Evaluation of HVDC cables for the St. Lawrence River crossing of Hydro-Quebec´s 500 kV DC line. III. Thermal behavior

For pt.II see ibid., vol.7, no.2, p.1043-9 (1992). The thermal analyses conducted during the different stages of Hydro-Quebec´s St. Lawrence River crossing project are discussed. The impact of the thermal studies on the choice of cable and the design of the installations, the numerous problems faced during the cable prototype and demonstration tests, and the solutions obtained by numerical analysis using the finite-element method are described. These problems were related in part to the temperature controls of the cable and its accessories, and in particular to the control of the temperature gradient across the dielectric material at various locations along the test loop