With the development of large-scale new energy

many regional energy bases appear

the traditional AC connected grid has small capacity

high loss

and great influence in the regional AC systems

VSC-HVDC is economic and stable

and can save the power transmission channel

large regional energy base paralleled in grids with multi-infeed VSC

then transmits electricity by LCC channel

and can solve the above problems. Firstly

we discussed the feasibility of multi-infeed DC grid-connection

compared the AC/DC transmission technology

and evaluated the engineering application of the price. Then

we designed the topology of multi-infeed VSC grid and traditional AC grid

and calculated the system parameters of two systems. Finally

we used the DIg SILENT software to model and simulate

analyzed static characteristic of two grid-connected systems under normal working condition

and compared their transient characteristics by the fault disturbance of wind farm. Simulation results can determine the superiority of multi-infeed DC integration of new energy

and the topology can restrain the fluctuation of new energy

increased consumption of new energy

and reduce dependence of AC power network for traditional LCC-HVDC.