HVDC cable load cycle system is a key equipment for the research of the insulation properties in full-sizecable

and its chief function is to control both the conductor temperature and the temperature gradient across the in-sulation precisely. Aiming to study the influence of the flow rate of the temperature-control medium on the conductortemperature and the temperature gradient across the insulation in the ±500 k V HVDC cable load cycle system

a fi-nite element model of the water cycle channel was established in COMSOL Multiphysics

and the thermo-fluid-solidcoupling simulations of the HVDC cable

circulating water

and thermal insulation pipe were carried out. The axialdifferences of the conductor temperature and temperature gradient across the insulation were studied by controllingthe flow rate of the water

and the water temperature and the current were also corrected. The results showed that thewater’s temperature fluctuation reduced with the increasing of its flow rate

and when the latter was 0.3 m/s

the axi-al differences of both the conductor temperature and temperature gradient were less than 1 ℃. The iterative calcula-tion method of the water temperature and current magnitude was proposed

which could limit the errors of the conduc-tor temperature and temperature gradient within ±1 ℃ to meet the demand of the temperature control in the cableload cycle system.