Abstract: An apparatus for interconnection in a voltage-stiff converter is provided. The converter has at least one phase leg with at least two current valves. The apparatus connects a current valve with a respective pole conductor. A cable extends between an end of the phase leg and a capacitor which defines a direct voltage. The cables attached to different poles are arranged close beside each other and are made of an insulation layer of polymer base which surrounds a conductor.

Abstract: In a method for control of an installation for transmission of high-voltage direct current in dependence on at least one stress parameter for a valve in a converter included in the installation and controlled by control equipment (CE1, CE2), a value (PDR, PDI, UMAX, TRC, TTC) of the stress parameter is continuously calculated, based on predetermined relationships (f1, f2, g1R, g2R, g1I, g2I, h1, h2) and in dependence on measured values (UN, .alpha., .gamma., ID, TO, TI, RECT/INV) of the operating parameters of the installation. At least one influencing signal (HTH, HCC, HCR) is generated in dependence on a comparison between the calculated value and at least one comparison value for the parameter, and the influencing signal is supplied to the control equipment to influence this in a direction which limits the value of the stress parameter.The member (HAS) comprises a monitoring device (PD, UA, TR, TT) for calculating the value of the stress parameter.