Aiming at the shortcomings of the traditional HVDC
the author introduced the basic principle of the new HVDC transmission system firstly
and established its steady-state mode.Then
the author analyzed the control mode in which the novel HVDC system combine transferring power and compensating harmonic through instantaneous reactive power theory when it connects to the low voltage grid containing phase commute rectifier device that bring a great deal harmonic.Finally
this method’s feasibility is validated by the examination.