Limitations to loading the Manitoba Hydro future three-bipole, multi-egress, multi-infeed HVdc system and mitigation strategies

The Manitoba Hydro major transmission system features a topology consisting of very high HVdc penetration level, tightly coupled rectifiers as well as tightly coupled inverters. The tight coupling at the rectifiers or the sending end results in multi-egress system characteristics, where as the tight coupling at the inverters or the receiving end results in its multi-infeed characteristics. This paper discusses the limitations to loading the planned Manitoba Hydro three-Bipole HVdc system that can be characterised as a multi-egress and multi-infeed system. The mitigation strategies to overcome the challenges encountered in the planning process are discussed as well.