The magnetic and electrical properties of superconductors were a challenge for many inventors and designers to use superconducting materials in the construction of fully superconducting voltage and current sources commonly called fluxpumps. In the past twenty years a large variety of mechanically or electrically driven devices have been proposed an d successfully operated. In this review the basic principle of operation of each class of devices is shown and specific material problems and limitations are reported. The review will be published in two parts.

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This paper forms the second part of the review. Full and half wave superconducting transformer rectifiers are analysed. Modes of operation and loss mechanisms are detailed and a comparison between the behaviour of dynamos and rectifiers is presented. Investigations carried out to date still leave the flux pump relatively a long way from real applications. The possible use of a flux pump in a large magnet system and for the general protection of that system merits further study.

In the framework of the development of an experimental 10 T Nb3Sn dipole coil for the LHC at CERN the effects of transverse stress on Rutherford type of Nb3Sn cables have been investigated. For this purpose a special facility was designed and taken into operation in which the voltage-current behaviour of short pieces of Nb3Sn cables can be investigated in a background field up to 11 T and an applied stress of 300 MPa. The repulsive Lorentz force of 250 kN, generated by a set of superconduct9g coils, is used to impress the cable over an area of 20x42 mm maximum, in presence of a transport current up to 40 kA. In this paper the testing equipment is described and the fiist results of the observed critical current degradation of two Nb3Sn cables are discussed. It was found, that current reduction starts immediately upon loading and that already at transverse compressive stress of 100 MPa the critical current at 11 T is reduced by more than 20 % for one cable and even about 60 % for the other one. Furthermore, it seems, that the edges of the Rutherford type of cable are much more sensitive to the applied force than the cross-over points of the strands.

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