Low-frequency alternating current (LFAC) is an attractive approach for integrating offshore wind energy. Since actively commutated current source converters (CSCs) do not require a large number of capacitors and have the capability of black start

this paper then proposes an LFAC system for offshore wind farm connection based on fundamental-frequency-modulated CSCs used as onshore back-to-back converter stations. To reveal the operation principle

the CSC mathematical model is first performed

and system parameters are designed. Moreover

a coordinated control strategy of the wind turbine and the low-frequency-side CSC is proposed to stabilize AC voltage amplitude while regulating frequency. Furthermore

a black-start control method is introduced for the LFAC system's start-up. Then

typical operating conditions such as black start

wind speed fluctuations

and typical grid failures are simulated and analyzed in PSCAD. Eventually

the analysis of comparison among different solutions is carried out to verify the economics and feasibility of the proposal.