Gravitational lens systems are useful because they allow study of objects which would otherwise be too faint for existing telescopes. Radio-quiet quasars form about 90% of known quasars, but the physical mechanism of their radio emission is not clear. We have been studying and modelling a sample of such objects, whose unlensed counterparts (with intrinsic flux density of a few microJy) will only become accessible to study when the SKA is built. We have achieved radio detections in a number of these objects, and in some cases can measure structural information on 10 mas (roughly 100pc) scales. The aim of the programme is to assess the significance of the contribution of micro-AGN to the radio emission, compared to emission from more spatially extended starforming regions.