Space And Surface Charge
Techniques available for the measurement of space charge within the laboratory include Pulsed Electroacoustic (PEA) measurements and Laser Induced Pressure Pulse (LIPP) measurements. The majority of our research is concerned with polymeric insulating materials used for power transmission cables, in both planar and cable geometries, under either DC or AC electric stress.Typical applications of space charge measurements include:
- The effect by space charge on electric stress modification.
- Material evaluation of dielectrics such as epoxy resins, low density polyethylene and crosslinked polyethylene.
- The study of electrical ageing.
Apart from insulating materials, trapped charge within piezoelectric materials and glass can now be measured with our improved PEA system that has a spatial resolution of 5 μm.
Dynamic surface charge is measured using a Pockels cell. This approach ensures that surface charge is not influenced by the measurement itself, it allows not only different materials to be studied but also the effect of local environment on surface charge behaviour. The technique uses a fast CCD camera with microscope lens and this ensures both good spatial and temporal resolution (typically one pixel represents a surface area of 10x10μm monitored at 1000fps) Current research on surface charge is funded by National Grid and is concerned with investigating the phenomena of surface charging of GIS spacers.
Featured ProjectDC conductivity measurement of transformer oils and its application in diagnosis of oil status
Most Recently Added Publications
Alghamdi, H A, Chen, G and Vaughan, A S (2013) A New Electro-Thermal Aging Model Based on Trapping and De-trapping Process in Polymeric Materials. In, Dielectrics 2013, Reading, GB, 10 - 12 Apr 2013. , 15-16.
Lau, K Y, Vaughan, A S, Chen, G, Hosier, I L and Holt, A F (2013) Absorption Current Behaviour of Polyethylene/Silica Nanocomposites. In, Dielectrics 2013, 10 - 12 Apr 2013. , 24-25.