Project: Interaction Study in Manitoba

Service: SSR

Client: Manitoba Hydro

Country: Canada

Year: 2012


TGS carried out a detailed sub-synchronous interaction study for the Manitoba Hydro system using our small signal stability assessment tool (TGSSR). Manitoba Hydro is currently adding a third HVDC bipole near to their existing two Nelson River Bipoles 1 and 2. The purpose of this study was to identify any potential controller interactions or SSR issues in the system. TGS Study services:

  • Interaction Study — performed using TGSSR (in-house small signal stability program)
    • Identification of DC resonances in the three HVDC bipoles 1, 2 and 3
    • Possible controller interaction between the three HVDC bipoles (for both LCC and VSC option for bipole 3)
    • Impact of series-compensated lines close to the three HVDC bipoles


The study was performed for a relatively large system with 400 buses, three LCC HVDC bipoles, One VSC bipole and around 100 generators (about 5000 states). It was possible to identify an existing control oscillation problem of one of the HVDC bipoles and hence to verify the accuracy of the study.