Study on the SSO damping characteristic and damping control of Mongolia-China HVDC transmission system

The interaction exists between the China-Mongolia High Voltage Direct Current (HVDC) converters and turbine-generators at the coal-electricity base, and negative electrical damping provided by HVDC may cause subsynchronous oscillation(SSO). This paper studies on the SSO damping controller (SSDC) principle, SSDC input signal select, SSDC broadband design and narrowband design approach, etc. The SSO characteristics and damping control ability of the various turbine-generators and power output, etc. are researched.