A preliminary look at the feasibility of VSC HVdc in Manitoba

Due to the fast-growing presence of VSC technology on the market and advancements including reduced losses, ability to operate at higher currents and using overhead lines, preliminary studies were undertaken to evaluate the feasibility of using VSC technology for the third HVdc Bipole III planned for Manitoba. Manitoba currently has two conventional LCC HVdc Bipoles I and II. Studies showed a VSC link to be technically feasible for Bipole III and would likely eliminate the need for 1000 MVA of new synchronous condensers. In comparison to a conventional LCC link, a VSC link showed improvement in system performance, particularly for frequency dips, during remote faults in the southern system (at the inverter end). Worse performance was noted for VSC DC overhead line faults, but results were still within the system acceptance criteria. A brief look at replacing Bipoles I and II with VSC technology also showed promising results, with the likelihood of being able to retire some of the existing synchronous condensers currently needed at the inverters. The nature of the results warrants future study and consideration of VSC technology for HVdc transmission in Manitoba.