| Abstract [eng] |
After completing analysis on available literature sources it was found that for electrical energy transmission in long distances cables with polymeric extruded insulation and VSC type converters are becoming more and more popular. Also there was noticed that VSC type converters have better working principles regarding polymeric cables, but space charge trapping on insulation layer still deeply impacts values of electric field in insulation layer on steady or changing working regimes. In order to analyze main aspects of high voltage direct current cables working modes there was created a high voltage direct cable and converter station system model in MATLAB environment using parameters from NordBalt link. 12 main working modes form literature sources were simulated. Working modes consisted of: cable energization with energy transmission, polarity reversal with energy transmission, cable energization without energy transmission, energy transmission turn-on after cable energization, cable energization with energy transmission with 100% greater current, cable energization with energy transmission with 50% higher voltage, fast cable energization with energy transmission, cable energization with energy transmission when cooling properties of cable are worsen, positive polarity overvoltage peak on cable energization with energy transmission working mode, negative polarity overvoltage peak on cable energization with energy transmission working mode, negative pole energization with energy transmission, warm cable energization with energy transmission. After completing simulations results showed the main aspects (characteristics of insulation) influencing cable insulation aging. During analysis there were found margins of these parameters oscillation and topics for further analysis were named. |
