be operated or controlled by audiences. It would also be dangerous during the voltage application. Please follow instructions provided at the conference. The organizing committee is not responsible for any damages if the audience does not follow them.

Conventional PEA (from NICT and Five lab.) : Electric field of the bulk insulating material would be enhanced when space charge is accumulated under high voltage stress. Because of the concerns for electric breakdown, space charge distribution in the bulk material is required to be measured. Conventional PEA system is to measure such charge accumulation behavior using film shape samples.
PEA system to measure thick sample (~27 mm) (from Matsue College Tech.) : The maximum thickness of XLPE layer is 27 mm in a 500 kV class electric power cable. Therefore, it could be important to measure the space charge distribution in thick sample. The present system overcomes problems such as attenuation of acoustic waves during the bulk transportation and mismatch of acoustic impedance.
Simultaneous measurement PEA system (from Tokyo City Univ.) : This system can measure the space charge distribution and external circuit current simultaneously. Based on such a system, the electric field distribution, the displacement current distribution, and the conduction current distribution occur at the same time can be analyzed. Dissipation power can also be calculated to address the concern on the cause of the breakdown of XLPEs under DC high electric field.
Ultra high resolution PEA (from Tokyo City Univ.) : Advances both in pulse generator and piezoelectric sensor are established in this system to achieve the positional resolution of about 1.6 micro-meters.
Space charge measurement system equipped with a measurement function for the acoustic properties (from Toyohashi Univ. Tech.) : The PEA method detects the acoustic pressure due to the space charge in the bulk. Because the acoustic properties of the entire system must be understood to improve the precision of the PEA method, a space charge measurement system equipped with a function to measure the acoustic properties has been developed.
PEA system for full size electric cables (from Toyohashi Univ. Tech.) : will be disclosed soon.
Portable mini PEA (from Tokyo City Univ.) : Nowadays polymeric materials are also used for spacecraft surface materials such as a multi layer insulator and optical solar reflector. Such materials would be charged up due to radioactive rays such as electron and proton irradiation. Such charging up is not only a concern of material degradation, but also of surface discharging, which would result in abnormal spacecraft operation. The system can measure the charge accumulation both at the surface and inside the bulk during the radioactive ray irradiation.
Wire cable PEA (from NICT) : Measurement of the space charge in the insulating layer of the motor windings is required to elucidate the mechanism of unexpected PD generation. Configuration of the insulating layer of winding wire would be different from the film-shaped samples. The system has new apparatus to apply the voltages through two lines for DC and pulse voltages separately.